New testcase for memmove -> memcpy transform

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16931 91177308-0d34-0410-b5e6-96231b3b80d8

test/Transforms/InstCombine/memmove.ll

@@ -0,0 +1,23 @@
+; This test makes sure that memmove instructions are properly eliminated.
+;
+
+; RUN: llvm-as < %s | opt -instcombine | llvm-dis | not grep 'call void %llvm.memmove'
+
+%S = internal constant [33 x sbyte] c"panic: restorelist inconsistency\00"
+
+implementation
+
+declare void %llvm.memmove(sbyte*, sbyte*, uint, uint)
+
+void %test1(sbyte* %A, sbyte* %B, uint %N) {
+ 	;; 0 bytes -> noop.
+	call void %llvm.memmove(sbyte* %A, sbyte* %B, uint 0, uint 1)
+	ret void
+}
+
+void %test2(sbyte *%A, uint %N) {
+ 	;; dest can't alias source since we can't write to source!
+	call void %llvm.memmove(sbyte* %A, sbyte* getelementptr ([33 x sbyte]* %S, int 0, int 0), 
+                                uint %N, uint 1)
+	ret void
+}