[analyzer] handle modification of vars inside an expr with comma operator

We should track mutation of a variable within a comma operator expression.
Current code in ExprMutationAnalyzer does not handle it.

This will handle cases like:

(a, b) ++ < == b is modified
(a, b) = c < == b is modifed


Patch by Djordje Todorovic.

Differential Revision: https://reviews.llvm.org/D58894


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@355605 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 131 insertions, 0 deletions

diff --git a/unittests/Analysis/ExprMutationAnalyzerTest.cpp b/unittests/Analysis/ExprMutationAnalyzerTest.cpp
index 871c915149..c8ddc48fa7 100644
--- a/unittests/Analysis/ExprMutationAnalyzerTest.cpp
+++ b/unittests/Analysis/ExprMutationAnalyzerTest.cpp
@@ -881,6 +881,137 @@ TEST(ExprMutationAnalyzerTest, CastToConstRef) {
   EXPECT_FALSE(isMutated(Results, AST.get()));
 }
 
+TEST(ExprMutationAnalyzerTest, CommaExprWithAnAssigment) {
+  const auto AST =
+      buildASTFromCodeWithArgs("void f() { int x; int y; (x, y) = 5; }",
+                               {"-Wno-unused-value"});
+  const auto Results =
+      match(withEnclosingCompound(declRefTo("y")), AST->getASTContext());
+  EXPECT_TRUE(isMutated(Results, AST.get()));
+}
+
+TEST(ExprMutationAnalyzerTest, CommaExprWithDecOp) {
+  const auto AST =
+      buildASTFromCodeWithArgs("void f() { int x; int y; (x, y)++; }",
+                               {"-Wno-unused-value"});
+  const auto Results =
+      match(withEnclosingCompound(declRefTo("y")), AST->getASTContext());
+  EXPECT_TRUE(isMutated(Results, AST.get()));
+}
+
+TEST(ExprMutationAnalyzerTest, CommaExprWithNonConstMemberCall) {
+  const auto AST =
+      buildASTFromCodeWithArgs("class A { public: int mem; void f() { mem ++; } };"
+                               "void fn() { A o1, o2; (o1, o2).f(); }",
+                               {"-Wno-unused-value"});
+  const auto Results =
+      match(withEnclosingCompound(declRefTo("o2")), AST->getASTContext());
+  EXPECT_TRUE(isMutated(Results, AST.get()));
+}
+
+TEST(ExprMutationAnalyzerTest, CommaExprWithConstMemberCall) {
+  const auto AST =
+      buildASTFromCodeWithArgs("class A { public: int mem; void f() const  { } };"
+                               "void fn() { A o1, o2; (o1, o2).f(); }",
+                               {"-Wno-unused-value"});
+  const auto Results =
+      match(withEnclosingCompound(declRefTo("o2")), AST->getASTContext());
+  EXPECT_FALSE(isMutated(Results, AST.get()));
+}
+
+TEST(ExprMutationAnalyzerTest, CommaExprWithCallExpr) {
+  const auto AST =
+      buildASTFromCodeWithArgs("class A { public: int mem; void f(A &O1) {} };"
+                               "void fn() { A o1, o2; o2.f((o2, o1)); }",
+                               {"-Wno-unused-value"});
+  const auto Results =
+      match(withEnclosingCompound(declRefTo("o1")), AST->getASTContext());
+  EXPECT_TRUE(isMutated(Results, AST.get()));
+}
+
+TEST(ExprMutationAnalyzerTest, CommaExprWithCallUnresolved) {
+  auto AST = buildASTFromCodeWithArgs(
+      "template <class T> struct S;"
+      "template <class T> void f() { S<T> s; int x, y; s.mf((y, x)); }",
+      {"-fno-delayed-template-parsing -Wno-unused-value"});
+  auto Results =
+      match(withEnclosingCompound(declRefTo("x")), AST->getASTContext());
