From 03de2a621c2f063294eb3f65ea1136f3acac4e98 Mon Sep 17 00:00:00 2001 From: Peter Collingbourne Date: Thu, 10 Jan 2013 22:36:33 +0000 Subject: [PATCH] [msan] Change va_start/va_copy shadow memset alignment to 8. This fixes va_start/va_copy of a va_list field which happens to not be laid out at a 16-byte boundary. Differential Revision: http://llvm-reviews.chandlerc.com/D276 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172128 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Instrumentation/MemorySanitizer.cpp | 4 ++-- test/Instrumentation/MemorySanitizer/msan_basic.ll | 13 +++++++++++++ 2 files changed, 15 insertions(+), 2 deletions(-) diff --git a/lib/Transforms/Instrumentation/MemorySanitizer.cpp b/lib/Transforms/Instrumentation/MemorySanitizer.cpp index 58d5801ea08..76da9706829 100644 --- a/lib/Transforms/Instrumentation/MemorySanitizer.cpp +++ b/lib/Transforms/Instrumentation/MemorySanitizer.cpp @@ -1774,7 +1774,7 @@ struct VarArgAMD64Helper : public VarArgHelper { // Unpoison the whole __va_list_tag. // FIXME: magic ABI constants. IRB.CreateMemSet(ShadowPtr, Constant::getNullValue(IRB.getInt8Ty()), - /* size */24, /* alignment */16, false); + /* size */24, /* alignment */8, false); } void visitVACopyInst(VACopyInst &I) { @@ -1785,7 +1785,7 @@ struct VarArgAMD64Helper : public VarArgHelper { // Unpoison the whole __va_list_tag. // FIXME: magic ABI constants. IRB.CreateMemSet(ShadowPtr, Constant::getNullValue(IRB.getInt8Ty()), - /* size */ 24, /* alignment */ 16, false); + /* size */24, /* alignment */8, false); } void finalizeInstrumentation() { diff --git a/test/Instrumentation/MemorySanitizer/msan_basic.ll b/test/Instrumentation/MemorySanitizer/msan_basic.ll index 20957fb36f4..cd90f8836aa 100644 --- a/test/Instrumentation/MemorySanitizer/msan_basic.ll +++ b/test/Instrumentation/MemorySanitizer/msan_basic.ll @@ -534,3 +534,16 @@ define <8 x i8*> @VectorOfPointers(<8 x i8*>* %p) nounwind uwtable { ; CHECK: load <8 x i8*>* ; CHECK: store <8 x i64> {{.*}} @__msan_retval_tls ; CHECK: ret <8 x i8*> + +; Test handling of va_copy. + +declare void @llvm.va_copy(i8*, i8*) nounwind + +define void @VACopy(i8* %p1, i8* %p2) nounwind uwtable { + call void @llvm.va_copy(i8* %p1, i8* %p2) nounwind + ret void +} + +; CHECK: @VACopy +; CHECK: call void @llvm.memset.p0i8.i64({{.*}}, i8 0, i64 24, i32 8, i1 false) +; CHECK: ret void -- 2.34.1