[ValueTracking] Convert most of the calls to computeKnownBits to use …

…the version that returns the KnownBits object.

This continues the changes started when computeSignBit was replaced with this new version of computeKnowBits.

Differential Revision: https://reviews.llvm.org/D33431

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303773 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Analysis/ConstantFolding.cpp

@@ -687,11 +687,8 @@ Constant *SymbolicallyEvaluateBinop(unsigned Opc, Constant *Op0, Constant *Op1,
   // bits.
 
   if (Opc == Instruction::And) {
-    unsigned BitWidth = DL.getTypeSizeInBits(Op0->getType()->getScalarType());
-    KnownBits Known0(BitWidth);
-    KnownBits Known1(BitWidth);
-    computeKnownBits(Op0, Known0, DL);
-    computeKnownBits(Op1, Known1, DL);
+    KnownBits Known0 = computeKnownBits(Op0, DL);
+    KnownBits Known1 = computeKnownBits(Op1, DL);
     if ((Known1.One | Known0.Zero).isAllOnesValue()) {
       // All the bits of Op0 that the 'and' could be masking are already zero.
       return Op0;

lib/Analysis/InstructionSimplify.cpp

@@ -688,9 +688,7 @@ static Value *SimplifySubInst(Value *Op0, Value *Op1, bool isNSW, bool isNUW,
     if (isNUW)
       return Op0;
 
-    unsigned BitWidth = Op1->getType()->getScalarSizeInBits();
-    KnownBits Known(BitWidth);
-    computeKnownBits(Op1, Known, Q.DL, 0, Q.AC, Q.CxtI, Q.DT);
+    KnownBits Known = computeKnownBits(Op1, Q.DL, 0, Q.AC, Q.CxtI, Q.DT);
     if (Known.Zero.isMaxSignedValue()) {
       // Op1 is either 0 or the minimum signed value. If the sub is NSW, then
       // Op1 must be 0 because negating the minimum signed value is undefined.
@@ -1309,15 +1307,13 @@ static Value *SimplifyShift(Instruction::BinaryOps Opcode, Value *Op0,
 
   // If any bits in the shift amount make that value greater than or equal to
   // the number of bits in the type, the shift is undefined.
-  unsigned BitWidth = Op1->getType()->getScalarSizeInBits();
-  KnownBits Known(BitWidth);
-  computeKnownBits(Op1, Known, Q.DL, 0, Q.AC, Q.CxtI, Q.DT);
-  if (Known.One.getLimitedValue() >= BitWidth)
+  KnownBits Known = computeKnownBits(Op1, Q.DL, 0, Q.AC, Q.CxtI, Q.DT);
+  if (Known.One.getLimitedValue() >= Known.getBitWidth())
     return UndefValue::get(Op0->getType());
 
   // If all valid bits in the shift amount are known zero, the first operand is
   // unchanged.
-  unsigned NumValidShiftBits = Log2_32_Ceil(BitWidth);
+  unsigned NumValidShiftBits = Log2_32_Ceil(Known.getBitWidth());
   if (Known.countMinTrailingZeros() >= NumValidShiftBits)
     return Op0;
 
@@ -1343,9 +1339,7 @@ static Value *SimplifyRightShift(Instruction::BinaryOps Opcode, Value *Op0,
 