+  EXPECT_TRUE(isMutated(Results, AST.get()));
+
+  AST = buildASTFromCodeWithArgs(
+      "template <class T> void f(T t) { int x, y; g(t, (y, x)); }",
+      {"-fno-delayed-template-parsing -Wno-unused-value"});
+  Results = match(withEnclosingCompound(declRefTo("x")), AST->getASTContext());
+  EXPECT_TRUE(isMutated(Results, AST.get()));
+}
+
+TEST(ExprMutationAnalyzerTest, CommaExprParmRef) {
+  const auto AST =
+      buildASTFromCodeWithArgs("class A { public: int mem;};"
+                               "extern void fn(A &o1);"
+                               "void fn2 () { A o1, o2; fn((o2, o1)); } ",
+                               {"-Wno-unused-value"});
+  const auto Results =
+      match(withEnclosingCompound(declRefTo("o1")), AST->getASTContext());
+  EXPECT_TRUE(isMutated(Results, AST.get()));
+}
+
+TEST(ExprMutationAnalyzerTest, CommaExprWithAmpersandOp) {
+  const auto AST =
+      buildASTFromCodeWithArgs("class A { public: int mem;};"
+                               "void fn () { A o1, o2;"
+                               "void *addr = &(o2, o1); } ",
+                               {"-Wno-unused-value"});
+  const auto Results =
+      match(withEnclosingCompound(declRefTo("o1")), AST->getASTContext());
+  EXPECT_TRUE(isMutated(Results, AST.get()));
+}
+
+TEST(ExprMutationAnalyzerTest, CommaExprAsReturnAsValue) {
+  auto AST = buildASTFromCodeWithArgs("int f() { int x, y; return (x, y); }",
+                                      {"-Wno-unused-value"});
+  auto Results =
+      match(withEnclosingCompound(declRefTo("y")), AST->getASTContext());
+  EXPECT_FALSE(isMutated(Results, AST.get()));
+}
+
+TEST(ExprMutationAnalyzerTest, CommaEpxrAsReturnAsNonConstRef) {
+  const auto AST =
+      buildASTFromCodeWithArgs("int& f() { int x, y; return (y, x); }",
+                               {"-Wno-unused-value"});
+  const auto Results =
+      match(withEnclosingCompound(declRefTo("x")), AST->getASTContext());
+  EXPECT_TRUE(isMutated(Results, AST.get()));
+}
+
+TEST(ExprMutationAnalyzerTest, CommaExprAsArrayToPointerDecay) {
+  const auto AST =
+      buildASTFromCodeWithArgs("void g(int*); "
+                               "void f() { int x[2], y[2]; g((y, x)); }",
+                               {"-Wno-unused-value"});
+  const auto Results =
+      match(withEnclosingCompound(declRefTo("x")), AST->getASTContext());
+  EXPECT_TRUE(isMutated(Results, AST.get()));
+}
+
+TEST(ExprMutationAnalyzerTest, CommaExprAsUniquePtr) {
+  const std::string UniquePtrDef =
+      "template <class T> struct UniquePtr {"
+      "  UniquePtr();"
+      "  UniquePtr(const UniquePtr&) = delete;"
+      "  T& operator*() const;"
+      "  T* operator->() const;"
+      "};";
+  const auto AST = buildASTFromCodeWithArgs(
+      UniquePtrDef + "template <class T> void f() "
+                     "{ UniquePtr<T> x; UniquePtr<T> y;"
+                     " (y, x)->mf(); }",
+      {"-fno-delayed-template-parsing -Wno-unused-value"});
+  const auto Results =
+      match(withEnclosingCompound(declRefTo("x")), AST->getASTContext());
+  EXPECT_TRUE(isMutated(Results, AST.get()));
+}
+
 TEST(ExprMutationAnalyzerTest, LambdaDefaultCaptureByValue) {
   const auto AST = buildASTFromCode("void f() { int x; [=]() { x; }; }");
   const auto Results =