When extending a memset range past the front, set the alignment of the
memset region to the alignment of the new start address.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81810 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Transforms/MemCpyOpt/align.ll b/test/Transforms/MemCpyOpt/align.ll
new file mode 100644
index 0000000..a9d0337
--- /dev/null
+++ b/test/Transforms/MemCpyOpt/align.ll
@@ -0,0 +1,18 @@
+; RUN: opt < %s -S -memcpyopt | FileCheck %s
+
+; The resulting memset is only 4-byte aligned, despite containing
+; a 16-byte alignmed store in the middle.
+
+; CHECK: call void @llvm.memset.i64(i8* %a01, i8 0, i64 16, i32 4)
+
+define void @foo(i32* %p) {
+ %a0 = getelementptr i32* %p, i64 0
+ store i32 0, i32* %a0, align 4
+ %a1 = getelementptr i32* %p, i64 1
+ store i32 0, i32* %a1, align 16
+ %a2 = getelementptr i32* %p, i64 2
+ store i32 0, i32* %a2, align 4
+ %a3 = getelementptr i32* %p, i64 3
+ store i32 0, i32* %a3, align 4
+ ret void
+}