[llvm-branch-commits] [llvm-branch] r113851 - in /llvm/branches/release_28: ./ lib/Transforms/Utils/LoopSimplify.cpp test/Transforms/LoopSimplify/preserve-scev.ll

[Bill Wendling]

Author: void
Date: Tue Sep 14 15:57:16 2010
New Revision: 113851

URL: http://llvm.org/viewvc/llvm-project?rev=113851&view=rev
Log:
Approved by Chris:

$ svn merge -c 113057 https://llvm.org/svn/llvm-project/llvm/trunk
--- Merging r113057 into '.':
A    test/Transforms/LoopSimplify/preserve-scev.ll
U    lib/Transforms/Utils/LoopSimplify.cpp


Added:
    llvm/branches/release_28/test/Transforms/LoopSimplify/preserve-scev.ll
      - copied unchanged from r113057, llvm/trunk/test/Transforms/LoopSimplify/preserve-scev.ll
Modified:
    llvm/branches/release_28/   (props changed)
    llvm/branches/release_28/lib/Transforms/Utils/LoopSimplify.cpp

Propchange: llvm/branches/release_28/
------------------------------------------------------------------------------
--- svn:mergeinfo (original)
+++ svn:mergeinfo Tue Sep 14 15:57:16 2010
@@ -1,2 +1,2 @@
 /llvm/branches/Apple/Pertwee:110850,110961
-/llvm/trunk:113109,113123,113146,113158,113255,113257,113260,113297,113299,113303,113322,113345,113365-113366,113394,113483-113485,113576,113637,113820
+/llvm/trunk:113057,113109,113123,113146,113158,113255,113257,113260,113297,113299,113303,113322,113345,113365-113366,113394,113483-113485,113576,113637,113820

Modified: llvm/branches/release_28/lib/Transforms/Utils/LoopSimplify.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_28/lib/Transforms/Utils/LoopSimplify.cpp?rev=113851&r1=113850&r2=113851&view=diff
==============================================================================
--- llvm/branches/release_28/lib/Transforms/Utils/LoopSimplify.cpp (original)
+++ llvm/branches/release_28/lib/Transforms/Utils/LoopSimplify.cpp Tue Sep 14 15:57:16 2010
@@ -46,6 +46,7 @@
 #include "llvm/LLVMContext.h"
 #include "llvm/Type.h"
 #include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/ScalarEvolution.h"
 #include "llvm/Analysis/Dominators.h"
 #include "llvm/Analysis/LoopPass.h"
 #include "llvm/Transforms/Utils/BasicBlockUtils.h"
@@ -71,6 +72,7 @@
     AliasAnalysis *AA;
     LoopInfo *LI;
     DominatorTree *DT;
+    ScalarEvolution *SE;
     Loop *L;
     virtual bool runOnLoop(Loop *L, LPPassManager &LPM);
 
@@ -83,7 +85,7 @@
       AU.addPreserved<LoopInfo>();
 
       AU.addPreserved<AliasAnalysis>();
-      AU.addPreserved("scalar-evolution");
+      AU.addPreserved<ScalarEvolution>();
       AU.addPreservedID(BreakCriticalEdgesID);  // No critical edges added.
       AU.addPreserved<DominanceFrontier>();
       AU.addPreservedID(LCSSAID);
@@ -121,6 +123,7 @@
   LI = &getAnalysis<LoopInfo>();
   AA = getAnalysisIfAvailable<AliasAnalysis>();
   DT = &getAnalysis<DominatorTree>();
+  SE = getAnalysisIfAvailable<ScalarEvolution>();
 
   Changed |= ProcessLoop(L, LPM);
 
@@ -532,6 +535,12 @@
 
   DEBUG(dbgs() << "LoopSimplify: Splitting out a new outer loop\n");
 
+  // If ScalarEvolution is around and knows anything about values in
+  // this loop, tell it to forget them, because we're about to
+  // substantially change it.
+  if (SE)
+    SE->forgetLoop(L);
+
   BasicBlock *Header = L->getHeader();
   BasicBlock *NewBB = SplitBlockPredecessors(Header, &OuterLoopPreds[0],
                                              OuterLoopPreds.size(),