Don't insert nearly as many redundant phi nodes.

[oota-llvm.git] / lib / Transforms / Scalar / IndVarSimplify.cpp

diff --git a/lib/Transforms/Scalar/IndVarSimplify.cpp b/lib/Transforms/Scalar/IndVarSimplify.cpp
index aad6cc9a5e828e57774fcdfbf64a6f522641217b..01b74815f52e691923d7a719e7c93e4a591102b7 100644 (file)
--- a/lib/Transforms/Scalar/IndVarSimplify.cpp
+++ b/lib/Transforms/Scalar/IndVarSimplify.cpp
@@ -68,7 +68,10 @@ namespace {
     ScalarEvolution *SE;
     bool Changed;
   public:
-    
+
+   static char ID; // Pass identification, replacement for typeid
+   IndVarSimplify() : LoopPass((intptr_t)&ID) {}
+
    bool runOnLoop(Loop *L, LPPassManager &LPM);
    bool doInitialization(Loop *L, LPPassManager &LPM);
    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
@@ -91,6 +94,8 @@ namespace {
 
     void DeleteTriviallyDeadInstructions(std::set<Instruction*> &Insts);
   };
+
+  char IndVarSimplify::ID = 0;
   RegisterPass<IndVarSimplify> X("indvars", "Canonicalize Induction Variables");
 }
 
@@ -110,7 +115,7 @@ DeleteTriviallyDeadInstructions(std::set<Instruction*> &Insts) {
       for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i)
         if (Instruction *U = dyn_cast<Instruction>(I->getOperand(i)))
           Insts.insert(U);
-      SE->deleteInstructionFromRecords(I);
+      SE->deleteValueFromRecords(I);
       DOUT << "INDVARS: Deleting: " << *I;
       I->eraseFromParent();
       Changed = true;
@@ -176,6 +181,7 @@ void IndVarSimplify::EliminatePointerRecurrence(PHINode *PN,
               GetElementPtrInst *NGEPI = new GetElementPtrInst(
                   NCE, Constant::getNullValue(Type::Int32Ty), NewAdd, 
                   GEPI->getName(), GEPI);
+              SE->deleteValueFromRecords(GEPI);
               GEPI->replaceAllUsesWith(NGEPI);
               GEPI->eraseFromParent();
               GEPI = NGEPI;
@@ -258,8 +264,8 @@ Instruction *IndVarSimplify::LinearFunctionTestReplace(Loop *L,
     // The IterationCount expression contains the number of times that the
     // backedge actually branches to the loop header.  This is one less than the
     // number of times the loop executes, so add one to it.
-    Constant *OneC = ConstantInt::get(IterationCount->getType(), 1);
-    TripCount = SCEVAddExpr::get(IterationCount, SCEVUnknown::get(OneC));
+    ConstantInt *OneC = ConstantInt::get(IterationCount->getType(), 1);
+    TripCount = SCEVAddExpr::get(IterationCount, SCEVConstant::get(OneC));
     IndVar = L->getCanonicalInductionVariableIncrement();
   } else {
     // We have to use the preincremented value...
@@ -271,8 +277,7 @@ Instruction *IndVarSimplify::LinearFunctionTestReplace(Loop *L,
 
   // Expand the code for the iteration count into the preheader of the loop.
   BasicBlock *Preheader = L->getLoopPreheader();
-  Value *ExitCnt = RW.expandCodeFor(TripCount, Preheader->getTerminator(),
-                                    IndVar->getType());
+  Value *ExitCnt = RW.expandCodeFor(TripCount, Preheader->getTerminator());
 
   // Insert a new icmp_ne or icmp_eq instruction before the branch.
   ICmpInst::Predicate Opcode;
@@ -377,7 +382,7 @@ void IndVarSimplify::RewriteLoopExitValues(Loop *L) {
         // just reuse it.
         Value *&ExitVal = ExitValues[Inst];
         if (!ExitVal)
-          ExitVal = Rewriter.expandCodeFor(ExitValue, InsertPt,Inst->getType());
+          ExitVal = Rewriter.expandCodeFor(ExitValue, InsertPt);
         
         DOUT << "INDVARS: RLEV: AfterLoopVal = " << *ExitVal
              << "  LoopVal = " << *Inst << "\n";
@@ -393,6 +398,7 @@ void IndVarSimplify::RewriteLoopExitValues(Loop *L) {
         // the PHI entirely.  This is safe, because the NewVal won't be variant
         // in the loop, so we don't need an LCSSA phi node anymore.
         if (NumPreds == 1) {
+          SE->deleteValueFromRecords(PN);
           PN->replaceAllUsesWith(ExitVal);
           PN->eraseFromParent();
           break;
@@ -512,9 +518,15 @@ bool IndVarSimplify::runOnLoop(Loop *L, LPPassManager &LPM) {
   Changed = true;
   DOUT << "INDVARS: New CanIV: " << *IndVar;
 
-  if (!isa<SCEVCouldNotCompute>(IterationCount))
+  if (!isa<SCEVCouldNotCompute>(IterationCount)) {
+    if (IterationCount->getType()->getPrimitiveSizeInBits() <
+        LargestType->getPrimitiveSizeInBits())
+      IterationCount = SCEVZeroExtendExpr::get(IterationCount, LargestType);
+    else if (IterationCount->getType() != LargestType)
+      IterationCount = SCEVTruncateExpr::get(IterationCount, LargestType);
     if (Instruction *DI = LinearFunctionTestReplace(L, IterationCount,Rewriter))
       DeadInsts.insert(DI);
+  }
 
   // Now that we have a canonical induction variable, we can rewrite any
   // recurrences in terms of the induction variable.  Start with the auxillary
@@ -548,8 +560,7 @@ bool IndVarSimplify::runOnLoop(Loop *L, LPPassManager &LPM) {
   std::map<unsigned, Value*> InsertedSizes;
   while (!IndVars.empty()) {
     PHINode *PN = IndVars.back().first;
-    Value *NewVal = Rewriter.expandCodeFor(IndVars.back().second, InsertPt,
-                                           PN->getType());
+    Value *NewVal = Rewriter.expandCodeFor(IndVars.back().second, InsertPt);
     DOUT << "INDVARS: Rewrote IV '" << *IndVars.back().second << "' " << *PN
          << "   into = " << *NewVal << "\n";
     NewVal->takeName(PN);