From 6092dc54550217336e9a13eb0f7121984c1251cb Mon Sep 17 00:00:00 2001
From: Michael Ilseman <milseman@apple.com>
Date: Thu, 7 Feb 2013 23:01:35 +0000
Subject: [PATCH] Have InstCombine call SipmlifyCall when handling calls. Test
 case included.

llvm-svn: 174675
---
 llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp |  6 ++++++
 llvm/test/Transforms/InstCombine/intrinsics.ll       | 16 ++++++++++++++--
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
index 64cd1bd..cb9ba44 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -13,6 +13,7 @@
 
 #include "InstCombine.h"
 #include "llvm/ADT/Statistic.h"
+#include "llvm/Analysis/InstructionSimplify.h"
 #include "llvm/Analysis/MemoryBuiltins.h"
 #include "llvm/IR/DataLayout.h"
 #include "llvm/Support/CallSite.h"
@@ -210,6 +211,11 @@ Instruction *InstCombiner::visitCallInst(CallInst &CI) {
     return &CI;
   }
 
+  CallSite CS(&CI);
+  if (Value *V = SimplifyCall(CS.getCalledValue(), CS.arg_begin(), CS.arg_end(),
+                              TD))
+    return ReplaceInstUsesWith(CI, V);
+
   IntrinsicInst *II = dyn_cast<IntrinsicInst>(&CI);
   if (!II) return visitCallSite(&CI);
 
diff --git a/llvm/test/Transforms/InstCombine/intrinsics.ll b/llvm/test/Transforms/InstCombine/intrinsics.ll
index f334b3b..6bfea72 100644
--- a/llvm/test/Transforms/InstCombine/intrinsics.ll
+++ b/llvm/test/Transforms/InstCombine/intrinsics.ll
@@ -152,8 +152,8 @@ entry:
   ret void
 ; CHECK: @powi
 ; CHECK: %A = fdiv double 1.0{{.*}}, %V
-; CHECK: store volatile double %A, 
-; CHECK: store volatile double 1.0 
+; CHECK: store volatile double %A,
+; CHECK: store volatile double 1.0
 ; CHECK: store volatile double %V
 }
 
@@ -256,3 +256,15 @@ define i32 @cttz_select(i32 %Value) nounwind {
 ; CHECK: @cttz_select
 ; CHECK: select i1 %tobool, i32 %cttz, i32 32
 }
+
+; Test that SimplifyCall is getting invoked by InstCombine
+declare float @llvm.fabs.f32(float) nounwind readnone
+define float @simplify_idempotent(float %a) {
+; CHECK: @simplify_idempotent
+; CHECK: fabs
+; CHECK-NOT: fabs
+  %a0 = call float @llvm.fabs.f32(float %a)
+  %a1 = call float @llvm.fabs.f32(float %a0)
+
+  ret float %a1
+}
\ No newline at end of file
-- 
2.7.4