Introduce an upgrade/downgrade unit tester utility

.bazelrc

@@ -1,9 +1,3 @@
-common --enable_platform_specific_config
-
-build --repo_env=CC=clang --repo_env=CXX=clang++
-
-build:linux --cxxopt=-std=c++20
-build:macos --cxxopt=-std=c++20 --cpu=darwin_x86_64
-build:windows --cxxopt=/std:c++20 --cxxopt=/Zc:preprocessor
+build --repo_env=CC=clang --repo_env=CXX=clang++ --cxxopt="-std=c++17"
 
 try-import %workspace%/local.bazelrc

.devcontainer/devcontainer.json

@@ -1,6 +1,6 @@
 {
   "extensions": [
-    "rust-lang.rust-analyzer",
+    "rust-lang.rust",
     "bungcip.better-toml",
     "github.vscode-codeql",
     "hbenl.vscode-test-explorer",

.github/labeler.yml

@@ -11,7 +11,7 @@ Go:
   - change-notes/**/*go.*
 
 Java:
-  - any: [ 'java/**/*', '!java/kotlin-extractor/**/*', '!java/ql/test/kotlin/**/*' ]
+  - any: [ 'java/**/*', '!java/kotlin-extractor/**/*', '!java/kotlin-explorer/**/*', '!java/ql/test/kotlin/**/*' ]
   - change-notes/**/*java.*
 
 JS:
@@ -20,6 +20,7 @@ JS:
 
 Kotlin:
   - java/kotlin-extractor/**/*
+  - java/kotlin-explorer/**/*
   - java/ql/test/kotlin/**/*
 
 Python:

.github/workflows/check-change-note.yml

@@ -11,6 +11,7 @@ on:
       - "*/ql/lib/**/*.yml"
       - "!**/experimental/**"
       - "!ql/**"
+      - "!swift/**"
       - ".github/workflows/check-change-note.yml"
 
 jobs:
@@ -26,9 +27,9 @@ jobs:
         run: |
           gh api 'repos/${{github.repository}}/pulls/${{github.event.number}}/files' --paginate --jq 'any(.[].filename ; test("/change-notes/.*[.]md$"))' |
           grep true -c
-      - name: Fail if the change note filename doesn't match the expected format. The file name must be of the form 'YYYY-MM-DD.md', 'YYYY-MM-DD-{title}.md', where '{title}' is arbitrary text, or released/x.y.z.md for released change-notes
+      - name: Fail if the change note filename doesn't match the expected format. The file name must be of the form 'YYYY-MM-DD.md' or 'YYYY-MM-DD-{title}.md', where '{title}' is arbitrary text.
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         run: |
-          gh api 'repos/${{github.repository}}/pulls/${{github.event.number}}/files' --paginate --jq '[.[].filename | select(test("/change-notes/.*[.]md$"))] | all(test("/change-notes/[0-9]{4}-[0-9]{2}-[0-9]{2}.*[.]md$") or test("/change-notes/released/[0-9]*[.][0-9]*[.][0-9]*[.]md$"))' |
+          gh api 'repos/${{github.repository}}/pulls/${{github.event.number}}/files' --paginate --jq '[.[].filename | select(test("/change-notes/.*[.]md$"))] | all(test("/change-notes/[0-9]{4}-[0-9]{2}-[0-9]{2}.*[.]md$"))' |
           grep true -c

.github/workflows/check-implicit-this.yml

@@ -1,29 +0,0 @@
-name: "Check implicit this warnings"
-
-on:
-  workflow_dispatch:
-  pull_request:
-    paths:
-      - "**qlpack.yml"
-    branches:
-      - main
-      - "rc/*"
-
-jobs:
-  check:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v3
-      - name: Check that implicit this warnings is enabled for all packs
-        shell: bash
-        run: |
-          EXIT_CODE=0
-          packs="$(find . -iname 'qlpack.yml')"
-          for pack_file in ${packs}; do
-            option="$(yq '.warnOnImplicitThis' ${pack_file})"
-            if [ "${option}" != "true" ]; then
-              echo "::error file=${pack_file}::warnOnImplicitThis property must be set to 'true' for pack ${pack_file}"
-              EXIT_CODE=1
-            fi
-          done
-          exit "${EXIT_CODE}"

.github/workflows/csv-coverage-pr-artifacts.yml

@@ -10,7 +10,6 @@ on:
       - "*/ql/src/**/*.qll"
       - "*/ql/lib/**/*.ql"
       - "*/ql/lib/**/*.qll"
-      - "*/ql/lib/ext/**/*.yml"
       - "misc/scripts/library-coverage/*.py"
       # input data files
       - "*/documentation/library-coverage/cwe-sink.csv"

.github/workflows/ql-for-ql-build.yml

@@ -32,7 +32,7 @@ jobs:
           path: |
             ql/extractor-pack/
             ql/target/release/buramu
-          key: ${{ runner.os }}-${{ steps.os_version.outputs.version }}-extractor-${{ hashFiles('ql/**/Cargo.lock') }}-${{ hashFiles('shared/tree-sitter-extractor') }}-${{ hashFiles('ql/**/*.rs') }}
+          key: ${{ runner.os }}-${{ steps.os_version.outputs.version }}-extractor-${{ hashFiles('ql/**/Cargo.lock') }}-${{ hashFiles('ql/**/*.rs') }}
       - name: Cache cargo
         if: steps.cache-extractor.outputs.cache-hit != 'true'
         uses: actions/cache@v3

.github/workflows/ruby-build.yml

@@ -61,7 +61,7 @@ jobs:
             ruby/extractor/target/release/codeql-extractor-ruby
             ruby/extractor/target/release/codeql-extractor-ruby.exe
             ruby/extractor/ql/lib/codeql/ruby/ast/internal/TreeSitter.qll
-          key: ${{ runner.os }}-${{ steps.os_version.outputs.version }}-ruby-extractor-${{ hashFiles('ruby/extractor/rust-toolchain.toml', 'ruby/extractor/Cargo.lock') }}-${{ hashFiles('shared/tree-sitter-extractor') }}-${{ hashFiles('ruby/extractor/**/*.rs') }}
+          key: ${{ runner.os }}-${{ steps.os_version.outputs.version }}-ruby-extractor-${{ hashFiles('ruby/extractor/rust-toolchain.toml', 'ruby/extractor/Cargo.lock') }}--${{ hashFiles('ruby/extractor/**/*.rs') }}
       - uses: actions/cache@v3
         if: steps.cache-extractor.outputs.cache-hit != 'true'
         with:

.github/workflows/swift.yml

@@ -16,7 +16,6 @@ on:
     branches:
       - main
       - rc/*
-      - codeql-cli-*
   push:
     paths:
       - "swift/**"
@@ -31,7 +30,6 @@ on:
     branches:
       - main
       - rc/*
-      - codeql-cli-*
 
 jobs:
   # not using a matrix as you cannot depend on a specific job in a matrix, and we want to start linux checks

.github/workflows/sync-files.yml

@@ -17,6 +17,4 @@ jobs:
       - uses: actions/checkout@v3
       - name: Check synchronized files
         run: python config/sync-files.py
-      - name: Check dbscheme fragments
-        run: python config/sync-dbscheme-fragments.py
 

.github/workflows/tree-sitter-extractor-test.yml

@@ -1,46 +0,0 @@
-name: Test tree-sitter-extractor
-
-on:
-  push:
-    paths:
-      - "shared/tree-sitter-extractor/**"
-      - .github/workflows/tree-sitter-extractor-test.yml
-    branches:
-      - main
-      - "rc/*"
-  pull_request:
-    paths:
-      - "shared/tree-sitter-extractor/**"
-      - .github/workflows/tree-sitter-extractor-test.yml
-    branches:
-      - main
-      - "rc/*"
-
-env:
-  CARGO_TERM_COLOR: always
-
-defaults:
-  run:
-    working-directory: shared/tree-sitter-extractor
-
-jobs:
-  test:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v3
-      - name: Check formatting
-        run: cargo fmt --all -- --check
-      - name: Run tests
-        run: cargo test --verbose
-  fmt:
-    runs-on: ubuntu-latest  
-    steps:
-      - uses: actions/checkout@v3
-      - name: Check formatting
-        run: cargo fmt --check
-  clippy:
-    runs-on: ubuntu-latest  
-    steps:
-      - uses: actions/checkout@v3
-      - name: Run clippy
-        run: cargo clippy -- --no-deps -D warnings -A clippy::new_without_default -A clippy::too_many_arguments

.gitignore

@@ -11,6 +11,12 @@
 */ql/test/**/*.actual
 */ql/test/**/go.sum
 
+# upgrade/downgrade script tests projects and artifacts
+**/upgrades/**/test/*.testproj
+**/upgrades/**/test/*.actual
+**/downgrades/**/test/*.testproj
+**/downgrades/**/test/*.actual
+
 # Visual studio temporaries, except a file used by QL4VS
 .vs/*
 !.vs/VSWorkspaceSettings.json

.pre-commit-config.yaml

@@ -5,9 +5,9 @@ repos:
     rev: v3.2.0
     hooks:
       - id: trailing-whitespace
-        exclude: /test/.*$(?<!\.ql)(?<!\.qll)(?<!\.qlref)|.*\.patch
+        exclude: /test/.*$(?<!\.ql)(?<!\.qll)(?<!\.qlref)
       - id: end-of-file-fixer
-        exclude: /test/.*$(?<!\.ql)(?<!\.qll)(?<!\.qlref)|.*\.patch
+        exclude: /test/.*$(?<!\.ql)(?<!\.qll)(?<!\.qlref)
 
   - repo: https://github.com/pre-commit/mirrors-clang-format
     rev: v13.0.1
@@ -21,11 +21,6 @@ repos:
       - id: autopep8
         files: ^misc/codegen/.*\.py
 
-  - repo: https://github.com/warchant/pre-commit-buildifier
-    rev: 0.0.2
-    hooks:
-      - id: buildifier
-
   - repo: local
     hooks:
       - id: codeql-format

.vscode/tasks.json

@@ -22,22 +22,6 @@
                 "command": "${config:python.pythonPath}",
             },
             "problemMatcher": []
-        },
-        {
-            "label": "Accept .expected changes from CI",
-            "type": "process",
-            // Non-Windows OS will usually have Python 3 already installed at /usr/bin/python3.
-            "command": "python3",
-            "args": [
-                "misc/scripts/accept-expected-changes-from-ci.py"
-            ],
-            "group": "build",
-            "windows": {
-                // On Windows, use whatever Python interpreter is configured for this workspace. The default is
-                // just `python`, so if Python is already on the path, this will find it.
-                "command": "${config:python.pythonPath}",
-            },
-            "problemMatcher": []
         }
     ]
-}
+}

CODEOWNERS

@@ -8,6 +8,7 @@
 /swift/ @github/codeql-swift
 /misc/codegen/ @github/codeql-swift
 /java/kotlin-extractor/ @github/codeql-kotlin
+/java/kotlin-explorer/ @github/codeql-kotlin
 
 # ML-powered queries
 /javascript/ql/experimental/adaptivethreatmodeling/ @github/codeql-ml-powered-queries-reviewers
@@ -39,6 +40,3 @@ WORKSPACE.bazel @github/codeql-ci-reviewers
 /.github/workflows/ql-for-ql-* @github/codeql-ql-for-ql-reviewers
 /.github/workflows/ruby-* @github/codeql-ruby
 /.github/workflows/swift.yml @github/codeql-swift
-
-# Misc
-/misc/scripts/accept-expected-changes-from-ci.py @RasmusWL

CONTRIBUTING.md

@@ -14,16 +14,14 @@ If you have an idea for a query that you would like to share with other CodeQL u
 
 1. **Directory structure**
 
-    There are eight language-specific query directories in this repository:
+    There are six language-specific query directories in this repository:
 
       * C/C++: `cpp/ql/src`
       * C#: `csharp/ql/src`
-      * Go: `go/ql/src`
-      * Java/Kotlin: `java/ql/src`
+      * Java: `java/ql/src`
       * JavaScript: `javascript/ql/src`
       * Python: `python/ql/src`
       * Ruby: `ruby/ql/src`
-      * Swift: `swift/ql/src`
 
     Each language-specific directory contains further subdirectories that group queries based on their `@tags` or purpose.
     - Experimental queries and libraries are stored in the `experimental` subdirectory within each language-specific directory in the [CodeQL repository](https://github.com/github/codeql). For example, experimental Java queries and libraries are stored in `java/ql/src/experimental` and any corresponding tests in `java/ql/test/experimental`.

config/dbscheme-fragments.json

@@ -1,33 +0,0 @@
-{
-  "files": [
-    "javascript/ql/lib/semmlecode.javascript.dbscheme",
-    "python/ql/lib/semmlecode.python.dbscheme",
-    "ruby/ql/lib/ruby.dbscheme",
-    "ql/ql/src/ql.dbscheme"
-  ],
-  "fragments": [
-    "/*- External data -*/",
-    "/*- Files and folders -*/",
-    "/*- Diagnostic messages -*/",
-    "/*- Diagnostic messages: severity -*/",
-    "/*- Source location prefix -*/",
-    "/*- Lines of code -*/",
-    "/*- Configuration files with key value pairs -*/",
-    "/*- YAML -*/",
-    "/*- XML Files -*/",
-    "/*- XML: sourceline -*/",
-    "/*- DEPRECATED: External defects and metrics -*/",
-    "/*- DEPRECATED: Snapshot date -*/",
-    "/*- DEPRECATED: Duplicate code -*/",
-    "/*- DEPRECATED: Version control data -*/",
-    "/*- JavaScript-specific part -*/",
-    "/*- Ruby dbscheme -*/",
-    "/*- Erb dbscheme -*/",
-    "/*- QL dbscheme -*/",
-    "/*- Dbscheme dbscheme -*/",
-    "/*- Yaml dbscheme -*/",
-    "/*- Blame dbscheme -*/",
-    "/*- JSON dbscheme -*/",
-    "/*- Python dbscheme -*/"
-  ]
-}

config/identical-files.json

@@ -40,6 +40,7 @@
     "csharp/ql/lib/semmle/code/csharp/dataflow/internal/DataFlowImpl3.qll",
     "csharp/ql/lib/semmle/code/csharp/dataflow/internal/DataFlowImpl4.qll",
     "csharp/ql/lib/semmle/code/csharp/dataflow/internal/DataFlowImpl5.qll",
+    "csharp/ql/lib/semmle/code/csharp/dataflow/internal/DataFlowImplForContentDataFlow.qll",
     "go/ql/lib/semmle/go/dataflow/internal/DataFlowImpl1.qll",
     "go/ql/lib/semmle/go/dataflow/internal/DataFlowImpl2.qll",
     "go/ql/lib/semmle/go/dataflow/internal/DataFlowImplForStringsNewReplacer.qll",
@@ -47,6 +48,7 @@
     "python/ql/lib/semmle/python/dataflow/new/internal/DataFlowImpl2.qll",
     "python/ql/lib/semmle/python/dataflow/new/internal/DataFlowImpl3.qll",
     "python/ql/lib/semmle/python/dataflow/new/internal/DataFlowImpl4.qll",
+    "python/ql/lib/semmle/python/dataflow/new/internal/DataFlowImplForRegExp.qll",
     "ruby/ql/lib/codeql/ruby/dataflow/internal/DataFlowImpl1.qll",
     "ruby/ql/lib/codeql/ruby/dataflow/internal/DataFlowImpl2.qll",
     "ruby/ql/lib/codeql/ruby/dataflow/internal/DataFlowImplForHttpClientLibraries.qll",
@@ -511,8 +513,7 @@
   "SensitiveDataHeuristics Python/JS": [
     "javascript/ql/lib/semmle/javascript/security/internal/SensitiveDataHeuristics.qll",
     "python/ql/lib/semmle/python/security/internal/SensitiveDataHeuristics.qll",
-    "ruby/ql/lib/codeql/ruby/security/internal/SensitiveDataHeuristics.qll",
-    "swift/ql/lib/codeql/swift/security/internal/SensitiveDataHeuristics.qll"
+    "ruby/ql/lib/codeql/ruby/security/internal/SensitiveDataHeuristics.qll"
   ],
   "CFG": [
     "csharp/ql/lib/semmle/code/csharp/controlflow/internal/ControlFlowGraphImplShared.qll",
@@ -523,10 +524,6 @@
     "python/ql/lib/semmle/python/dataflow/new/internal/TypeTracker.qll",
     "ruby/ql/lib/codeql/ruby/typetracking/TypeTracker.qll"
   ],
-  "SummaryTypeTracker": [
-    "python/ql/lib/semmle/python/dataflow/new/internal/SummaryTypeTracker.qll",
-    "ruby/ql/lib/codeql/ruby/typetracking/internal/SummaryTypeTracker.qll"
-  ],
   "AccessPathSyntax": [
     "csharp/ql/lib/semmle/code/csharp/dataflow/internal/AccessPathSyntax.qll",
     "go/ql/lib/semmle/go/dataflow/internal/AccessPathSyntax.qll",
@@ -603,4 +600,4 @@
     "python/ql/lib/semmle/python/security/internal/EncryptionKeySizes.qll",
     "java/ql/lib/semmle/code/java/security/internal/EncryptionKeySizes.qll"
   ]
-}
+}

config/sync-dbscheme-fragments.py

@@ -1,86 +0,0 @@
-#!/usr/bin/env python3
-
-import argparse
-import json
-import os
-import pathlib
-import re
-
-
-def make_groups(blocks):
-    groups = {}
-    for block in blocks:
-        groups.setdefault("".join(block["lines"]), []).append(block)
-    return list(groups.values())
-
-
-def validate_fragments(fragments):
-    ok = True
-    for header, blocks in fragments.items():
-        groups = make_groups(blocks)
-        if len(groups) > 1:
-            ok = False
-            print("Warning: dbscheme fragments with header '{}' are different for {}".format(header, ["{}:{}:{}".format(
-                group[0]["file"], group[0]["start"], group[0]["end"]) for group in groups]))
-    return ok
-
-
-def main():
-    script_path = os.path.realpath(__file__)
-    script_dir = os.path.dirname(script_path)
-    parser = argparse.ArgumentParser(
-        prog=os.path.basename(script_path),
-        description='Sync dbscheme fragments across files.'
-    )
-    parser.add_argument('files', metavar='dbscheme_file', type=pathlib.Path, nargs='*', default=[],
-                        help='dbscheme files to check')
-    args = parser.parse_args()
-
-    with open(os.path.join(script_dir, "dbscheme-fragments.json"), "r") as f:
-        config = json.load(f)
-
-    fragment_headers = set(config["fragments"])
-    fragments = {}
-    ok = True
-    for file in args.files + config["files"]:
-        with open(os.path.join(os.path.dirname(script_dir), file), "r") as dbscheme:
-            header = None
-            line_number = 1
-            block = {"file": file, "start": line_number,
-                     "end": None, "lines": []}
-
-            def end_block():
-                block["end"] = line_number - 1
-                if len(block["lines"]) > 0:
-                    if header is None:
-                        if re.match(r'(?m)\A(\s|//.*$|/\*(\**[^\*])*\*+/)*\Z', "".join(block["lines"])):
-                            # Ignore comments at the beginning of the file
-                            pass
-                        else:
-                            ok = False
-                            print("Warning: dbscheme fragment without header: {}:{}:{}".format(
-                                block["file"], block["start"], block["end"]))
-                    else:
-                        fragments.setdefault(header, []).append(block)
-            for line in dbscheme:
-                m = re.match(r"^\/\*-.*-\*\/$", line)
-                if m:
-                    end_block()
-                    header = line.strip()
-                    if header not in fragment_headers:
-                        ok = False
-                        print("Warning: unknown header for dbscheme fragment: '{}': {}:{}".format(
-                            header, file, line_number))
-                    block = {"file": file, "start": line_number,
-                             "end": None, "lines": []}
-                block["lines"].append(line)
-                line_number += 1
-            block["lines"].append('\n')
-            line_number += 1
-            end_block()
-    if not ok or not validate_fragments(fragments):
-        exit(1)
-
-
-if __name__ == "__main__":
-    main()

cpp/downgrades/qlpack.yml

@@ -2,4 +2,3 @@ name: codeql/cpp-downgrades
 groups: cpp
 downgrades: .
 library: true
-warnOnImplicitThis: true

cpp/ql/examples/qlpack.yml

@@ -4,4 +4,3 @@ groups:
   - examples
 dependencies:
   codeql/cpp-all: ${workspace}
-warnOnImplicitThis: true

cpp/ql/lib/CHANGELOG.md

@@ -1,65 +1,3 @@
-## 0.8.1
-
-### Deprecated APIs
-
-* The library `semmle.code.cpp.dataflow.DataFlow` has been deprecated. Please use `semmle.code.cpp.dataflow.new.DataFlow` instead.
-
-### New Features
-
-* The `DataFlow::StateConfigSig` signature module has gained default implementations for `isBarrier/2` and `isAdditionalFlowStep/4`. 
-  Hence it is no longer needed to provide `none()` implementations of these predicates if they are not needed.
-
-### Minor Analysis Improvements
-
-* Data flow configurations can now include a predicate `neverSkip(Node node)`
-  in order to ensure inclusion of certain nodes in the path explanations. The
-  predicate defaults to the end-points of the additional flow steps provided in
-  the configuration, which means that such steps now always are visible by
-  default in path explanations.
-* The `IRGuards` library has improved handling of pointer addition and subtraction operations.
-
-## 0.8.0
-
-### New Features
-
-* The `ProductFlow::StateConfigSig` signature now includes default predicates for `isBarrier1`, `isBarrier2`, `isAdditionalFlowStep1`, and `isAdditionalFlowStep1`. Hence, it is no longer needed to provide `none()` implementations of these predicates if they are not needed.
-
-### Minor Analysis Improvements
-
-* Deleted the deprecated `getURL` predicate from the `Container`, `Folder`, and `File` classes. Use the `getLocation` predicate instead.
-
-## 0.7.4
-
-No user-facing changes.
-
-## 0.7.3
-
-### Minor Analysis Improvements
-
-* Deleted the deprecated `hasCopyConstructor` predicate from the `Class` class in `Class.qll`.
-* Deleted many deprecated predicates and classes with uppercase `AST`, `SSA`, `CFG`, `API`, etc. in their names. Use the PascalCased versions instead.
-* Deleted the deprecated `CodeDuplication.qll` file.
-
-## 0.7.2
-
-### New Features
-
-* Added an AST-based interface (`semmle.code.cpp.rangeanalysis.new.RangeAnalysis`) for the relative range analysis library.
-* A new predicate `BarrierGuard::getAnIndirectBarrierNode` has been added to the new dataflow library (`semmle.code.cpp.dataflow.new.DataFlow`) to mark indirect expressions as barrier nodes using the `BarrierGuard` API.
-
-### Major Analysis Improvements
-
-* In the intermediate representation, handling of control flow after non-returning calls has been improved. This should remove false positives in queries that use the intermedite representation or libraries based on it, including the new data flow library.
-
-### Minor Analysis Improvements
-
-* The `StdNamespace` class now also includes all inline namespaces that are children of `std` namespace.
-* The new dataflow (`semmle.code.cpp.dataflow.new.DataFlow`) and taint-tracking libraries (`semmle.code.cpp.dataflow.new.TaintTracking`) now support tracking flow through static local variables.
-
-## 0.7.1
-
-No user-facing changes.
-
 ## 0.7.0
 
 ### Breaking Changes

cpp/ql/lib/change-notes/released/0.7.1.md

@@ -1,3 +0,0 @@
-## 0.7.1
-
-No user-facing changes.

cpp/ql/lib/change-notes/released/0.7.2.md

@@ -1,15 +0,0 @@
-## 0.7.2
-
-### New Features
-
-* Added an AST-based interface (`semmle.code.cpp.rangeanalysis.new.RangeAnalysis`) for the relative range analysis library.
-* A new predicate `BarrierGuard::getAnIndirectBarrierNode` has been added to the new dataflow library (`semmle.code.cpp.dataflow.new.DataFlow`) to mark indirect expressions as barrier nodes using the `BarrierGuard` API.
-
-### Major Analysis Improvements
-
-* In the intermediate representation, handling of control flow after non-returning calls has been improved. This should remove false positives in queries that use the intermedite representation or libraries based on it, including the new data flow library.
-
-### Minor Analysis Improvements
-
-* The `StdNamespace` class now also includes all inline namespaces that are children of `std` namespace.
-* The new dataflow (`semmle.code.cpp.dataflow.new.DataFlow`) and taint-tracking libraries (`semmle.code.cpp.dataflow.new.TaintTracking`) now support tracking flow through static local variables.

cpp/ql/lib/change-notes/released/0.7.3.md

@@ -1,7 +0,0 @@
-## 0.7.3
-
-### Minor Analysis Improvements
-
-* Deleted the deprecated `hasCopyConstructor` predicate from the `Class` class in `Class.qll`.
-* Deleted many deprecated predicates and classes with uppercase `AST`, `SSA`, `CFG`, `API`, etc. in their names. Use the PascalCased versions instead.
-* Deleted the deprecated `CodeDuplication.qll` file.

cpp/ql/lib/change-notes/released/0.7.4.md

@@ -1,3 +0,0 @@
-## 0.7.4
-
-No user-facing changes.

cpp/ql/lib/change-notes/released/0.8.0.md

@@ -1,9 +0,0 @@
-## 0.8.0
-
-### New Features
-
-* The `ProductFlow::StateConfigSig` signature now includes default predicates for `isBarrier1`, `isBarrier2`, `isAdditionalFlowStep1`, and `isAdditionalFlowStep1`. Hence, it is no longer needed to provide `none()` implementations of these predicates if they are not needed.
-
-### Minor Analysis Improvements
-
-* Deleted the deprecated `getURL` predicate from the `Container`, `Folder`, and `File` classes. Use the `getLocation` predicate instead.

cpp/ql/lib/change-notes/released/0.8.1.md

@@ -1,19 +0,0 @@
-## 0.8.1
-
-### Deprecated APIs
-
-* The library `semmle.code.cpp.dataflow.DataFlow` has been deprecated. Please use `semmle.code.cpp.dataflow.new.DataFlow` instead.
-
-### New Features
-
-* The `DataFlow::StateConfigSig` signature module has gained default implementations for `isBarrier/2` and `isAdditionalFlowStep/4`. 
-  Hence it is no longer needed to provide `none()` implementations of these predicates if they are not needed.
-
-### Minor Analysis Improvements
-
-* Data flow configurations can now include a predicate `neverSkip(Node node)`
-  in order to ensure inclusion of certain nodes in the path explanations. The
-  predicate defaults to the end-points of the additional flow steps provided in
-  the configuration, which means that such steps now always are visible by
-  default in path explanations.
-* The `IRGuards` library has improved handling of pointer addition and subtraction operations.

