1 files changed, 32 insertions, 41 deletions

diff --git a/lib/Transforms/InstCombine/InstCombineAddSub.cpp b/lib/Transforms/InstCombine/InstCombineAddSub.cpp
index 4891ff0..2da17f1 100644
--- a/lib/Transforms/InstCombine/InstCombineAddSub.cpp
+++ b/lib/Transforms/InstCombine/InstCombineAddSub.cpp
@@ -35,7 +35,7 @@ static Constant *SubOne(ConstantInt *C) {
 // Otherwise, return null.
 //
 static inline Value *dyn_castFoldableMul(Value *V, ConstantInt *&CST) {
-  if (!V->hasOneUse() || !V->getType()->isInteger())
+  if (!V->hasOneUse() || !V->getType()->isIntegerTy())
     return 0;
   
   Instruction *I = dyn_cast<Instruction>(V);
@@ -121,50 +121,34 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
         match(LHS, m_Xor(m_Value(XorLHS), m_ConstantInt(XorRHS)))) {
       uint32_t TySizeBits = I.getType()->getScalarSizeInBits();
       const APInt& RHSVal = cast<ConstantInt>(RHSC)->getValue();
-      
-      uint32_t Size = TySizeBits / 2;
-      APInt C0080Val(APInt(TySizeBits, 1ULL).shl(Size - 1));
-      APInt CFF80Val(-C0080Val);
-      do {
-        if (TySizeBits > Size) {
-          // If we have ADD(XOR(AND(X, 0xFF), 0x80), 0xF..F80), it's a sext.
-          // If we have ADD(XOR(AND(X, 0xFF), 0xF..F80), 0x80), it's a sext.
-          if ((RHSVal == CFF80Val && XorRHS->getValue() == C0080Val) ||
-              (RHSVal == C0080Val && XorRHS->getValue() == CFF80Val)) {
-            // This is a sign extend if the top bits are known zero.
-            if (!MaskedValueIsZero(XorLHS, 
-                   APInt::getHighBitsSet(TySizeBits, TySizeBits - Size)))
-              Size = 0;  // Not a sign ext, but can't be any others either.
-            break;
-          }
-        }
-        Size >>= 1;
-        C0080Val = APIntOps::lshr(C0080Val, Size);
-        CFF80Val = APIntOps::ashr(CFF80Val, Size);
-      } while (Size >= 1);
-      
-      // FIXME: This shouldn't be necessary. When the backends can handle types
-      // with funny bit widths then this switch statement should be removed. It
-      // is just here to get the size of the "middle" type back up to something
-      // that the back ends can handle.
-      const Type *MiddleType = 0;
-      switch (Size) {
-        default: break;
-        case 32:
-        case 16:
-        case  8: MiddleType = IntegerType::get(I.getContext(), Size); break;
+      unsigned ExtendAmt = 0;
+      // If we have ADD(XOR(AND(X, 0xFF), 0x80), 0xF..F80), it's a sext.
+      // If we have ADD(XOR(AND(X, 0xFF), 0xF..F80), 0x80), it's a sext.
+      if (XorRHS->getValue() == -RHSVal) {
+        if (RHSVal.isPowerOf2())
+          ExtendAmt = TySizeBits - RHSVal.logBase2() - 1;
+        else if (XorRHS->getValue().isPowerOf2())
+          ExtendAmt = TySizeBits - XorRHS->getValue().logBase2() - 1;
+      }
+
+      if (ExtendAmt) {
+        APInt Mask = APInt::getHighBitsSet(TySizeBits, ExtendAmt);
+        if (!MaskedValueIsZero(XorLHS, Mask))
+          ExtendAmt = 0;
       }
-      if (MiddleType) {
-        Value *NewTrunc = Builder->CreateTrunc(XorLHS, MiddleType, "sext");
-        return new SExtInst(NewTrunc, I.getType(), I.getName());
+
+      if (ExtendAmt) {
+        Constant *ShAmt = ConstantInt::get(I.getType(), ExtendAmt);
+        Value *NewShl = Builder->CreateShl(XorLHS, ShAmt, "sext");
+        return BinaryOperator::CreateAShr(NewShl, ShAmt);
       }
     }
   }
 
-  if (I.getType()->isInteger(1))
+  if (I.getType()->isIntegerTy(1))
     return BinaryOperator::CreateXor(LHS, RHS);
 
-  if (I.getType()->isInteger()) {
+  if (I.getType()->isIntegerTy()) {
     // X + X --> X << 1
     if (LHS == RHS)
       return BinaryOperator::CreateShl(LHS, ConstantInt::get(I.getType(), 1));
@@ -184,7 +168,7 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
   // -A + B  -->  B - A
   // -A + -B  -->  -(A + B)
   if (Value *LHSV = dyn_castNegVal(LHS)) {
-    if (LHS->getType()->isIntOrIntVector()) {
+    if (LHS->getType()->isIntOrIntVectorTy()) {
       if (Value *RHSV = dyn_castNegVal(RHS)) {
         Value *NewAdd = Builder->CreateAdd(LHSV, RHSV, "sum");
         return BinaryOperator::CreateNeg(NewAdd);
@@ -238,7 +222,7 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
   }
 
   // W*X + Y*Z --> W * (X+Z)  iff W == Y
-  if (I.getType()->isIntOrIntVector()) {
+  if (I.getType()->isIntOrIntVectorTy()) {
     Value *W, *X, *Y, *Z;
     if (match(LHS, m_Mul(m_Value(W), m_Value(X))) &&
         match(RHS, m_Mul(m_Value(Y), m_Value(Z)))) {
@@ -576,7 +560,7 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
     return ReplaceInstUsesWith(I, Op0);    // undef - X -> undef
   if (isa<UndefValue>(Op1))
     return ReplaceInstUsesWith(I, Op1);    // X - undef -> undef
-  if (I.getType()->isInteger(1))
+  if (I.getType()->isIntegerTy(1))
     return BinaryOperator::CreateXor(Op0, Op1);
   
   if (ConstantInt *C = dyn_cast<ConstantInt>(Op0)) {
@@ -676,6 +660,13 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
               return BinaryOperator::CreateSDiv(Op1I->getOperand(0),
                                           ConstantExpr::getNeg(DivRHS));
 
+      // 0 - (C << X)  -> (-C << X)
+      if (Op1I->getOpcode() == Instruction::Shl)
+        if (ConstantInt *CSI = dyn_cast<ConstantInt>(Op0))
+          if (CSI->isZero())
+            if (Value *ShlLHSNeg = dyn_castNegVal(Op1I->getOperand(0)))
+              return BinaryOperator::CreateShl(ShlLHSNeg, Op1I->getOperand(1));
+
       // X - X*C --> X * (1-C)
       ConstantInt *C2 = 0;
       if (dyn_castFoldableMul(Op1I, C2) == Op0) {