From 58c8670ab2372e6549a4f18619ffcdee2d60093e Mon Sep 17 00:00:00 2001
From: Cameron Zwarich <zwarich@apple.com>
Date: Thu, 10 Feb 2011 01:07:54 +0000
Subject: [PATCH] Turn this pass ordering:

Natural Loop Information
 Loop Pass Manager
   Canonicalize natural loops
 Scalar Evolution Analysis
 Loop Pass Manager
   Induction Variable Users
   Canonicalize natural loops
   Induction Variable Users
   Loop Strength Reduction

into this:

Scalar Evolution Analysis
Loop Pass Manager
  Canonicalize natural loops
  Induction Variable Users
  Loop Strength Reduction

This fixes <rdar://problem/8869639>. I also filed PR9184 on doing this sort of
thing automatically, but it seems easier to just change the ordering of the
passes if this is the only case.

llvm-svn: 125254
---
 llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
index 01dcfaf06527..dcee08b52381 100644
--- a/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
@@ -3815,15 +3815,15 @@ LoopStrengthReduce::LoopStrengthReduce(const TargetLowering *tli)
 void LoopStrengthReduce::getAnalysisUsage(AnalysisUsage &AU) const {
   // We split critical edges, so we change the CFG.  However, we do update
   // many analyses if they are around.
-  AU.addPreservedID(LoopSimplifyID);
 
-  AU.addRequired<LoopInfo>();
-  AU.addPreserved<LoopInfo>();
-  AU.addRequiredID(LoopSimplifyID);
   AU.addRequired<DominatorTree>();
   AU.addPreserved<DominatorTree>();
   AU.addRequired<ScalarEvolution>();
   AU.addPreserved<ScalarEvolution>();
+  AU.addRequired<LoopInfo>();
+  AU.addPreserved<LoopInfo>();
+  AU.addRequiredID(LoopSimplifyID);
+  AU.addPreservedID(LoopSimplifyID);
   AU.addRequired<IVUsers>();
   AU.addPreserved<IVUsers>();
 }