cpp/ql/lib/codeql-pack.release.yml

@@ -1,2 +1,2 @@
 ---
-lastReleaseVersion: 0.8.1
+lastReleaseVersion: 0.7.0

cpp/ql/lib/experimental/semmle/code/cpp/dataflow/ProductFlow.qll

@@ -1,29 +1,7 @@
-/**
- * Provides a library for global (inter-procedural) data flow analysis of two
- * values "simultaneously". This can be used, for example, if you want to track
- * a memory allocation as well as the size of the allocation.
- *
- * Intuitively, you can think of this as regular dataflow, but where each node
- * in the dataflow graph has been replaced by a pair of nodes `(node1, node2)`,
- * and two node pairs `(n11, n12)`, `(n21, n22)` is then connected by a dataflow
- * edge if there's a regular dataflow edge between `n11` and `n21`, and `n12`
- * and `n22`.
- *
- * Note that the above intuition does not reflect the actual implementation.
- */
-
-import semmle.code.cpp.dataflow.new.DataFlow
-private import DataFlowPrivate
-private import DataFlowUtil
-private import DataFlowImplCommon
+import semmle.code.cpp.ir.dataflow.DataFlow
 private import codeql.util.Unit
 
-/**
- * Provides classes for performing global (inter-procedural) data flow analyses
- * on a product dataflow graph.
- */
 module ProductFlow {
-  /** An input configuration for product data-flow. */
   signature module ConfigSig {
     /**
      * Holds if `(source1, source2)` is a relevant data flow source.
@@ -89,9 +67,6 @@ module ProductFlow {
     default predicate isBarrierIn2(DataFlow::Node node) { none() }
   }
 
-  /**
-   * The output of a global data flow computation.
-   */
   module Global<ConfigSig Config> {
     private module StateConfig implements StateConfigSig {
       class FlowState1 = Unit;
@@ -160,7 +135,6 @@ module ProductFlow {
     import GlobalWithState<StateConfig>
   }
 
-  /** An input configuration for data flow using flow state. */
   signature module StateConfigSig {
     bindingset[this]
     class FlowState1;
@@ -192,13 +166,13 @@ module ProductFlow {
      * Holds if data flow through `node` is prohibited through the first projection of the product
      * dataflow graph when the flow state is `state`.
      */
-    default predicate isBarrier1(DataFlow::Node node, FlowState1 state) { none() }
+    predicate isBarrier1(DataFlow::Node node, FlowState1 state);
 
     /**
      * Holds if data flow through `node` is prohibited through the second projection of the product
      * dataflow graph when the flow state is `state`.
      */
-    default predicate isBarrier2(DataFlow::Node node, FlowState2 state) { none() }
+    predicate isBarrier2(DataFlow::Node node, FlowState2 state);
 
     /**
      * Holds if data flow through `node` is prohibited through the first projection of the product
@@ -237,11 +211,9 @@ module ProductFlow {
      *
      * This step is only applicable in `state1` and updates the flow state to `state2`.
      */
-    default predicate isAdditionalFlowStep1(
+    predicate isAdditionalFlowStep1(
       DataFlow::Node node1, FlowState1 state1, DataFlow::Node node2, FlowState1 state2
-    ) {
-      none()
-    }
+    );
 
     /**
      * Holds if data may flow from `node1` to `node2` in addition to the normal data-flow steps in
@@ -255,11 +227,9 @@ module ProductFlow {
      *
      * This step is only applicable in `state1` and updates the flow state to `state2`.
      */
-    default predicate isAdditionalFlowStep2(
+    predicate isAdditionalFlowStep2(
       DataFlow::Node node1, FlowState2 state1, DataFlow::Node node2, FlowState2 state2
-    ) {
-      none()
-    }
+    );
 
     /**
      * Holds if data flow into `node` is prohibited in the first projection of the product
@@ -274,9 +244,6 @@ module ProductFlow {
     default predicate isBarrierIn2(DataFlow::Node node) { none() }
   }
 
-  /**
-   * The output of a global data flow computation.
-   */
   module GlobalWithState<StateConfigSig Config> {
     class PathNode1 = Flow1::PathNode;
 
@@ -290,29 +257,12 @@ module ProductFlow {
 
     class FlowState2 = Config::FlowState2;
 
-    /** Holds if data can flow from `(source1, source2)` to `(sink1, sink2)`. */
     predicate flowPath(
       Flow1::PathNode source1, Flow2::PathNode source2, Flow1::PathNode sink1, Flow2::PathNode sink2
     ) {
       reachable(source1, source2, sink1, sink2)
     }
 
-    /** Holds if data can flow from `(source1, source2)` to `(sink1, sink2)`. */
-    predicate flow(
-      DataFlow::Node source1, DataFlow::Node source2, DataFlow::Node sink1, DataFlow::Node sink2
-    ) {
-      exists(
-        Flow1::PathNode pSource1, Flow2::PathNode pSource2, Flow1::PathNode pSink1,
-        Flow2::PathNode pSink2
-      |
-        pSource1.getNode() = source1 and
-        pSource2.getNode() = source2 and
-        pSink1.getNode() = sink1 and
-        pSink2.getNode() = sink2 and
-        flowPath(pSource1, pSource2, pSink1, pSink2)
-      )
-    }
-
     private module Config1 implements DataFlow::StateConfigSig {
       class FlowState = FlowState1;
 
@@ -337,9 +287,9 @@ module ProductFlow {
       predicate isBarrierIn(DataFlow::Node node) { Config::isBarrierIn1(node) }
     }
 
-    private module Flow1 = DataFlow::GlobalWithState<Config1>;
+    module Flow1 = DataFlow::GlobalWithState<Config1>;
 
-    private module Config2 implements DataFlow::StateConfigSig {
+    module Config2 implements DataFlow::StateConfigSig {
       class FlowState = FlowState2;
 
       predicate isSource(DataFlow::Node source, FlowState state) {
@@ -369,87 +319,27 @@ module ProductFlow {
       predicate isBarrierIn(DataFlow::Node node) { Config::isBarrierIn2(node) }
     }
 
-    private module Flow2 = DataFlow::GlobalWithState<Config2>;
-
-    private predicate isSourcePair(Flow1::PathNode node1, Flow2::PathNode node2) {
-      Config::isSourcePair(node1.getNode(), node1.getState(), node2.getNode(), node2.getState())
-    }
-
-    private predicate isSinkPair(Flow1::PathNode node1, Flow2::PathNode node2) {
-      Config::isSinkPair(node1.getNode(), node1.getState(), node2.getNode(), node2.getState())
-    }
+    module Flow2 = DataFlow::GlobalWithState<Config2>;
 
     pragma[nomagic]
-    private predicate fwdReachableInterprocEntry(Flow1::PathNode node1, Flow2::PathNode node2) {
-      isSourcePair(node1, node2)
+    private predicate reachableInterprocEntry(
+      Flow1::PathNode source1, Flow2::PathNode source2, Flow1::PathNode node1, Flow2::PathNode node2
+    ) {
+      Config::isSourcePair(node1.getNode(), node1.getState(), node2.getNode(), node2.getState()) and
+      node1 = source1 and
+      node2 = source2
       or
-      fwdIsSuccessor(_, _, node1, node2)
-    }
-
-    pragma[nomagic]
-    private predicate fwdIsSuccessorExit(
-      Flow1::PathNode mid1, Flow2::PathNode mid2, Flow1::PathNode succ1, Flow2::PathNode succ2
-    ) {
-      isSinkPair(mid1, mid2) and
-      succ1 = mid1 and
-      succ2 = mid2
-      or
-      interprocEdgePair(mid1, mid2, succ1, succ2)
-    }
-
-    private predicate fwdIsSuccessor1(
-      Flow1::PathNode pred1, Flow2::PathNode pred2, Flow1::PathNode mid1, Flow2::PathNode mid2,
-      Flow1::PathNode succ1, Flow2::PathNode succ2
-    ) {
-      fwdReachableInterprocEntry(pred1, pred2) and
-      localPathStep1*(pred1, mid1) and
-      fwdIsSuccessorExit(pragma[only_bind_into](mid1), pragma[only_bind_into](mid2), succ1, succ2)
-    }
-
-    private predicate fwdIsSuccessor2(
-      Flow1::PathNode pred1, Flow2::PathNode pred2, Flow1::PathNode mid1, Flow2::PathNode mid2,
-      Flow1::PathNode succ1, Flow2::PathNode succ2
-    ) {
-      fwdReachableInterprocEntry(pred1, pred2) and
-      localPathStep2*(pred2, mid2) and
-      fwdIsSuccessorExit(pragma[only_bind_into](mid1), pragma[only_bind_into](mid2), succ1, succ2)
-    }
-
-    private predicate fwdIsSuccessor(
-      Flow1::PathNode pred1, Flow2::PathNode pred2, Flow1::PathNode succ1, Flow2::PathNode succ2
-    ) {
-      exists(Flow1::PathNode mid1, Flow2::PathNode mid2 |
-        fwdIsSuccessor1(pred1, pred2, mid1, mid2, succ1, succ2) and
-        fwdIsSuccessor2(pred1, pred2, mid1, mid2, succ1, succ2)
+      exists(
+        Flow1::PathNode midEntry1, Flow2::PathNode midEntry2, Flow1::PathNode midExit1,
+        Flow2::PathNode midExit2
+      |
+        reachableInterprocEntry(source1, source2, midEntry1, midEntry2) and
+        interprocEdgePair(midExit1, midExit2, node1, node2) and
+        localPathStep1*(midEntry1, midExit1) and
+        localPathStep2*(midEntry2, midExit2)
       )
     }
 
-    pragma[nomagic]
-    private predicate revReachableInterprocEntry(Flow1::PathNode node1, Flow2::PathNode node2) {
-      fwdReachableInterprocEntry(node1, node2) and
-      isSinkPair(node1, node2)
-      or
-      exists(Flow1::PathNode succ1, Flow2::PathNode succ2 |
-        revReachableInterprocEntry(succ1, succ2) and
-        fwdIsSuccessor(node1, node2, succ1, succ2)
-      )
-    }
-
-    private newtype TNodePair =
-      TMkNodePair(Flow1::PathNode node1, Flow2::PathNode node2) {
-        revReachableInterprocEntry(node1, node2)
-      }
-
-    private predicate pathSucc(TNodePair n1, TNodePair n2) {
-      exists(Flow1::PathNode n11, Flow2::PathNode n12, Flow1::PathNode n21, Flow2::PathNode n22 |
-        n1 = TMkNodePair(n11, n12) and
-        n2 = TMkNodePair(n21, n22) and
-        fwdIsSuccessor(n11, n12, n21, n22)
-      )
-    }
-
-    private predicate pathSuccPlus(TNodePair n1, TNodePair n2) = fastTC(pathSucc/2)(n1, n2)
-
     private predicate localPathStep1(Flow1::PathNode pred, Flow1::PathNode succ) {
       Flow1::PathGraph::edges(pred, succ) and
       pragma[only_bind_out](pred.getNode().getEnclosingCallable()) =
@@ -462,133 +352,43 @@ module ProductFlow {
         pragma[only_bind_out](succ.getNode().getEnclosingCallable())
     }
 
-    private newtype TKind =
-      TInto(DataFlowCall call) {
-        intoImpl1(_, _, call) or
-        intoImpl2(_, _, call)
-      } or
-      TOutOf(DataFlowCall call) {
-        outImpl1(_, _, call) or
-        outImpl2(_, _, call)
-      } or
-      TJump()
-
-    private predicate intoImpl1(Flow1::PathNode pred1, Flow1::PathNode succ1, DataFlowCall call) {
-      Flow1::PathGraph::edges(pred1, succ1) and
-      pred1.getNode().(ArgumentNode).getCall() = call and
-      succ1.getNode() instanceof ParameterNode
-    }
-
-    private predicate into1(Flow1::PathNode pred1, Flow1::PathNode succ1, TKind kind) {
-      exists(DataFlowCall call |
-        kind = TInto(call) and
-        intoImpl1(pred1, succ1, call)
-      )
-    }
-
-    private predicate outImpl1(Flow1::PathNode pred1, Flow1::PathNode succ1, DataFlowCall call) {
-      Flow1::PathGraph::edges(pred1, succ1) and
-      exists(ReturnKindExt returnKind |
-        succ1.getNode() = returnKind.getAnOutNode(call) and
-        pred1.getNode().(ReturnNodeExt).getKind() = returnKind
-      )
-    }
-
-    private predicate out1(Flow1::PathNode pred1, Flow1::PathNode succ1, TKind kind) {
-      exists(DataFlowCall call |
-        outImpl1(pred1, succ1, call) and
-        kind = TOutOf(call)
-      )
-    }
-
-    private predicate intoImpl2(Flow2::PathNode pred2, Flow2::PathNode succ2, DataFlowCall call) {
-      Flow2::PathGraph::edges(pred2, succ2) and
-      pred2.getNode().(ArgumentNode).getCall() = call and
-      succ2.getNode() instanceof ParameterNode
-    }
-
-    private predicate into2(Flow2::PathNode pred2, Flow2::PathNode succ2, TKind kind) {
-      exists(DataFlowCall call |
-        kind = TInto(call) and
-        intoImpl2(pred2, succ2, call)
-      )
-    }
-
-    private predicate outImpl2(Flow2::PathNode pred2, Flow2::PathNode succ2, DataFlowCall call) {
-      Flow2::PathGraph::edges(pred2, succ2) and
-      exists(ReturnKindExt returnKind |
-        succ2.getNode() = returnKind.getAnOutNode(call) and
-        pred2.getNode().(ReturnNodeExt).getKind() = returnKind
-      )
-    }
-
-    private predicate out2(Flow2::PathNode pred2, Flow2::PathNode succ2, TKind kind) {
-      exists(DataFlowCall call |
-        kind = TOutOf(call) and
-        outImpl2(pred2, succ2, call)
-      )
-    }
-
     pragma[nomagic]
     private predicate interprocEdge1(
-      Declaration predDecl, Declaration succDecl, Flow1::PathNode pred1, Flow1::PathNode succ1,
-      TKind kind
+      Declaration predDecl, Declaration succDecl, Flow1::PathNode pred1, Flow1::PathNode succ1
     ) {
       Flow1::PathGraph::edges(pred1, succ1) and
       predDecl != succDecl and
       pred1.getNode().getEnclosingCallable() = predDecl and
-      succ1.getNode().getEnclosingCallable() = succDecl and
-      (
-        into1(pred1, succ1, kind)
-        or
-        out1(pred1, succ1, kind)
-        or
-        kind = TJump() and
-        not into1(pred1, succ1, _) and
-        not out1(pred1, succ1, _)
-      )
+      succ1.getNode().getEnclosingCallable() = succDecl
     }
 
     pragma[nomagic]
     private predicate interprocEdge2(
-      Declaration predDecl, Declaration succDecl, Flow2::PathNode pred2, Flow2::PathNode succ2,
-      TKind kind
+      Declaration predDecl, Declaration succDecl, Flow2::PathNode pred2, Flow2::PathNode succ2
     ) {
       Flow2::PathGraph::edges(pred2, succ2) and
       predDecl != succDecl and
       pred2.getNode().getEnclosingCallable() = predDecl and
-      succ2.getNode().getEnclosingCallable() = succDecl and
-      (
-        into2(pred2, succ2, kind)
-        or
-        out2(pred2, succ2, kind)
-        or
-        kind = TJump() and
-        not into2(pred2, succ2, _) and
-        not out2(pred2, succ2, _)
-      )
+      succ2.getNode().getEnclosingCallable() = succDecl
     }
 
     private predicate interprocEdgePair(
       Flow1::PathNode pred1, Flow2::PathNode pred2, Flow1::PathNode succ1, Flow2::PathNode succ2
     ) {
-      exists(Declaration predDecl, Declaration succDecl, TKind kind |
-        interprocEdge1(predDecl, succDecl, pred1, succ1, kind) and
-        interprocEdge2(predDecl, succDecl, pred2, succ2, kind)
+      exists(Declaration predDecl, Declaration succDecl |
+        interprocEdge1(predDecl, succDecl, pred1, succ1) and
+        interprocEdge2(predDecl, succDecl, pred2, succ2)
       )
     }
 
     private predicate reachable(
       Flow1::PathNode source1, Flow2::PathNode source2, Flow1::PathNode sink1, Flow2::PathNode sink2
     ) {
-      isSourcePair(source1, source2) and
-      isSinkPair(sink1, sink2) and
-      exists(TNodePair n1, TNodePair n2 |
-        n1 = TMkNodePair(source1, source2) and
-        n2 = TMkNodePair(sink1, sink2)
-      |
-        pathSuccPlus(n1, n2) or
-        n1 = n2
+      exists(Flow1::PathNode mid1, Flow2::PathNode mid2 |
+        reachableInterprocEntry(source1, source2, mid1, mid2) and
+        Config::isSinkPair(sink1.getNode(), sink1.getState(), sink2.getNode(), sink2.getState()) and
+        localPathStep1*(mid1, sink1) and
+        localPathStep2*(mid2, sink2)
       )
     }
   }

cpp/ql/lib/experimental/semmle/code/cpp/rangeanalysis/RangeAnalysis.qll

@@ -238,7 +238,7 @@ class NoReason extends Reason, TNoReason {
 class CondReason extends Reason, TCondReason {
   IRGuardCondition getCond() { this = TCondReason(result) }
 
-  override string toString() { result = this.getCond().toString() }
+  override string toString() { result = getCond().toString() }
 }
 
 /**
@@ -260,14 +260,14 @@ private predicate typeBound(IRIntegerType typ, int lowerbound, int upperbound) {
 private class NarrowingCastInstruction extends ConvertInstruction {
   NarrowingCastInstruction() {
     not this instanceof SafeCastInstruction and
-    typeBound(this.getResultIRType(), _, _)
+    typeBound(getResultIRType(), _, _)
   }
 
   /** Gets the lower bound of the resulting type. */
-  int getLowerBound() { typeBound(this.getResultIRType(), result, _) }
+  int getLowerBound() { typeBound(getResultIRType(), result, _) }
 
   /** Gets the upper bound of the resulting type. */
-  int getUpperBound() { typeBound(this.getResultIRType(), _, result) }
+  int getUpperBound() { typeBound(getResultIRType(), _, result) }
 }
 
 /**

cpp/ql/lib/experimental/semmle/code/cpp/rangeanalysis/RangeUtils.qll

@@ -109,8 +109,8 @@ private predicate safeCast(IRIntegerType fromtyp, IRIntegerType totyp) {
  */
 class PtrToPtrCastInstruction extends ConvertInstruction {
   PtrToPtrCastInstruction() {
-    this.getResultIRType() instanceof IRAddressType and
-    this.getUnary().getResultIRType() instanceof IRAddressType
+    getResultIRType() instanceof IRAddressType and
+    getUnary().getResultIRType() instanceof IRAddressType
   }
 }
 
@@ -119,7 +119,7 @@ class PtrToPtrCastInstruction extends ConvertInstruction {
  * that cannot overflow or underflow.
  */
 class SafeIntCastInstruction extends ConvertInstruction {
-  SafeIntCastInstruction() { safeCast(this.getUnary().getResultIRType(), this.getResultIRType()) }
+  SafeIntCastInstruction() { safeCast(getUnary().getResultIRType(), getResultIRType()) }
 }
 
 /**

cpp/ql/lib/experimental/semmle/code/cpp/rangeanalysis/extensions/ConstantBitwiseAndExprRange.qll

@@ -50,8 +50,8 @@ private class ConstantBitwiseAndExprRange extends SimpleRangeAnalysisExpr {
     // If an operand can have negative values, the lower bound is unconstrained.
     // Otherwise, the lower bound is zero.
     exists(float lLower, float rLower |
-      lLower = getFullyConvertedLowerBounds(this.getLeftOperand()) and
-      rLower = getFullyConvertedLowerBounds(this.getRightOperand()) and
+      lLower = getFullyConvertedLowerBounds(getLeftOperand()) and
+      rLower = getFullyConvertedLowerBounds(getRightOperand()) and
       (
         (lLower < 0 or rLower < 0) and
         result = exprMinVal(this)
@@ -68,10 +68,10 @@ private class ConstantBitwiseAndExprRange extends SimpleRangeAnalysisExpr {
     // If an operand can have negative values, the upper bound is unconstrained.
     // Otherwise, the upper bound is the minimum of the upper bounds of the operands
     exists(float lLower, float lUpper, float rLower, float rUpper |
-      lLower = getFullyConvertedLowerBounds(this.getLeftOperand()) and
-      lUpper = getFullyConvertedUpperBounds(this.getLeftOperand()) and
-      rLower = getFullyConvertedLowerBounds(this.getRightOperand()) and
-      rUpper = getFullyConvertedUpperBounds(this.getRightOperand()) and
+      lLower = getFullyConvertedLowerBounds(getLeftOperand()) and
+      lUpper = getFullyConvertedUpperBounds(getLeftOperand()) and
+      rLower = getFullyConvertedLowerBounds(getRightOperand()) and
+      rUpper = getFullyConvertedUpperBounds(getRightOperand()) and
       (
         (lLower < 0 or rLower < 0) and
         result = exprMaxVal(this)
@@ -85,6 +85,6 @@ private class ConstantBitwiseAndExprRange extends SimpleRangeAnalysisExpr {
   }
 
   override predicate dependsOnChild(Expr child) {
-    child = this.getLeftOperand() or child = this.getRightOperand()
+    child = getLeftOperand() or child = getRightOperand()
   }
 }

cpp/ql/lib/experimental/semmle/code/cpp/rangeanalysis/extensions/ConstantShiftExprRange.qll

@@ -50,7 +50,7 @@ class ConstantRShiftExprRange extends SimpleRangeAnalysisExpr {
    * We don't handle the case where `a` and `b` are both non-constant values.
    */
   ConstantRShiftExprRange() {
-    this.getUnspecifiedType() instanceof IntegralType and
+    getUnspecifiedType() instanceof IntegralType and
     exists(Expr l, Expr r |
       l = this.(RShiftExpr).getLeftOperand() and
       r = this.(RShiftExpr).getRightOperand()
@@ -84,10 +84,10 @@ class ConstantRShiftExprRange extends SimpleRangeAnalysisExpr {
 
   override float getLowerBounds() {
     exists(int lLower, int lUpper, int rLower, int rUpper |
-      lLower = getFullyConvertedLowerBounds(this.getLeftOperand()) and
-      lUpper = getFullyConvertedUpperBounds(this.getLeftOperand()) and
-      rLower = getFullyConvertedLowerBounds(this.getRightOperand()) and
-      rUpper = getFullyConvertedUpperBounds(this.getRightOperand()) and
+      lLower = getFullyConvertedLowerBounds(getLeftOperand()) and
+      lUpper = getFullyConvertedUpperBounds(getLeftOperand()) and
+      rLower = getFullyConvertedLowerBounds(getRightOperand()) and
+      rUpper = getFullyConvertedUpperBounds(getRightOperand()) and
       lLower <= lUpper and
       rLower <= rUpper
     |
@@ -95,8 +95,8 @@ class ConstantRShiftExprRange extends SimpleRangeAnalysisExpr {
         lLower < 0
         or
         not (
-          isValidShiftExprShift(rLower, this.getLeftOperand()) and
-          isValidShiftExprShift(rUpper, this.getLeftOperand())
+          isValidShiftExprShift(rLower, getLeftOperand()) and
+          isValidShiftExprShift(rUpper, getLeftOperand())
         )
       then
         // We don't want to deal with shifting negative numbers at the moment,
@@ -111,10 +111,10 @@ class ConstantRShiftExprRange extends SimpleRangeAnalysisExpr {
 
   override float getUpperBounds() {
     exists(int lLower, int lUpper, int rLower, int rUpper |
-      lLower = getFullyConvertedLowerBounds(this.getLeftOperand()) and
-      lUpper = getFullyConvertedUpperBounds(this.getLeftOperand()) and
-      rLower = getFullyConvertedLowerBounds(this.getRightOperand()) and
-      rUpper = getFullyConvertedUpperBounds(this.getRightOperand()) and
+      lLower = getFullyConvertedLowerBounds(getLeftOperand()) and
+      lUpper = getFullyConvertedUpperBounds(getLeftOperand()) and
+      rLower = getFullyConvertedLowerBounds(getRightOperand()) and
+      rUpper = getFullyConvertedUpperBounds(getRightOperand()) and
       lLower <= lUpper and
       rLower <= rUpper
     |
@@ -122,8 +122,8 @@ class ConstantRShiftExprRange extends SimpleRangeAnalysisExpr {
         lLower < 0
         or
         not (
-          isValidShiftExprShift(rLower, this.getLeftOperand()) and
-          isValidShiftExprShift(rUpper, this.getLeftOperand())
+          isValidShiftExprShift(rLower, getLeftOperand()) and
+          isValidShiftExprShift(rUpper, getLeftOperand())
         )
       then
         // We don't want to deal with shifting negative numbers at the moment,
@@ -137,7 +137,7 @@ class ConstantRShiftExprRange extends SimpleRangeAnalysisExpr {
   }
 
   override predicate dependsOnChild(Expr child) {
-    child = this.getLeftOperand() or child = this.getRightOperand()
+    child = getLeftOperand() or child = getRightOperand()
   }
 }
 
