Author: rnk Date: Wed Oct 7 16:03:41 2015 New Revision: 249616 URL: http://llvm.org/viewvc/llvm-project?rev=249616&view=rev Log: [WinEH] Don't use lifetime markers for MS catch parameters
We don't have a good place to put them. Our previous spot was causing us to optimize loads from the exception object to undef, because it was after the catchpad instruction that models the write to the catch object. Modified: cfe/trunk/lib/CodeGen/CGDecl.cpp cfe/trunk/test/CodeGenCXX/microsoft-abi-eh-catch.cpp Modified: cfe/trunk/lib/CodeGen/CGDecl.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGDecl.cpp?rev=249616&r1=249615&r2=249616&view=diff ============================================================================== --- cfe/trunk/lib/CodeGen/CGDecl.cpp (original) +++ cfe/trunk/lib/CodeGen/CGDecl.cpp Wed Oct 7 16:03:41 2015 @@ -974,9 +974,15 @@ CodeGenFunction::EmitAutoVarAlloca(const address = CreateTempAlloca(allocaTy, allocaAlignment); address.getPointer()->setName(D.getName()); + // Don't emit lifetime markers for MSVC catch parameters. The lifetime of + // the catch parameter starts in the catchpad instruction, and we can't + // insert code in those basic blocks. + bool IsMSCatchParam = + D.isExceptionVariable() && getTarget().getCXXABI().isMicrosoft(); + // Emit a lifetime intrinsic if meaningful. There's no point // in doing this if we don't have a valid insertion point (?). - if (HaveInsertPoint()) { + if (HaveInsertPoint() && !IsMSCatchParam) { uint64_t size = CGM.getDataLayout().getTypeAllocSize(allocaTy); emission.SizeForLifetimeMarkers = EmitLifetimeStart(size, address.getPointer()); Modified: cfe/trunk/test/CodeGenCXX/microsoft-abi-eh-catch.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/microsoft-abi-eh-catch.cpp?rev=249616&r1=249615&r2=249616&view=diff ============================================================================== --- cfe/trunk/test/CodeGenCXX/microsoft-abi-eh-catch.cpp (original) +++ cfe/trunk/test/CodeGenCXX/microsoft-abi-eh-catch.cpp Wed Oct 7 16:03:41 2015 @@ -1,5 +1,6 @@ // RUN: %clang_cc1 -std=c++11 -emit-llvm %s -o - -triple=x86_64-pc-windows-msvc \ // RUN: -mconstructor-aliases -fexceptions -fcxx-exceptions -fnew-ms-eh \ +// RUN: -O1 -disable-llvm-optzns \ // RUN: | FileCheck -check-prefix WIN64 %s extern "C" void might_throw(); @@ -47,8 +48,17 @@ extern "C" void catch_int() { // WIN64-LABEL: define void @catch_int() // WIN64: catchpad [%rtti.TypeDescriptor2* @"\01??_R0H@8", i32 0, i32* %[[e_addr:[^\]]*]]] +// +// The catchpad instruction starts the lifetime of 'e'. Unfortunately, that +// leaves us with nowhere to put lifetime.start, so we don't emit lifetime +// markers for now. +// WIN64-NOT: lifetime.start +// // WIN64: %[[e_i8:[^ ]*]] = bitcast i32* %[[e_addr]] to i8* -// WIN64: call void @handle_exception(i8* %[[e_i8]]) +// WIN64-NOT: lifetime.start +// WIN64: call void @handle_exception +// WIN64-SAME: (i8* %[[e_i8]]) +// WIN64-NOT: lifetime.end // WIN64: catchret extern "C" void catch_int_unnamed() { _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits