1 files changed, 13 insertions, 0 deletions
diff --git a/llvm/test/Analysis/LoadVN/call_pure_function.ll b/llvm/test/Analysis/LoadVN/call_pure_function.ll
new file mode 100644
index 00000000000..302ae604663
--- /dev/null
+++ b/llvm/test/Analysis/LoadVN/call_pure_function.ll
@@ -0,0 +1,13 @@
+; RUN: llvm-upgrade < %s | llvm-as | opt -basicaa -load-vn -gcse -instcombine | llvm-dis | not grep sub
+declare int %strlen(sbyte*)
+declare void %use(int %X)
+
+sbyte %test(sbyte* %P, sbyte* %Q) {
+	%A = load sbyte* %Q
+	%X = call int %strlen(sbyte* %P)
+	%B = load sbyte* %Q                ;; CSE with A.
+	call void %use(int %X)             ;; make strlen not dead
+
+	%C = sub sbyte %A, %B
+	ret sbyte %C
+}