@@ -163,7 +163,7 @@ class ConstantLShiftExprRange extends SimpleRangeAnalysisExpr {
    * We don't handle the case where `a` and `b` are both non-constant values.
    */
   ConstantLShiftExprRange() {
-    this.getUnspecifiedType() instanceof IntegralType and
+    getUnspecifiedType() instanceof IntegralType and
     exists(Expr l, Expr r |
       l = this.(LShiftExpr).getLeftOperand() and
       r = this.(LShiftExpr).getRightOperand()
@@ -197,10 +197,10 @@ class ConstantLShiftExprRange extends SimpleRangeAnalysisExpr {
 
   override float getLowerBounds() {
     exists(int lLower, int lUpper, int rLower, int rUpper |
-      lLower = getFullyConvertedLowerBounds(this.getLeftOperand()) and
-      lUpper = getFullyConvertedUpperBounds(this.getLeftOperand()) and
-      rLower = getFullyConvertedLowerBounds(this.getRightOperand()) and
-      rUpper = getFullyConvertedUpperBounds(this.getRightOperand()) and
+      lLower = getFullyConvertedLowerBounds(getLeftOperand()) and
+      lUpper = getFullyConvertedUpperBounds(getLeftOperand()) and
+      rLower = getFullyConvertedLowerBounds(getRightOperand()) and
+      rUpper = getFullyConvertedUpperBounds(getRightOperand()) and
       lLower <= lUpper and
       rLower <= rUpper
     |
@@ -208,8 +208,8 @@ class ConstantLShiftExprRange extends SimpleRangeAnalysisExpr {
         lLower < 0
         or
         not (
-          isValidShiftExprShift(rLower, this.getLeftOperand()) and
-          isValidShiftExprShift(rUpper, this.getLeftOperand())
+          isValidShiftExprShift(rLower, getLeftOperand()) and
+          isValidShiftExprShift(rUpper, getLeftOperand())
         )
       then
         // We don't want to deal with shifting negative numbers at the moment,
@@ -228,10 +228,10 @@ class ConstantLShiftExprRange extends SimpleRangeAnalysisExpr {
 
   override float getUpperBounds() {
     exists(int lLower, int lUpper, int rLower, int rUpper |
-      lLower = getFullyConvertedLowerBounds(this.getLeftOperand()) and
-      lUpper = getFullyConvertedUpperBounds(this.getLeftOperand()) and
-      rLower = getFullyConvertedLowerBounds(this.getRightOperand()) and
-      rUpper = getFullyConvertedUpperBounds(this.getRightOperand()) and
+      lLower = getFullyConvertedLowerBounds(getLeftOperand()) and
+      lUpper = getFullyConvertedUpperBounds(getLeftOperand()) and
+      rLower = getFullyConvertedLowerBounds(getRightOperand()) and
+      rUpper = getFullyConvertedUpperBounds(getRightOperand()) and
       lLower <= lUpper and
       rLower <= rUpper
     |
@@ -239,8 +239,8 @@ class ConstantLShiftExprRange extends SimpleRangeAnalysisExpr {
         lLower < 0
         or
         not (
-          isValidShiftExprShift(rLower, this.getLeftOperand()) and
-          isValidShiftExprShift(rUpper, this.getLeftOperand())
+          isValidShiftExprShift(rLower, getLeftOperand()) and
+          isValidShiftExprShift(rUpper, getLeftOperand())
         )
       then
         // We don't want to deal with shifting negative numbers at the moment,
@@ -258,6 +258,6 @@ class ConstantLShiftExprRange extends SimpleRangeAnalysisExpr {
   }
 
   override predicate dependsOnChild(Expr child) {
-    child = this.getLeftOperand() or child = this.getRightOperand()
+    child = getLeftOperand() or child = getRightOperand()
   }
 }

cpp/ql/lib/experimental/semmle/code/cpp/rangeanalysis/extensions/RangeNode.qll

@@ -83,23 +83,20 @@ private class ExprRangeNode extends DataFlow::ExprNode {
   private string getCallBounds(Call e) {
     result =
       getExprBoundAsString(e) + "(" +
-        concat(Expr arg, int i |
-          arg = e.getArgument(i)
-        |
-          this.getIntegralBounds(arg), "," order by i
-        ) + ")"
+        concat(Expr arg, int i | arg = e.getArgument(i) | getIntegralBounds(arg) order by i, ",") +
+        ")"
   }
 
   override string toString() {
-    exists(Expr e | e = this.getExpr() |
+    exists(Expr e | e = getExpr() |
       if hasIntegralOrReferenceIntegralType(e)
       then
-        result = super.toString() + ": " + this.getOperationBounds(e)
+        result = super.toString() + ": " + getOperationBounds(e)
         or
-        result = super.toString() + ": " + this.getCallBounds(e)
+        result = super.toString() + ": " + getCallBounds(e)
         or
-        not exists(this.getOperationBounds(e)) and
-        not exists(this.getCallBounds(e)) and
+        not exists(getOperationBounds(e)) and
+        not exists(getCallBounds(e)) and
         result = super.toString() + ": " + getExprBoundAsString(e)
       else result = super.toString()
     )
@@ -111,8 +108,8 @@ private class ExprRangeNode extends DataFlow::ExprNode {
  */
 private class ReferenceArgumentRangeNode extends DataFlow::DefinitionByReferenceNode {
   override string toString() {
-    if hasIntegralOrReferenceIntegralType(this.asDefiningArgument())
-    then result = super.toString() + ": " + getExprBoundAsString(this.getArgument())
+    if hasIntegralOrReferenceIntegralType(asDefiningArgument())
+    then result = super.toString() + ": " + getExprBoundAsString(getArgument())
     else result = super.toString()
   }
 }

cpp/ql/lib/experimental/semmle/code/cpp/rangeanalysis/extensions/StrlenLiteralRangeExpr.qll

@@ -7,12 +7,12 @@ private import experimental.semmle.code.cpp.models.interfaces.SimpleRangeAnalysi
  */
 class StrlenLiteralRangeExpr extends SimpleRangeAnalysisExpr, FunctionCall {
   StrlenLiteralRangeExpr() {
-    this.getTarget().hasGlobalOrStdName("strlen") and this.getArgument(0).isConstant()
+    getTarget().hasGlobalOrStdName("strlen") and getArgument(0).isConstant()
   }
 
-  override int getLowerBounds() { result = this.getArgument(0).getValue().length() }
+  override int getLowerBounds() { result = getArgument(0).getValue().length() }
 
-  override int getUpperBounds() { result = this.getArgument(0).getValue().length() }
+  override int getUpperBounds() { result = getArgument(0).getValue().length() }
 
   override predicate dependsOnChild(Expr e) { none() }
 }

cpp/ql/lib/experimental/semmle/code/cpp/rangeanalysis/extensions/SubtractSelf.qll

@@ -3,8 +3,8 @@ import experimental.semmle.code.cpp.models.interfaces.SimpleRangeAnalysisExpr
 private class SelfSub extends SimpleRangeAnalysisExpr, SubExpr {
   SelfSub() {
     // Match `x - x` but not `myInt - (unsigned char)myInt`.
-    this.getLeftOperand().getExplicitlyConverted().(VariableAccess).getTarget() =
-      this.getRightOperand().getExplicitlyConverted().(VariableAccess).getTarget()
+    getLeftOperand().getExplicitlyConverted().(VariableAccess).getTarget() =
+      getRightOperand().getExplicitlyConverted().(VariableAccess).getTarget()
   }
 
   override float getLowerBounds() { result = 0 }

cpp/ql/lib/qlpack.yml

@@ -1,5 +1,5 @@
 name: codeql/cpp-all
-version: 0.8.1
+version: 0.7.1-dev
 groups: cpp
 dbscheme: semmlecode.cpp.dbscheme
 extractor: cpp
@@ -9,4 +9,3 @@ dependencies:
   codeql/ssa: ${workspace}
   codeql/tutorial: ${workspace}
   codeql/util: ${workspace}
-warnOnImplicitThis: true

cpp/ql/lib/semmle/code/cpp/Class.qll

@@ -176,6 +176,20 @@ class Class extends UserType {
   /** Holds if this class, struct or union has a constructor. */
   predicate hasConstructor() { exists(this.getAConstructor()) }
 
+  /**
+   * Holds if this class has a copy constructor that is either explicitly
+   * declared (though possibly `= delete`) or is auto-generated, non-trivial
+   * and called from somewhere.
+   *
+   * DEPRECATED: There is more than one reasonable definition of what it means
+   * to have a copy constructor, and we do not want to promote one particular
+   * definition by naming it with this predicate. Having a copy constructor
+   * could mean that such a member is declared or defined in the source or that
+   * it is callable by a particular caller. For C++11, there's also a question
+   * of whether to include members that are defaulted or deleted.
+   */
+  deprecated predicate hasCopyConstructor() { this.getAMemberFunction() instanceof CopyConstructor }
+
   /**
    * Like accessOfBaseMember but returns multiple results if there are multiple
    * paths to `base` through the inheritance graph.

cpp/ql/lib/semmle/code/cpp/Compilation.qll

@@ -42,7 +42,7 @@ class Compilation extends @compilation {
   }
 
   /** Gets a file compiled during this invocation. */
-  File getAFileCompiled() { result = this.getFileCompiled(_) }
+  File getAFileCompiled() { result = getFileCompiled(_) }
 
   /** Gets the `i`th file compiled during this invocation */
   File getFileCompiled(int i) { compilation_compiling_files(this, i, unresolveElement(result)) }
@@ -74,7 +74,7 @@ class Compilation extends @compilation {
   /**
    * Gets an argument passed to the extractor on this invocation.
    */
-  string getAnArgument() { result = this.getArgument(_) }
+  string getAnArgument() { result = getArgument(_) }
 
   /**
    * Gets the `i`th argument passed to the extractor on this invocation.

cpp/ql/lib/semmle/code/cpp/Field.qll

@@ -39,8 +39,7 @@ class Field extends MemberVariable {
    * complete most-derived object.
    */
   int getAByteOffsetIn(Class mostDerivedClass) {
-    result =
-      mostDerivedClass.getABaseClassByteOffset(this.getDeclaringType()) + this.getByteOffset()
+    result = mostDerivedClass.getABaseClassByteOffset(getDeclaringType()) + getByteOffset()
   }
 
   /**
@@ -117,10 +116,10 @@ class BitField extends Field {
   int getBitOffset() { fieldoffsets(underlyingElement(this), _, result) }
 
   /** Holds if this bitfield is anonymous. */
-  predicate isAnonymous() { this.hasName("(unnamed bitfield)") }
+  predicate isAnonymous() { hasName("(unnamed bitfield)") }
 
   override predicate isInitializable() {
     // Anonymous bitfields are not initializable.
-    not this.isAnonymous()
+    not isAnonymous()
   }
 }

cpp/ql/lib/semmle/code/cpp/File.qll

@@ -34,6 +34,14 @@ class Container extends Locatable, @container {
    */
   string getAbsolutePath() { none() } // overridden by subclasses
 
+  /**
+   * DEPRECATED: Use `getLocation` instead.
+   * Gets a URL representing the location of this container.
+   *
+   * For more information see [Providing URLs](https://codeql.github.com/docs/writing-codeql-queries/providing-locations-in-codeql-queries/#providing-urls).
+   */
+  deprecated string getURL() { none() } // overridden by subclasses
+
   /**
    * Gets the relative path of this file or folder from the root folder of the
    * analyzed source location. The relative path of the root folder itself is
@@ -175,6 +183,12 @@ class Folder extends Container, @folder {
   }
 
   override string getAPrimaryQlClass() { result = "Folder" }
+
+  /**
+   * DEPRECATED: Use `getLocation` instead.
+   * Gets the URL of this folder.
+   */
+  deprecated override string getURL() { result = "file://" + this.getAbsolutePath() + ":0:0:0:0" }
 }
 
 /**
@@ -199,6 +213,12 @@ class File extends Container, @file {
     result.hasLocationInfo(_, 0, 0, 0, 0)
   }
 
+  /**
+   * DEPRECATED: Use `getLocation` instead.
+   * Gets the URL of this file.
+   */
+  deprecated override string getURL() { result = "file://" + this.getAbsolutePath() + ":0:0:0:0" }
+
   /** Holds if this file was compiled as C (at any point). */
   predicate compiledAsC() { fileannotations(underlyingElement(this), 1, "compiled as c", "1") }
 

cpp/ql/lib/semmle/code/cpp/Linkage.qll

@@ -24,10 +24,10 @@ class LinkTarget extends @link_target {
    * captured as part of the snapshot, then everything is grouped together
    * into a single dummy link target.
    */
-  predicate isDummy() { this.getBinary().getAbsolutePath() = "" }
+  predicate isDummy() { getBinary().getAbsolutePath() = "" }
 
   /** Gets a textual representation of this element. */
-  string toString() { result = this.getBinary().getAbsolutePath() }
+  string toString() { result = getBinary().getAbsolutePath() }
 
   /**
    * Gets a function which was compiled into this link target, or had its

cpp/ql/lib/semmle/code/cpp/Macro.qll

@@ -34,7 +34,7 @@ class Macro extends PreprocessorDirective, @ppd_define {
    * Gets the name of the macro.  For example, `MAX` in
    * `#define MAX(x,y) (((x)>(y))?(x):(y))`.
    */
-  string getName() { result = this.getHead().regexpCapture("([^(]*+).*", 1) }
+  string getName() { result = this.getHead().splitAt("(", 0) }
 
   /** Holds if the macro has name `name`. */
   predicate hasName(string name) { this.getName() = name }

cpp/ql/lib/semmle/code/cpp/NameQualifiers.qll

@@ -24,7 +24,7 @@ class NameQualifier extends NameQualifiableElement, @namequalifier {
    * Gets the expression ultimately qualified by the chain of name
    * qualifiers. For example, `f()` in `N1::N2::f()`.
    */
-  Expr getExpr() { result = this.getQualifiedElement+() }
+  Expr getExpr() { result = getQualifiedElement+() }
 
   /** Gets a location for this name qualifier. */
   override Location getLocation() { namequalifiers(underlyingElement(this), _, _, result) }
@@ -56,12 +56,12 @@ class NameQualifier extends NameQualifiableElement, @namequalifier {
       if nqe instanceof SpecialNameQualifyingElement
       then
         exists(Access a |
-          a = this.getQualifiedElement() and
+          a = getQualifiedElement() and
           result = a.getTarget().getDeclaringType()
         )
         or
         exists(FunctionCall c |
-          c = this.getQualifiedElement() and
+          c = getQualifiedElement() and
           result = c.getTarget().getDeclaringType()
         )
       else result = nqe
@@ -109,7 +109,7 @@ class NameQualifiableElement extends Element, @namequalifiableelement {
    * namespace.
    */
   predicate hasGlobalQualifiedName() {
-    this.getNameQualifier*().getQualifyingElement() instanceof GlobalNamespace
+    getNameQualifier*().getQualifyingElement() instanceof GlobalNamespace
   }
 
   /**
@@ -119,7 +119,7 @@ class NameQualifiableElement extends Element, @namequalifiableelement {
    */
   predicate hasSuperQualifiedName() {
     exists(NameQualifier nq, SpecialNameQualifyingElement snqe |
-      nq = this.getNameQualifier*() and
+      nq = getNameQualifier*() and
       namequalifiers(unresolveElement(nq), _, unresolveElement(snqe), _) and
       snqe.getName() = "__super"
     )
@@ -164,5 +164,5 @@ library class SpecialNameQualifyingElement extends NameQualifyingElement,
   /** Gets the name of this special qualifying element. */
   override string getName() { specialnamequalifyingelements(underlyingElement(this), result) }
 
-  override string toString() { result = this.getName() }
+  override string toString() { result = getName() }
 }

cpp/ql/lib/semmle/code/cpp/Namespace.qll

@@ -230,12 +230,8 @@ class GlobalNamespace extends Namespace {
 }
 
 /**
- * The C++ `std::` namespace and its inline namespaces.
+ * The C++ `std::` namespace.
  */
 class StdNamespace extends Namespace {
-  StdNamespace() {
-    this.hasName("std") and this.getParentNamespace() instanceof GlobalNamespace
-    or
-    this.isInline() and this.getParentNamespace() instanceof StdNamespace
-  }
+  StdNamespace() { this.hasName("std") and this.getParentNamespace() instanceof GlobalNamespace }
 }

cpp/ql/lib/semmle/code/cpp/NestedFields.qll

@@ -37,7 +37,7 @@ class NestedFieldAccess extends FieldAccess {
 
   NestedFieldAccess() {
     ultimateQualifier = getUltimateQualifier(this) and
-    this.getTarget() = getANestedField(ultimateQualifier.getType().stripType())
+    getTarget() = getANestedField(ultimateQualifier.getType().stripType())
   }
 
   /**

cpp/ql/lib/semmle/code/cpp/PrintAST.qll

@@ -27,6 +27,9 @@ class PrintAstConfiguration extends TPrintAstConfiguration {
   predicate shouldPrintFunction(Function func) { any() }
 }
 
+/** DEPRECATED: Alias for PrintAstConfiguration */
+deprecated class PrintASTConfiguration = PrintAstConfiguration;
+
 private predicate shouldPrintFunction(Function func) {
   exists(PrintAstConfiguration config | config.shouldPrintFunction(func))
 }
@@ -127,7 +130,7 @@ class PrintAstNode extends TPrintAstNode {
     // The exact value of `childIndex` doesn't matter, as long as we preserve the correct order.
     result =
       rank[childIndex](PrintAstNode child, int nonConvertedIndex, boolean isConverted |
-        this.childAndAccessorPredicate(child, _, nonConvertedIndex, isConverted)
+        childAndAccessorPredicate(child, _, nonConvertedIndex, isConverted)
       |
         // Unconverted children come first, then sort by original child index within each group.
         child order by isConverted, nonConvertedIndex
@@ -140,7 +143,7 @@ class PrintAstNode extends TPrintAstNode {
    */
   private PrintAstNode getConvertedChild(int childIndex) {
     exists(Expr expr |
-      expr = this.getChildInternal(childIndex).(AstNode).getAst() and
+      expr = getChildInternal(childIndex).(AstNode).getAst() and
       expr.getFullyConverted() instanceof Conversion and
       result.(AstNode).getAst() = expr.getFullyConverted() and
       not expr instanceof Conversion
@@ -152,8 +155,8 @@ class PrintAstNode extends TPrintAstNode {
    * at index `childIndex`, if that node has any conversions.
    */
   private string getConvertedChildAccessorPredicate(int childIndex) {
-    exists(this.getConvertedChild(childIndex)) and
-    result = this.getChildAccessorPredicateInternal(childIndex) + ".getFullyConverted()"
+    exists(getConvertedChild(childIndex)) and
+    result = getChildAccessorPredicateInternal(childIndex) + ".getFullyConverted()"
   }
 
   /**
@@ -161,12 +164,12 @@ class PrintAstNode extends TPrintAstNode {
    * within a function are printed, but the query can override
    * `PrintASTConfiguration.shouldPrintFunction` to filter the output.
    */
-  final predicate shouldPrint() { shouldPrintFunction(this.getEnclosingFunction()) }
+  final predicate shouldPrint() { shouldPrintFunction(getEnclosingFunction()) }
 
   /**
    * Gets the children of this node.
    */
-  final PrintAstNode getAChild() { result = this.getChild(_) }
+  final PrintAstNode getAChild() { result = getChild(_) }
 
   /**
    * Gets the parent of this node, if any.
@@ -184,7 +187,7 @@ class PrintAstNode extends TPrintAstNode {
    */
   string getProperty(string key) {
     key = "semmle.label" and
-    result = this.toString()
+    result = toString()
   }
 
   /**
@@ -198,12 +201,12 @@ class PrintAstNode extends TPrintAstNode {
   private predicate childAndAccessorPredicate(
     PrintAstNode child, string childPredicate, int nonConvertedIndex, boolean isConverted
   ) {
-    child = this.getChildInternal(nonConvertedIndex) and
-    childPredicate = this.getChildAccessorPredicateInternal(nonConvertedIndex) and
+    child = getChildInternal(nonConvertedIndex) and
+    childPredicate = getChildAccessorPredicateInternal(nonConvertedIndex) and
     isConverted = false
     or
-    child = this.getConvertedChild(nonConvertedIndex) and
-    childPredicate = this.getConvertedChildAccessorPredicate(nonConvertedIndex) and
+    child = getConvertedChild(nonConvertedIndex) and
+    childPredicate = getConvertedChildAccessorPredicate(nonConvertedIndex) and
     isConverted = true
   }
 
@@ -215,7 +218,7 @@ class PrintAstNode extends TPrintAstNode {
     // The exact value of `childIndex` doesn't matter, as long as we preserve the correct order.
     result =
       rank[childIndex](string childPredicate, int nonConvertedIndex, boolean isConverted |
-        this.childAndAccessorPredicate(_, childPredicate, nonConvertedIndex, isConverted)
+        childAndAccessorPredicate(_, childPredicate, nonConvertedIndex, isConverted)
       |
         // Unconverted children come first, then sort by original child index within each group.
         childPredicate order by isConverted, nonConvertedIndex
@@ -231,11 +234,12 @@ class PrintAstNode extends TPrintAstNode {
   /**
    * Gets the `Function` that contains this node.
    */
-  private Function getEnclosingFunction() {
-    result = this.getParent*().(FunctionNode).getFunction()
-  }
+  private Function getEnclosingFunction() { result = getParent*().(FunctionNode).getFunction() }
 }
 
+/** DEPRECATED: Alias for PrintAstNode */
+deprecated class PrintASTNode = PrintAstNode;
+
 /**
  * Class that restricts the elements that we compute `qlClass` for.
  */
@@ -249,7 +253,7 @@ private class PrintableElement extends Element {
   }
 
   pragma[noinline]
-  string getAPrimaryQlClass0() { result = this.getAPrimaryQlClass() }
+  string getAPrimaryQlClass0() { result = getAPrimaryQlClass() }
 }
 
 /**
@@ -277,9 +281,12 @@ abstract class BaseAstNode extends PrintAstNode {
   final Locatable getAst() { result = ast }
 
   /** DEPRECATED: Alias for getAst */
-  deprecated Locatable getAST() { result = this.getAst() }
+  deprecated Locatable getAST() { result = getAst() }
 }
 
+/** DEPRECATED: Alias for BaseAstNode */
+deprecated class BaseASTNode = BaseAstNode;
+
 /**
  * A node representing an AST node other than a `DeclarationEntry`.
  */
@@ -287,6 +294,9 @@ abstract class AstNode extends BaseAstNode, TAstNode {
   AstNode() { this = TAstNode(ast) }
 }
 
+/** DEPRECATED: Alias for AstNode */
+deprecated class ASTNode = AstNode;
+
 /**
  * A node representing an `Expr`.
  */
@@ -301,7 +311,7 @@ class ExprNode extends AstNode {
     result = super.getProperty(key)
     or
     key = "Value" and
-    result = qlClass(expr) + this.getValue()
+    result = qlClass(expr) + getValue()
     or
     key = "Type" and
     result = qlClass(expr.getType()) + expr.getType().toString()
@@ -311,7 +321,7 @@ class ExprNode extends AstNode {
   }
 
   override string getChildAccessorPredicateInternal(int childIndex) {
-    result = getChildAccessorWithoutConversions(ast, this.getChildInternal(childIndex).getAst())
+    result = getChildAccessorWithoutConversions(ast, getChildInternal(childIndex).getAst())
   }
 
   /**
@@ -431,7 +441,7 @@ class StmtNode extends AstNode {
   }
 
   override string getChildAccessorPredicateInternal(int childIndex) {
-    result = getChildAccessorWithoutConversions(ast, this.getChildInternal(childIndex).getAst())
+    result = getChildAccessorWithoutConversions(ast, getChildInternal(childIndex).getAst())
   }
 }
 
@@ -507,7 +517,7 @@ class ParametersNode extends PrintAstNode, TParametersNode {
   }
 
   override string getChildAccessorPredicateInternal(int childIndex) {
-    exists(this.getChildInternal(childIndex)) and
+    exists(getChildInternal(childIndex)) and
     result = "getParameter(" + childIndex.toString() + ")"
   }
 
@@ -534,7 +544,7 @@ class ConstructorInitializersNode extends PrintAstNode, TConstructorInitializers
   }
 
   final override string getChildAccessorPredicateInternal(int childIndex) {
-    exists(this.getChildInternal(childIndex)) and
+    exists(getChildInternal(childIndex)) and
     result = "getInitializer(" + childIndex.toString() + ")"
   }
 
@@ -561,7 +571,7 @@ class DestructorDestructionsNode extends PrintAstNode, TDestructorDestructionsNo
   }
 
   final override string getChildAccessorPredicateInternal(int childIndex) {
-    exists(this.getChildInternal(childIndex)) and
+    exists(getChildInternal(childIndex)) and
     result = "getDestruction(" + childIndex.toString() + ")"
   }
 
@@ -618,7 +628,7 @@ class FunctionNode extends AstNode {
   override string getProperty(string key) {
     result = super.getProperty(key)
     or
-    key = "semmle.order" and result = this.getOrder().toString()
+    key = "semmle.order" and result = getOrder().toString()
   }
 
   /**
@@ -741,8 +751,6 @@ private predicate namedExprChildPredicates(Expr expr, Element ele, string pred)
     or
     expr.(VariableAccess).getQualifier() = ele and pred = "getQualifier()"
     or
-    expr.(FunctionAccess).getQualifier() = ele and pred = "getQualifier()"
-    or
     exists(Field f |
       expr.(ClassAggregateLiteral).getAFieldExpr(f) = ele and
       pred = "getAFieldExpr(" + f.toString() + ")"

cpp/ql/lib/semmle/code/cpp/Type.qll

@@ -1699,28 +1699,7 @@ class AutoType extends TemplateParameter {
 
 private predicate suppressUnusedThis(Type t) { any() }
 
-/**
- * A source code location referring to a user-defined type.
- *
- * Note that only _user-defined_ types have `TypeMention`s. In particular,
- * built-in types, and derived types with built-in types as their base don't
- * have any `TypeMention`s. For example, given
- * ```cpp
- * struct S { ... };
- * void f(S s1, int i1) {
- *   S s2;
- *   S* s3;
- *   S& s4 = s2;
- *   decltype(s2) s5;
- *
- *   int i2;
- *   int* i3;
- *   int i4[10];
- * }
- * ```
- * there will be a `TypeMention` for the mention of `S` at `S s1`, `S s2`, and `S& s4 = s2`,
- * but not at `decltype(s2) s5`. Additionally, there will be no `TypeMention`s for `int`.
- */
+/** A source code location referring to a type */
 class TypeMention extends Locatable, @type_mention {
   override string toString() { result = "type mention" }
 

cpp/ql/lib/semmle/code/cpp/commons/Strcat.qll

@@ -8,7 +8,7 @@ import cpp
  */
 deprecated class StrcatFunction extends Function {
   StrcatFunction() {
-    this.getName() =
+    getName() =
       [
         "strcat", // strcat(dst, src)
         "strncat", // strncat(dst, src, max_amount)

cpp/ql/lib/semmle/code/cpp/controlflow/DefinitionsAndUses.qll

@@ -98,7 +98,7 @@ library class DefOrUse extends ControlFlowNodeBase {
 
   pragma[noinline]
   private predicate reaches_helper(boolean isDef, SemanticStackVariable v, BasicBlock bb, int i) {
-    this.getVariable(isDef) = v and
+    getVariable(isDef) = v and
     bb.getNode(i) = this
   }
 
@@ -118,21 +118,21 @@ library class DefOrUse extends ControlFlowNodeBase {
      * predicates are duplicated for now.
      */
 
