Merge pull request #15458 from MathiasVP/dataflow-node-deduplication

C++: Fix more `asExpr` duplication

Author: MathiasVP

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

@@ -1408,7 +1408,10 @@ private class InstructionExprNode extends ExprNodeBase, InstructionNode {
   InstructionExprNode() {
     exists(Expr e, int n |
       exprNodeShouldBeInstruction(this, e, n) and
-      not exprNodeShouldBe(e, n + 1)
+      not exists(Expr conv |
+        exprNodeShouldBe(conv, n + 1) and
+        conv.getUnconverted() = e.getUnconverted()
+      )
     )
   }
 
@@ -1419,7 +1422,10 @@ private class OperandExprNode extends ExprNodeBase, OperandNode {
   OperandExprNode() {
     exists(Expr e, int n |
       exprNodeShouldBeOperand(this, e, n) and
-      not exprNodeShouldBe(e, n + 1)
+      not exists(Expr conv |
+        exprNodeShouldBe(conv, n + 1) and
+        conv.getUnconverted() = e.getUnconverted()
+      )
     )
   }
 

cpp/ql/test/library-tests/dataflow/asExpr/test.cpp

@@ -2,7 +2,7 @@ void take_const_ref_int(const int &);
 
 void test_materialize_temp_int()
 {
-  take_const_ref_int(42); // $ asExpr=42 numberOfNodes="42: 2" asIndirectExpr=42
+  take_const_ref_int(42); // $ asExpr=42 asIndirectExpr=42
 }
 
 struct A {};
@@ -11,7 +11,7 @@ A get();
 void take_const_ref(const A &);
 
 void test1(){
-  take_const_ref(get()); // $ asExpr="call to get" numberOfNodes="call to get: 2" asIndirectExpr="call to get"
+  take_const_ref(get()); // $ asExpr="call to get" asIndirectExpr="call to get"
 }
 
 void take_ref(A &);

cpp/ql/test/library-tests/string_concat/strconcat.expected

@@ -1,9 +1,6 @@
 | concat.cpp:23:27:23:27 | call to operator+ | concat.cpp:23:22:23:25 | str1 | concat.cpp:23:22:23:31 | call to operator+ |
-| concat.cpp:23:27:23:27 | call to operator+ | concat.cpp:23:22:23:25 | str1 | concat.cpp:23:27:23:27 | call to operator+ |
 | concat.cpp:23:27:23:27 | call to operator+ | concat.cpp:23:29:23:31 |   | concat.cpp:23:22:23:31 | call to operator+ |
-| concat.cpp:23:27:23:27 | call to operator+ | concat.cpp:23:29:23:31 |   | concat.cpp:23:27:23:27 | call to operator+ |
 | concat.cpp:23:33:23:33 | call to operator+ | concat.cpp:23:35:23:38 | str2 | concat.cpp:23:22:23:38 | call to operator+ |
-| concat.cpp:23:33:23:33 | call to operator+ | concat.cpp:23:35:23:38 | str2 | concat.cpp:23:33:23:33 | call to operator+ |
 | concat.cpp:23:40:23:40 | call to operator+ | concat.cpp:23:42:23:45 | str3 | concat.cpp:23:40:23:40 | call to operator+ |
 | concat.cpp:47:8:47:8 | call to operator<< | concat.cpp:47:11:47:14 | str1 | concat.cpp:47:8:47:17 | call to operator<< |
 | concat.cpp:47:16:47:16 | call to operator<< | concat.cpp:47:19:47:21 |   | concat.cpp:47:16:47:24 | call to operator<< |