hohn/codeql
1
0
Fork 0
mirror of https://github.com/github/codeql.git synced 2025-12-22 03:36:30 +01:00
Code Issues Packages Projects Releases Wiki Activity

Merge pull request #2755 from jbj/BarrierGuard-SSA

Browse Source 
C++: Don't use GVN in AST DataFlow BarrierNode
This commit is contained in:
Mathias Vorreiter Pedersen
2020-02-04 12:00:12 +01:00
committed by GitHub
parent bd51ef35b7 b4385c6e60
commit 0276c97b9c
4 changed files with 6 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

7
cpp/ql/src/semmle/code/cpp/dataflow/internal/DataFlowUtil.qll
View File

@@ -6,7 +6,6 @@ private import cpp
private import semmle.code.cpp.dataflow.internal.FlowVar
private import semmle.code.cpp.models.interfaces.DataFlow
private import semmle.code.cpp.controlflow.Guards
private import semmle.code.cpp.valuenumbering.GlobalValueNumbering
cached
private newtype TNode =
@@ -689,9 +688,9 @@ class BarrierGuard extends GuardCondition {
/** Gets a node guarded by this guard. */
final ExprNode getAGuardedNode() {
exists(GVN value, boolean branch |
result.getExpr() = value.getAnExpr() and
this.checks(value.getAnExpr(), branch) and
exists(SsaDefinition def, Variable v, boolean branch |
result.getExpr() = def.getAUse(v) and
this.checks(def.getAUse(v), branch) and
this.controls(result.getExpr().getBasicBlock(), branch)
)
}

2
cpp/ql/test/library-tests/dataflow/dataflow-tests/BarrierGuard.cpp
View File

@@ -48,7 +48,7 @@ struct XY {
void bg_stackstruct(XY s1, XY s2) {
s1.x = source();
if (guarded(s1.x)) {
sink(s1.x); // no flow
sink(s1.x); // no flow [FALSE POSITIVE in AST]
} else if (guarded(s1.y)) {
sink(s1.x); // flow
} else if (guarded(s2.y)) {

1
cpp/ql/test/library-tests/dataflow/dataflow-tests/test.expected
View File

@@ -3,6 +3,7 @@
| BarrierGuard.cpp:25:10:25:15 | source | BarrierGuard.cpp:21:17:21:22 | source |
| BarrierGuard.cpp:31:10:31:15 | source | BarrierGuard.cpp:29:16:29:21 | source |
| BarrierGuard.cpp:33:10:33:15 | source | BarrierGuard.cpp:29:16:29:21 | source |
| BarrierGuard.cpp:51:13:51:13 | x | BarrierGuard.cpp:49:10:49:15 | call to source |
| BarrierGuard.cpp:53:13:53:13 | x | BarrierGuard.cpp:49:10:49:15 | call to source |
| BarrierGuard.cpp:55:13:55:13 | x | BarrierGuard.cpp:49:10:49:15 | call to source |
| BarrierGuard.cpp:62:14:62:14 | x | BarrierGuard.cpp:60:11:60:16 | call to source |

1
cpp/ql/test/library-tests/dataflow/dataflow-tests/test_diff.expected
View File

@@ -1,3 +1,4 @@
| BarrierGuard.cpp:49:10:49:15 | BarrierGuard.cpp:51:13:51:13 | AST only |
| BarrierGuard.cpp:60:11:60:16 | BarrierGuard.cpp:62:14:62:14 | AST only |
| clang.cpp:12:9:12:20 | clang.cpp:22:8:22:20 | AST only |
| clang.cpp:28:27:28:32 | clang.cpp:30:27:30:34 | AST only |