Check in LLVM r95781.
diff --git a/test/Analysis/GlobalsModRef/purecse.ll b/test/Analysis/GlobalsModRef/purecse.ll
new file mode 100644
index 0000000..994aff8
--- /dev/null
+++ b/test/Analysis/GlobalsModRef/purecse.ll
@@ -0,0 +1,23 @@
+; Test that pure functions are cse'd away
+; RUN: opt < %s -globalsmodref-aa -gvn -instcombine | \
+; RUN: llvm-dis | not grep sub
+
+define i32 @pure(i32 %X) {
+ %Y = add i32 %X, 1 ; <i32> [#uses=1]
+ ret i32 %Y
+}
+
+define i32 @test1(i32 %X) {
+ %A = call i32 @pure( i32 %X ) ; <i32> [#uses=1]
+ %B = call i32 @pure( i32 %X ) ; <i32> [#uses=1]
+ %C = sub i32 %A, %B ; <i32> [#uses=1]
+ ret i32 %C
+}
+
+define i32 @test2(i32 %X, i32* %P) {
+ %A = call i32 @pure( i32 %X ) ; <i32> [#uses=1]
+ store i32 %X, i32* %P ;; Does not invalidate 'pure' call.
+ %B = call i32 @pure( i32 %X ) ; <i32> [#uses=1]
+ %C = sub i32 %A, %B ; <i32> [#uses=1]
+ ret i32 %C
+}