   // The low bit cannot be shifted out of an exact shift if it is set.
   if (isExact) {
-    unsigned BitWidth = Op0->getType()->getScalarSizeInBits();
-    KnownBits Op0Known(BitWidth);
-    computeKnownBits(Op0, Op0Known, Q.DL, /*Depth=*/0, Q.AC, Q.CxtI, Q.DT);
+    KnownBits Op0Known = computeKnownBits(Op0, Q.DL, /*Depth=*/0, Q.AC, Q.CxtI, Q.DT);
     if (Op0Known.One[0])
       return Op0;
   }
@@ -3372,9 +3366,7 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS,
   if (ICmpInst::isEquality(Pred)) {
     const APInt *RHSVal;
     if (match(RHS, m_APInt(RHSVal))) {
-      unsigned BitWidth = RHSVal->getBitWidth();
-      KnownBits LHSKnown(BitWidth);
-      computeKnownBits(LHS, LHSKnown, Q.DL, /*Depth=*/0, Q.AC, Q.CxtI, Q.DT);
+      KnownBits LHSKnown = computeKnownBits(LHS, Q.DL, /*Depth=*/0, Q.AC, Q.CxtI, Q.DT);
       if (LHSKnown.Zero.intersects(*RHSVal) ||
           !LHSKnown.One.isSubsetOf(*RHSVal))
         return Pred == ICmpInst::ICMP_EQ ? ConstantInt::getFalse(ITy)
@@ -4684,9 +4676,7 @@ Value *llvm::SimplifyInstruction(Instruction *I, const SimplifyQuery &SQ,
   // In general, it is possible for computeKnownBits to determine all bits in a
   // value even when the operands are not all constants.
   if (!Result && I->getType()->isIntOrIntVectorTy()) {
-    unsigned BitWidth = I->getType()->getScalarSizeInBits();
-    KnownBits Known(BitWidth);
-    computeKnownBits(I, Known, Q.DL, /*Depth*/ 0, Q.AC, I, Q.DT, ORE);
+    KnownBits Known = computeKnownBits(I, Q.DL, /*Depth*/ 0, Q.AC, I, Q.DT, ORE);
     if (Known.isConstant())
       Result = ConstantInt::get(I->getType(), Known.getConstant());
   }

lib/Analysis/Lint.cpp

@@ -534,9 +534,7 @@ static bool isZero(Value *V, const DataLayout &DL, DominatorTree *DT,
 
   VectorType *VecTy = dyn_cast<VectorType>(V->getType());
   if (!VecTy) {
-    unsigned BitWidth = V->getType()->getIntegerBitWidth();
-    KnownBits Known(BitWidth);
-    computeKnownBits(V, Known, DL, 0, AC, dyn_cast<Instruction>(V), DT);
+    KnownBits Known = computeKnownBits(V, DL, 0, AC, dyn_cast<Instruction>(V), DT);
     return Known.isZero();
   }
 
@@ -550,14 +548,12 @@ static bool isZero(Value *V, const DataLayout &DL, DominatorTree *DT,
 
   // For a vector, KnownZero will only be true if all values are zero, so check
   // this per component
-  unsigned BitWidth = VecTy->getElementType()->getIntegerBitWidth();
   for (unsigned I = 0, N = VecTy->getNumElements(); I != N; ++I) {
     Constant *Elem = C->getAggregateElement(I);
     if (isa<UndefValue>(Elem))
       return true;
 
-    KnownBits Known(BitWidth);
-    computeKnownBits(Elem, Known, DL);
+    KnownBits Known = computeKnownBits(Elem, DL);
     if (Known.isZero())
       return true;
   }

lib/Analysis/ScalarEvolution.cpp

@@ -4648,10 +4648,7 @@ uint32_t ScalarEvolution::GetMinTrailingZerosImpl(const SCEV *S) {
 
   if (const SCEVUnknown *U = dyn_cast<SCEVUnknown>(S)) {
     // For a SCEVUnknown, ask ValueTracking.
-    unsigned BitWidth = getTypeSizeInBits(U->getType());
-    KnownBits Known(BitWidth);
-    computeKnownBits(U->getValue(), Known, getDataLayout(), 0, &AC,
-                     nullptr, &DT);
+    KnownBits Known = computeKnownBits(U->getValue(), getDataLayout(), 0, &AC, nullptr, &DT);
     return Known.countMinTrailingZeros();
   }
 
@@ -4831,8 +4828,7 @@ ScalarEvolution::getRange(const SCEV *S,
     const DataLayout &DL = getDataLayout();
     if (SignHint == ScalarEvolution::HINT_RANGE_UNSIGNED) {
       // For a SCEVUnknown, ask ValueTracking.
-      KnownBits Known(BitWidth);
-      computeKnownBits(U->getValue(), Known, DL, 0, &AC, nullptr, &DT);
+      KnownBits Known = computeKnownBits(U->getValue(), DL, 0, &AC, nullptr, &DT);
       if (Known.One != ~Known.Zero + 1)
         ConservativeResult =
             ConservativeResult.intersectWith(ConstantRange(Known.One,

lib/Transforms/InstCombine/InstCombineAddSub.cpp

@@ -861,12 +861,9 @@ bool InstCombiner::willNotOverflowSignedSub(const Value *LHS,
       ComputeNumSignBits(RHS, 0, &CxtI) > 1)
     return true;
 