-    exists(BasicBlock bb, int i | this.reaches_helper(isDef, v, bb, i) |
+    exists(BasicBlock bb, int i | reaches_helper(isDef, v, bb, i) |
       exists(int j |
         j > i and
         (bbDefAt(bb, j, v, defOrUse) or bbUseAt(bb, j, v, defOrUse)) and
-        not exists(int k | this.firstBarrierAfterThis(isDef, k, v) and k < j)
+        not exists(int k | firstBarrierAfterThis(isDef, k, v) and k < j)
       )
       or
-      not this.firstBarrierAfterThis(isDef, _, v) and
+      not firstBarrierAfterThis(isDef, _, v) and
       bbSuccessorEntryReachesDefOrUse(bb, v, defOrUse, _)
     )
   }
 
   private predicate firstBarrierAfterThis(boolean isDef, int j, SemanticStackVariable v) {
     exists(BasicBlock bb, int i |
-      this.getVariable(isDef) = v and
+      getVariable(isDef) = v and
       bb.getNode(i) = this and
       j = min(int k | bbBarrierAt(bb, k, v, _) and k > i)
     )

cpp/ql/lib/semmle/code/cpp/controlflow/IRGuards.qll

@@ -627,20 +627,6 @@ private predicate sub_lt(
     x = int_value(rhs.getRight()) and
     k = c - x
   )
-  or
-  exists(PointerSubInstruction lhs, int c, int x |
-    compares_lt(cmp, lhs.getAUse(), right, c, isLt, testIsTrue) and
-    left = lhs.getLeftOperand() and
-    x = int_value(lhs.getRight()) and
-    k = c + x
-  )
-  or
-  exists(PointerSubInstruction rhs, int c, int x |
-    compares_lt(cmp, left, rhs.getAUse(), c, isLt, testIsTrue) and
-    right = rhs.getLeftOperand() and
-    x = int_value(rhs.getRight()) and
-    k = c - x
-  )
 }
 
 // left + x < right + c => left < right + (c-x)
@@ -667,26 +653,6 @@ private predicate add_lt(
     ) and
     k = c + x
   )
-  or
-  exists(PointerAddInstruction lhs, int c, int x |
-    compares_lt(cmp, lhs.getAUse(), right, c, isLt, testIsTrue) and
-    (
-      left = lhs.getLeftOperand() and x = int_value(lhs.getRight())
-      or
-      left = lhs.getRightOperand() and x = int_value(lhs.getLeft())
-    ) and
-    k = c - x
-  )
-  or
-  exists(PointerAddInstruction rhs, int c, int x |
-    compares_lt(cmp, left, rhs.getAUse(), c, isLt, testIsTrue) and
-    (
-      right = rhs.getLeftOperand() and x = int_value(rhs.getRight())
-      or
-      right = rhs.getRightOperand() and x = int_value(rhs.getLeft())
-    ) and
-    k = c + x
-  )
 }
 
 // left - x == right + c => left == right + (c+x)
@@ -707,20 +673,6 @@ private predicate sub_eq(
     x = int_value(rhs.getRight()) and
     k = c - x
   )
-  or
-  exists(PointerSubInstruction lhs, int c, int x |
-    compares_eq(cmp, lhs.getAUse(), right, c, areEqual, testIsTrue) and
-    left = lhs.getLeftOperand() and
-    x = int_value(lhs.getRight()) and
-    k = c + x
-  )
-  or
-  exists(PointerSubInstruction rhs, int c, int x |
-    compares_eq(cmp, left, rhs.getAUse(), c, areEqual, testIsTrue) and
-    right = rhs.getLeftOperand() and
-    x = int_value(rhs.getRight()) and
-    k = c - x
-  )
 }
 
 // left + x == right + c => left == right + (c-x)
@@ -747,26 +699,6 @@ private predicate add_eq(
     ) and
     k = c + x
   )
-  or
-  exists(PointerAddInstruction lhs, int c, int x |
-    compares_eq(cmp, lhs.getAUse(), right, c, areEqual, testIsTrue) and
-    (
-      left = lhs.getLeftOperand() and x = int_value(lhs.getRight())
-      or
-      left = lhs.getRightOperand() and x = int_value(lhs.getLeft())
-    ) and
-    k = c - x
-  )
-  or
-  exists(PointerAddInstruction rhs, int c, int x |
-    compares_eq(cmp, left, rhs.getAUse(), c, areEqual, testIsTrue) and
-    (
-      right = rhs.getLeftOperand() and x = int_value(rhs.getRight())
-      or
-      right = rhs.getRightOperand() and x = int_value(rhs.getLeft())
-    ) and
-    k = c + x
-  )
 }
 
 /** The int value of integer constant expression. */

cpp/ql/lib/semmle/code/cpp/controlflow/SSA.qll

@@ -14,6 +14,9 @@ library class StandardSsa extends SsaHelper {
   StandardSsa() { this = 0 }
 }
 
+/** DEPRECATED: Alias for StandardSsa */
+deprecated class StandardSSA = StandardSsa;
+
 /**
  * A definition of one or more SSA variables, including phi node definitions.
  * An _SSA variable_, as defined in the literature, is effectively the pair of

cpp/ql/lib/semmle/code/cpp/controlflow/SSAUtils.qll

@@ -130,7 +130,7 @@ library class SsaHelper extends int {
    * Remove any custom phi nodes that are invalid.
    */
   private predicate sanitized_custom_phi_node(StackVariable v, BasicBlock b) {
-    this.custom_phi_node(v, b) and
+    custom_phi_node(v, b) and
     not addressTakenVariable(v) and
     not isReferenceVar(v) and
     b.isReachable()
@@ -142,7 +142,7 @@ library class SsaHelper extends int {
    */
   cached
   predicate phi_node(StackVariable v, BasicBlock b) {
-    this.frontier_phi_node(v, b) or this.sanitized_custom_phi_node(v, b)
+    frontier_phi_node(v, b) or sanitized_custom_phi_node(v, b)
   }
 
   /**
@@ -154,15 +154,14 @@ library class SsaHelper extends int {
    */
   private predicate frontier_phi_node(StackVariable v, BasicBlock b) {
     exists(BasicBlock x |
-      dominanceFrontier(x, b) and
-      this.ssa_defn_rec(pragma[only_bind_into](v), pragma[only_bind_into](x))
+      dominanceFrontier(x, b) and ssa_defn_rec(pragma[only_bind_into](v), pragma[only_bind_into](x))
     ) and
     /* We can also eliminate those nodes where the variable is not live on any incoming edge */
     live_at_start_of_bb(pragma[only_bind_into](v), b)
   }
 
   private predicate ssa_defn_rec(StackVariable v, BasicBlock b) {
-    this.phi_node(v, b)
+    phi_node(v, b)
     or
     variableUpdate(v, _, b, _)
   }
@@ -173,7 +172,7 @@ library class SsaHelper extends int {
    */
   cached
   predicate ssa_defn(StackVariable v, ControlFlowNode node, BasicBlock b, int index) {
-    this.phi_node(v, b) and b.getStart() = node and index = -1
+    phi_node(v, b) and b.getStart() = node and index = -1
     or
     variableUpdate(v, node, b, index)
   }
@@ -197,7 +196,7 @@ library class SsaHelper extends int {
    * basic blocks.
    */
   private predicate defUseRank(StackVariable v, BasicBlock b, int rankix, int i) {
-    i = rank[rankix](int j | this.ssa_defn(v, _, b, j) or ssa_use(v, _, b, j))
+    i = rank[rankix](int j | ssa_defn(v, _, b, j) or ssa_use(v, _, b, j))
   }
 
   /**
@@ -207,7 +206,7 @@ library class SsaHelper extends int {
    * the block.
    */
   private int lastRank(StackVariable v, BasicBlock b) {
-    result = max(int rankix | this.defUseRank(v, b, rankix, _)) + 1
+    result = max(int rankix | defUseRank(v, b, rankix, _)) + 1
   }
 
   /**
@@ -216,8 +215,8 @@ library class SsaHelper extends int {
    */
   private predicate ssaDefRank(StackVariable v, ControlFlowNode def, BasicBlock b, int rankix) {
     exists(int i |
-      this.ssa_defn(v, def, b, i) and
-      this.defUseRank(v, b, rankix, i)
+      ssa_defn(v, def, b, i) and
+      defUseRank(v, b, rankix, i)
     )
   }
 
@@ -233,21 +232,21 @@ library class SsaHelper extends int {
     // use is understood to happen _before_ the definition. Phi nodes are
     // at rankidx -1 and will therefore always reach the first node in the
     // basic block.
-    this.ssaDefRank(v, def, b, rankix - 1)
+    ssaDefRank(v, def, b, rankix - 1)
     or
-    this.ssaDefReachesRank(v, def, b, rankix - 1) and
-    rankix <= this.lastRank(v, b) and // Without this, the predicate would be infinite.
-    not this.ssaDefRank(v, _, b, rankix - 1) // Range is inclusive of but not past next def.
+    ssaDefReachesRank(v, def, b, rankix - 1) and
+    rankix <= lastRank(v, b) and // Without this, the predicate would be infinite.
+    not ssaDefRank(v, _, b, rankix - 1) // Range is inclusive of but not past next def.
   }
 
   /** Holds if SSA variable `(v, def)` reaches the end of block `b`. */
   cached
   predicate ssaDefinitionReachesEndOfBB(StackVariable v, ControlFlowNode def, BasicBlock b) {
-    live_at_exit_of_bb(v, b) and this.ssaDefReachesRank(v, def, b, this.lastRank(v, b))
+    live_at_exit_of_bb(v, b) and ssaDefReachesRank(v, def, b, lastRank(v, b))
     or
     exists(BasicBlock idom |
-      this.ssaDefinitionReachesEndOfBB(v, def, idom) and
-      this.noDefinitionsSinceIDominator(v, idom, b)
+      ssaDefinitionReachesEndOfBB(v, def, idom) and
+      noDefinitionsSinceIDominator(v, idom, b)
     )
   }
 
@@ -261,7 +260,7 @@ library class SsaHelper extends int {
   private predicate noDefinitionsSinceIDominator(StackVariable v, BasicBlock idom, BasicBlock b) {
     bbIDominates(idom, b) and // It is sufficient to traverse the dominator graph, cf. discussion above.
     live_at_exit_of_bb(v, b) and
-    not this.ssa_defn(v, _, b, _)
+    not ssa_defn(v, _, b, _)
   }
 
   /**
@@ -270,8 +269,8 @@ library class SsaHelper extends int {
    */
   private predicate ssaDefinitionReachesUseWithinBB(StackVariable v, ControlFlowNode def, Expr use) {
     exists(BasicBlock b, int rankix, int i |
-      this.ssaDefReachesRank(v, def, b, rankix) and
-      this.defUseRank(v, b, rankix, i) and
+      ssaDefReachesRank(v, def, b, rankix) and
+      defUseRank(v, b, rankix, i) and
       ssa_use(v, use, b, i)
     )
   }
@@ -280,12 +279,12 @@ library class SsaHelper extends int {
    * Holds if SSA variable `(v, def)` reaches the control-flow node `use`.
    */
   private predicate ssaDefinitionReaches(StackVariable v, ControlFlowNode def, Expr use) {
-    this.ssaDefinitionReachesUseWithinBB(v, def, use)
+    ssaDefinitionReachesUseWithinBB(v, def, use)
     or
     exists(BasicBlock b |
       ssa_use(v, use, b, _) and
-      this.ssaDefinitionReachesEndOfBB(v, def, b.getAPredecessor()) and
-      not this.ssaDefinitionReachesUseWithinBB(v, _, use)
+      ssaDefinitionReachesEndOfBB(v, def, b.getAPredecessor()) and
+      not ssaDefinitionReachesUseWithinBB(v, _, use)
     )
   }
 
@@ -295,10 +294,10 @@ library class SsaHelper extends int {
    */
   cached
   string toString(ControlFlowNode node, StackVariable v) {
-    if this.phi_node(v, node)
+    if phi_node(v, node)
     then result = "SSA phi(" + v.getName() + ")"
     else (
-      this.ssa_defn(v, node, _, _) and result = "SSA def(" + v.getName() + ")"
+      ssa_defn(v, node, _, _) and result = "SSA def(" + v.getName() + ")"
     )
   }
 
@@ -308,7 +307,10 @@ library class SsaHelper extends int {
    */
   cached
   VariableAccess getAUse(ControlFlowNode def, StackVariable v) {
-    this.ssaDefinitionReaches(v, def, result) and
+    ssaDefinitionReaches(v, def, result) and
     ssa_use(v, result, _, _)
   }
 }
+
+/** DEPRECATED: Alias for SsaHelper */
+deprecated class SSAHelper = SsaHelper;

cpp/ql/lib/semmle/code/cpp/controlflow/StackVariableReachability.qll

@@ -25,7 +25,7 @@ import cpp
  */
 abstract class StackVariableReachability extends string {
   bindingset[this]
-  StackVariableReachability() { this.length() >= 0 }
+  StackVariableReachability() { length() >= 0 }
 
   /** Holds if `node` is a source for the reachability analysis using variable `v`. */
   abstract predicate isSource(ControlFlowNode node, StackVariable v);
@@ -227,7 +227,7 @@ predicate bbSuccessorEntryReachesLoopInvariant(
  */
 abstract class StackVariableReachabilityWithReassignment extends StackVariableReachability {
   bindingset[this]
-  StackVariableReachabilityWithReassignment() { this.length() >= 0 }
+  StackVariableReachabilityWithReassignment() { length() >= 0 }
 
   /** Override this predicate rather than `isSource` (`isSource` is used internally). */
   abstract predicate isSourceActual(ControlFlowNode node, StackVariable v);
@@ -330,7 +330,7 @@ abstract class StackVariableReachabilityWithReassignment extends StackVariableRe
  */
 abstract class StackVariableReachabilityExt extends string {
   bindingset[this]
-  StackVariableReachabilityExt() { this.length() >= 0 }
+  StackVariableReachabilityExt() { length() >= 0 }
 
   /** `node` is a source for the reachability analysis using variable `v`. */
   abstract predicate isSource(ControlFlowNode node, StackVariable v);

cpp/ql/lib/semmle/code/cpp/controlflow/internal/CFG.qll

@@ -1385,6 +1385,9 @@ private module Cached {
     conditionalSuccessor(n1, _, n2)
   }
 
+  /** DEPRECATED: Alias for qlCfgSuccessor */
+  deprecated predicate qlCFGSuccessor = qlCfgSuccessor/2;
+
   /**
    * Holds if `n2` is a control-flow node such that the control-flow
    * edge `(n1, n2)` may be taken when `n1` is an expression that is true.
@@ -1395,6 +1398,9 @@ private module Cached {
     not conditionalSuccessor(n1, false, n2)
   }
 
+  /** DEPRECATED: Alias for qlCfgTrueSuccessor */
+  deprecated predicate qlCFGTrueSuccessor = qlCfgTrueSuccessor/2;
+
   /**
    * Holds if `n2` is a control-flow node such that the control-flow
    * edge `(n1, n2)` may be taken when `n1` is an expression that is false.
@@ -1404,4 +1410,7 @@ private module Cached {
     conditionalSuccessor(n1, false, n2) and
     not conditionalSuccessor(n1, true, n2)
   }
+
+  /** DEPRECATED: Alias for qlCfgFalseSuccessor */
+  deprecated predicate qlCFGFalseSuccessor = qlCfgFalseSuccessor/2;
 }

cpp/ql/lib/semmle/code/cpp/dataflow/DataFlow.qll

@@ -20,12 +20,10 @@
 import cpp
 
 /**
- * DEPRECATED: Use `semmle.code.cpp.dataflow.new.DataFlow` instead.
- *
  * Provides classes for performing local (intra-procedural) and
  * global (inter-procedural) data flow analyses.
  */
-deprecated module DataFlow {
+module DataFlow {
   import semmle.code.cpp.dataflow.internal.DataFlow
   import semmle.code.cpp.dataflow.internal.DataFlowImpl1
 }

cpp/ql/lib/semmle/code/cpp/dataflow/DataFlow2.qll

@@ -12,11 +12,9 @@
 import cpp
 
 /**
- * DEPRECATED: Use `semmle.code.cpp.dataflow.new.DataFlow2` instead.
- *
  * Provides classes for performing local (intra-procedural) and
  * global (inter-procedural) data flow analyses.
  */
-deprecated module DataFlow2 {
+module DataFlow2 {
   import semmle.code.cpp.dataflow.internal.DataFlowImpl2
 }

cpp/ql/lib/semmle/code/cpp/dataflow/DataFlow3.qll

@@ -12,11 +12,9 @@
 import cpp
 
 /**
- * DEPRECATED: Use `semmle.code.cpp.dataflow.new.DataFlow3` instead.
- *
  * Provides classes for performing local (intra-procedural) and
  * global (inter-procedural) data flow analyses.
  */
-deprecated module DataFlow3 {
+module DataFlow3 {
   import semmle.code.cpp.dataflow.internal.DataFlowImpl3
 }

cpp/ql/lib/semmle/code/cpp/dataflow/DataFlow4.qll

@@ -12,11 +12,9 @@
 import cpp
 
 /**
- * DEPRECATED: Use `semmle.code.cpp.dataflow.new.DataFlow4` instead.
- *
  * Provides classes for performing local (intra-procedural) and
  * global (inter-procedural) data flow analyses.
  */
-deprecated module DataFlow4 {
+module DataFlow4 {
   import semmle.code.cpp.dataflow.internal.DataFlowImpl4
 }

cpp/ql/lib/semmle/code/cpp/dataflow/TaintTracking.qll

@@ -19,12 +19,10 @@ import semmle.code.cpp.dataflow.DataFlow
 import semmle.code.cpp.dataflow.DataFlow2
 
 /**
- * DEPRECATED: Use `semmle.code.cpp.dataflow.new.TaintTracking` instead.
- *
  * Provides classes for performing local (intra-procedural) and
  * global (inter-procedural) taint-tracking analyses.
  */
-deprecated module TaintTracking {
+module TaintTracking {
   import semmle.code.cpp.dataflow.internal.tainttracking1.TaintTracking
   import semmle.code.cpp.dataflow.internal.tainttracking1.TaintTrackingImpl
 }

cpp/ql/lib/semmle/code/cpp/dataflow/TaintTracking2.qll

@@ -12,11 +12,9 @@
  */
 
 /**
- * DEPRECATED: Use `semmle.code.cpp.dataflow.new.TaintTracking2` instead.
- *
  * Provides classes for performing local (intra-procedural) and
  * global (inter-procedural) taint-tracking analyses.
  */
-deprecated module TaintTracking2 {
+module TaintTracking2 {
   import semmle.code.cpp.dataflow.internal.tainttracking2.TaintTrackingImpl
 }

cpp/ql/lib/semmle/code/cpp/dataflow/internal/DataFlow.qll

@@ -46,14 +46,6 @@ signature module ConfigSig {
    */
   default predicate allowImplicitRead(Node node, ContentSet c) { none() }
 
-  /**
-   * Holds if `node` should never be skipped over in the `PathGraph` and in path
-   * explanations.
-   */
-  default predicate neverSkip(Node node) {
-    isAdditionalFlowStep(node, _) or isAdditionalFlowStep(_, node)
-  }
-
   /**
    * Gets the virtual dispatch branching limit when calculating field flow.
    * This can be overridden to a smaller value to improve performance (a
@@ -122,7 +114,7 @@ signature module StateConfigSig {
    * Holds if data flow through `node` is prohibited when the flow state is
    * `state`.
    */
-  default predicate isBarrier(Node node, FlowState state) { none() }
+  predicate isBarrier(Node node, FlowState state);
 
   /** Holds if data flow into `node` is prohibited. */
   default predicate isBarrierIn(Node node) { none() }
@@ -139,9 +131,7 @@ signature module StateConfigSig {
    * Holds if data may flow from `node1` to `node2` in addition to the normal data-flow steps.
    * This step is only applicable in `state1` and updates the flow state to `state2`.
    */
-  default predicate isAdditionalFlowStep(Node node1, FlowState state1, Node node2, FlowState state2) {
-    none()
-  }
+  predicate isAdditionalFlowStep(Node node1, FlowState state1, Node node2, FlowState state2);
 
   /**
    * Holds if an arbitrary number of implicit read steps of content `c` may be
@@ -149,17 +139,6 @@ signature module StateConfigSig {
    */
   default predicate allowImplicitRead(Node node, ContentSet c) { none() }
 
-  /**
-   * Holds if `node` should never be skipped over in the `PathGraph` and in path
-   * explanations.
-   */
-  default predicate neverSkip(Node node) {
-    isAdditionalFlowStep(node, _) or
-    isAdditionalFlowStep(_, node) or
-    isAdditionalFlowStep(node, _, _, _) or
-    isAdditionalFlowStep(_, _, node, _)
-  }
-
   /**
    * Gets the virtual dispatch branching limit when calculating field flow.
    * This can be overridden to a smaller value to improve performance (a
@@ -382,52 +361,3 @@ module MergePathGraph<
     }
   }
 }
-
-/**
- * Constructs a `PathGraph` from three `PathGraph`s by disjoint union.
- */
-module MergePathGraph3<
-  PathNodeSig PathNode1, PathNodeSig PathNode2, PathNodeSig PathNode3,
-  PathGraphSig<PathNode1> Graph1, PathGraphSig<PathNode2> Graph2, PathGraphSig<PathNode3> Graph3>
-{
-  private module MergedInner = MergePathGraph<PathNode1, PathNode2, Graph1, Graph2>;
-
-  private module Merged =
-    MergePathGraph<MergedInner::PathNode, PathNode3, MergedInner::PathGraph, Graph3>;
-
-  /** A node in a graph of path explanations that is formed by disjoint union of the three given graphs. */
-  class PathNode instanceof Merged::PathNode {
-    /** Gets this as a projection on the first given `PathGraph`. */
-    PathNode1 asPathNode1() { result = super.asPathNode1().asPathNode1() }
-
-    /** Gets this as a projection on the second given `PathGraph`. */
-    PathNode2 asPathNode2() { result = super.asPathNode1().asPathNode2() }
-
-    /** Gets this as a projection on the third given `PathGraph`. */
-    PathNode3 asPathNode3() { result = super.asPathNode2() }
-
-    /** Gets a textual representation of this element. */
-    string toString() { result = super.toString() }
-
-    /**
-     * Holds if this element is at the specified location.
-     * The location spans column `startcolumn` of line `startline` to
-     * column `endcolumn` of line `endline` in file `filepath`.
-     * For more information, see
-     * [Locations](https://codeql.github.com/docs/writing-codeql-queries/providing-locations-in-codeql-queries/).
-     */
-    predicate hasLocationInfo(
-      string filepath, int startline, int startcolumn, int endline, int endcolumn
-    ) {
-      super.hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
-    }
-
-    /** Gets the underlying `Node`. */
-    Node getNode() { result = super.getNode() }
-  }
-
-  /**
-   * Provides the query predicates needed to include a graph in a path-problem query.
-   */
-  module PathGraph = Merged::PathGraph;
-}

cpp/ql/lib/semmle/code/cpp/dataflow/internal/DataFlowImpl1.qll

@@ -313,8 +313,6 @@ private module Config implements FullStateConfigSig {
     any(Configuration config).allowImplicitRead(node, c)
   }
 
-  predicate neverSkip(Node node) { none() }
-
   int fieldFlowBranchLimit() { result = min(any(Configuration config).fieldFlowBranchLimit()) }
 
   FlowFeature getAFeature() { result = any(Configuration config).getAFeature() }

cpp/ql/lib/semmle/code/cpp/dataflow/internal/DataFlowImpl2.qll

@@ -313,8 +313,6 @@ private module Config implements FullStateConfigSig {
     any(Configuration config).allowImplicitRead(node, c)
   }
 
-  predicate neverSkip(Node node) { none() }
-
   int fieldFlowBranchLimit() { result = min(any(Configuration config).fieldFlowBranchLimit()) }
 
   FlowFeature getAFeature() { result = any(Configuration config).getAFeature() }

cpp/ql/lib/semmle/code/cpp/dataflow/internal/DataFlowImpl3.qll

@@ -313,8 +313,6 @@ private module Config implements FullStateConfigSig {
     any(Configuration config).allowImplicitRead(node, c)
   }
 
-  predicate neverSkip(Node node) { none() }
-
   int fieldFlowBranchLimit() { result = min(any(Configuration config).fieldFlowBranchLimit()) }
 
   FlowFeature getAFeature() { result = any(Configuration config).getAFeature() }

cpp/ql/lib/semmle/code/cpp/dataflow/internal/DataFlowImpl4.qll

@@ -313,8 +313,6 @@ private module Config implements FullStateConfigSig {
     any(Configuration config).allowImplicitRead(node, c)
   }
 
-  predicate neverSkip(Node node) { none() }
-
   int fieldFlowBranchLimit() { result = min(any(Configuration config).fieldFlowBranchLimit()) }
 
   FlowFeature getAFeature() { result = any(Configuration config).getAFeature() }

cpp/ql/lib/semmle/code/cpp/dataflow/internal/DataFlowImplCommon.qll

@@ -187,6 +187,7 @@ private module LambdaFlow {
     else any()
   }
 
+  pragma[assume_small_delta]
   pragma[nomagic]
   predicate revLambdaFlow0(
     DataFlowCall lambdaCall, LambdaCallKind kind, Node node, DataFlowType t, boolean toReturn,
@@ -273,6 +274,7 @@ private module LambdaFlow {
     )
   }
 
+  pragma[assume_small_delta]
   pragma[nomagic]
   predicate revLambdaFlowOut(
     DataFlowCall lambdaCall, LambdaCallKind kind, TReturnPositionSimple pos, DataFlowType t,
@@ -813,15 +815,7 @@ private module Cached {
     )
   }
 
-  /**
-   * Holds if data can flow from `node1` to `node2` via a direct assignment to
-   * `c`.
-   *
-   * This includes reverse steps through reads when the result of the read has
-   * been stored into, in order to handle cases like `x.f1.f2 = y`.
-   */
-  cached
-  predicate store(
+  private predicate store(
     Node node1, Content c, Node node2, DataFlowType contentType, DataFlowType containerType
   ) {
     exists(ContentSet cs |
@@ -829,6 +823,18 @@ private module Cached {
     )
   }
 
+  /**
+   * Holds if data can flow from `node1` to `node2` via a direct assignment to
+   * `f`.
+   *
+   * This includes reverse steps through reads when the result of the read has
+   * been stored into, in order to handle cases like `x.f1.f2 = y`.
+   */
+  cached
+  predicate store(Node node1, TypedContent tc, Node node2, DataFlowType contentType) {
+    store(node1, tc.getContent(), node2, contentType, tc.getContainerType())
+  }
+
   /**
    * Holds if data can flow from `fromNode` to `toNode` because they are the post-update
    * nodes of some function output and input respectively, where the output and input
@@ -926,15 +932,36 @@ private module Cached {
     TReturnCtxNoFlowThrough() or
     TReturnCtxMaybeFlowThrough(ReturnPosition pos)
 
