From 66d0884954a4d3caa8146b39fbb6e31af8304020 Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Mon, 15 Mar 2004 04:17:53 +0000
Subject: [PATCH] Make sure that pure calls don't kill loads

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12416 91177308-0d34-0410-b5e6-96231b3b80d8
---
 test/Analysis/LoadVN/call_pure_function.ll | 13 +++++++++++++
 1 file changed, 13 insertions(+)
 create mode 100644 test/Analysis/LoadVN/call_pure_function.ll

diff --git a/test/Analysis/LoadVN/call_pure_function.ll b/test/Analysis/LoadVN/call_pure_function.ll
new file mode 100644
index 00000000000..c9de486c066
--- /dev/null
+++ b/test/Analysis/LoadVN/call_pure_function.ll
@@ -0,0 +1,13 @@
+; RUN: llvm-as < %s | 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
+}