-  unsigned BitWidth = LHS->getType()->getScalarSizeInBits();
-  KnownBits LHSKnown(BitWidth);
-  computeKnownBits(LHS, LHSKnown, 0, &CxtI);
+  KnownBits LHSKnown = computeKnownBits(LHS, 0, &CxtI);
 
-  KnownBits RHSKnown(BitWidth);
-  computeKnownBits(RHS, RHSKnown, 0, &CxtI);
+  KnownBits RHSKnown = computeKnownBits(RHS, 0, &CxtI);
 
   // Subtraction of two 2's complement numbers having identical signs will
   // never overflow.
@@ -1059,9 +1056,7 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
       // If this is a xor that was canonicalized from a sub, turn it back into
       // a sub and fuse this add with it.
       if (LHS->hasOneUse() && (XorRHS->getValue()+1).isPowerOf2()) {
-        IntegerType *IT = cast<IntegerType>(I.getType());
-        KnownBits LHSKnown(IT->getBitWidth());
-        computeKnownBits(XorLHS, LHSKnown, 0, &I);
+        KnownBits LHSKnown = computeKnownBits(XorLHS, 0, &I);
         if ((XorRHS->getValue() | LHSKnown.Zero).isAllOnesValue())
           return BinaryOperator::CreateSub(ConstantExpr::getAdd(XorRHS, CI),
                                            XorLHS);
@@ -1577,8 +1572,7 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
     // Turn this into a xor if LHS is 2^n-1 and the remaining bits are known
     // zero.
     if (Op0C->isMask()) {
-      KnownBits RHSKnown(BitWidth);
-      computeKnownBits(Op1, RHSKnown, 0, &I);
+      KnownBits RHSKnown = computeKnownBits(Op1, 0, &I);
       if ((*Op0C | RHSKnown.Zero).isAllOnesValue())
         return BinaryOperator::CreateXor(Op1, Op0);
     }

lib/Transforms/InstCombine/InstCombineCalls.cpp

@@ -1378,9 +1378,7 @@ static Instruction *foldCttzCtlz(IntrinsicInst &II, InstCombiner &IC) {
   if (!IT)
     return nullptr;
 
-  unsigned BitWidth = IT->getBitWidth();
-  KnownBits Known(BitWidth);
-  IC.computeKnownBits(Op0, Known, 0, &II);
+  KnownBits Known = IC.computeKnownBits(Op0, 0, &II);
 
   // Create a mask for bits above (ctlz) or below (cttz) the first known one.
   bool IsTZ = II.getIntrinsicID() == Intrinsic::cttz;

lib/Transforms/InstCombine/InstCombineCasts.cpp

@@ -692,8 +692,7 @@ Instruction *InstCombiner::transformZExtICmp(ICmpInst *ICI, ZExtInst &CI,
         // This only works for EQ and NE
         ICI->isEquality()) {
       // If Op1C some other power of two, convert:
-      KnownBits Known(Op1C->getType()->getBitWidth());
-      computeKnownBits(ICI->getOperand(0), Known, 0, &CI);
+      KnownBits Known = computeKnownBits(ICI->getOperand(0), 0, &CI);
 
       APInt KnownZeroMask(~Known.Zero);
       if (KnownZeroMask.isPowerOf2()) { // Exactly 1 possible 1?
@@ -737,14 +736,11 @@ Instruction *InstCombiner::transformZExtICmp(ICmpInst *ICI, ZExtInst &CI,
   // may lead to additional simplifications.
   if (ICI->isEquality() && CI.getType() == ICI->getOperand(0)->getType()) {
     if (IntegerType *ITy = dyn_cast<IntegerType>(CI.getType())) {
-      uint32_t BitWidth = ITy->getBitWidth();
       Value *LHS = ICI->getOperand(0);
       Value *RHS = ICI->getOperand(1);
 