+  cached
+  newtype TTypedContentApprox =
+    MkTypedContentApprox(ContentApprox c, DataFlowType t) {
+      exists(Content cont |
+        c = getContentApprox(cont) and
+        store(_, cont, _, _, t)
+      )
+    }
+
+  cached
+  newtype TTypedContent = MkTypedContent(Content c, DataFlowType t) { store(_, c, _, _, t) }
+
+  cached
+  TypedContent getATypedContent(TypedContentApprox c) {
+    exists(ContentApprox cls, DataFlowType t, Content cont |
+      c = MkTypedContentApprox(cls, pragma[only_bind_into](t)) and
+      result = MkTypedContent(cont, pragma[only_bind_into](t)) and
+      cls = getContentApprox(cont)
+    )
+  }
+
   cached
   newtype TAccessPathFront =
-    TFrontNil() or
-    TFrontHead(Content c)
+    TFrontNil(DataFlowType t) or
+    TFrontHead(TypedContent tc)
 
   cached
   newtype TApproxAccessPathFront =
-    TApproxFrontNil() or
-    TApproxFrontHead(ContentApprox c)
+    TApproxFrontNil(DataFlowType t) or
+    TApproxFrontHead(TypedContentApprox tc)
 
   cached
   newtype TAccessPathFrontOption =
@@ -959,16 +986,8 @@ predicate recordDataFlowCallSite(DataFlowCall call, DataFlowCallable callable) {
 /**
  * A `Node` at which a cast can occur such that the type should be checked.
  */
-class CastingNode instanceof Node {
+class CastingNode extends Node {
   CastingNode() { castingNode(this) }
-
-  string toString() { result = super.toString() }
-
-  predicate hasLocationInfo(
-    string filepath, int startline, int startcolumn, int endline, int endcolumn
-  ) {
-    super.hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
-  }
 }
 
 private predicate readStepWithTypes(
@@ -1116,17 +1135,9 @@ LocalCallContext getLocalCallContext(CallContext ctx, DataFlowCallable callable)
  * The value of a parameter at function entry, viewed as a node in a data
  * flow graph.
  */
-class ParamNode instanceof Node {
+class ParamNode extends Node {
   ParamNode() { parameterNode(this, _, _) }
 
-  string toString() { result = super.toString() }
-
-  predicate hasLocationInfo(
-    string filepath, int startline, int startcolumn, int endline, int endcolumn
-  ) {
-    super.hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
-  }
-
   /**
    * Holds if this node is the parameter of callable `c` at the specified
    * position.
@@ -1135,17 +1146,9 @@ class ParamNode instanceof Node {
 }
 
 /** A data-flow node that represents a call argument. */
-class ArgNode instanceof Node {
+class ArgNode extends Node {
   ArgNode() { argumentNode(this, _, _) }
 
-  string toString() { result = super.toString() }
-
-  predicate hasLocationInfo(
-    string filepath, int startline, int startcolumn, int endline, int endcolumn
-  ) {
-    super.hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
-  }
-
   /** Holds if this argument occurs at the given position in the given call. */
   final predicate argumentOf(DataFlowCall call, ArgumentPosition pos) {
     argumentNode(this, call, pos)
@@ -1156,17 +1159,9 @@ class ArgNode instanceof Node {
  * A node from which flow can return to the caller. This is either a regular
  * `ReturnNode` or a `PostUpdateNode` corresponding to the value of a parameter.
  */
-class ReturnNodeExt instanceof Node {
+class ReturnNodeExt extends Node {
   ReturnNodeExt() { returnNodeExt(this, _) }
 
-  string toString() { result = super.toString() }
-
-  predicate hasLocationInfo(
-    string filepath, int startline, int startcolumn, int endline, int endcolumn
-  ) {
-    super.hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
-  }
-
   /** Gets the kind of this returned value. */
   ReturnKindExt getKind() { returnNodeExt(this, result) }
 }
@@ -1175,16 +1170,8 @@ class ReturnNodeExt instanceof Node {
  * A node to which data can flow from a call. Either an ordinary out node
  * or a post-update node associated with a call argument.
  */
-class OutNodeExt instanceof Node {
+class OutNodeExt extends Node {
   OutNodeExt() { outNodeExt(this) }
-
-  string toString() { result = super.toString() }
-
-  predicate hasLocationInfo(
-    string filepath, int startline, int startcolumn, int endline, int endcolumn
-  ) {
-    super.hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
-  }
 }
 
 /**
@@ -1400,37 +1387,67 @@ class ReturnCtx extends TReturnCtx {
   }
 }
 
+/** An approximated `Content` tagged with the type of a containing object. */
+class TypedContentApprox extends MkTypedContentApprox {
+  private ContentApprox c;
+  private DataFlowType t;
+
+  TypedContentApprox() { this = MkTypedContentApprox(c, t) }
+
+  /** Gets a typed content approximated by this value. */
+  TypedContent getATypedContent() { result = getATypedContent(this) }
+
+  /** Gets the content. */
+  ContentApprox getContent() { result = c }
+
+  /** Gets the container type. */
+  DataFlowType getContainerType() { result = t }
+
+  /** Gets a textual representation of this approximated content. */
+  string toString() { result = c.toString() }
+}
+
 /**
  * The front of an approximated access path. This is either a head or a nil.
  */
 abstract class ApproxAccessPathFront extends TApproxAccessPathFront {
   abstract string toString();
 
+  abstract DataFlowType getType();
+
   abstract boolean toBoolNonEmpty();
 
-  ContentApprox getHead() { this = TApproxFrontHead(result) }
+  TypedContentApprox getHead() { this = TApproxFrontHead(result) }
 
   pragma[nomagic]
-  Content getAHead() {
-    exists(ContentApprox cont |
+  TypedContent getAHead() {
+    exists(TypedContentApprox cont |
       this = TApproxFrontHead(cont) and
-      cont = getContentApprox(result)
+      result = cont.getATypedContent()
     )
   }
 }
 
 class ApproxAccessPathFrontNil extends ApproxAccessPathFront, TApproxFrontNil {
-  override string toString() { result = "nil" }
+  private DataFlowType t;
+
+  ApproxAccessPathFrontNil() { this = TApproxFrontNil(t) }
+
+  override string toString() { result = ppReprType(t) }
+
+  override DataFlowType getType() { result = t }
 
   override boolean toBoolNonEmpty() { result = false }
 }
 
 class ApproxAccessPathFrontHead extends ApproxAccessPathFront, TApproxFrontHead {
-  private ContentApprox c;
+  private TypedContentApprox tc;
 
-  ApproxAccessPathFrontHead() { this = TApproxFrontHead(c) }
+  ApproxAccessPathFrontHead() { this = TApproxFrontHead(tc) }
 
-  override string toString() { result = c.toString() }
+  override string toString() { result = tc.toString() }
+
+  override DataFlowType getType() { result = tc.getContainerType() }
 
   override boolean toBoolNonEmpty() { result = true }
 }
@@ -1444,31 +1461,65 @@ class ApproxAccessPathFrontOption extends TApproxAccessPathFrontOption {
   }
 }
 
+/** A `Content` tagged with the type of a containing object. */
+class TypedContent extends MkTypedContent {
+  private Content c;
+  private DataFlowType t;
+
+  TypedContent() { this = MkTypedContent(c, t) }
+
+  /** Gets the content. */
+  Content getContent() { result = c }
+
+  /** Gets the container type. */
+  DataFlowType getContainerType() { result = t }
+
+  /** Gets a textual representation of this content. */
+  string toString() { result = c.toString() }
+
+  /**
+   * Holds if access paths with this `TypedContent` at their head always should
+   * be tracked at high precision. This disables adaptive access path precision
+   * for such access paths.
+   */
+  predicate forceHighPrecision() { forceHighPrecision(c) }
+}
+
 /**
  * The front of an access path. This is either a head or a nil.
  */
 abstract class AccessPathFront extends TAccessPathFront {
   abstract string toString();
 
+  abstract DataFlowType getType();
+
   abstract ApproxAccessPathFront toApprox();
 
-  Content getHead() { this = TFrontHead(result) }
+  TypedContent getHead() { this = TFrontHead(result) }
 }
 
 class AccessPathFrontNil extends AccessPathFront, TFrontNil {
-  override string toString() { result = "nil" }
+  private DataFlowType t;
 
-  override ApproxAccessPathFront toApprox() { result = TApproxFrontNil() }
+  AccessPathFrontNil() { this = TFrontNil(t) }
+
+  override string toString() { result = ppReprType(t) }
+
+  override DataFlowType getType() { result = t }
+
+  override ApproxAccessPathFront toApprox() { result = TApproxFrontNil(t) }
 }
 
 class AccessPathFrontHead extends AccessPathFront, TFrontHead {
-  private Content c;
+  private TypedContent tc;
 
-  AccessPathFrontHead() { this = TFrontHead(c) }
+  AccessPathFrontHead() { this = TFrontHead(tc) }
 
-  override string toString() { result = c.toString() }
+  override string toString() { result = tc.toString() }
 
-  override ApproxAccessPathFront toApprox() { result.getAHead() = c }
+  override DataFlowType getType() { result = tc.getContainerType() }
+
+  override ApproxAccessPathFront toApprox() { result.getAHead() = tc }
 }
 
 /** An optional access path front. */

cpp/ql/lib/semmle/code/cpp/dataflow/internal/DataFlowImplConsistency.qll

@@ -58,9 +58,6 @@ module Consistency {
     predicate uniqueParameterNodePositionExclude(DataFlowCallable c, ParameterPosition pos, Node p) {
       none()
     }
-
-    /** Holds if `n` should be excluded from the consistency test `identityLocalStep`. */
-    predicate identityLocalStepExclude(Node n) { none() }
   }
 
   private class RelevantNode extends Node {
@@ -290,10 +287,4 @@ module Consistency {
     not exists(unique(ContentApprox approx | approx = getContentApprox(c))) and
     msg = "Non-unique content approximation."
   }
-
-  query predicate identityLocalStep(Node n, string msg) {
-    simpleLocalFlowStep(n, n) and
-    not any(ConsistencyConfiguration c).identityLocalStepExclude(n) and
-    msg = "Node steps to itself"
-  }
 }

cpp/ql/lib/semmle/code/cpp/dataflow/internal/DataFlowImplLocal.qll

@@ -313,8 +313,6 @@ private module Config implements FullStateConfigSig {
     any(Configuration config).allowImplicitRead(node, c)
   }
 
-  predicate neverSkip(Node node) { none() }
-
   int fieldFlowBranchLimit() { result = min(any(Configuration config).fieldFlowBranchLimit()) }
 
   FlowFeature getAFeature() { result = any(Configuration config).getAFeature() }

cpp/ql/lib/semmle/code/cpp/dataflow/internal/DataFlowPrivate.qll

@@ -205,8 +205,6 @@ predicate clearsContent(Node n, Content c) {
  */
 predicate expectsContent(Node n, ContentSet c) { none() }
 
-predicate typeStrongerThan(DataFlowType t1, DataFlowType t2) { none() }
-
 /** Gets the type of `n` used for type pruning. */
 Type getNodeType(Node n) {
   suppressUnusedNode(n) and
@@ -235,12 +233,6 @@ class CastNode extends Node {
   CastNode() { none() } // stub implementation
 }
 
-/**
- * Holds if `n` should never be skipped over in the `PathGraph` and in path
- * explanations.
- */
-predicate neverSkipInPathGraph(Node n) { none() }
-
 class DataFlowCallable = Function;
 
 class DataFlowExpr = Expr;

cpp/ql/lib/semmle/code/cpp/exprs/Access.qll

@@ -368,11 +368,6 @@ class FunctionAccess extends Access, @routineexpr {
   /** Gets the accessed function. */
   override Function getTarget() { funbind(underlyingElement(this), unresolveElement(result)) }
 
-  /**
-   * Gets the expression generating the function being accessed.
-   */
-  Expr getQualifier() { this.getChild(-1) = result }
-
   /** Gets a textual representation of this function access. */
   override string toString() {
     if exists(this.getTarget())

cpp/ql/lib/semmle/code/cpp/exprs/ComparisonOperation.qll

@@ -76,9 +76,9 @@ class GTExpr extends RelationalOperation, @gtexpr {
 
   override string getOperator() { result = ">" }
 
-  override Expr getGreaterOperand() { result = this.getLeftOperand() }
+  override Expr getGreaterOperand() { result = getLeftOperand() }
 
-  override Expr getLesserOperand() { result = this.getRightOperand() }
+  override Expr getLesserOperand() { result = getRightOperand() }
 }
 
 /**
@@ -92,9 +92,9 @@ class LTExpr extends RelationalOperation, @ltexpr {
 
   override string getOperator() { result = "<" }
 
-  override Expr getGreaterOperand() { result = this.getRightOperand() }
+  override Expr getGreaterOperand() { result = getRightOperand() }
 
-  override Expr getLesserOperand() { result = this.getLeftOperand() }
+  override Expr getLesserOperand() { result = getLeftOperand() }
 }
 
 /**
@@ -108,9 +108,9 @@ class GEExpr extends RelationalOperation, @geexpr {
 
   override string getOperator() { result = ">=" }
 
-  override Expr getGreaterOperand() { result = this.getLeftOperand() }
+  override Expr getGreaterOperand() { result = getLeftOperand() }
 
-  override Expr getLesserOperand() { result = this.getRightOperand() }
+  override Expr getLesserOperand() { result = getRightOperand() }
 }
 
 /**
@@ -124,7 +124,7 @@ class LEExpr extends RelationalOperation, @leexpr {
 
   override string getOperator() { result = "<=" }
 
-  override Expr getGreaterOperand() { result = this.getRightOperand() }
+  override Expr getGreaterOperand() { result = getRightOperand() }
 
-  override Expr getLesserOperand() { result = this.getLeftOperand() }
+  override Expr getLesserOperand() { result = getLeftOperand() }
 }

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlow.qll

@@ -46,14 +46,6 @@ signature module ConfigSig {
    */
   default predicate allowImplicitRead(Node node, ContentSet c) { none() }
 
-  /**
-   * Holds if `node` should never be skipped over in the `PathGraph` and in path
-   * explanations.
-   */
-  default predicate neverSkip(Node node) {
-    isAdditionalFlowStep(node, _) or isAdditionalFlowStep(_, node)
-  }
-
   /**
    * Gets the virtual dispatch branching limit when calculating field flow.
    * This can be overridden to a smaller value to improve performance (a
@@ -122,7 +114,7 @@ signature module StateConfigSig {
    * Holds if data flow through `node` is prohibited when the flow state is
    * `state`.
    */
-  default predicate isBarrier(Node node, FlowState state) { none() }
+  predicate isBarrier(Node node, FlowState state);
 
   /** Holds if data flow into `node` is prohibited. */
   default predicate isBarrierIn(Node node) { none() }
@@ -139,9 +131,7 @@ signature module StateConfigSig {
    * Holds if data may flow from `node1` to `node2` in addition to the normal data-flow steps.
    * This step is only applicable in `state1` and updates the flow state to `state2`.
    */
-  default predicate isAdditionalFlowStep(Node node1, FlowState state1, Node node2, FlowState state2) {
-    none()
-  }
+  predicate isAdditionalFlowStep(Node node1, FlowState state1, Node node2, FlowState state2);
 
   /**
    * Holds if an arbitrary number of implicit read steps of content `c` may be
@@ -149,17 +139,6 @@ signature module StateConfigSig {
    */
   default predicate allowImplicitRead(Node node, ContentSet c) { none() }
 
-  /**
-   * Holds if `node` should never be skipped over in the `PathGraph` and in path
-   * explanations.
-   */
-  default predicate neverSkip(Node node) {
-    isAdditionalFlowStep(node, _) or
-    isAdditionalFlowStep(_, node) or
-    isAdditionalFlowStep(node, _, _, _) or
-    isAdditionalFlowStep(_, _, node, _)
-  }
-
   /**
    * Gets the virtual dispatch branching limit when calculating field flow.
    * This can be overridden to a smaller value to improve performance (a
@@ -382,52 +361,3 @@ module MergePathGraph<
     }
   }
 }
-
-/**
- * Constructs a `PathGraph` from three `PathGraph`s by disjoint union.
- */
-module MergePathGraph3<
-  PathNodeSig PathNode1, PathNodeSig PathNode2, PathNodeSig PathNode3,
-  PathGraphSig<PathNode1> Graph1, PathGraphSig<PathNode2> Graph2, PathGraphSig<PathNode3> Graph3>
-{
-  private module MergedInner = MergePathGraph<PathNode1, PathNode2, Graph1, Graph2>;
-
-  private module Merged =
-    MergePathGraph<MergedInner::PathNode, PathNode3, MergedInner::PathGraph, Graph3>;
-
-  /** A node in a graph of path explanations that is formed by disjoint union of the three given graphs. */
-  class PathNode instanceof Merged::PathNode {
-    /** Gets this as a projection on the first given `PathGraph`. */
-    PathNode1 asPathNode1() { result = super.asPathNode1().asPathNode1() }
-
-    /** Gets this as a projection on the second given `PathGraph`. */
-    PathNode2 asPathNode2() { result = super.asPathNode1().asPathNode2() }
-
-    /** Gets this as a projection on the third given `PathGraph`. */
-    PathNode3 asPathNode3() { result = super.asPathNode2() }
-
-    /** Gets a textual representation of this element. */
-    string toString() { result = super.toString() }
-
-    /**
-     * Holds if this element is at the specified location.
-     * The location spans column `startcolumn` of line `startline` to
-     * column `endcolumn` of line `endline` in file `filepath`.
-     * For more information, see
-     * [Locations](https://codeql.github.com/docs/writing-codeql-queries/providing-locations-in-codeql-queries/).
-     */
-    predicate hasLocationInfo(
-      string filepath, int startline, int startcolumn, int endline, int endcolumn
-    ) {
-      super.hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
-    }
-
-    /** Gets the underlying `Node`. */
-    Node getNode() { result = super.getNode() }
-  }
-
-  /**
-   * Provides the query predicates needed to include a graph in a path-problem query.
-   */
-  module PathGraph = Merged::PathGraph;
-}

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowImpl1.qll

@@ -313,8 +313,6 @@ private module Config implements FullStateConfigSig {
     any(Configuration config).allowImplicitRead(node, c)
   }
 
-  predicate neverSkip(Node node) { none() }
-
   int fieldFlowBranchLimit() { result = min(any(Configuration config).fieldFlowBranchLimit()) }
 
   FlowFeature getAFeature() { result = any(Configuration config).getAFeature() }

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowImpl2.qll

@@ -313,8 +313,6 @@ private module Config implements FullStateConfigSig {
     any(Configuration config).allowImplicitRead(node, c)
   }
 
-  predicate neverSkip(Node node) { none() }
-
   int fieldFlowBranchLimit() { result = min(any(Configuration config).fieldFlowBranchLimit()) }
 
   FlowFeature getAFeature() { result = any(Configuration config).getAFeature() }

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowImpl3.qll

@@ -313,8 +313,6 @@ private module Config implements FullStateConfigSig {
     any(Configuration config).allowImplicitRead(node, c)
   }
 
-  predicate neverSkip(Node node) { none() }
-
   int fieldFlowBranchLimit() { result = min(any(Configuration config).fieldFlowBranchLimit()) }
 
   FlowFeature getAFeature() { result = any(Configuration config).getAFeature() }

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowImpl4.qll

@@ -313,8 +313,6 @@ private module Config implements FullStateConfigSig {
     any(Configuration config).allowImplicitRead(node, c)
   }
 
-  predicate neverSkip(Node node) { none() }
-
   int fieldFlowBranchLimit() { result = min(any(Configuration config).fieldFlowBranchLimit()) }
 
   FlowFeature getAFeature() { result = any(Configuration config).getAFeature() }

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowImplCommon.qll

@@ -187,6 +187,7 @@ private module LambdaFlow {
     else any()
   }
 
+  pragma[assume_small_delta]
   pragma[nomagic]
   predicate revLambdaFlow0(
     DataFlowCall lambdaCall, LambdaCallKind kind, Node node, DataFlowType t, boolean toReturn,
@@ -273,6 +274,7 @@ private module LambdaFlow {
     )
   }
 
+  pragma[assume_small_delta]
   pragma[nomagic]
   predicate revLambdaFlowOut(
     DataFlowCall lambdaCall, LambdaCallKind kind, TReturnPositionSimple pos, DataFlowType t,
@@ -813,15 +815,7 @@ private module Cached {
     )
   }
 
-  /**
-   * Holds if data can flow from `node1` to `node2` via a direct assignment to
-   * `c`.
-   *
-   * This includes reverse steps through reads when the result of the read has
-   * been stored into, in order to handle cases like `x.f1.f2 = y`.
-   */
-  cached
-  predicate store(
+  private predicate store(
     Node node1, Content c, Node node2, DataFlowType contentType, DataFlowType containerType
   ) {
     exists(ContentSet cs |
@@ -829,6 +823,18 @@ private module Cached {
     )
   }
 
+  /**
+   * Holds if data can flow from `node1` to `node2` via a direct assignment to
+   * `f`.
+   *
+   * This includes reverse steps through reads when the result of the read has
+   * been stored into, in order to handle cases like `x.f1.f2 = y`.
+   */
+  cached
+  predicate store(Node node1, TypedContent tc, Node node2, DataFlowType contentType) {
+    store(node1, tc.getContent(), node2, contentType, tc.getContainerType())
+  }
+
   /**
    * Holds if data can flow from `fromNode` to `toNode` because they are the post-update
    * nodes of some function output and input respectively, where the output and input
@@ -926,15 +932,36 @@ private module Cached {
     TReturnCtxNoFlowThrough() or
     TReturnCtxMaybeFlowThrough(ReturnPosition pos)
 
+  cached
+  newtype TTypedContentApprox =
+    MkTypedContentApprox(ContentApprox c, DataFlowType t) {
+      exists(Content cont |
+        c = getContentApprox(cont) and
+        store(_, cont, _, _, t)
+      )
+    }
+
+  cached
+  newtype TTypedContent = MkTypedContent(Content c, DataFlowType t) { store(_, c, _, _, t) }
+
+  cached
+  TypedContent getATypedContent(TypedContentApprox c) {
+    exists(ContentApprox cls, DataFlowType t, Content cont |
+      c = MkTypedContentApprox(cls, pragma[only_bind_into](t)) and
+      result = MkTypedContent(cont, pragma[only_bind_into](t)) and
+      cls = getContentApprox(cont)
+    )
+  }
+
   cached
   newtype TAccessPathFront =
-    TFrontNil() or
-    TFrontHead(Content c)
+    TFrontNil(DataFlowType t) or
+    TFrontHead(TypedContent tc)
 
   cached
   newtype TApproxAccessPathFront =
-    TApproxFrontNil() or
-    TApproxFrontHead(ContentApprox c)
+    TApproxFrontNil(DataFlowType t) or
+    TApproxFrontHead(TypedContentApprox tc)
 
   cached
   newtype TAccessPathFrontOption =
@@ -959,16 +986,8 @@ predicate recordDataFlowCallSite(DataFlowCall call, DataFlowCallable callable) {
 /**
  * A `Node` at which a cast can occur such that the type should be checked.
  */
-class CastingNode instanceof Node {
+class CastingNode extends Node {
   CastingNode() { castingNode(this) }
-
-  string toString() { result = super.toString() }
-
-  predicate hasLocationInfo(
-    string filepath, int startline, int startcolumn, int endline, int endcolumn
-  ) {
-    super.hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
-  }
 }
 
 private predicate readStepWithTypes(
@@ -1116,17 +1135,9 @@ LocalCallContext getLocalCallContext(CallContext ctx, DataFlowCallable callable)
  * The value of a parameter at function entry, viewed as a node in a data
  * flow graph.
  */
-class ParamNode instanceof Node {
+class ParamNode extends Node {
   ParamNode() { parameterNode(this, _, _) }
 
-  string toString() { result = super.toString() }
-
-  predicate hasLocationInfo(
-    string filepath, int startline, int startcolumn, int endline, int endcolumn
-  ) {
-    super.hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
-  }
-
   /**
    * Holds if this node is the parameter of callable `c` at the specified
    * position.
@@ -1135,17 +1146,9 @@ class ParamNode instanceof Node {
 }
 
 /** A data-flow node that represents a call argument. */
-class ArgNode instanceof Node {
+class ArgNode extends Node {
   ArgNode() { argumentNode(this, _, _) }
 
-  string toString() { result = super.toString() }
-
-  predicate hasLocationInfo(
-    string filepath, int startline, int startcolumn, int endline, int endcolumn
-  ) {
-    super.hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
-  }
-
   /** Holds if this argument occurs at the given position in the given call. */
   final predicate argumentOf(DataFlowCall call, ArgumentPosition pos) {
     argumentNode(this, call, pos)
@@ -1156,17 +1159,9 @@ class ArgNode instanceof Node {
  * A node from which flow can return to the caller. This is either a regular
  * `ReturnNode` or a `PostUpdateNode` corresponding to the value of a parameter.
  */
-class ReturnNodeExt instanceof Node {
+class ReturnNodeExt extends Node {
   ReturnNodeExt() { returnNodeExt(this, _) }
 
-  string toString() { result = super.toString() }
-
-  predicate hasLocationInfo(
-    string filepath, int startline, int startcolumn, int endline, int endcolumn
-  ) {
-    super.hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
-  }
-
   /** Gets the kind of this returned value. */
   ReturnKindExt getKind() { returnNodeExt(this, result) }
 }
@@ -1175,16 +1170,8 @@ class ReturnNodeExt instanceof Node {
  * A node to which data can flow from a call. Either an ordinary out node
  * or a post-update node associated with a call argument.
  */
-class OutNodeExt instanceof Node {
+class OutNodeExt extends Node {
   OutNodeExt() { outNodeExt(this) }
-
-  string toString() { result = super.toString() }
-
-  predicate hasLocationInfo(
-    string filepath, int startline, int startcolumn, int endline, int endcolumn
-  ) {
-    super.hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
-  }
 }
 
 /**
@@ -1400,37 +1387,67 @@ class ReturnCtx extends TReturnCtx {
   }
 }
 
+/** An approximated `Content` tagged with the type of a containing object. */
+class TypedContentApprox extends MkTypedContentApprox {
+  private ContentApprox c;
+  private DataFlowType t;
+
+  TypedContentApprox() { this = MkTypedContentApprox(c, t) }
+
+  /** Gets a typed content approximated by this value. */
+  TypedContent getATypedContent() { result = getATypedContent(this) }
+
+  /** Gets the content. */
+  ContentApprox getContent() { result = c }
+
+  /** Gets the container type. */
+  DataFlowType getContainerType() { result = t }
+
+  /** Gets a textual representation of this approximated content. */
+  string toString() { result = c.toString() }
+}
+
 /**
  * The front of an approximated access path. This is either a head or a nil.
  */
 abstract class ApproxAccessPathFront extends TApproxAccessPathFront {
   abstract string toString();
 
+  abstract DataFlowType getType();
+
   abstract boolean toBoolNonEmpty();
 
