From 5cf5fd2ffac088b19348dcc6a048b1d4976ed5a0 Mon Sep 17 00:00:00 2001
From: Benjamin Kramer <benny.kra@googlemail.com>
Date: Tue, 16 Mar 2010 19:36:43 +0000
Subject: [PATCH] Mark str[r]chr readonly.

llvm-svn: 98663
---
 llvm/lib/Transforms/Scalar/SimplifyLibCalls.cpp | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/llvm/lib/Transforms/Scalar/SimplifyLibCalls.cpp b/llvm/lib/Transforms/Scalar/SimplifyLibCalls.cpp
index 05027ae528e3..9e263ddf91ba 100644
--- a/llvm/lib/Transforms/Scalar/SimplifyLibCalls.cpp
+++ b/llvm/lib/Transforms/Scalar/SimplifyLibCalls.cpp
@@ -1400,6 +1400,15 @@ bool SimplifyLibCalls::doInitialization(Module &M) {
           setOnlyReadsMemory(F);
           setDoesNotThrow(F);
           setDoesNotCapture(F, 1);
+        } else if (Name == "strchr" ||
+                   Name == "strrchr") {
+          if (FTy->getNumParams() != 2 ||
+              !FTy->getParamType(0)->isPointerTy() ||
+              !FTy->getParamType(1)->isIntegerTy())
+            continue;
+          setOnlyReadsMemory(F);
+          setDoesNotThrow(F);
+          setDoesNotCapture(F, 1);
         } else if (Name == "strcpy" ||
                    Name == "stpcpy" ||
                    Name == "strcat" ||
@@ -1428,7 +1437,7 @@ bool SimplifyLibCalls::doInitialization(Module &M) {
         } else if (Name == "strcmp" ||
                    Name == "strspn" ||
                    Name == "strncmp" ||
-                   Name ==" strcspn" ||
+                   Name == "strcspn" ||
                    Name == "strcoll" ||
                    Name == "strcasecmp" ||
                    Name == "strncasecmp") {