-      KnownBits KnownLHS(BitWidth);
-      KnownBits KnownRHS(BitWidth);
-      computeKnownBits(LHS, KnownLHS, 0, &CI);
-      computeKnownBits(RHS, KnownRHS, 0, &CI);
+      KnownBits KnownLHS = computeKnownBits(LHS, 0, &CI);
+      KnownBits KnownRHS = computeKnownBits(RHS, 0, &CI);
 
       if (KnownLHS.Zero == KnownRHS.Zero && KnownLHS.One == KnownRHS.One) {
         APInt KnownBits = KnownLHS.Zero | KnownLHS.One;
@@ -1063,9 +1059,7 @@ Instruction *InstCombiner::transformSExtICmp(ICmpInst *ICI, Instruction &CI) {
     // the icmp and sext into bitwise/integer operations.
     if (ICI->hasOneUse() &&
         ICI->isEquality() && (Op1C->isZero() || Op1C->getValue().isPowerOf2())){
-      unsigned BitWidth = Op1C->getType()->getBitWidth();
-      KnownBits Known(BitWidth);
-      computeKnownBits(Op0, Known, 0, &CI);
+      KnownBits Known = computeKnownBits(Op0, 0, &CI);
 
       APInt KnownZeroMask(~Known.Zero);
       if (KnownZeroMask.isPowerOf2()) {
@@ -1104,7 +1098,7 @@ Instruction *InstCombiner::transformSExtICmp(ICmpInst *ICI, Instruction &CI) {
 
           // Distribute the bit over the whole bit width.
           In = Builder->CreateAShr(In, ConstantInt::get(In->getType(),
-                                                        BitWidth - 1), "sext");
+                                      KnownZeroMask.getBitWidth() - 1), "sext");
         }
 
         if (CI.getType() == In->getType())

lib/Transforms/InstCombine/InstCombineCompares.cpp

@@ -1478,8 +1478,7 @@ Instruction *InstCombiner::foldICmpTruncConstant(ICmpInst &Cmp,
     // of the high bits truncated out of x are known.
     unsigned DstBits = Trunc->getType()->getScalarSizeInBits(),
              SrcBits = X->getType()->getScalarSizeInBits();
-    KnownBits Known(SrcBits);
-    computeKnownBits(X, Known, 0, &Cmp);
+    KnownBits Known = computeKnownBits(X, 0, &Cmp);
 
     // If all the high bits are known, we can do this xform.
     if ((Known.Zero | Known.One).countLeadingOnes() >= SrcBits - DstBits) {

lib/Transforms/InstCombine/InstructionCombining.cpp

@@ -2180,8 +2180,7 @@ Instruction *InstCombiner::visitReturnInst(ReturnInst &RI) {
 
   // There might be assume intrinsics dominating this return that completely
   // determine the value. If so, constant fold it.
-  KnownBits Known(VTy->getPrimitiveSizeInBits());
-  computeKnownBits(ResultOp, Known, 0, &RI);
+  KnownBits Known = computeKnownBits(ResultOp, 0, &RI);
   if (Known.isConstant())
     RI.setOperand(0, Constant::getIntegerValue(VTy, Known.getConstant()));
 
@@ -2242,9 +2241,7 @@ Instruction *InstCombiner::visitSwitchInst(SwitchInst &SI) {
     return &SI;
   }
 
-  unsigned BitWidth = cast<IntegerType>(Cond->getType())->getBitWidth();
-  KnownBits Known(BitWidth);
-  computeKnownBits(Cond, Known, 0, &SI);
+  KnownBits Known = computeKnownBits(Cond, 0, &SI);
   unsigned LeadingKnownZeros = Known.countMinLeadingZeros();
   unsigned LeadingKnownOnes = Known.countMinLeadingOnes();
 
@@ -2257,12 +2254,12 @@ Instruction *InstCombiner::visitSwitchInst(SwitchInst &SI) {
         LeadingKnownOnes, C.getCaseValue()->getValue().countLeadingOnes());
   }
 
-  unsigned NewWidth = BitWidth - std::max(LeadingKnownZeros, LeadingKnownOnes);
+  unsigned NewWidth = Known.getBitWidth() - std::max(LeadingKnownZeros, LeadingKnownOnes);
 