-  ContentApprox getHead() { this = TApproxFrontHead(result) }
+  TypedContentApprox getHead() { this = TApproxFrontHead(result) }
 
   pragma[nomagic]
-  Content getAHead() {
-    exists(ContentApprox cont |
+  TypedContent getAHead() {
+    exists(TypedContentApprox cont |
       this = TApproxFrontHead(cont) and
-      cont = getContentApprox(result)
+      result = cont.getATypedContent()
     )
   }
 }
 
 class ApproxAccessPathFrontNil extends ApproxAccessPathFront, TApproxFrontNil {
-  override string toString() { result = "nil" }
+  private DataFlowType t;
+
+  ApproxAccessPathFrontNil() { this = TApproxFrontNil(t) }
+
+  override string toString() { result = ppReprType(t) }
+
+  override DataFlowType getType() { result = t }
 
   override boolean toBoolNonEmpty() { result = false }
 }
 
 class ApproxAccessPathFrontHead extends ApproxAccessPathFront, TApproxFrontHead {
-  private ContentApprox c;
+  private TypedContentApprox tc;
 
-  ApproxAccessPathFrontHead() { this = TApproxFrontHead(c) }
+  ApproxAccessPathFrontHead() { this = TApproxFrontHead(tc) }
 
-  override string toString() { result = c.toString() }
+  override string toString() { result = tc.toString() }
+
+  override DataFlowType getType() { result = tc.getContainerType() }
 
   override boolean toBoolNonEmpty() { result = true }
 }
@@ -1444,31 +1461,65 @@ class ApproxAccessPathFrontOption extends TApproxAccessPathFrontOption {
   }
 }
 
+/** A `Content` tagged with the type of a containing object. */
+class TypedContent extends MkTypedContent {
+  private Content c;
+  private DataFlowType t;
+
+  TypedContent() { this = MkTypedContent(c, t) }
+
+  /** Gets the content. */
+  Content getContent() { result = c }
+
+  /** Gets the container type. */
+  DataFlowType getContainerType() { result = t }
+
+  /** Gets a textual representation of this content. */
+  string toString() { result = c.toString() }
+
+  /**
+   * Holds if access paths with this `TypedContent` at their head always should
+   * be tracked at high precision. This disables adaptive access path precision
+   * for such access paths.
+   */
+  predicate forceHighPrecision() { forceHighPrecision(c) }
+}
+
 /**
  * The front of an access path. This is either a head or a nil.
  */
 abstract class AccessPathFront extends TAccessPathFront {
   abstract string toString();
 
+  abstract DataFlowType getType();
+
   abstract ApproxAccessPathFront toApprox();
 
-  Content getHead() { this = TFrontHead(result) }
+  TypedContent getHead() { this = TFrontHead(result) }
 }
 
 class AccessPathFrontNil extends AccessPathFront, TFrontNil {
-  override string toString() { result = "nil" }
+  private DataFlowType t;
 
-  override ApproxAccessPathFront toApprox() { result = TApproxFrontNil() }
+  AccessPathFrontNil() { this = TFrontNil(t) }
+
+  override string toString() { result = ppReprType(t) }
+
+  override DataFlowType getType() { result = t }
+
+  override ApproxAccessPathFront toApprox() { result = TApproxFrontNil(t) }
 }
 
 class AccessPathFrontHead extends AccessPathFront, TFrontHead {
-  private Content c;
+  private TypedContent tc;
 
-  AccessPathFrontHead() { this = TFrontHead(c) }
+  AccessPathFrontHead() { this = TFrontHead(tc) }
 
-  override string toString() { result = c.toString() }
+  override string toString() { result = tc.toString() }
 
-  override ApproxAccessPathFront toApprox() { result.getAHead() = c }
+  override DataFlowType getType() { result = tc.getContainerType() }
+
+  override ApproxAccessPathFront toApprox() { result.getAHead() = tc }
 }
 
 /** An optional access path front. */

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowImplConsistency.qll

@@ -58,9 +58,6 @@ module Consistency {
     predicate uniqueParameterNodePositionExclude(DataFlowCallable c, ParameterPosition pos, Node p) {
       none()
     }
-
-    /** Holds if `n` should be excluded from the consistency test `identityLocalStep`. */
-    predicate identityLocalStepExclude(Node n) { none() }
   }
 
   private class RelevantNode extends Node {
@@ -290,10 +287,4 @@ module Consistency {
     not exists(unique(ContentApprox approx | approx = getContentApprox(c))) and
     msg = "Non-unique content approximation."
   }
-
-  query predicate identityLocalStep(Node n, string msg) {
-    simpleLocalFlowStep(n, n) and
-    not any(ConsistencyConfiguration c).identityLocalStepExclude(n) and
-    msg = "Node steps to itself"
-  }
 }

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowPrivate.qll

@@ -193,89 +193,86 @@ private class SingleUseOperandNode0 extends OperandNode0, TSingleUseOperandNode0
   SingleUseOperandNode0() { this = TSingleUseOperandNode0(op) }
 }
 
-private module IndirectOperands {
+/**
+ * INTERNAL: Do not use.
+ *
+ * A node that represents the indirect value of an operand in the IR
+ * after `index` number of loads.
+ *
+ * Note: Unlike `RawIndirectOperand`, a value of type `IndirectOperand` may
+ * be an `OperandNode`.
+ */
+class IndirectOperand extends Node {
+  Operand operand;
+  int indirectionIndex;
+
+  IndirectOperand() {
+    this.(RawIndirectOperand).getOperand() = operand and
+    this.(RawIndirectOperand).getIndirectionIndex() = indirectionIndex
+    or
+    this.(OperandNode).getOperand() =
+      Ssa::getIRRepresentationOfIndirectOperand(operand, indirectionIndex)
+  }
+
+  /** Gets the underlying operand. */
+  Operand getOperand() { result = operand }
+
+  /** Gets the underlying indirection index. */
+  int getIndirectionIndex() { result = indirectionIndex }
+
   /**
-   * INTERNAL: Do not use.
-   *
-   * A node that represents the indirect value of an operand in the IR
-   * after `index` number of loads.
-   *
-   * Note: Unlike `RawIndirectOperand`, a value of type `IndirectOperand` may
-   * be an `OperandNode`.
+   * Holds if this `IndirectOperand` is represented directly in the IR instead of
+   * a `RawIndirectionOperand` with operand `op` and indirection index `index`.
    */
-  abstract class IndirectOperand extends Node {
-    /** Gets the underlying operand and the underlying indirection index. */
-    abstract predicate hasOperandAndIndirectionIndex(Operand operand, int indirectionIndex);
-  }
-
-  private class IndirectOperandFromRaw extends IndirectOperand instanceof RawIndirectOperand {
-    override predicate hasOperandAndIndirectionIndex(Operand operand, int indirectionIndex) {
-      operand = RawIndirectOperand.super.getOperand() and
-      indirectionIndex = RawIndirectOperand.super.getIndirectionIndex()
-    }
-  }
-
-  private class IndirectOperandFromIRRepr extends IndirectOperand {
-    Operand operand;
-    int indirectionIndex;
-
-    IndirectOperandFromIRRepr() {
-      exists(Operand repr |
-        repr = Ssa::getIRRepresentationOfIndirectOperand(operand, indirectionIndex) and
-        nodeHasOperand(this, repr, indirectionIndex - 1)
-      )
-    }
-
-    override predicate hasOperandAndIndirectionIndex(Operand op, int index) {
-      op = operand and index = indirectionIndex
-    }
+  predicate isIRRepresentationOf(Operand op, int index) {
+    this instanceof OperandNode and
+    (
+      op = operand and
+      index = indirectionIndex
+    )
   }
 }
 
-import IndirectOperands
+/**
+ * INTERNAL: Do not use.
+ *
+ * A node that represents the indirect value of an instruction in the IR
+ * after `index` number of loads.
+ *
+ * Note: Unlike `RawIndirectInstruction`, a value of type `IndirectInstruction` may
+ * be an `InstructionNode`.
+ */
+class IndirectInstruction extends Node {
+  Instruction instr;
+  int indirectionIndex;
+
+  IndirectInstruction() {
+    this.(RawIndirectInstruction).getInstruction() = instr and
+    this.(RawIndirectInstruction).getIndirectionIndex() = indirectionIndex
+    or
+    this.(InstructionNode).getInstruction() =
+      Ssa::getIRRepresentationOfIndirectInstruction(instr, indirectionIndex)
+  }
+
+  /** Gets the underlying instruction. */
+  Instruction getInstruction() { result = instr }
+
+  /** Gets the underlying indirection index. */
+  int getIndirectionIndex() { result = indirectionIndex }
 
-private module IndirectInstructions {
   /**
-   * INTERNAL: Do not use.
-   *
-   * A node that represents the indirect value of an instruction in the IR
-   * after `index` number of loads.
-   *
-   * Note: Unlike `RawIndirectInstruction`, a value of type `IndirectInstruction` may
-   * be an `InstructionNode`.
+   * Holds if this `IndirectInstruction` is represented directly in the IR instead of
+   * a `RawIndirectionInstruction` with instruction `i` and indirection index `index`.
    */
-  abstract class IndirectInstruction extends Node {
-    /** Gets the underlying operand and the underlying indirection index. */
-    abstract predicate hasInstructionAndIndirectionIndex(Instruction instr, int index);
-  }
-
-  private class IndirectInstructionFromRaw extends IndirectInstruction instanceof RawIndirectInstruction
-  {
-    override predicate hasInstructionAndIndirectionIndex(Instruction instr, int index) {
-      instr = RawIndirectInstruction.super.getInstruction() and
-      index = RawIndirectInstruction.super.getIndirectionIndex()
-    }
-  }
-
-  private class IndirectInstructionFromIRRepr extends IndirectInstruction {
-    Instruction instr;
-    int indirectionIndex;
-
-    IndirectInstructionFromIRRepr() {
-      exists(Instruction repr |
-        repr = Ssa::getIRRepresentationOfIndirectInstruction(instr, indirectionIndex) and
-        nodeHasInstruction(this, repr, indirectionIndex - 1)
-      )
-    }
-
-    override predicate hasInstructionAndIndirectionIndex(Instruction i, int index) {
-      i = instr and index = indirectionIndex
-    }
+  predicate isIRRepresentationOf(Instruction i, int index) {
+    this instanceof InstructionNode and
+    (
+      i = instr and
+      index = indirectionIndex
+    )
   }
 }
 
-import IndirectInstructions
-
 /** Gets the callable in which this node occurs. */
 DataFlowCallable nodeGetEnclosingCallable(Node n) { result = n.getEnclosingCallable() }
 
@@ -321,11 +318,9 @@ private class PrimaryArgumentNode extends ArgumentNode, OperandNode {
 
 private class SideEffectArgumentNode extends ArgumentNode, SideEffectOperandNode {
   override predicate argumentOf(DataFlowCall dfCall, ArgumentPosition pos) {
-    exists(int indirectionIndex |
-      pos = TIndirectionPosition(argumentIndex, pragma[only_bind_into](indirectionIndex)) and
-      this.getCallInstruction() = dfCall and
-      super.hasAddressOperandAndIndirectionIndex(_, pragma[only_bind_into](indirectionIndex))
-    )
+    this.getCallInstruction() = dfCall and
+    pos.(IndirectionPosition).getArgumentIndex() = this.getArgumentIndex() and
+    pos.(IndirectionPosition).getIndirectionIndex() = super.getIndirectionIndex()
   }
 }
 
@@ -612,21 +607,13 @@ OutNode getAnOutNode(DataFlowCall call, ReturnKind kind) {
   result.getReturnKind() = kind
 }
 
-/** A variable that behaves like a global variable. */
-class GlobalLikeVariable extends Variable {
-  GlobalLikeVariable() {
-    this instanceof Cpp::GlobalOrNamespaceVariable or
-    this instanceof Cpp::StaticLocalVariable
-  }
-}
-
 /**
  * Holds if data can flow from `node1` to `node2` in a way that loses the
  * calling context. For example, this would happen with flow through a
  * global or static variable.
  */
 predicate jumpStep(Node n1, Node n2) {
-  exists(GlobalLikeVariable v |
+  exists(Cpp::GlobalOrNamespaceVariable v |
     exists(Ssa::GlobalUse globalUse |
       v = globalUse.getVariable() and
       n1.(FinalGlobalValue).getGlobalUse() = globalUse
@@ -653,16 +640,13 @@ predicate jumpStep(Node n1, Node n2) {
  * Holds if data can flow from `node1` to `node2` via an assignment to `f`.
  * Thus, `node2` references an object with a field `f` that contains the
  * value of `node1`.
- *
- * The boolean `certain` is true if the destination address does not involve
- * any pointer arithmetic, and false otherwise.
  */
-predicate storeStepImpl(Node node1, Content c, PostFieldUpdateNode node2, boolean certain) {
+predicate storeStep(Node node1, Content c, PostFieldUpdateNode node2) {
   exists(int indirectionIndex1, int numberOfLoads, StoreInstruction store |
     nodeHasInstruction(node1, store, pragma[only_bind_into](indirectionIndex1)) and
     node2.getIndirectionIndex() = 1 and
     numberOfLoadsFromOperand(node2.getFieldAddress(), store.getDestinationAddressOperand(),
-      numberOfLoads, certain)
+      numberOfLoads)
   |
     exists(FieldContent fc | fc = c |
       fc.getField() = node2.getUpdatedField() and
@@ -676,34 +660,21 @@ predicate storeStepImpl(Node node1, Content c, PostFieldUpdateNode node2, boolea
   )
 }
 
-/**
- * Holds if data can flow from `node1` to `node2` via an assignment to `f`.
- * Thus, `node2` references an object with a field `f` that contains the
- * value of `node1`.
- */
-predicate storeStep(Node node1, Content c, PostFieldUpdateNode node2) {
-  storeStepImpl(node1, c, node2, _)
-}
-
 /**
  * Holds if `operandFrom` flows to `operandTo` using a sequence of conversion-like
  * operations and exactly `n` `LoadInstruction` operations.
  */
-private predicate numberOfLoadsFromOperandRec(
-  Operand operandFrom, Operand operandTo, int ind, boolean certain
-) {
+private predicate numberOfLoadsFromOperandRec(Operand operandFrom, Operand operandTo, int ind) {
   exists(Instruction load | Ssa::isDereference(load, operandFrom) |
-    operandTo = operandFrom and ind = 0 and certain = true
+    operandTo = operandFrom and ind = 0
     or
-    numberOfLoadsFromOperand(load.getAUse(), operandTo, ind - 1, certain)
+    numberOfLoadsFromOperand(load.getAUse(), operandTo, ind - 1)
   )
   or
-  exists(Operand op, Instruction instr, boolean isPointerArith, boolean certain0 |
+  exists(Operand op, Instruction instr |
     instr = op.getDef() and
-    conversionFlow(operandFrom, instr, isPointerArith, _) and
-    numberOfLoadsFromOperand(op, operandTo, ind, certain0)
-  |
-    if isPointerArith = true then certain = false else certain = certain0
+    conversionFlow(operandFrom, instr, _, _) and
+    numberOfLoadsFromOperand(op, operandTo, ind)
   )
 }
 
@@ -711,16 +682,13 @@ private predicate numberOfLoadsFromOperandRec(
  * Holds if `operandFrom` flows to `operandTo` using a sequence of conversion-like
  * operations and exactly `n` `LoadInstruction` operations.
  */
-private predicate numberOfLoadsFromOperand(
-  Operand operandFrom, Operand operandTo, int n, boolean certain
-) {
-  numberOfLoadsFromOperandRec(operandFrom, operandTo, n, certain)
+private predicate numberOfLoadsFromOperand(Operand operandFrom, Operand operandTo, int n) {
+  numberOfLoadsFromOperandRec(operandFrom, operandTo, n)
   or
   not Ssa::isDereference(_, operandFrom) and
   not conversionFlow(operandFrom, _, _, _) and
   operandFrom = operandTo and
-  n = 0 and
-  certain = true
+  n = 0
 }
 
 // Needed to join on both an operand and an index at the same time.
@@ -750,7 +718,7 @@ predicate readStep(Node node1, Content c, Node node2) {
     // The `1` here matches the `node2.getIndirectionIndex() = 1` conjunct
     // in `storeStep`.
     nodeHasOperand(node1, fa1.getObjectAddressOperand(), 1) and
-    numberOfLoadsFromOperand(fa1, operand, numberOfLoads, _)
+    numberOfLoadsFromOperand(fa1, operand, numberOfLoads)
   |
     exists(FieldContent fc | fc = c |
       fc.getField() = fa1.getField() and
@@ -768,33 +736,7 @@ predicate readStep(Node node1, Content c, Node node2) {
  * Holds if values stored inside content `c` are cleared at node `n`.
  */
 predicate clearsContent(Node n, Content c) {
-  n =
-    any(PostUpdateNode pun, Content d | d.impliesClearOf(c) and storeStepImpl(_, d, pun, true) | pun)
-        .getPreUpdateNode() and
-  (
-    // The crement operations and pointer addition and subtraction self-assign. We do not
-    // want to clear the contents if it is indirectly pointed at by any of these operations,
-    // as part of the contents might still be accessible afterwards. If there is no such
-    // indirection clearing the contents is safe.
-    not exists(Operand op, Cpp::Operation p |
-      n.(IndirectOperand).hasOperandAndIndirectionIndex(op, _) and
-      (
-        p instanceof Cpp::AssignPointerAddExpr or
-        p instanceof Cpp::AssignPointerSubExpr or
-        p instanceof Cpp::CrementOperation
-      )
-    |
-      p.getAnOperand() = op.getUse().getAst()
-    )
-    or
-    forex(PostUpdateNode pun, Content d |
-      pragma[only_bind_into](d).impliesClearOf(pragma[only_bind_into](c)) and
-      storeStepImpl(_, d, pun, true) and
-      pun.getPreUpdateNode() = n
-    |
-      c.getIndirectionIndex() = d.getIndirectionIndex()
-    )
-  )
+  none() // stub implementation
 }
 
 /**
@@ -803,8 +745,6 @@ predicate clearsContent(Node n, Content c) {
  */
 predicate expectsContent(Node n, ContentSet c) { none() }
 
-predicate typeStrongerThan(DataFlowType t1, DataFlowType t2) { none() }
-
 /** Gets the type of `n` used for type pruning. */
 DataFlowType getNodeType(Node n) {
   suppressUnusedNode(n) and
@@ -833,12 +773,6 @@ class CastNode extends Node {
   CastNode() { none() } // stub implementation
 }
 
-/**
- * Holds if `n` should never be skipped over in the `PathGraph` and in path
- * explanations.
- */
-predicate neverSkipInPathGraph(Node n) { none() }
-
 /**
  * A function that may contain code or a variable that may contain itself. When
  * flow crosses from one _enclosing callable_ to another, the interprocedural
@@ -856,73 +790,7 @@ class DataFlowCall extends CallInstruction {
   Function getEnclosingCallable() { result = this.getEnclosingFunction() }
 }
 
-module IsUnreachableInCall {
-  private import semmle.code.cpp.ir.ValueNumbering
-  private import semmle.code.cpp.controlflow.IRGuards as G
-
-  private class ConstantIntegralTypeArgumentNode extends PrimaryArgumentNode {
-    int value;
-
-    ConstantIntegralTypeArgumentNode() {
-      value = op.getDef().(IntegerConstantInstruction).getValue().toInt()
-    }
-
-    int getValue() { result = value }
-  }
-
-  pragma[nomagic]
-  private predicate ensuresEq(Operand left, Operand right, int k, IRBlock block, boolean areEqual) {
-    any(G::IRGuardCondition guard).ensuresEq(left, right, k, block, areEqual)
-  }
-
-  pragma[nomagic]
-  private predicate ensuresLt(Operand left, Operand right, int k, IRBlock block, boolean areEqual) {
-    any(G::IRGuardCondition guard).ensuresLt(left, right, k, block, areEqual)
-  }
-
-  predicate isUnreachableInCall(Node n, DataFlowCall call) {
-    exists(
-      DirectParameterNode paramNode, ConstantIntegralTypeArgumentNode arg,
-      IntegerConstantInstruction constant, int k, Operand left, Operand right, IRBlock block
-    |
-      // arg flows into `paramNode`
-      DataFlowImplCommon::viableParamArg(call, paramNode, arg) and
-      left = constant.getAUse() and
-      right = valueNumber(paramNode.getInstruction()).getAUse() and
-      block = n.getBasicBlock()
-    |
-      // and there's a guard condition which ensures that the result of `left == right + k` is `areEqual`
-      exists(boolean areEqual |
-        ensuresEq(pragma[only_bind_into](left), pragma[only_bind_into](right),
-          pragma[only_bind_into](k), pragma[only_bind_into](block), areEqual)
-      |
-        // this block ensures that left = right + k, but it holds that `left != right + k`
-        areEqual = true and
-        constant.getValue().toInt() != arg.getValue() + k
-        or
-        // this block ensures that or `left != right + k`, but it holds that `left = right + k`
-        areEqual = false and
-        constant.getValue().toInt() = arg.getValue() + k
-      )
-      or
-      // or there's a guard condition which ensures that the result of `left < right + k` is `isLessThan`
-      exists(boolean isLessThan |
-        ensuresLt(pragma[only_bind_into](left), pragma[only_bind_into](right),
-          pragma[only_bind_into](k), pragma[only_bind_into](block), isLessThan)
-      |
-        isLessThan = true and
-        // this block ensures that `left < right + k`, but it holds that `left >= right + k`
-        constant.getValue().toInt() >= arg.getValue() + k
-        or
-        // this block ensures that `left >= right + k`, but it holds that `left < right + k`
-        isLessThan = false and
-        constant.getValue().toInt() < arg.getValue() + k
-      )
-    )
-  }
-}
-
-import IsUnreachableInCall
+predicate isUnreachableInCall(Node n, DataFlowCall call) { none() } // stub implementation
 
 int accessPathLimit() { result = 5 }
 
@@ -961,7 +829,7 @@ predicate additionalLambdaFlowStep(Node nodeFrom, Node nodeTo, boolean preserves
  * One example would be to allow flow like `p.foo = p.bar;`, which is disallowed
  * by default as a heuristic.
  */
-predicate allowParameterReturnInSelf(ParameterNode p) { p instanceof IndirectParameterNode }
+predicate allowParameterReturnInSelf(ParameterNode p) { none() }
 
 private predicate fieldHasApproxName(Field f, string s) {
   s = f.getName().charAt(0) and

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowUtil.qll

@@ -274,7 +274,7 @@ class Node extends TIRDataFlowNode {
    * represents the value of `**x` going into `f`.
    */
   Expr asIndirectArgument(int index) {
-    this.(SideEffectOperandNode).hasAddressOperandAndIndirectionIndex(_, index) and
+    this.(SideEffectOperandNode).getIndirectionIndex() = index and
     result = this.(SideEffectOperandNode).getArgument()
   }
 
@@ -317,7 +317,7 @@ class Node extends TIRDataFlowNode {
     index = 0 and
     result = this.(ExplicitParameterNode).getParameter()
     or
-    this.(IndirectParameterNode).hasInstructionAndIndirectionIndex(_, index) and
+    this.(IndirectParameterNode).getIndirectionIndex() = index and
     result = this.(IndirectParameterNode).getParameter()
   }
 
@@ -562,14 +562,6 @@ class SsaPhiNode extends Node, TSsaPhiNode {
 
   /** Gets the source variable underlying this phi node. */
   Ssa::SourceVariable getSourceVariable() { result = phi.getSourceVariable() }
-
-  /**
-   * Holds if this phi node is a phi-read node.
-   *
-   * Phi-read nodes are like normal phi nodes, but they are inserted based
-   * on reads instead of writes.
-   */
-  predicate isPhiRead() { phi.isPhiRead() }
 }
 
 /**
@@ -577,20 +569,15 @@ class SsaPhiNode extends Node, TSsaPhiNode {
  *
  * A node representing a value after leaving a function.
  */
-class SideEffectOperandNode extends Node instanceof IndirectOperand {
+class SideEffectOperandNode extends Node, IndirectOperand {
   CallInstruction call;
   int argumentIndex;
 
-  SideEffectOperandNode() {
-    IndirectOperand.super.hasOperandAndIndirectionIndex(call.getArgumentOperand(argumentIndex), _)
-  }
+  SideEffectOperandNode() { operand = call.getArgumentOperand(argumentIndex) }
 
   CallInstruction getCallInstruction() { result = call }
 
-  /** Gets the underlying operand and the underlying indirection index. */
-  predicate hasAddressOperandAndIndirectionIndex(Operand operand, int indirectionIndex) {
-    IndirectOperand.super.hasOperandAndIndirectionIndex(operand, indirectionIndex)
-  }
+  Operand getAddressOperand() { result = operand }
 
   int getArgumentIndex() { result = argumentIndex }
 
@@ -670,10 +657,10 @@ class InitialGlobalValue extends Node, TInitialGlobalValue {
  *
  * A node representing an indirection of a parameter.
  */
-class IndirectParameterNode extends Node instanceof IndirectInstruction {
+class IndirectParameterNode extends Node, IndirectInstruction {
   InitializeParameterInstruction init;
 
-  IndirectParameterNode() { IndirectInstruction.super.hasInstructionAndIndirectionIndex(init, _) }
+  IndirectParameterNode() { this.getInstruction() = init }
 
   int getArgumentIndex() { init.hasIndex(result) }
 
@@ -682,12 +669,7 @@ class IndirectParameterNode extends Node instanceof IndirectInstruction {
 
   override Declaration getEnclosingCallable() { result = this.getFunction() }
 
-  override Declaration getFunction() { result = init.getEnclosingFunction() }
-
-  /** Gets the underlying operand and the underlying indirection index. */
-  predicate hasInstructionAndIndirectionIndex(Instruction instr, int index) {
-    IndirectInstruction.super.hasInstructionAndIndirectionIndex(instr, index)
-  }
+  override Declaration getFunction() { result = this.getInstruction().getEnclosingFunction() }
 
   override Location getLocationImpl() { result = this.getParameter().getLocation() }
 
@@ -709,8 +691,7 @@ class IndirectReturnNode extends Node {
   IndirectReturnNode() {
     this instanceof FinalParameterNode
     or
-    this.(IndirectOperand)
-        .hasOperandAndIndirectionIndex(any(ReturnValueInstruction ret).getReturnAddressOperand(), _)
+    this.(IndirectOperand).getOperand() = any(ReturnValueInstruction ret).getReturnAddressOperand()
   }
 
   override Declaration getEnclosingCallable() { result = this.getFunction() }
@@ -733,7 +714,7 @@ class IndirectReturnNode extends Node {
   int getIndirectionIndex() {
     result = this.(FinalParameterNode).getIndirectionIndex()
     or
-    this.(IndirectOperand).hasOperandAndIndirectionIndex(_, result)
+    result = this.(IndirectOperand).getIndirectionIndex()
   }
 }
 
