[llvm-commits] [llvm] r130301 - in /llvm/trunk/lib/Transforms/InstCombine: InstCombine.h InstCombinePHI.cpp InstructionCombining.cpp

[Duncan Sands]

Author: baldrick
Date: Wed Apr 27 05:55:12 2011
New Revision: 130301

URL: http://llvm.org/viewvc/llvm-project?rev=130301&view=rev
Log:
Stop trying to have instcombine preserve LCSSA form: this was not
effective in avoiding recomputation of LCSSA form; the widespread
use of instsimplify (which looks through phi nodes) means it was
not preserving LCSSA form anyway; and instcombine is no longer
scheduled in the middle of the loop passes so this doesn't matter
anymore.

Modified:
    llvm/trunk/lib/Transforms/InstCombine/InstCombine.h
    llvm/trunk/lib/Transforms/InstCombine/InstCombinePHI.cpp
    llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp

Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombine.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombine.h?rev=130301&r1=130300&r2=130301&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombine.h (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombine.h Wed Apr 27 05:55:12 2011
@@ -70,7 +70,6 @@
                              : public FunctionPass,
                                public InstVisitor<InstCombiner, Instruction*> {
   TargetData *TD;
-  bool MustPreserveLCSSA;
   bool MadeIRChange;
 public:
   /// Worklist - All of the instructions that need to be simplified.

Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombinePHI.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombinePHI.cpp?rev=130301&r1=130300&r2=130301&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombinePHI.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombinePHI.cpp Wed Apr 27 05:55:12 2011
@@ -774,9 +774,6 @@
 // PHINode simplification
 //
 Instruction *InstCombiner::visitPHINode(PHINode &PN) {
-  // If LCSSA is around, don't mess with Phi nodes
-  if (MustPreserveLCSSA) return 0;
-
   if (Value *V = SimplifyInstruction(&PN, TD))
     return ReplaceInstUsesWith(PN, V);
 

Modified: llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp?rev=130301&r1=130300&r2=130301&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp Wed Apr 27 05:55:12 2011
@@ -76,7 +76,6 @@
                 "Combine redundant instructions", false, false)
 
 void InstCombiner::getAnalysisUsage(AnalysisUsage &AU) const {
-  AU.addPreservedID(LCSSAID);
   AU.setPreservesCFG();
 }
 
@@ -1637,7 +1636,6 @@
 
 
 bool InstCombiner::runOnFunction(Function &F) {
-  MustPreserveLCSSA = mustPreserveAnalysisID(LCSSAID);
   TD = getAnalysisIfAvailable<TargetData>();