PR5207: Change APInt methods trunc(), sext(), zext(), sextOrTrunc() and

zextOrTrunc(), and APSInt methods extend(), extOrTrunc() and new method
trunc(), to be const and to return a new value instead of modifying the
object in place.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121120 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 28 insertions, 31 deletions

diff --git a/lib/Transforms/InstCombine/InstCombineCompares.cpp b/lib/Transforms/InstCombine/InstCombineCompares.cpp
index 6efff32416..d2841af8bc 100644
--- a/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -939,8 +939,7 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI,
       // If all the high bits are known, we can do this xform.
       if ((KnownZero|KnownOne).countLeadingOnes() >= SrcBits-DstBits) {
         // Pull in the high bits from known-ones set.
-        APInt NewRHS(RHS->getValue());
-        NewRHS.zext(SrcBits);
+        APInt NewRHS = RHS->getValue().zext(SrcBits);
         NewRHS |= KnownOne;
         return new ICmpInst(ICI.getPredicate(), LHSI->getOperand(0),
                             ConstantInt::get(ICI.getContext(), NewRHS));
@@ -1022,10 +1021,8 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI,
              (AndCST->getValue().isNonNegative() && RHSV.isNonNegative()))) {
           uint32_t BitWidth = 
             cast<IntegerType>(Cast->getOperand(0)->getType())->getBitWidth();
-          APInt NewCST = AndCST->getValue();
-          NewCST.zext(BitWidth);
-          APInt NewCI = RHSV;
-          NewCI.zext(BitWidth);
+          APInt NewCST = AndCST->getValue().zext(BitWidth);
+          APInt NewCI = RHSV.zext(BitWidth);
           Value *NewAnd = 
             Builder->CreateAnd(Cast->getOperand(0),
                            ConstantInt::get(ICI.getContext(), NewCST),
diff --git a/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp b/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
index 1433f7bbc9..6bce6a2ed1 100644
--- a/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
+++ b/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
@@ -29,11 +29,11 @@ static bool MultiplyOverflows(ConstantInt *C1, ConstantInt *C2, bool sign) {
   uint32_t W = C1->getBitWidth();
   APInt LHSExt = C1->getValue(), RHSExt = C2->getValue();
   if (sign) {
-    LHSExt.sext(W * 2);
-    RHSExt.sext(W * 2);
+    LHSExt = LHSExt.sext(W * 2);
+    RHSExt = RHSExt.sext(W * 2);
   } else {
-    LHSExt.zext(W * 2);
-    RHSExt.zext(W * 2);
+    LHSExt = LHSExt.zext(W * 2);
+    RHSExt = RHSExt.zext(W * 2);
   }
   
   APInt MulExt = LHSExt * RHSExt;
diff --git a/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp b/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp
index 5366bdd0c3..48184c0bd2 100644
--- a/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp
+++ b/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp
@@ -34,7 +34,7 @@ static bool ShrinkDemandedConstant(Instruction *I, unsigned OpNo,
   if (!OpC) return false;
 
   // If there are no bits set that aren't demanded, nothing to do.
-  Demanded.zextOrTrunc(OpC->getValue().getBitWidth());
+  Demanded = Demanded.zextOrTrunc(OpC->getValue().getBitWidth());
   if ((~Demanded & OpC->getValue()) == 0)
     return false;
 
