[llvm-commits] [llvm] r172128 - in /llvm/trunk: lib/Transforms/Instrumentation/MemorySanitizer.cpp test/Instrumentation/MemorySanitizer/msan_basic.ll

[Peter Collingbourne]

Author: pcc
Date: Thu Jan 10 16:36:33 2013
New Revision: 172128

URL: http://llvm.org/viewvc/llvm-project?rev=172128&view=rev
Log:
[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

Modified:
    llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp
    llvm/trunk/test/Instrumentation/MemorySanitizer/msan_basic.ll

Modified: llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp?rev=172128&r1=172127&r2=172128&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp (original)
+++ llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp Thu Jan 10 16:36:33 2013
@@ -1774,7 +1774,7 @@
     // 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 @@
     // 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() {

Modified: llvm/trunk/test/Instrumentation/MemorySanitizer/msan_basic.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Instrumentation/MemorySanitizer/msan_basic.ll?rev=172128&r1=172127&r2=172128&view=diff
==============================================================================
--- llvm/trunk/test/Instrumentation/MemorySanitizer/msan_basic.ll (original)
+++ llvm/trunk/test/Instrumentation/MemorySanitizer/msan_basic.ll Thu Jan 10 16:36:33 2013
@@ -534,3 +534,16 @@
 ; 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