From c4e2a52dc365a30c0ba672b2725fd09d355f563b Mon Sep 17 00:00:00 2001
From: Calum Grant <calumgrant@github.com>
Date: Wed, 29 May 2024 15:56:57 +0100
Subject: [PATCH] WIP

---
 cpp/ql/lib/experimental/buildless/ast.qll     | 12 +++++-
 .../experimental/buildless/compiled_ast.qll   | 39 +++++++++++++------
 cpp/ql/lib/experimental/buildless/test.ql     |  6 +++
 3 files changed, 44 insertions(+), 13 deletions(-)

diff --git a/cpp/ql/lib/experimental/buildless/ast.qll b/cpp/ql/lib/experimental/buildless/ast.qll
index ebb7476f8a4..7c9d167c2ba 100644
--- a/cpp/ql/lib/experimental/buildless/ast.qll
+++ b/cpp/ql/lib/experimental/buildless/ast.qll
@@ -59,13 +59,23 @@ module Buildless<BuildlessASTSig AST> {
   class AccessExpr extends Expr
   {
     string identifier;
-    
+
     AccessExpr() { AST::accessExpr(this, identifier) }
 
     string getName() { result = identifier }
 
     override string toString() { result = this.getName() }
   }
+
+  class CallExpr extends Expr
+  {
+    CallExpr() { AST::callExpr(this) }
+
+    Expr getReceiver() { AST::callReceiver(this, result) }
+    Expr getArgument(int i) { AST::callArgument(this, i, result) }
+
+    override string toString() { result = "...(...)" }
+  }
 }
 
 module TestAST = Buildless<CompiledAST>;
diff --git a/cpp/ql/lib/experimental/buildless/compiled_ast.qll b/cpp/ql/lib/experimental/buildless/compiled_ast.qll
index 6aba0176b72..9517c090f1a 100644
--- a/cpp/ql/lib/experimental/buildless/compiled_ast.qll
+++ b/cpp/ql/lib/experimental/buildless/compiled_ast.qll
@@ -10,7 +10,8 @@ module CompiledAST implements BuildlessASTSig {
     // TFunction(SourceLocation loc) { exists(Function f | f.getLocation() = loc) } or
     TStatement(SourceLocation loc) { exists(Stmt s | s.getLocation() = loc) } or
     TDeclaration(SourceLocation loc) { exists(DeclarationEntry decl | decl.getLocation() = loc) } or
-    TExpression(SourceLocation loc) { exists(Expr e | e.getLocation() = loc) }
+    TExpression(SourceLocation loc) { exists(Expr e | e.getLocation() = loc) } or
+    TFunctionCallName(SourceLocation loc) { exists(FunctionCall c | c.getLocation() = loc) }
 
   class Node extends TNode {
     string toString() { result = "node" }
@@ -18,16 +19,19 @@ module CompiledAST implements BuildlessASTSig {
     Location getLocation() {
       this = TStatement(result) or
       this = TDeclaration(result) or
-      this = TExpression(result)
+      this = TExpression(result) or
+      this = TFunctionCallName(result)
     }
 
-    Stmt getStmt() { result.getLocation() = this.getLocation() }
+    Stmt getStmt() { this = TStatement(result.getLocation()) }
 
     Function getFunction() { result.getLocation() = this.getLocation() }
 
-    DeclarationEntry getDeclaration() { result.getLocation() = this.getLocation() }
+    DeclarationEntry getDeclaration() { this = TDeclaration(result.getLocation()) }
 
-    Expr getExpr() { result.getLocation() = this.getLocation() }
+    Expr getExpr() { this = TExpression(result.getLocation()) }
+
+    FunctionCall getFunctionCallName() { this = TFunctionCallName(result.getLocation()) }
   }
 
   predicate nodeLocation(Node node, Location location) { location = node.getLocation() }
@@ -113,7 +117,9 @@ module CompiledAST implements BuildlessASTSig {
   predicate typeParameterDefault(Node templateParameter, Node defaultTypeOrValue) { none() }
 
   // Declarations
-  predicate variableDeclaration(Node decl) { decl.getDeclaration() instanceof VariableDeclarationEntry }
+  predicate variableDeclaration(Node decl) {
+    decl.getDeclaration() instanceof VariableDeclarationEntry
+  }
 
   predicate variableDeclarationType(Node decl, Node type) { none() }
 
@@ -121,7 +127,9 @@ module CompiledAST implements BuildlessASTSig {
 
   predicate variableDeclarationEntryInitializer(Node entry, Node initializer) { none() }
 
-  predicate variableName(Node decl, string name) { decl.getDeclaration().(VariableDeclarationEntry).getName() = name }
+  predicate variableName(Node decl, string name) {
+    decl.getDeclaration().(VariableDeclarationEntry).getName() = name
+  }
 
   predicate ptrEntry(Node entry, Node element) { none() }
 
@@ -132,7 +140,7 @@ module CompiledAST implements BuildlessASTSig {
   predicate arrayEntry(Node entry, Node element) { none() }
 
   // Expressions
-  predicate expression(Node node) { exists(node.getExpr()) }
+  predicate expression(Node node) { exists(node.getExpr()) or exists(node.getFunctionCallName()) }
 
   predicate prefixExpr(Node expr, string operator, Node operand) { none() }
 
@@ -142,11 +150,18 @@ module CompiledAST implements BuildlessASTSig {
 
   predicate castExpr(Node expr, Node type, Node operand) { none() }
 
-  predicate callExpr(Node call) { none() }
+  predicate callExpr(Node call) { call.getExpr() instanceof Call }
 
-  predicate callArgument(Node call, int i, Node arg) { none() }
+  predicate callArgument(Node call, int i, Node arg) {
+    arg.getExpr() = call.getExpr().(Call).getArgument(i)
+  }
 
-  predicate callReceiver(Node call, Node receiver) { none() }
+  predicate callReceiver(Node call, Node receiver) {
+    receiver.getFunctionCallName() = call.getExpr()
+  }
 
-  predicate accessExpr(Node expr, string name) { expr.getExpr().(VariableAccess).getTarget().getName() = name }
+  predicate accessExpr(Node expr, string name) {
+    expr.getExpr().(VariableAccess).getTarget().getName() = name or
+    expr.getFunctionCallName().getTarget().getName() = name
+  }
 }
diff --git a/cpp/ql/lib/experimental/buildless/test.ql b/cpp/ql/lib/experimental/buildless/test.ql
index c9e49d78983..eea6b245e57 100644
--- a/cpp/ql/lib/experimental/buildless/test.ql
+++ b/cpp/ql/lib/experimental/buildless/test.ql
@@ -15,6 +15,12 @@ query predicate variables(TestAST::VariableDeclaration v)
     any()
 }
 
+query predicate naiveCallTargets(TestAST::CallExpr call, TestAST::SourceFunction target)
+{
+    call.getReceiver().(TestAST::AccessExpr).getName() = target.getName()
+
+    and target.getName() = "max"
+}
 
 from TestAST::SourceFunction fn, int i
 // where fn.getName() = "lua_copy" and i=0