r327352 - [CFG] [analyzer] Don't add construction context to a return-by-reference call.
Artem Dergachev via cfe-commits
cfe-commits at lists.llvm.org
Mon Mar 12 16:52:36 PDT 2018
Author: dergachev
Date: Mon Mar 12 16:52:36 2018
New Revision: 327352
URL: http://llvm.org/viewvc/llvm-project?rev=327352&view=rev
Log:
[CFG] [analyzer] Don't add construction context to a return-by-reference call.
Call expressions that return objects by an lvalue reference or an rvalue
reference have a value type in the AST but wear an auxiliary flag of being an
lvalue or an xvalue respectively.
Use the helper method for obtaining the actual return type of the function.
Fixes a crash.
Differential Revision: https://reviews.llvm.org/D44273
Modified:
cfe/trunk/include/clang/Analysis/CFG.h
cfe/trunk/lib/Analysis/CFG.cpp
cfe/trunk/test/Analysis/temp-obj-dtors-cfg-output.cpp
cfe/trunk/test/Analysis/temporaries.cpp
Modified: cfe/trunk/include/clang/Analysis/CFG.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Analysis/CFG.h?rev=327352&r1=327351&r2=327352&view=diff
==============================================================================
--- cfe/trunk/include/clang/Analysis/CFG.h (original)
+++ cfe/trunk/include/clang/Analysis/CFG.h Mon Mar 12 16:52:36 2018
@@ -183,14 +183,16 @@ class CFGCXXRecordTypedCall : public CFG
public:
/// Returns true when call expression \p CE needs to be represented
/// by CFGCXXRecordTypedCall, as opposed to a regular CFGStmt.
- static bool isCXXRecordTypedCall(CallExpr *CE) {
- return CE->getType().getCanonicalType()->getAsCXXRecordDecl();
+ static bool isCXXRecordTypedCall(CallExpr *CE, const ASTContext &ACtx) {
+ return CE->getCallReturnType(ACtx).getCanonicalType()->getAsCXXRecordDecl();
}
explicit CFGCXXRecordTypedCall(CallExpr *CE,
- const TemporaryObjectConstructionContext *C)
+ const TemporaryObjectConstructionContext *C)
: CFGStmt(CE, CXXRecordTypedCall) {
- assert(isCXXRecordTypedCall(CE));
+ // FIXME: This is not protected against squeezing a non-record-typed-call
+ // into the constructor. An assertion would require passing an ASTContext
+ // which would mean paying for something we don't use.
assert(C);
Data2.setPointer(const_cast<TemporaryObjectConstructionContext *>(C));
}
Modified: cfe/trunk/lib/Analysis/CFG.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Analysis/CFG.cpp?rev=327352&r1=327351&r2=327352&view=diff
==============================================================================
--- cfe/trunk/lib/Analysis/CFG.cpp (original)
+++ cfe/trunk/lib/Analysis/CFG.cpp Mon Mar 12 16:52:36 2018
@@ -751,7 +751,7 @@ private:
void appendCall(CFGBlock *B, CallExpr *CE) {
if (BuildOpts.AddRichCXXConstructors) {
- if (CFGCXXRecordTypedCall::isCXXRecordTypedCall(CE)) {
+ if (CFGCXXRecordTypedCall::isCXXRecordTypedCall(CE, *Context)) {
if (const ConstructionContextLayer *Layer =
ConstructionContextMap.lookup(CE)) {
const ConstructionContext *CC =
@@ -1265,7 +1265,7 @@ void CFGBuilder::findConstructionContext
case Stmt::CXXOperatorCallExprClass:
case Stmt::UserDefinedLiteralClass: {
auto *CE = cast<CallExpr>(Child);
- if (CFGCXXRecordTypedCall::isCXXRecordTypedCall(CE))
+ if (CFGCXXRecordTypedCall::isCXXRecordTypedCall(CE, *Context))
consumeConstructionContext(Layer, CE);
break;
}
Modified: cfe/trunk/test/Analysis/temp-obj-dtors-cfg-output.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Analysis/temp-obj-dtors-cfg-output.cpp?rev=327352&r1=327351&r2=327352&view=diff
==============================================================================
--- cfe/trunk/test/Analysis/temp-obj-dtors-cfg-output.cpp (original)
+++ cfe/trunk/test/Analysis/temp-obj-dtors-cfg-output.cpp Mon Mar 12 16:52:36 2018
@@ -205,6 +205,21 @@ int testConsistencyNestedNormalReturn(bo
return 0;
}
+namespace pass_references_through {
+class C {
+public:
+ ~C() {}
+};
+
+const C &foo1();
+C &&foo2();
+
+// In these examples the foo() expression has record type, not reference type.
+// Don't try to figure out how to perform construction of the record here.
+const C &bar1() { return foo1(); } // no-crash
+C &&bar2() { return foo2(); } // no-crash
+} // end namespace pass_references_through
+
// CHECK: [B1 (ENTRY)]
// CHECK: Succs (1): B0
// CHECK: [B0 (EXIT)]
@@ -1402,3 +1417,29 @@ int testConsistencyNestedNormalReturn(bo
// CHECK: Succs (2): B8 B1
// CHECK: [B0 (EXIT)]
// CHECK: Preds (3): B1 B2 B4
+// CHECK: [B1 (ENTRY)]
+// CHECK: Succs (1): B0
+// CHECK: [B0 (EXIT)]
+// CHECK: Preds (1): B1
+// CHECK: [B2 (ENTRY)]
+// CHECK: Succs (1): B1
+// CHECK: [B1]
+// CHECK: 1: foo1
+// CHECK: 2: [B1.1] (ImplicitCastExpr, FunctionToPointerDecay, const class pass_references_through::C &(*)(void))
+// CHECK: 3: [B1.2]()
+// CHECK: 4: return [B1.3];
+// CHECK: Preds (1): B2
+// CHECK: Succs (1): B0
+// CHECK: [B0 (EXIT)]
+// CHECK: Preds (1): B1
+// CHECK: [B2 (ENTRY)]
+// CHECK: Succs (1): B1
+// CHECK: [B1]
+// CHECK: 1: foo2
+// CHECK: 2: [B1.1] (ImplicitCastExpr, FunctionToPointerDecay, class pass_references_through::C &&(*)(void))
+// CHECK: 3: [B1.2]()
+// CHECK: 4: return [B1.3];
+// CHECK: Preds (1): B2
+// CHECK: Succs (1): B0
+// CHECK: [B0 (EXIT)]
+// CHECK: Preds (1): B1
Modified: cfe/trunk/test/Analysis/temporaries.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Analysis/temporaries.cpp?rev=327352&r1=327351&r2=327352&view=diff
==============================================================================
--- cfe/trunk/test/Analysis/temporaries.cpp (original)
+++ cfe/trunk/test/Analysis/temporaries.cpp Mon Mar 12 16:52:36 2018
@@ -1032,4 +1032,17 @@ void test() {
}
} // end namespace implicit_constructor_conversion
+namespace pass_references_through {
+class C {
+public:
+ ~C() {}
+};
+const C &foo1();
+C &&foo2();
+
+// In these examples the foo() expression has record type, not reference type.
+// Don't try to figure out how to perform construction of the record here.
+const C &bar1() { return foo1(); } // no-crash
+C &&bar2() { return foo2(); } // no-crash
+} // end namespace pass_references_through
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