[llvm] r298204 - [InstCombine] Use setHighBits/setLowBits/setBitsFrom in place of getLowBitsSet/getHighBitsSet.

Craig Topper via llvm-commits llvm-commits at lists.llvm.org
Sat Mar 18 22:49:16 PDT 2017


Author: ctopper
Date: Sun Mar 19 00:49:16 2017
New Revision: 298204

URL: http://llvm.org/viewvc/llvm-project?rev=298204&view=rev
Log:
[InstCombine] Use setHighBits/setLowBits/setBitsFrom in place of getLowBitsSet/getHighBitsSet.

Modified:
    llvm/trunk/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp

Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp?rev=298204&r1=298203&r2=298204&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp Sun Mar 19 00:49:16 2017
@@ -483,7 +483,7 @@ Value *InstCombiner::SimplifyDemandedUse
     KnownOne = KnownOne.zext(BitWidth);
     assert(!(KnownZero & KnownOne) && "Bits known to be one AND zero?");
     // The top bits are known to be zero.
-    KnownZero |= APInt::getHighBitsSet(BitWidth, BitWidth - SrcBitWidth);
+    KnownZero.setBitsFrom(SrcBitWidth);
     break;
   }
   case Instruction::SExt: {
@@ -493,7 +493,7 @@ Value *InstCombiner::SimplifyDemandedUse
     APInt InputDemandedBits = DemandedMask &
                               APInt::getLowBitsSet(BitWidth, SrcBitWidth);
 
-    APInt NewBits(APInt::getHighBitsSet(BitWidth, BitWidth - SrcBitWidth));
+    APInt NewBits(APInt::getBitsSetFrom(BitWidth, SrcBitWidth));
     // If any of the sign extended bits are demanded, we know that the sign
     // bit is demanded.
     if ((NewBits & DemandedMask) != 0)
@@ -572,9 +572,9 @@ Value *InstCombiner::SimplifyDemandedUse
       // If the shift is NUW/NSW, then it does demand the high bits.
       ShlOperator *IOp = cast<ShlOperator>(I);
       if (IOp->hasNoSignedWrap())
-        DemandedMaskIn |= APInt::getHighBitsSet(BitWidth, ShiftAmt+1);
+        DemandedMaskIn.setHighBits(ShiftAmt+1);
       else if (IOp->hasNoUnsignedWrap())
-        DemandedMaskIn |= APInt::getHighBitsSet(BitWidth, ShiftAmt);
+        DemandedMaskIn.setHighBits(ShiftAmt);
 
       if (SimplifyDemandedBits(I->getOperandUse(0), DemandedMaskIn, KnownZero,
                                KnownOne, Depth + 1))
@@ -584,7 +584,7 @@ Value *InstCombiner::SimplifyDemandedUse
       KnownOne  <<= ShiftAmt;
       // low bits known zero.
       if (ShiftAmt)
-        KnownZero |= APInt::getLowBitsSet(BitWidth, ShiftAmt);
+        KnownZero.setLowBits(ShiftAmt);
     }
     break;
   case Instruction::LShr:
@@ -598,7 +598,7 @@ Value *InstCombiner::SimplifyDemandedUse
       // If the shift is exact, then it does demand the low bits (and knows that
       // they are zero).
       if (cast<LShrOperator>(I)->isExact())
-        DemandedMaskIn |= APInt::getLowBitsSet(BitWidth, ShiftAmt);
+        DemandedMaskIn.setLowBits(ShiftAmt);
 
       if (SimplifyDemandedBits(I->getOperandUse(0), DemandedMaskIn, KnownZero,
                                KnownOne, Depth + 1))
@@ -606,11 +606,8 @@ Value *InstCombiner::SimplifyDemandedUse
       assert(!(KnownZero & KnownOne) && "Bits known to be one AND zero?");
       KnownZero = APIntOps::lshr(KnownZero, ShiftAmt);
       KnownOne  = APIntOps::lshr(KnownOne, ShiftAmt);
-      if (ShiftAmt) {
-        // Compute the new bits that are at the top now.
-        APInt HighBits(APInt::getHighBitsSet(BitWidth, ShiftAmt));
-        KnownZero |= HighBits;  // high bits known zero.
-      }
+      if (ShiftAmt)
+        KnownZero.setHighBits(ShiftAmt);  // high bits known zero.
     }
     break;
   case Instruction::AShr:
@@ -643,7 +640,7 @@ Value *InstCombiner::SimplifyDemandedUse
       // If the shift is exact, then it does demand the low bits (and knows that
       // they are zero).
       if (cast<AShrOperator>(I)->isExact())
-        DemandedMaskIn |= APInt::getLowBitsSet(BitWidth, ShiftAmt);
+        DemandedMaskIn.setLowBits(ShiftAmt);
 
       if (SimplifyDemandedBits(I->getOperandUse(0), DemandedMaskIn, KnownZero,
                                KnownOne, Depth + 1))
@@ -716,7 +713,7 @@ Value *InstCombiner::SimplifyDemandedUse
                        CxtI);
       // If it's known zero, our sign bit is also zero.
       if (LHSKnownZero.isNegative())
-        KnownZero.setBit(KnownZero.getBitWidth() - 1);
+        KnownZero.setSignBit();
     }
     break;
   case Instruction::URem: {
@@ -795,11 +792,11 @@ Value *InstCombiner::SimplifyDemandedUse
           return ConstantInt::getNullValue(VTy);
 
         // We know that the upper bits are set to zero.
-        KnownZero = APInt::getHighBitsSet(BitWidth, BitWidth - ArgWidth);
+        KnownZero.setBitsFrom(ArgWidth);
         return nullptr;
       }
       case Intrinsic::x86_sse42_crc32_64_64:
-        KnownZero = APInt::getHighBitsSet(64, 32);
+        KnownZero.setBitsFrom(32);
         return nullptr;
       }
     }
@@ -852,7 +849,7 @@ Value *InstCombiner::SimplifyShrShlDeman
   unsigned ShrAmt = ShrOp1.getZExtValue();
 
   KnownOne.clearAllBits();
-  KnownZero = APInt::getLowBitsSet(KnownZero.getBitWidth(), ShlAmt - 1);
+  KnownZero.setLowBits(ShlAmt - 1);
   KnownZero &= DemandedMask;
 
   APInt BitMask1(APInt::getAllOnesValue(BitWidth));
@@ -1559,7 +1556,7 @@ Value *InstCombiner::SimplifyDemandedVec
     case Intrinsic::x86_sse4a_extrqi:
     case Intrinsic::x86_sse4a_insertq:
     case Intrinsic::x86_sse4a_insertqi:
-      UndefElts |= APInt::getHighBitsSet(VWidth, VWidth / 2);
+      UndefElts.setHighBits(VWidth / 2);
       break;
     case Intrinsic::amdgcn_buffer_load:
     case Intrinsic::amdgcn_buffer_load_format: {




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