From: Mark Heffernan <meheff@google.com>
Date: Tue, 4 Nov 2014 01:51:01 +0000 (+0000)
Subject: Remove setPreservesCFG from instcombine.  The pass, in particular, does not
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=2e25042a937e0e2762c8ef35a3a30ec8f9930406;p=platform%2Fupstream%2Fllvm.git

Remove setPreservesCFG from instcombine.  The pass, in particular, does not
preserve LoopSimplify because instcombine may replace branch predicates
with undef which loop simplify then replaces with always exit.  Replace
setPreservesCFG with the more constrained preservation of DomTree and
LoopInfo.

llvm-svn: 221223
---

diff --git a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
index 5a0b01e..4b7f841 100644
--- a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -90,7 +90,8 @@ INITIALIZE_PASS_END(InstCombiner, "instcombine",
                 "Combine redundant instructions", false, false)
 
 void InstCombiner::getAnalysisUsage(AnalysisUsage &AU) const {
-  AU.setPreservesCFG();
+  AU.addPreserved<DominatorTreeWrapperPass>();
+  AU.addPreserved<LoopInfo>();
   AU.addRequired<AssumptionTracker>();
   AU.addRequired<TargetLibraryInfo>();
 }