@@ -1117,8 +1098,7 @@ predicate exprNodeShouldBeInstruction(Node node, Expr e) {
 /** Holds if `node` should be an `IndirectInstruction` that maps `node.asIndirectExpr()` to `e`. */
 predicate indirectExprNodeShouldBeIndirectInstruction(IndirectInstruction node, Expr e) {
   exists(Instruction instr |
-    node.hasInstructionAndIndirectionIndex(instr, _) and
-    not indirectExprNodeShouldBeIndirectOperand(_, e)
+    instr = node.getInstruction() and not indirectExprNodeShouldBeIndirectOperand(_, e)
   |
     e = instr.(VariableAddressInstruction).getAst().(Expr).getFullyConverted()
     or
@@ -1319,8 +1299,8 @@ pragma[noinline]
 private predicate indirectParameterNodeHasArgumentIndexAndIndex(
   IndirectParameterNode node, int argumentIndex, int indirectionIndex
 ) {
-  node.hasInstructionAndIndirectionIndex(_, indirectionIndex) and
-  node.getArgumentIndex() = argumentIndex
+  node.getArgumentIndex() = argumentIndex and
+  node.getIndirectionIndex() = indirectionIndex
 }
 
 /** A synthetic parameter to model the pointed-to object of a pointer parameter. */
@@ -1491,14 +1471,18 @@ VariableNode variableNode(Variable v) {
  */
 Node uninitializedNode(LocalVariable v) { none() }
 
+pragma[noinline]
 predicate hasOperandAndIndex(IndirectOperand indirectOperand, Operand operand, int indirectionIndex) {
-  indirectOperand.hasOperandAndIndirectionIndex(operand, indirectionIndex)
+  indirectOperand.getOperand() = operand and
+  indirectOperand.getIndirectionIndex() = indirectionIndex
 }
 
+pragma[noinline]
 predicate hasInstructionAndIndex(
   IndirectInstruction indirectInstr, Instruction instr, int indirectionIndex
 ) {
-  indirectInstr.hasInstructionAndIndirectionIndex(instr, indirectionIndex)
+  indirectInstr.getInstruction() = instr and
+  indirectInstr.getIndirectionIndex() = indirectionIndex
 }
 
 cached
@@ -1556,7 +1540,7 @@ private module Cached {
   cached
   predicate simpleLocalFlowStep(Node nodeFrom, Node nodeTo) {
     // Post update node -> Node flow
-    Ssa::postUpdateFlow(nodeFrom, nodeTo)
+    Ssa::ssaFlow(nodeFrom.(PostUpdateNode).getPreUpdateNode(), nodeTo)
     or
     // Def-use/Use-use flow
     Ssa::ssaFlow(nodeFrom, nodeTo)
@@ -1648,15 +1632,8 @@ predicate localInstructionFlow(Instruction e1, Instruction e2) {
   localFlow(instructionNode(e1), instructionNode(e2))
 }
 
-/**
- * INTERNAL: Do not use.
- *
- * Ideally this module would be private, but the `asExprInternal` predicate is
- * needed in `DefaultTaintTrackingImpl`. Once `DefaultTaintTrackingImpl` is gone
- * we can make this module private.
- */
 cached
-module ExprFlowCached {
+private module ExprFlowCached {
   /**
    * Holds if `n` is an indirect operand of a `PointerArithmeticInstruction`, and
    * `e` is the result of loading from the `PointerArithmeticInstruction`.
@@ -1664,7 +1641,8 @@ module ExprFlowCached {
   private predicate isIndirectBaseOfArrayAccess(IndirectOperand n, Expr e) {
     exists(LoadInstruction load, PointerArithmeticInstruction pai |
       pai = load.getSourceAddress() and
-      n.hasOperandAndIndirectionIndex(pai.getLeftOperand(), 1) and
+      pai.getLeftOperand() = n.getOperand() and
+      n.getIndirectionIndex() = 1 and
       e = load.getConvertedResultExpression()
     )
   }
@@ -1706,8 +1684,7 @@ module ExprFlowCached {
    * `x[i]` steps to the expression `x[i - 1]` without traversing the
    * entire chain.
    */
-  cached
-  Expr asExprInternal(Node n) {
+  private Expr asExpr(Node n) {
     isIndirectBaseOfArrayAccess(n, result)
     or
     not isIndirectBaseOfArrayAccess(n, _) and
@@ -1719,7 +1696,7 @@ module ExprFlowCached {
    * dataflow step.
    */
   private predicate localStepFromNonExpr(Node n1, Node n2) {
-    not exists(asExprInternal(n1)) and
+    not exists(asExpr(n1)) and
     localFlowStep(n1, n2)
   }
 
@@ -1730,7 +1707,7 @@ module ExprFlowCached {
   pragma[nomagic]
   private predicate localStepsToExpr(Node n1, Node n2, Expr e2) {
     localStepFromNonExpr*(n1, n2) and
-    e2 = asExprInternal(n2)
+    e2 = asExpr(n2)
   }
 
   /**
@@ -1741,7 +1718,7 @@ module ExprFlowCached {
     exists(Node mid |
       localFlowStep(n1, mid) and
       localStepsToExpr(mid, n2, e2) and
-      e1 = asExprInternal(n1)
+      e1 = asExpr(n1)
     )
   }
 
@@ -1832,20 +1809,6 @@ class Content extends TContent {
   predicate hasLocationInfo(string path, int sl, int sc, int el, int ec) {
     path = "" and sl = 0 and sc = 0 and el = 0 and ec = 0
   }
-
-  /** Gets the indirection index of this `Content`. */
-  abstract int getIndirectionIndex();
-
-  /**
-   * INTERNAL: Do not use.
-   *
-   * Holds if a write to this `Content` implies that `c` is
-   * also cleared.
-   *
-   * For example, a write to a field `f` implies that any content of
-   * the form `*f` is also cleared.
-   */
-  abstract predicate impliesClearOf(Content c);
 }
 
 /** A reference through a non-union instance field. */
@@ -1863,21 +1826,10 @@ class FieldContent extends Content, TFieldContent {
 
   Field getField() { result = f }
 
-  /** Gets the indirection index of this `FieldContent`. */
   pragma[inline]
-  override int getIndirectionIndex() {
+  int getIndirectionIndex() {
     pragma[only_bind_into](result) = pragma[only_bind_out](indirectionIndex)
   }
-
-  override predicate impliesClearOf(Content c) {
-    exists(FieldContent fc |
-      fc = c and
-      fc.getField() = f and
-      // If `this` is `f` then `c` is cleared if it's of the
-      // form `*f`, `**f`, etc.
-      fc.getIndirectionIndex() >= indirectionIndex
-    )
-  }
 }
 
 /** A reference through an instance field of a union. */
@@ -1902,21 +1854,9 @@ class UnionContent extends Content, TUnionContent {
 
   /** Gets the indirection index of this `UnionContent`. */
   pragma[inline]
-  override int getIndirectionIndex() {
+  int getIndirectionIndex() {
     pragma[only_bind_into](result) = pragma[only_bind_out](indirectionIndex)
   }
-
-  override predicate impliesClearOf(Content c) {
-    exists(UnionContent uc |
-      uc = c and
-      uc.getUnion() = u and
-      // If `this` is `u` then `c` is cleared if it's of the
-      // form `*u`, `**u`, etc. (and we ignore `bytes` because
-      // we know the entire union is overwritten because it's a
-      // union).
-      uc.getIndirectionIndex() >= indirectionIndex
-    )
-  }
 }
 
 /**
@@ -1963,38 +1903,7 @@ signature predicate guardChecksSig(IRGuardCondition g, Expr e, boolean branch);
  * in data flow and taint tracking.
  */
 module BarrierGuard<guardChecksSig/3 guardChecks> {
-  /**
-   * Gets an expression node that is safely guarded by the given guard check.
-   *
-   * For example, given the following code:
-   * ```cpp
-   * int x = source();
-   * // ...
-   * if(is_safe_int(x)) {
-   *   sink(x);
-   * }
-   * ```
-   * and the following barrier guard predicate:
-   * ```ql
-   * predicate myGuardChecks(IRGuardCondition g, Expr e, boolean branch) {
-   *   exists(Call call |
-   *     g.getUnconvertedResultExpression() = call and
-   *     call.getTarget().hasName("is_safe_int") and
-   *     e = call.getAnArgument() and
-   *     branch = true
-   *   )
-   * }
-   * ```
-   * implementing `isBarrier` as:
-   * ```ql
-   * predicate isBarrier(DataFlow::Node barrier) {
-   *   barrier = DataFlow::BarrierGuard<myGuardChecks/3>::getABarrierNode()
-   * }
-   * ```
-   * will block flow from `x = source()` to `sink(x)`.
-   *
-   * NOTE: If an indirect expression is tracked, use `getAnIndirectBarrierNode` instead.
-   */
+  /** Gets a node that is safely guarded by the given guard check. */
   ExprNode getABarrierNode() {
     exists(IRGuardCondition g, Expr e, ValueNumber value, boolean edge |
       e = value.getAnInstruction().getConvertedResultExpression() and
@@ -2003,84 +1912,6 @@ module BarrierGuard<guardChecksSig/3 guardChecks> {
       g.controls(result.getBasicBlock(), edge)
     )
   }
-
-  /**
-   * Gets an indirect expression node that is safely guarded by the given guard check.
-   *
-   * For example, given the following code:
-   * ```cpp
-   * int* p;
-   * // ...
-   * *p = source();
-   * if(is_safe_pointer(p)) {
-   *   sink(*p);
-   * }
-   * ```
-   * and the following barrier guard check:
-   * ```ql
-   * predicate myGuardChecks(IRGuardCondition g, Expr e, boolean branch) {
-   *   exists(Call call |
-   *     g.getUnconvertedResultExpression() = call and
-   *     call.getTarget().hasName("is_safe_pointer") and
-   *     e = call.getAnArgument() and
-   *     branch = true
-   *   )
-   * }
-   * ```
-   * implementing `isBarrier` as:
-   * ```ql
-   * predicate isBarrier(DataFlow::Node barrier) {
-   *   barrier = DataFlow::BarrierGuard<myGuardChecks/3>::getAnIndirectBarrierNode()
-   * }
-   * ```
-   * will block flow from `x = source()` to `sink(x)`.
-   *
-   * NOTE: If a non-indirect expression is tracked, use `getABarrierNode` instead.
-   */
-  IndirectExprNode getAnIndirectBarrierNode() { result = getAnIndirectBarrierNode(_) }
-
-  /**
-   * Gets an indirect expression node with indirection index `indirectionIndex` that is
-   * safely guarded by the given guard check.
-   *
-   * For example, given the following code:
-   * ```cpp
-   * int* p;
-   * // ...
-   * *p = source();
-   * if(is_safe_pointer(p)) {
-   *   sink(*p);
-   * }
-   * ```
-   * and the following barrier guard check:
-   * ```ql
-   * predicate myGuardChecks(IRGuardCondition g, Expr e, boolean branch) {
-   *   exists(Call call |
-   *     g.getUnconvertedResultExpression() = call and
-   *     call.getTarget().hasName("is_safe_pointer") and
-   *     e = call.getAnArgument() and
-   *     branch = true
-   *   )
-   * }
-   * ```
-   * implementing `isBarrier` as:
-   * ```ql
-   * predicate isBarrier(DataFlow::Node barrier) {
-   *   barrier = DataFlow::BarrierGuard<myGuardChecks/3>::getAnIndirectBarrierNode(1)
-   * }
-   * ```
-   * will block flow from `x = source()` to `sink(x)`.
-   *
-   * NOTE: If a non-indirect expression is tracked, use `getABarrierNode` instead.
-   */
-  IndirectExprNode getAnIndirectBarrierNode(int indirectionIndex) {
-    exists(IRGuardCondition g, Expr e, ValueNumber value, boolean edge |
-      e = value.getAnInstruction().getConvertedResultExpression() and
-      result.getConvertedExpr(indirectionIndex) = e and
-      guardChecks(g, value.getAnInstruction().getConvertedResultExpression(), edge) and
-      g.controls(result.getBasicBlock(), edge)
-    )
-  }
 }
 
 /**

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DefaultTaintTrackingImpl.qll

@@ -60,7 +60,7 @@ private DataFlow::Node getNodeForSource(Expr source) {
 }
 
 private DataFlow::Node getNodeForExpr(Expr node) {
-  node = DataFlow::ExprFlowCached::asExprInternal(result)
+  result = DataFlow::exprNode(node)
   or
   // Some of the sources in `isUserInput` are intended to match the value of
   // an expression, while others (those modeled below) are intended to match
@@ -221,7 +221,7 @@ private module Cached {
   predicate nodeIsBarrierIn(DataFlow::Node node) {
     // don't use dataflow into taint sources, as this leads to duplicate results.
     exists(Expr source | isUserInput(source, _) |
-      source = DataFlow::ExprFlowCached::asExprInternal(node)
+      node = DataFlow::exprNode(source)
       or
       // This case goes together with the similar (but not identical) rule in
       // `getNodeForSource`.
@@ -448,8 +448,6 @@ module TaintedWithPath {
     }
 
     predicate isBarrierIn(DataFlow::Node node) { nodeIsBarrierIn(node) }
-
-    predicate neverSkip(Node node) { none() }
   }
 
   private module AdjustedFlow = TaintTracking::Global<AdjustedConfig>;

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/PrintIRFieldFlowSteps.qll

@@ -1,38 +0,0 @@
-/**
- * Print the dataflow local store steps in IR dumps.
- */
-
-private import cpp
-private import semmle.code.cpp.ir.IR
-private import semmle.code.cpp.ir.dataflow.internal.DataFlowUtil
-private import semmle.code.cpp.ir.dataflow.internal.DataFlowPrivate
-private import PrintIRUtilities
-
-/** A property provider for local IR dataflow store steps. */
-class FieldFlowPropertyProvider extends IRPropertyProvider {
-  override string getOperandProperty(Operand operand, string key) {
-    exists(PostFieldUpdateNode pfun, Content content |
-      key = "store " + content.toString() and
-      pfun.getPreUpdateNode().(IndirectOperand).hasOperandAndIndirectionIndex(operand, _) and
-      result =
-        strictconcat(string element, Node node |
-          storeStep(node, content, pfun) and
-          element = nodeId(node, _, _)
-        |
-          element, ", "
-        )
-    )
-    or
-    exists(Node node2, Content content |
-      key = "read " + content.toString() and
-      node2.(IndirectOperand).hasOperandAndIndirectionIndex(operand, _) and
-      result =
-        strictconcat(string element, Node node1 |
-          readStep(node1, content, node2) and
-          element = nodeId(node1, _, _)
-        |
-          element, ", "
-        )
-    )
-  }
-}

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/PrintIRLocalFlow.qll

@@ -1,44 +1,119 @@
 private import cpp
+// The `ValueNumbering` library has to be imported right after `cpp` to ensure
+// that the cached IR gets the same checksum here as it does in queries that use
+// `ValueNumbering` without `DataFlow`.
+private import semmle.code.cpp.ir.ValueNumbering
 private import semmle.code.cpp.ir.IR
+private import semmle.code.cpp.ir.dataflow.DataFlow
 private import semmle.code.cpp.ir.dataflow.internal.DataFlowUtil
-private import SsaInternals as Ssa
 private import PrintIRUtilities
 
 /**
  * Gets the local dataflow from other nodes in the same function to this node.
  */
-private string getFromFlow(Node node2, int order1, int order2) {
-  exists(Node node1 |
-    simpleLocalFlowStep(node1, node2) and
-    result = nodeId(node1, order1, order2)
+private string getFromFlow(DataFlow::Node useNode, int order1, int order2) {
+  exists(DataFlow::Node defNode, string prefix |
+    (
+      simpleLocalFlowStep(defNode, useNode) and prefix = ""
+      or
+      any(DataFlow::Configuration cfg).isAdditionalFlowStep(defNode, useNode) and
+      defNode.getEnclosingCallable() = useNode.getEnclosingCallable() and
+      prefix = "+"
+    ) and
+    if defNode.asInstruction() = useNode.asOperand().getAnyDef()
+    then
+      // Shorthand for flow from the def of this operand.
+      result = prefix + "def" and
+      order1 = -1 and
+      order2 = 0
+    else
+      if defNode.asOperand().getUse() = useNode.asInstruction()
+      then
+        // Shorthand for flow from an operand of this instruction
+        result = prefix + defNode.asOperand().getDumpId() and
+        order1 = -1 and
+        order2 = defNode.asOperand().getDumpSortOrder()
+      else result = prefix + nodeId(defNode, order1, order2)
   )
 }
 
 /**
  * Gets the local dataflow from this node to other nodes in the same function.
  */
-private string getToFlow(Node node1, int order1, int order2) {
-  exists(Node node2 |
-    simpleLocalFlowStep(node1, node2) and
-    result = nodeId(node2, order1, order2)
+private string getToFlow(DataFlow::Node defNode, int order1, int order2) {
+  exists(DataFlow::Node useNode, string prefix |
+    (
+      simpleLocalFlowStep(defNode, useNode) and prefix = ""
+      or
+      any(DataFlow::Configuration cfg).isAdditionalFlowStep(defNode, useNode) and
+      defNode.getEnclosingCallable() = useNode.getEnclosingCallable() and
+      prefix = "+"
+    ) and
+    if useNode.asInstruction() = defNode.asOperand().getUse()
+    then
+      // Shorthand for flow to this operand's instruction.
+      result = prefix + "result" and
+      order1 = -1 and
+      order2 = 0
+    else result = prefix + nodeId(useNode, order1, order2)
   )
 }
 
 /**
  * Gets the properties of the dataflow node `node`.
  */
-private string getNodeProperty(Node node, string key) {
+private string getNodeProperty(DataFlow::Node node, string key) {
   // List dataflow into and out of this node. Flow into this node is printed as `src->@`, and flow
   // out of this node is printed as `@->dest`.
   key = "flow" and
   result =
     strictconcat(string flow, boolean to, int order1, int order2 |
-      flow = getFromFlow(node, order1, order2) + "->" + starsForNode(node) + "@" and to = false
+      flow = getFromFlow(node, order1, order2) + "->@" and to = false
       or
-      flow = starsForNode(node) + "@->" + getToFlow(node, order1, order2) and to = true
+      flow = "@->" + getToFlow(node, order1, order2) and to = true
     |
       flow, ", " order by to, order1, order2, flow
     )
+  or
+  // Is this node a dataflow sink?
+  key = "sink" and
+  any(DataFlow::Configuration cfg).isSink(node) and
+  result = "true"
+  or
+  // Is this node a dataflow source?
+  key = "source" and
+  any(DataFlow::Configuration cfg).isSource(node) and
+  result = "true"
+  or
+  // Is this node a dataflow barrier, and if so, what kind?
+  key = "barrier" and
+  result =
+    strictconcat(string kind |
+      any(DataFlow::Configuration cfg).isBarrier(node) and kind = "full"
+      or
+      any(DataFlow::Configuration cfg).isBarrierIn(node) and kind = "in"
+      or
+      any(DataFlow::Configuration cfg).isBarrierOut(node) and kind = "out"
+    |
+      kind, ", "
+    )
+  // or
+  // // Is there partial flow from a source to this node?
+  // // This property will only be emitted if partial flow is enabled by overriding
+  // // `DataFlow::Configuration::explorationLimit()`.
+  // key = "pflow" and
+  // result =
+  //   strictconcat(DataFlow::PartialPathNode sourceNode, DataFlow::PartialPathNode destNode, int dist,
+  //     int order1, int order2 |
+  //     any(DataFlow::Configuration cfg).hasPartialFlow(sourceNode, destNode, dist) and
+  //     destNode.getNode() = node and
+  //     // Only print flow from a source in the same function.
+  //     sourceNode.getNode().getEnclosingCallable() = node.getEnclosingCallable()
+  //   |
+  //     nodeId(sourceNode.getNode(), order1, order2) + "+" + dist.toString(), ", "
+  //     order by
+  //       order1, order2, dist desc
+  //   )
 }
 
 /**
@@ -46,21 +121,16 @@ private string getNodeProperty(Node node, string key) {
  */
 class LocalFlowPropertyProvider extends IRPropertyProvider {
   override string getOperandProperty(Operand operand, string key) {
-    exists(Node node |
-      operand = [node.asOperand(), node.(RawIndirectOperand).getOperand()] and
+    exists(DataFlow::Node node |
+      operand = node.asOperand() and
       result = getNodeProperty(node, key)
     )
   }
 
   override string getInstructionProperty(Instruction instruction, string key) {
-    exists(Node node |
-      instruction = [node.asInstruction(), node.(RawIndirectInstruction).getInstruction()]
-    |
+    exists(DataFlow::Node node |
+      instruction = node.asInstruction() and
       result = getNodeProperty(node, key)
     )
   }
-
-  override predicate shouldPrintOperand(Operand operand) { not Ssa::ignoreOperand(operand) }
-
-  override predicate shouldPrintInstruction(Instruction instr) { not Ssa::ignoreInstruction(instr) }
 }

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/PrintIRStoreSteps.qll

@@ -0,0 +1,33 @@
+/**
+ * Print the dataflow local store steps in IR dumps.
+ */
+
+private import cpp
+// The `ValueNumbering` library has to be imported right after `cpp` to ensure
+// that the cached IR gets the same checksum here as it does in queries that use
+// `ValueNumbering` without `DataFlow`.
+private import semmle.code.cpp.ir.ValueNumbering
+private import semmle.code.cpp.ir.IR
+private import semmle.code.cpp.ir.dataflow.DataFlow
+private import semmle.code.cpp.ir.dataflow.internal.DataFlowUtil
+private import semmle.code.cpp.ir.dataflow.internal.DataFlowPrivate
+private import PrintIRUtilities
+
+/**
+ * Property provider for local IR dataflow store steps.
+ */
+class LocalFlowPropertyProvider extends IRPropertyProvider {
+  override string getInstructionProperty(Instruction instruction, string key) {
+    exists(DataFlow::Node objectNode, Content content |
+      key = "content[" + content.toString() + "]" and
+      instruction = objectNode.asInstruction() and
+      result =
+        strictconcat(string element, DataFlow::Node fieldNode |
+          storeStep(fieldNode, content, objectNode) and
+          element = nodeId(fieldNode, _, _)
+        |
+          element, ", "
+        )
+    )
+  }
+}

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/PrintIRUtilities.qll

@@ -3,62 +3,37 @@
  */
 
 private import cpp
+// The `ValueNumbering` library has to be imported right after `cpp` to ensure
+// that the cached IR gets the same checksum here as it does in queries that use
+// `ValueNumbering` without `DataFlow`.
+private import semmle.code.cpp.ir.ValueNumbering
 private import semmle.code.cpp.ir.IR
-private import semmle.code.cpp.ir.dataflow.internal.DataFlowUtil
-private import semmle.code.cpp.ir.dataflow.internal.DataFlowPrivate
-
-private string stars(int k) {
-  k =
-    [0 .. max([
-            any(RawIndirectInstruction n).getIndirectionIndex(),
-            any(RawIndirectOperand n).getIndirectionIndex()
-          ]
-      )] and
-  (if k = 0 then result = "" else result = "*" + stars(k - 1))
-}
-
-string starsForNode(Node node) {
-  exists(int indirectionIndex |
-    node.(IndirectInstruction).hasInstructionAndIndirectionIndex(_, indirectionIndex) or
-    node.(IndirectOperand).hasOperandAndIndirectionIndex(_, indirectionIndex)
-  |
-    result = stars(indirectionIndex)
-  )
-  or
-  not node instanceof IndirectInstruction and
-  not node instanceof IndirectOperand and
-  result = ""
-}
-
-private Instruction getInstruction(Node n, string stars) {
-  result = [n.asInstruction(), n.(RawIndirectInstruction).getInstruction()] and
-  stars = starsForNode(n)
-}
-
-private Operand getOperand(Node n, string stars) {
-  result = [n.asOperand(), n.(RawIndirectOperand).getOperand()] and
-  stars = starsForNode(n)
-}
+private import semmle.code.cpp.ir.dataflow.DataFlow
 
 /**
  * Gets a short ID for an IR dataflow node.
  * - For `Instruction`s, this is just the result ID of the instruction (e.g. `m128`).
  * - For `Operand`s, this is the label of the operand, prefixed with the result ID of the
  *   instruction and a dot (e.g. `m128.left`).
+ * - For `Variable`s, this is the qualified name of the variable.
  */
-string nodeId(Node node, int order1, int order2) {
-  exists(Instruction instruction, string stars | instruction = getInstruction(node, stars) |
-    result = stars + instruction.getResultId() and
+string nodeId(DataFlow::Node node, int order1, int order2) {
+  exists(Instruction instruction | instruction = node.asInstruction() |
+    result = instruction.getResultId() and
     order1 = instruction.getBlock().getDisplayIndex() and
     order2 = instruction.getDisplayIndexInBlock()
   )
   or
-  exists(Operand operand, Instruction instruction, string stars |
-    operand = getOperand(node, stars) and
+  exists(Operand operand, Instruction instruction |
+    operand = node.asOperand() and
     instruction = operand.getUse()
   |
-    result = stars + instruction.getResultId() + "." + operand.getDumpId() and
+    result = instruction.getResultId() + "." + operand.getDumpId() and
     order1 = instruction.getBlock().getDisplayIndex() and
     order2 = instruction.getDisplayIndexInBlock()
   )
+  or
+  result = "var(" + node.asVariable().getQualifiedName() + ")" and
+  order1 = 1000000 and
+  order2 = 0
 }