@@ -388,15 +388,15 @@ Value *InstCombiner::SimplifyDemandedUseBits(Value *V, APInt DemandedMask,
     break;
   case Instruction::Trunc: {
     unsigned truncBf = I->getOperand(0)->getType()->getScalarSizeInBits();
-    DemandedMask.zext(truncBf);
-    KnownZero.zext(truncBf);
-    KnownOne.zext(truncBf);
+    DemandedMask = DemandedMask.zext(truncBf);
+    KnownZero = KnownZero.zext(truncBf);
+    KnownOne = KnownOne.zext(truncBf);
     if (SimplifyDemandedBits(I->getOperandUse(0), DemandedMask, 
                              KnownZero, KnownOne, Depth+1))
       return I;
-    DemandedMask.trunc(BitWidth);
-    KnownZero.trunc(BitWidth);
-    KnownOne.trunc(BitWidth);
+    DemandedMask = DemandedMask.trunc(BitWidth);
+    KnownZero = KnownZero.trunc(BitWidth);
+    KnownOne = KnownOne.trunc(BitWidth);
     assert(!(KnownZero & KnownOne) && "Bits known to be one AND zero?"); 
     break;
   }
@@ -426,15 +426,15 @@ Value *InstCombiner::SimplifyDemandedUseBits(Value *V, APInt DemandedMask,
     // Compute the bits in the result that are not present in the input.
     unsigned SrcBitWidth =I->getOperand(0)->getType()->getScalarSizeInBits();
     
-    DemandedMask.trunc(SrcBitWidth);
-    KnownZero.trunc(SrcBitWidth);
-    KnownOne.trunc(SrcBitWidth);
+    DemandedMask = DemandedMask.trunc(SrcBitWidth);
+    KnownZero = KnownZero.trunc(SrcBitWidth);
+    KnownOne = KnownOne.trunc(SrcBitWidth);
     if (SimplifyDemandedBits(I->getOperandUse(0), DemandedMask,
                              KnownZero, KnownOne, Depth+1))
       return I;
-    DemandedMask.zext(BitWidth);
-    KnownZero.zext(BitWidth);
-    KnownOne.zext(BitWidth);
+    DemandedMask = DemandedMask.zext(BitWidth);
+    KnownZero = KnownZero.zext(BitWidth);
+    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);
@@ -453,15 +453,15 @@ Value *InstCombiner::SimplifyDemandedUseBits(Value *V, APInt DemandedMask,
     if ((NewBits & DemandedMask) != 0)
       InputDemandedBits.setBit(SrcBitWidth-1);
       
-    InputDemandedBits.trunc(SrcBitWidth);
-    KnownZero.trunc(SrcBitWidth);
-    KnownOne.trunc(SrcBitWidth);
+    InputDemandedBits = InputDemandedBits.trunc(SrcBitWidth);
+    KnownZero = KnownZero.trunc(SrcBitWidth);
+    KnownOne = KnownOne.trunc(SrcBitWidth);
     if (SimplifyDemandedBits(I->getOperandUse(0), InputDemandedBits,
                              KnownZero, KnownOne, Depth+1))
       return I;
-    InputDemandedBits.zext(BitWidth);
-    KnownZero.zext(BitWidth);
-    KnownOne.zext(BitWidth);
+    InputDemandedBits = InputDemandedBits.zext(BitWidth);
+    KnownZero = KnownZero.zext(BitWidth);
+    KnownOne = KnownOne.zext(BitWidth);
     assert(!(KnownZero & KnownOne) && "Bits known to be one AND zero?"); 
       
     // If the sign bit of the input is known set or clear, then we know the
diff --git a/lib/Transforms/Scalar/MemCpyOptimizer.cpp b/lib/Transforms/Scalar/MemCpyOptimizer.cpp
index 5d867e7154..318e212899 100644
--- a/lib/Transforms/Scalar/MemCpyOptimizer.cpp
+++ b/lib/Transforms/Scalar/MemCpyOptimizer.cpp
@@ -63,8 +63,8 @@ static Value *isBytewiseValue(Value *V) {
       while (Val.getBitWidth() != 8) {
         unsigned NextWidth = Val.getBitWidth()/2;
         Val2  = Val.lshr(NextWidth);
-        Val2.trunc(Val.getBitWidth()/2);
-        Val.trunc(Val.getBitWidth()/2);
+        Val2 = Val2.trunc(Val.getBitWidth()/2);
+        Val = Val.trunc(Val.getBitWidth()/2);
 
         // If the top/bottom halves aren't the same, reject it.
         if (Val != Val2)