Don't use a potentially expensive shift if all we want is one set bit.

No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186095 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index af5051650ee2274143ad0451ff019f03dee5b8b2..1d5e5fb71954c166c439ea22c478fd4f2076651b 100644 (file)
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -758,7 +758,7 @@ static const SCEV *BinomialCoefficient(const SCEV *It, unsigned K,
   unsigned CalculationBits = W + T;
 
   // Calculate 2^T, at width T+W.
-  APInt DivFactor = APInt(CalculationBits, 1).shl(T);
+  APInt DivFactor = APInt::getOneBitSet(CalculationBits, T);
 
   // Calculate the multiplicative inverse of K! / 2^T;
   // this multiplication factor will perform the exact division by
@@ -3789,7 +3789,7 @@ const SCEV *ScalarEvolution::createSCEV(Value *V) {
         break;
 
       Constant *X = ConstantInt::get(getContext(),
-        APInt(BitWidth, 1).shl(SA->getZExtValue()));
+        APInt::getOneBitSet(BitWidth, SA->getZExtValue()));
       return getMulExpr(getSCEV(U->getOperand(0)), getSCEV(X));
     }
     break;
@@ -3807,7 +3807,7 @@ const SCEV *ScalarEvolution::createSCEV(Value *V) {
         break;
 
       Constant *X = ConstantInt::get(getContext(),
-        APInt(BitWidth, 1).shl(SA->getZExtValue()));
+        APInt::getOneBitSet(BitWidth, SA->getZExtValue()));
       return getUDivExpr(getSCEV(U->getOperand(0)), getSCEV(X));
     }
     break;

diff --git a/lib/Support/ConstantRange.cpp b/lib/Support/ConstantRange.cpp
index d770381dcd5a3f784a4dadc8fdde3f5f4adffb71..bb38cd15e634144b987ba461e94e7c6338445fea 100644 (file)
--- a/lib/Support/ConstantRange.cpp
+++ b/lib/Support/ConstantRange.cpp
@@ -433,7 +433,7 @@ ConstantRange ConstantRange::zeroExtend(uint32_t DstTySize) const {
     APInt LowerExt(DstTySize, 0);
     if (!Upper) // special case: [X, 0) -- not really wrapping around
       LowerExt = Lower.zext(DstTySize);
-    return ConstantRange(LowerExt, APInt(DstTySize, 1).shl(SrcTySize));
+    return ConstantRange(LowerExt, APInt::getOneBitSet(DstTySize, SrcTySize));
   }
 
   return ConstantRange(Lower.zext(DstTySize), Upper.zext(DstTySize));

diff --git a/lib/Transforms/InstCombine/InstCombineAddSub.cpp b/lib/Transforms/InstCombine/InstCombineAddSub.cpp
index ac7eac94c9d3c3cd4767d47d08487f11f52299e1..03fd35fb8171a2448ac0cb40ef4e2a2673045dd5 100644 (file)
--- a/lib/Transforms/InstCombine/InstCombineAddSub.cpp
+++ b/lib/Transforms/InstCombine/InstCombineAddSub.cpp
@@ -876,7 +876,7 @@ static inline Value *dyn_castFoldableMul(Value *V, ConstantInt *&CST) {
       uint32_t BitWidth = cast<IntegerType>(V->getType())->getBitWidth();
       uint32_t CSTVal = CST->getLimitedValue(BitWidth);
       CST = ConstantInt::get(V->getType()->getContext(),
-                             APInt(BitWidth, 1).shl(CSTVal));
+                             APInt::getOneBitSet(BitWidth, CSTVal));
       return I->getOperand(0);
     }
   return 0;

diff --git a/lib/Transforms/Utils/SimplifyIndVar.cpp b/lib/Transforms/Utils/SimplifyIndVar.cpp
index 41c207c3d5cb9c428fd93269ac995b647b3a2998..bf3442aeaaad16d7121abce2d1173bc5772ab2f1 100644 (file)
--- a/lib/Transforms/Utils/SimplifyIndVar.cpp
+++ b/lib/Transforms/Utils/SimplifyIndVar.cpp
@@ -119,7 +119,7 @@ Value *SimplifyIndvar::foldIVUser(Instruction *UseInst, Instruction *IVOperand)
         return 0;
 
       D = ConstantInt::get(UseInst->getContext(),
-                           APInt(BitWidth, 1).shl(D->getZExtValue()));
+                           APInt::getOneBitSet(BitWidth, D->getZExtValue()));
     }
     FoldedExpr = SE->getUDivExpr(SE->getSCEV(IVSrc), SE->getSCEV(D));
   }