   // Shrink the condition operand if the new type is smaller than the old type.
   // This may produce a non-standard type for the switch, but that's ok because
   // the backend should extend back to a legal type for the target.
-  if (NewWidth > 0 && NewWidth < BitWidth) {
+  if (NewWidth > 0 && NewWidth < Known.getBitWidth()) {
     IntegerType *Ty = IntegerType::get(SI.getContext(), NewWidth);
     Builder->SetInsertPoint(&SI);
     Value *NewCond = Builder->CreateTrunc(Cond, Ty, "trunc");
@@ -2841,9 +2838,7 @@ bool InstCombiner::run() {
     // a value even when the operands are not all constants.
     Type *Ty = I->getType();
     if (ExpensiveCombines && !I->use_empty() && Ty->isIntOrIntVectorTy()) {
-      unsigned BitWidth = Ty->getScalarSizeInBits();
-      KnownBits Known(BitWidth);
-      computeKnownBits(I, Known, /*Depth*/0, I);
+      KnownBits Known = computeKnownBits(I, /*Depth*/0, I);
       if (Known.isConstant()) {
         Constant *C = ConstantInt::get(Ty, Known.getConstant());
         DEBUG(dbgs() << "IC: ConstFold (all bits known) to: " << *C <<

lib/Transforms/Scalar/GuardWidening.cpp

@@ -537,9 +537,7 @@ bool GuardWideningImpl::parseRangeChecks(
       Changed = true;
     } else if (match(Check.getBase(),
                      m_Or(m_Value(OpLHS), m_ConstantInt(OpRHS)))) {
-      unsigned BitWidth = OpLHS->getType()->getScalarSizeInBits();
-      KnownBits Known(BitWidth);
-      computeKnownBits(OpLHS, Known, DL);
+      KnownBits Known = computeKnownBits(OpLHS, DL);
       if ((OpRHS->getValue() & Known.Zero) == OpRHS->getValue()) {
         Check.setBase(OpLHS);
         APInt NewOffset = Check.getOffsetValue() + OpRHS->getValue();

lib/Transforms/Utils/Local.cpp

@@ -1037,17 +1037,15 @@ unsigned llvm::getOrEnforceKnownAlignment(Value *V, unsigned PrefAlign,
                                           const DominatorTree *DT) {
   assert(V->getType()->isPointerTy() &&
          "getOrEnforceKnownAlignment expects a pointer!");
-  unsigned BitWidth = DL.getPointerTypeSizeInBits(V->getType());
 
-  KnownBits Known(BitWidth);
-  computeKnownBits(V, Known, DL, 0, AC, CxtI, DT);
+  KnownBits Known = computeKnownBits(V, DL, 0, AC, CxtI, DT);
   unsigned TrailZ = Known.countMinTrailingZeros();
 
   // Avoid trouble with ridiculously large TrailZ values, such as
   // those computed from a null pointer.
   TrailZ = std::min(TrailZ, unsigned(sizeof(unsigned) * CHAR_BIT - 1));
 
-  unsigned Align = 1u << std::min(BitWidth - 1, TrailZ);
+  unsigned Align = 1u << std::min(Known.getBitWidth() - 1, TrailZ);
 
   // LLVM doesn't support alignments larger than this currently.
   Align = std::min(Align, +Value::MaximumAlignment);

lib/Transforms/Utils/SimplifyCFG.cpp

@@ -4368,8 +4368,7 @@ static bool EliminateDeadSwitchCases(SwitchInst *SI, AssumptionCache *AC,
                                      const DataLayout &DL) {
   Value *Cond = SI->getCondition();
   unsigned Bits = Cond->getType()->getIntegerBitWidth();
-  KnownBits Known(Bits);
-  computeKnownBits(Cond, Known, DL, 0, AC, SI);
+  KnownBits Known = computeKnownBits(Cond, DL, 0, AC, SI);
 
   // We can also eliminate cases by determining that their values are outside of
   // the limited range of the condition based on how many significant (non-sign)

lib/Transforms/Utils/SimplifyLibCalls.cpp

@@ -466,9 +466,7 @@ Value *LibCallSimplifier::optimizeStringLength(CallInst *CI, IRBuilder<> &B,
       }
 
       Value *Offset = GEP->getOperand(2);
-      unsigned BitWidth = Offset->getType()->getIntegerBitWidth();
-      KnownBits Known(BitWidth);
-      computeKnownBits(Offset, Known, DL, 0, nullptr, CI, nullptr);
+      KnownBits Known = computeKnownBits(Offset, DL, 0, nullptr, CI, nullptr);
       Known.Zero.flipAllBits();
       uint64_t ArrSize =
              cast<ArrayType>(GEP->getSourceElementType())->getNumElements();