Correctly lower memset / memcpy of undef. It should be a nop. PR6767.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100208 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/CodeGen/X86/memset-2.ll b/test/CodeGen/X86/memset-2.ll
index 702632c..0e15595 100644
--- a/test/CodeGen/X86/memset-2.ll
+++ b/test/CodeGen/X86/memset-2.ll
@@ -1,13 +1,11 @@
-; RUN: llc < %s | FileCheck %s
-
-target triple = "i386"
+; RUN: llc -mtriple=i386-apple-darwin < %s | FileCheck %s
 
 declare void @llvm.memset.i32(i8*, i8, i32, i32) nounwind
 
 define fastcc void @t1() nounwind {
 entry:
 ; CHECK: t1:
-; CHECK: call memset
+; CHECK: call _memset
   call void @llvm.memset.i32( i8* null, i8 0, i32 188, i32 1 ) nounwind
   unreachable
 }
@@ -15,7 +13,7 @@
 define fastcc void @t2(i8 signext %c) nounwind {
 entry:
 ; CHECK: t2:
-; CHECK: call memset
+; CHECK: call _memset
   call void @llvm.memset.i32( i8* undef, i8 %c, i32 76, i32 1 ) nounwind
   unreachable
 }
diff --git a/test/CodeGen/X86/memset-3.ll b/test/CodeGen/X86/memset-3.ll
new file mode 100644
index 0000000..9b20ad5
--- /dev/null
+++ b/test/CodeGen/X86/memset-3.ll
@@ -0,0 +1,12 @@
+; RUN: llc -mtriple=i386-apple-darwin < %s | not grep memset
+; PR6767
+
+define void @t() nounwind ssp {
+entry:
+  %buf = alloca [512 x i8], align 1
+  %ptr = getelementptr inbounds [512 x i8]* %buf, i32 0, i32 0
+  call void @llvm.memset.i32(i8* %ptr, i8 undef, i32 512, i32 1)
+  unreachable
+}
+
+declare void @llvm.memset.i32(i8* nocapture, i8, i32, i32) nounwind