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/SsaInternals.qll

@@ -145,14 +145,14 @@ private newtype TDefOrUseImpl =
       or
       // Since the pruning stage doesn't know about global variables we can't use the above check to
       // rule out dead assignments to globals.
-      base.(VariableAddressInstruction).getAstVariable() instanceof GlobalLikeVariable
+      base.(VariableAddressInstruction).getAstVariable() instanceof Cpp::GlobalOrNamespaceVariable
     )
   } or
   TUseImpl(Operand operand, int indirectionIndex) {
     isUse(_, operand, _, _, indirectionIndex) and
     not isDef(_, _, operand, _, _, _)
   } or
-  TGlobalUse(GlobalLikeVariable v, IRFunction f, int indirectionIndex) {
+  TGlobalUse(Cpp::GlobalOrNamespaceVariable v, IRFunction f, int indirectionIndex) {
     // Represents a final "use" of a global variable to ensure that
     // the assignment to a global variable isn't ruled out as dead.
     exists(VariableAddressInstruction vai, int defIndex |
@@ -162,7 +162,7 @@ private newtype TDefOrUseImpl =
       indirectionIndex = [0 .. defIndex] + 1
     )
   } or
-  TGlobalDefImpl(GlobalLikeVariable v, IRFunction f, int indirectionIndex) {
+  TGlobalDefImpl(Cpp::GlobalOrNamespaceVariable v, IRFunction f, int indirectionIndex) {
     // Represents the initial "definition" of a global variable when entering
     // a function body.
     exists(VariableAddressInstruction vai |
@@ -364,25 +364,7 @@ abstract private class OperandBasedUse extends UseImpl {
   OperandBasedUse() { any() }
 
   final override predicate hasIndexInBlock(IRBlock block, int index) {
-    // See the comment in `ssa0`'s `OperandBasedUse` for an explanation of this
-    // predicate's implementation.
-    exists(BaseSourceVariableInstruction base | base = this.getBase() |
-      if base.getAst() = any(Cpp::PostfixCrementOperation c).getOperand()
-      then
-        exists(Operand op, int indirectionIndex, int indirection |
-          indirectionIndex = this.getIndirectionIndex() and
-          indirection = this.getIndirection() and
-          op =
-            min(Operand cand, int i |
-              isUse(_, cand, base, indirection, indirectionIndex) and
-              block.getInstruction(i) = cand.getUse()
-            |
-              cand order by i
-            ) and
-          block.getInstruction(index) = op.getUse()
-        )
-      else operand.getUse() = block.getInstruction(index)
-    )
+    operand.getUse() = block.getInstruction(index)
   }
 
   final Operand getOperand() { result = operand }
@@ -476,7 +458,7 @@ class FinalParameterUse extends UseImpl, TFinalParameterUse {
 }
 
 class GlobalUse extends UseImpl, TGlobalUse {
-  GlobalLikeVariable global;
+  Cpp::GlobalOrNamespaceVariable global;
   IRFunction f;
 
   GlobalUse() { this = TGlobalUse(global, f, ind) }
@@ -486,7 +468,7 @@ class GlobalUse extends UseImpl, TGlobalUse {
   override int getIndirection() { result = ind + 1 }
 
   /** Gets the global variable associated with this use. */
-  GlobalLikeVariable getVariable() { result = global }
+  Cpp::GlobalOrNamespaceVariable getVariable() { result = global }
 
   /** Gets the `IRFunction` whose body is exited from after this use. */
   IRFunction getIRFunction() { result = f }
@@ -514,14 +496,14 @@ class GlobalUse extends UseImpl, TGlobalUse {
 }
 
 class GlobalDefImpl extends DefOrUseImpl, TGlobalDefImpl {
-  GlobalLikeVariable global;
+  Cpp::GlobalOrNamespaceVariable global;
   IRFunction f;
   int indirectionIndex;
 
   GlobalDefImpl() { this = TGlobalDefImpl(global, f, indirectionIndex) }
 
   /** Gets the global variable associated with this definition. */
-  GlobalLikeVariable getVariable() { result = global }
+  Cpp::GlobalOrNamespaceVariable getVariable() { result = global }
 
   /** Gets the `IRFunction` whose body is evaluated after this definition. */
   IRFunction getIRFunction() { result = f }
@@ -675,20 +657,27 @@ private predicate indirectConversionFlowStep(Node nFrom, Node nTo) {
  * So this predicate recurses back along conversions and `PointerArithmeticInstruction`s to find the
  * first use that has provides use-use flow, and uses that target as the target of the `nodeFrom`.
  */
-private predicate adjustForPointerArith(PostUpdateNode pun, UseOrPhi use) {
-  exists(DefOrUse defOrUse, Node adjusted |
-    indirectConversionFlowStep*(adjusted, pun.getPreUpdateNode()) and
-    nodeToDefOrUse(adjusted, defOrUse, _) and
+private predicate adjustForPointerArith(
+  DefOrUse defOrUse, Node nodeFrom, UseOrPhi use, boolean uncertain
+) {
+  nodeFrom = any(PostUpdateNode pun).getPreUpdateNode() and
+  exists(Node adjusted |
+    indirectConversionFlowStep*(adjusted, nodeFrom) and
+    nodeToDefOrUse(adjusted, defOrUse, uncertain) and
     adjacentDefRead(defOrUse, use)
   )
 }
 
 private predicate ssaFlowImpl(SsaDefOrUse defOrUse, Node nodeFrom, Node nodeTo, boolean uncertain) {
+  // `nodeFrom = any(PostUpdateNode pun).getPreUpdateNode()` is implied by adjustedForPointerArith.
   exists(UseOrPhi use |
+    adjustForPointerArith(defOrUse, nodeFrom, use, uncertain) and
+    useToNode(use, nodeTo)
+    or
+    not nodeFrom = any(PostUpdateNode pun).getPreUpdateNode() and
     nodeToDefOrUse(nodeFrom, defOrUse, uncertain) and
     adjacentDefRead(defOrUse, use) and
-    useToNode(use, nodeTo) and
-    nodeFrom != nodeTo
+    useToNode(use, nodeTo)
     or
     // Initial global variable value to a first use
     nodeFrom.(InitialGlobalValue).getGlobalDef() = defOrUse and
@@ -723,28 +712,11 @@ private Node getAPriorDefinition(SsaDefOrUse defOrUse) {
 /** Holds if there is def-use or use-use flow from `nodeFrom` to `nodeTo`. */
 predicate ssaFlow(Node nodeFrom, Node nodeTo) {
   exists(Node nFrom, boolean uncertain, SsaDefOrUse defOrUse |
-    ssaFlowImpl(defOrUse, nFrom, nodeTo, uncertain) and nodeFrom != nodeTo
-  |
+    ssaFlowImpl(defOrUse, nFrom, nodeTo, uncertain) and
     if uncertain = true then nodeFrom = [nFrom, getAPriorDefinition(defOrUse)] else nodeFrom = nFrom
   )
 }
 
-private predicate isArgumentOfCallable(DataFlowCall call, ArgumentNode arg) {
-  arg.argumentOf(call, _)
-}
-
-/** Holds if there is def-use or use-use flow from `pun` to `nodeTo`. */
-predicate postUpdateFlow(PostUpdateNode pun, Node nodeTo) {
-  exists(UseOrPhi use, Node preUpdate |
-    adjustForPointerArith(pun, use) and
-    useToNode(use, nodeTo) and
-    preUpdate = pun.getPreUpdateNode() and
-    not exists(DataFlowCall call |
-      isArgumentOfCallable(call, preUpdate) and isArgumentOfCallable(call, nodeTo)
-    )
-  )
-}
-
 /**
  * Holds if `use` is a use of `sv` and is a next adjacent use of `phi` in
  * index `i1` in basic block `bb1`.
@@ -770,7 +742,6 @@ predicate fromPhiNode(SsaPhiNode nodeFrom, Node nodeTo) {
     fromPhiNodeToUse(phi, sv, bb1, i1, use)
     or
     exists(PhiNode phiTo |
-      phi != phiTo and
       lastRefRedefExt(phi, _, _, phiTo) and
       nodeTo.(SsaPhiNode).getPhiNode() = phiTo
     )
@@ -789,14 +760,13 @@ private predicate variableWriteCand(IRBlock bb, int i, SourceVariable v) {
 }
 
 private predicate sourceVariableIsGlobal(
-  SourceVariable sv, GlobalLikeVariable global, IRFunction func, int indirectionIndex
+  SourceVariable sv, Cpp::GlobalOrNamespaceVariable global, IRFunction func, int indirectionIndex
 ) {
   exists(IRVariable irVar, BaseIRVariable base |
     sourceVariableHasBaseAndIndex(sv, base, indirectionIndex) and
     irVar = base.getIRVariable() and
     irVar.getEnclosingIRFunction() = func and
-    global = irVar.getAst() and
-    not irVar instanceof IRDynamicInitializationFlag
+    global = irVar.getAst()
   )
 }
 
@@ -949,7 +919,7 @@ class GlobalDef extends TGlobalDef, SsaDefOrUse {
   IRFunction getIRFunction() { result = global.getIRFunction() }
 
   /** Gets the global variable associated with this definition. */
-  GlobalLikeVariable getVariable() { result = global.getVariable() }
+  Cpp::GlobalOrNamespaceVariable getVariable() { result = global.getVariable() }
 }
 
 class Phi extends TPhi, SsaDefOrUse {
@@ -1027,14 +997,6 @@ class PhiNode extends SsaImpl::DefinitionExt {
     this instanceof SsaImpl::PhiNode or
     this instanceof SsaImpl::PhiReadNode
   }
-
-  /**
-   * Holds if this phi node is a phi-read node.
-   *
-   * Phi-read nodes are like normal phi nodes, but they are inserted based
-   * on reads instead of writes.
-   */
-  predicate isPhiRead() { this instanceof SsaImpl::PhiReadNode }
 }
 
 class DefinitionExt = SsaImpl::DefinitionExt;

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/SsaInternalsCommon.qll

@@ -117,16 +117,6 @@ private int countIndirections(Type t) {
   else (
     result = any(Indirection ind | ind.getType() = t).getNumberOfIndirections()
     or
-    // If there is an indirection for the type, but we cannot count the number of indirections
-    // it means we couldn't reach a non-indirection type by stripping off indirections. This
-    // can occur if an iterator specifies itself as the value type. In this case we default to
-    // 1 indirection fore the type.
-    exists(Indirection ind |
-      ind.getType() = t and
-      not exists(ind.getNumberOfIndirections()) and
-      result = 1
-    )
-    or
     not exists(Indirection ind | ind.getType() = t) and
     result = 0
   )
@@ -154,20 +144,6 @@ class AllocationInstruction extends CallInstruction {
   AllocationInstruction() { this.getStaticCallTarget() instanceof Cpp::AllocationFunction }
 }
 
-private predicate isIndirectionType(Type t) { t instanceof Indirection }
-
-private predicate hasUnspecifiedBaseType(Indirection t, Type base) {
-  base = t.getBaseType().getUnspecifiedType()
-}
-
-/**
- * Holds if `t2` is the same type as `t1`, but after stripping away `result` number
- * of indirections.
- * Furthermore, specifies in `t2` been deeply stripped and typedefs has been resolved.
- */
-private int getNumberOfIndirectionsImpl(Type t1, Type t2) =
-  shortestDistances(isIndirectionType/1, hasUnspecifiedBaseType/2)(t1, t2, result)
-
 /**
  * An abstract class for handling indirections.
  *
@@ -186,10 +162,7 @@ abstract class Indirection extends Type {
    * For example, the number of indirections of a variable `p` of type
    * `int**` is `3` (i.e., `p`, `*p` and `**p`).
    */
-  final int getNumberOfIndirections() {
-    result =
-      getNumberOfIndirectionsImpl(this.getType(), any(Type end | not end instanceof Indirection))
-  }
+  abstract int getNumberOfIndirections();
 
   /**
    * Holds if `deref` is an instruction that behaves as a `LoadInstruction`
@@ -227,11 +200,19 @@ private class PointerOrArrayOrReferenceTypeIndirection extends Indirection insta
   PointerOrArrayOrReferenceTypeIndirection() {
     baseType = PointerOrArrayOrReferenceType.super.getBaseType()
   }
+
+  override int getNumberOfIndirections() {
+    result = 1 + countIndirections(this.getBaseType().getUnspecifiedType())
+  }
 }
 
 private class PointerWrapperTypeIndirection extends Indirection instanceof PointerWrapper {
   PointerWrapperTypeIndirection() { baseType = PointerWrapper.super.getBaseType() }
 
+  override int getNumberOfIndirections() {
+    result = 1 + countIndirections(this.getBaseType().getUnspecifiedType())
+  }
+
   override predicate isAdditionalDereference(Instruction deref, Operand address) {
     exists(CallInstruction call |
       operandForFullyConvertedCall(getAUse(deref), call) and
@@ -252,6 +233,10 @@ private module IteratorIndirections {
       baseType = super.getValueType()
     }
 
+    override int getNumberOfIndirections() {
+      result = 1 + countIndirections(this.getBaseType().getUnspecifiedType())
+    }
+
     override predicate isAdditionalDereference(Instruction deref, Operand address) {
       exists(CallInstruction call |
         operandForFullyConvertedCall(getAUse(deref), call) and
@@ -273,7 +258,7 @@ private module IteratorIndirections {
         // Taint through `operator+=` and `operator-=` on iterators.
         call.getStaticCallTarget() instanceof Iterator::IteratorAssignArithmeticOperator and
         node2.(IndirectArgumentOutNode).getPreUpdateNode() = node1 and
-        node1.(IndirectOperand).hasOperandAndIndirectionIndex(call.getArgumentOperand(0), _) and
+        node1.(IndirectOperand).getOperand() = call.getArgumentOperand(0) and
         node1.getType().getUnspecifiedType() = this
       )
     }
@@ -588,6 +573,7 @@ private module Cached {
     )
   }
 
+  pragma[assume_small_delta]
   private predicate convertsIntoArgumentRev(Instruction instr) {
     convertsIntoArgumentFwd(instr) and
     (
@@ -805,7 +791,7 @@ private module Cached {
       address.getDef() = instr and
       isDereference(load, address) and
       isUseImpl(address, _, indirectionIndex - 1) and
-      result = load
+      result = instr
     )
   }
 

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/TaintTrackingUtil.qll

@@ -160,7 +160,7 @@ predicate modeledTaintStep(DataFlow::Node nodeIn, DataFlow::Node nodeOut) {
     FunctionInput modelIn, FunctionOutput modelOut
   |
     indirectArgument = callInput(call, modelIn) and
-    indirectArgument.hasAddressOperandAndIndirectionIndex(nodeIn.asOperand(), _) and
+    indirectArgument.getAddressOperand() = nodeIn.asOperand() and
     call.getStaticCallTarget() = func and
     (
       func.(DataFlowFunction).hasDataFlow(modelIn, modelOut)

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/ssa0/SsaInternals.qll

@@ -122,46 +122,7 @@ abstract private class OperandBasedUse extends UseImpl {
   override string toString() { result = operand.toString() }
 
   final override predicate hasIndexInBlock(IRBlock block, int index) {
-    // Ideally, this would just be implemented as:
-    // ```
-    // operand.getUse() = block.getInstruction(index)
-    // ```
-    // but because the IR generated for a snippet such as
-    // ```
-    // int x = *p++;
-    // ```
-    // looks like
-    // ```
-    // r1(glval<int>)   = VariableAddress[x]  :
-    // r2(glval<int *>) = VariableAddress[p]  :
-    // r3(int *)        = Load[p]             : &:r2, m1
-    // r4(int)          = Constant[1]         :
-    // r5(int *)        = PointerAdd[4]       : r3, r4
-    // m3(int *)        = Store[p]            : &:r2, r5
-    // r6(int *)        = CopyValue           : r3
-    // r7(int)          = Load[?]             : &:r6, ~m2
-    // m2(int)          = Store[x]            : &:r1, r7
-    // ```
-    // we need to ensure that the `r3` operand of the `CopyValue` instruction isn't seen as a fresh use
-    // of `p` that happens after the increment. So if the base instruction of this use comes from a
-    // post-fix crement operation we set the index of the SSA use that wraps the `r3` operand at the
-    // `CopyValue` instruction to be the same index as the `r3` operand at the `PointerAdd` instruction.
-    // This ensures that the SSA library doesn't create flow from the `PointerAdd` to `r6`.
-    exists(BaseSourceVariableInstruction base | base = this.getBase() |
-      if base.getAst() = any(Cpp::PostfixCrementOperation c).getOperand()
-      then
-        exists(Operand op |
-          op =
-            min(Operand cand, int i |
-              isUse(_, cand, base, _, _) and
-              block.getInstruction(i) = cand.getUse()
-            |
-              cand order by i
-            ) and
-          block.getInstruction(index) = op.getUse()
-        )
-      else operand.getUse() = block.getInstruction(index)
-    )
+    operand.getUse() = block.getInstruction(index)
   }
 
   final override Cpp::Location getLocation() { result = operand.getLocation() }

cpp/ql/lib/semmle/code/cpp/ir/implementation/IRType.qll

@@ -39,7 +39,7 @@ class IRType extends TIRType {
    * Gets a string that uniquely identifies this `IRType`. This string is often the same as the
    * result of `IRType.toString()`, but for some types it may be more verbose to ensure uniqueness.
    */
-  string getIdentityString() { result = this.toString() }
+  string getIdentityString() { result = toString() }
 
   /**
    * Gets the size of the type, in bytes, if known.
@@ -206,7 +206,7 @@ class IRFloatingPointType extends IRNumericType, TIRFloatingPointType {
   IRFloatingPointType() { this = TIRFloatingPointType(_, base, domain) }
 
   final override string toString() {
-    result = this.getDomainPrefix() + this.getBaseString() + byteSize.toString()
+    result = getDomainPrefix() + getBaseString() + byteSize.toString()
   }
 
   final override Language::LanguageType getCanonicalLanguageType() {

cpp/ql/lib/semmle/code/cpp/ir/implementation/Opcode.qll

@@ -135,11 +135,11 @@ class Opcode extends TOpcode {
    * Holds if the instruction must have an operand with the specified `OperandTag`.
    */
   final predicate hasOperand(OperandTag tag) {
-    this.hasOperandInternal(tag)
+    hasOperandInternal(tag)
     or
-    this.hasAddressOperand() and tag instanceof AddressOperandTag
+    hasAddressOperand() and tag instanceof AddressOperandTag
     or
-    this.hasBufferSizeOperand() and tag instanceof BufferSizeOperandTag
+    hasBufferSizeOperand() and tag instanceof BufferSizeOperandTag
   }
 
   /**

cpp/ql/lib/semmle/code/cpp/ir/implementation/aliased_ssa/IR.qll

@@ -77,16 +77,4 @@ class IRPropertyProvider extends TIRPropertyProvider {
    * Gets the value of the property named `key` for the specified operand.
    */
   string getOperandProperty(Operand operand, string key) { none() }
-
-  /**
-   * Holds if the instruction `instr` should be included when printing
-   * the IR instructions.
-   */
-  predicate shouldPrintInstruction(Instruction instr) { any() }
-
-  /**
-   * Holds if the operand `operand` should be included when printing the an
-   * instruction's operand list.
-   */
-  predicate shouldPrintOperand(Operand operand) { any() }
 }

cpp/ql/lib/semmle/code/cpp/ir/implementation/aliased_ssa/IRFunction.qll

@@ -45,9 +45,7 @@ class IRFunction extends IRFunctionBase {
    * Gets the block containing the entry point of this function.
    */
   pragma[noinline]
-  final IRBlock getEntryBlock() {
-    result.getFirstInstruction() = this.getEnterFunctionInstruction()
-  }
+  final IRBlock getEntryBlock() { result.getFirstInstruction() = getEnterFunctionInstruction() }
 
   /**
    * Gets all instructions in this function.

cpp/ql/lib/semmle/code/cpp/ir/implementation/aliased_ssa/IRVariable.qll

@@ -39,12 +39,12 @@ class IRVariable extends TIRVariable {
   /**
    * Gets the type of the variable.
    */
-  final Language::Type getType() { this.getLanguageType().hasType(result, false) }
+  final Language::Type getType() { getLanguageType().hasType(result, false) }
 
   /**
    * Gets the language-neutral type of the variable.
    */
-  final IRType getIRType() { result = this.getLanguageType().getIRType() }
+  final IRType getIRType() { result = getLanguageType().getIRType() }
 
   /**
    * Gets the type of the variable.
@@ -58,7 +58,7 @@ class IRVariable extends TIRVariable {
   Language::AST getAst() { none() }
 
   /** DEPRECATED: Alias for getAst */
-  deprecated Language::AST getAST() { result = this.getAst() }
+  deprecated Language::AST getAST() { result = getAst() }
 
   /**
    * Gets an identifier string for the variable. This identifier is unique
@@ -69,7 +69,7 @@ class IRVariable extends TIRVariable {
   /**
    * Gets the source location of this variable.
    */
-  final Language::Location getLocation() { result = this.getAst().getLocation() }
+  final Language::Location getLocation() { result = getAst().getLocation() }
 
   /**
    * Gets the IR for the function that references this variable.
@@ -91,15 +91,15 @@ class IRUserVariable extends IRVariable, TIRUserVariable {
 
   IRUserVariable() { this = TIRUserVariable(var, type, func) }
 
-  final override string toString() { result = this.getVariable().toString() }
+  final override string toString() { result = getVariable().toString() }
 
   final override Language::AST getAst() { result = var }
 
   /** DEPRECATED: Alias for getAst */
-  deprecated override Language::AST getAST() { result = this.getAst() }
+  deprecated override Language::AST getAST() { result = getAst() }
 
   final override string getUniqueId() {
-    result = this.getVariable().toString() + " " + this.getVariable().getLocation().toString()
+    result = getVariable().toString() + " " + getVariable().getLocation().toString()
   }
 
   final override Language::LanguageType getLanguageType() { result = type }
@@ -166,9 +166,9 @@ class IRGeneratedVariable extends IRVariable {
   final override Language::AST getAst() { result = ast }
 
   /** DEPRECATED: Alias for getAst */
-  deprecated override Language::AST getAST() { result = this.getAst() }
+  deprecated override Language::AST getAST() { result = getAst() }
 
-  override string toString() { result = this.getBaseString() + this.getLocationString() }
+  override string toString() { result = getBaseString() + getLocationString() }
 
   override string getUniqueId() { none() }
 
@@ -272,7 +272,7 @@ class IRStringLiteral extends IRGeneratedVariable, TIRStringLiteral {
   final override predicate isReadOnly() { any() }
 
   final override string getUniqueId() {
-    result = "String: " + this.getLocationString() + "=" + Language::getStringLiteralText(literal)
+    result = "String: " + getLocationString() + "=" + Language::getStringLiteralText(literal)
   }
 
   final override string getBaseString() { result = "#string" }
@@ -303,8 +303,7 @@ class IRDynamicInitializationFlag extends IRGeneratedVariable, TIRDynamicInitial
   final Language::Variable getVariable() { result = var }
 
   final override string getUniqueId() {
-    result =
-      "Init: " + this.getVariable().toString() + " " + this.getVariable().getLocation().toString()
+    result = "Init: " + getVariable().toString() + " " + getVariable().getLocation().toString()
   }
 
   final override string getBaseString() { result = "#init:" + var.toString() + ":" }
@@ -333,5 +332,5 @@ class IRParameter extends IRAutomaticVariable {
  * An IR variable representing a positional parameter.
  */
 class IRPositionalParameter extends IRParameter, IRAutomaticUserVariable {
-  final override int getIndex() { result = this.getVariable().(Language::Parameter).getIndex() }
+  final override int getIndex() { result = getVariable().(Language::Parameter).getIndex() }
 }

cpp/ql/lib/semmle/code/cpp/ir/implementation/aliased_ssa/Instruction.qll

@@ -210,6 +210,9 @@ class Instruction extends Construction::TStageInstruction {
    */
   final Language::AST getAst() { result = Construction::getInstructionAst(this) }
 
+  /** DEPRECATED: Alias for getAst */
+  deprecated Language::AST getAST() { result = this.getAst() }
+
   /**
    * Gets the location of the source code for this instruction.
    */
@@ -460,6 +463,9 @@ class VariableInstruction extends Instruction {
    * Gets the AST variable that this instruction's IR variable refers to, if one exists.
    */
   final Language::Variable getAstVariable() { result = var.(IRUserVariable).getVariable() }
+
+  /** DEPRECATED: Alias for getAstVariable */
+  deprecated Language::Variable getASTVariable() { result = this.getAstVariable() }
 }
 
 /**

cpp/ql/lib/semmle/code/cpp/ir/implementation/aliased_ssa/PrintIR.qll

@@ -42,14 +42,6 @@ private predicate shouldPrintFunction(Language::Declaration decl) {
   exists(PrintIRConfiguration config | config.shouldPrintFunction(decl))
 }
 
-private predicate shouldPrintInstruction(Instruction i) {
-  exists(IRPropertyProvider provider | provider.shouldPrintInstruction(i))
-}
-
-private predicate shouldPrintOperand(Operand operand) {
-  exists(IRPropertyProvider provider | provider.shouldPrintOperand(operand))
-}
-
 private string getAdditionalInstructionProperty(Instruction instr, string key) {
   exists(IRPropertyProvider provider | result = provider.getInstructionProperty(instr, key))
 }
@@ -92,9 +84,7 @@ private string getOperandPropertyString(Operand operand) {
 private newtype TPrintableIRNode =
   TPrintableIRFunction(IRFunction irFunc) { shouldPrintFunction(irFunc.getFunction()) } or
   TPrintableIRBlock(IRBlock block) { shouldPrintFunction(block.getEnclosingFunction()) } or
-  TPrintableInstruction(Instruction instr) {
-    shouldPrintInstruction(instr) and shouldPrintFunction(instr.getEnclosingFunction())
-  }
+  TPrintableInstruction(Instruction instr) { shouldPrintFunction(instr.getEnclosingFunction()) }
 
 /**
  * A node to be emitted in the IR graph.
@@ -137,13 +127,13 @@ abstract private class PrintableIRNode extends TPrintableIRNode {
    * Gets the value of the node property with the specified key.
    */
   string getProperty(string key) {
-    key = "semmle.label" and result = this.getLabel()
+    key = "semmle.label" and result = getLabel()
     or
-    key = "semmle.order" and result = this.getOrder().toString()
+    key = "semmle.order" and result = getOrder().toString()
     or
-    key = "semmle.graphKind" and result = this.getGraphKind()
+    key = "semmle.graphKind" and result = getGraphKind()
     or
-    key = "semmle.forceText" and this.forceText() and result = "true"
+    key = "semmle.forceText" and forceText() and result = "true"
   }
 }
 
@@ -188,7 +178,7 @@ private class PrintableIRBlock extends PrintableIRNode, TPrintableIRBlock {
 
   PrintableIRBlock() { this = TPrintableIRBlock(block) }
 
-  override string toString() { result = this.getLabel() }
+  override string toString() { result = getLabel() }
 
   override Language::Location getLocation() { result = block.getLocation() }
 
@@ -233,7 +223,7 @@ private class PrintableInstruction extends PrintableIRNode, TPrintableInstructio
       |
         resultString = instr.getResultString() and
         operationString = instr.getOperationString() and
-        operandsString = this.getOperandsString() and
+        operandsString = getOperandsString() and
         columnWidths(block, resultWidth, operationWidth) and
         result =
           resultString + getPaddingString(resultWidth - resultString.length()) + " = " +
@@ -262,8 +252,7 @@ private class PrintableInstruction extends PrintableIRNode, TPrintableInstructio
   private string getOperandsString() {
     result =
       concat(Operand operand |
-        operand = instr.getAnOperand() and
-        shouldPrintOperand(operand)
+        operand = instr.getAnOperand()
       |
         operand.getDumpString() + getOperandPropertyString(operand), ", "
         order by