Revert r146822 at Pete Cooper's request as it broke clang self hosting.

[oota-llvm.git] / lib / Transforms / Utils / SimplifyIndVar.cpp

diff --git a/lib/Transforms/Utils/SimplifyIndVar.cpp b/lib/Transforms/Utils/SimplifyIndVar.cpp
index ffaad2717b4054d06b9c270b63c2c96d36a1d443..6732a789d5f1a93c9f047b161feee58b82eff277 100644 (file)
--- a/lib/Transforms/Utils/SimplifyIndVar.cpp
+++ b/lib/Transforms/Utils/SimplifyIndVar.cpp
@@ -85,6 +85,8 @@ namespace {
 /// foldIVUser - Fold an IV operand into its use.  This removes increments of an
 /// aligned IV when used by a instruction that ignores the low bits.
 ///
+/// IVOperand is guaranteed SCEVable, but UseInst may not be.
+///
 /// Return the operand of IVOperand for this induction variable if IVOperand can
 /// be folded (in case more folding opportunities have been exposed).
 /// Otherwise return null.
@@ -105,8 +107,8 @@ Value *SimplifyIndvar::foldIVUser(Instruction *UseInst, Instruction *IVOperand)
 
     // Attempt to fold a binary operator with constant operand.
     // e.g. ((I + 1) >> 2) => I >> 2
-    if (IVOperand->getNumOperands() != 2 ||
-        !isa<ConstantInt>(IVOperand->getOperand(1)))
+    if (!isa<BinaryOperator>(IVOperand)
+        || !isa<ConstantInt>(IVOperand->getOperand(1)))
       return 0;
 
     IVSrc = IVOperand->getOperand(0);
@@ -219,8 +221,7 @@ void SimplifyIndvar::eliminateIVRemainder(BinaryOperator *Rem,
       return;
 
     ICmpInst *ICmp = new ICmpInst(Rem, ICmpInst::ICMP_EQ,
-                                  Rem->getOperand(0), Rem->getOperand(1),
-                                  "tmp");
+                                  Rem->getOperand(0), Rem->getOperand(1));
     SelectInst *Sel =
       SelectInst::Create(ICmp,
                          ConstantInt::get(Rem->getType(), 0),
@@ -241,6 +242,7 @@ void SimplifyIndvar::eliminateIVRemainder(BinaryOperator *Rem,
 
 /// eliminateIVUser - Eliminate an operation that consumes a simple IV and has
 /// no observable side-effect given the range of IV values.
+/// IVOperand is guaranteed SCEVable, but UseInst may not be.
 bool SimplifyIndvar::eliminateIVUser(Instruction *UseInst,
                                      Instruction *IVOperand) {
   if (ICmpInst *ICmp = dyn_cast<ICmpInst>(UseInst)) {
@@ -324,6 +326,9 @@ static bool isSimpleIVUser(Instruction *I, const Loop *L, ScalarEvolution *SE) {
 /// Once DisableIVRewrite is default, LSR will be the only client of IVUsers.
 ///
 void SimplifyIndvar::simplifyUsers(PHINode *CurrIV, IVVisitor *V) {
+  if (!SE->isSCEVable(CurrIV->getType()))
+    return;
+
   // Instructions processed by SimplifyIndvar for CurrIV.
   SmallPtrSet<Instruction*,16> Simplified;