MS ABI: Don't push destructor cleanups for aggregate parameters in thunks
The target method of the thunk will perform the cleanup. This can't be
tested in 32-bit x86 yet because passing something by value would create
an inalloca, and we refuse to generate broken code for that.
llvm-svn: 213976
diff --git a/clang/lib/CodeGen/CGDecl.cpp b/clang/lib/CodeGen/CGDecl.cpp
index 91f8041..b42a443 100644
--- a/clang/lib/CodeGen/CGDecl.cpp
+++ b/clang/lib/CodeGen/CGDecl.cpp
@@ -1656,7 +1656,9 @@
DeclPtr = Arg->getType() == IRTy ? Arg : Builder.CreateBitCast(Arg, IRTy,
D.getName());
// Push a destructor cleanup for this parameter if the ABI requires it.
- if (!IsScalar &&
+ // Don't push a cleanup in a thunk for a method that will also emit a
+ // cleanup.
+ if (!IsScalar && !CurFuncIsThunk &&
getTarget().getCXXABI().areArgsDestroyedLeftToRightInCallee()) {
const CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
if (RD && RD->hasNonTrivialDestructor())
diff --git a/clang/lib/CodeGen/CGVTables.cpp b/clang/lib/CodeGen/CGVTables.cpp
index 0df2c43..c53e7ed 100644
--- a/clang/lib/CodeGen/CGVTables.cpp
+++ b/clang/lib/CodeGen/CGVTables.cpp
@@ -194,6 +194,7 @@
const CGFunctionInfo &FnInfo) {
assert(!CurGD.getDecl() && "CurGD was already set!");
CurGD = GD;
+ CurFuncIsThunk = true;
// Build FunctionArgs.
const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
diff --git a/clang/lib/CodeGen/CodeGenFunction.cpp b/clang/lib/CodeGen/CodeGenFunction.cpp
index 5ca3a78..67eae45 100644
--- a/clang/lib/CodeGen/CodeGenFunction.cpp
+++ b/clang/lib/CodeGen/CodeGenFunction.cpp
@@ -38,16 +38,16 @@
Builder(cgm.getModule().getContext(), llvm::ConstantFolder(),
CGBuilderInserterTy(this)),
CapturedStmtInfo(nullptr), SanOpts(&CGM.getLangOpts().Sanitize),
- IsSanitizerScope(false), AutoreleaseResult(false), BlockInfo(nullptr),
- BlockPointer(nullptr), LambdaThisCaptureField(nullptr),
- NormalCleanupDest(nullptr), NextCleanupDestIndex(1),
- FirstBlockInfo(nullptr), EHResumeBlock(nullptr), ExceptionSlot(nullptr),
- EHSelectorSlot(nullptr), DebugInfo(CGM.getModuleDebugInfo()),
- DisableDebugInfo(false), DidCallStackSave(false), IndirectBranch(nullptr),
- PGO(cgm), SwitchInsn(nullptr), SwitchWeights(nullptr),
- CaseRangeBlock(nullptr), UnreachableBlock(nullptr), NumReturnExprs(0),
- NumSimpleReturnExprs(0), CXXABIThisDecl(nullptr),
- CXXABIThisValue(nullptr), CXXThisValue(nullptr),
+ IsSanitizerScope(false), CurFuncIsThunk(false), AutoreleaseResult(false),
+ BlockInfo(nullptr), BlockPointer(nullptr),
+ LambdaThisCaptureField(nullptr), NormalCleanupDest(nullptr),
+ NextCleanupDestIndex(1), FirstBlockInfo(nullptr), EHResumeBlock(nullptr),
+ ExceptionSlot(nullptr), EHSelectorSlot(nullptr),
+ DebugInfo(CGM.getModuleDebugInfo()), DisableDebugInfo(false),
+ DidCallStackSave(false), IndirectBranch(nullptr), PGO(cgm),
+ SwitchInsn(nullptr), SwitchWeights(nullptr), CaseRangeBlock(nullptr),
+ UnreachableBlock(nullptr), NumReturnExprs(0), NumSimpleReturnExprs(0),
+ CXXABIThisDecl(nullptr), CXXABIThisValue(nullptr), CXXThisValue(nullptr),
CXXDefaultInitExprThis(nullptr), CXXStructorImplicitParamDecl(nullptr),
CXXStructorImplicitParamValue(nullptr), OutermostConditional(nullptr),
CurLexicalScope(nullptr), TerminateLandingPad(nullptr),
diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index 335a891..ccf7651 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -258,6 +258,10 @@
~SanitizerScope();
};
+ /// In C++, whether we are code generating a thunk. This controls whether we
+ /// should emit cleanups.
+ bool CurFuncIsThunk;
+
/// In ARC, whether we should autorelease the return value.
bool AutoreleaseResult;