#include "InstCombine.h"
#include "llvm/Analysis/InstructionSimplify.h"
+#include "llvm/IR/ConstantRange.h"
#include "llvm/IR/Intrinsics.h"
-#include "llvm/Support/ConstantRange.h"
-#include "llvm/Support/PatternMatch.h"
+#include "llvm/IR/PatternMatch.h"
#include "llvm/Transforms/Utils/CmpInstAnalysis.h"
using namespace llvm;
using namespace PatternMatch;
-
-/// AddOne - Add one to a ConstantInt.
-static Constant *AddOne(ConstantInt *C) {
- return ConstantInt::get(C->getContext(), C->getValue() + 1);
-}
-/// SubOne - Subtract one from a ConstantInt.
-static Constant *SubOne(ConstantInt *C) {
- return ConstantInt::get(C->getContext(), C->getValue()-1);
-}
+#define DEBUG_TYPE "instcombine"
/// isFreeToInvert - Return true if the specified value is free to invert (apply
/// ~ to). This happens in cases where the ~ can be eliminated.
// Constants can be considered to be not'ed values...
if (ConstantInt *C = dyn_cast<ConstantInt>(V))
return ConstantInt::get(C->getType(), ~C->getValue());
- return 0;
+ return nullptr;
}
/// getFCmpCode - Similar to getICmpCode but for FCmpInst. This encodes a fcmp
ConstantInt *AndRHS,
BinaryOperator &TheAnd) {
Value *X = Op->getOperand(0);
- Constant *Together = 0;
+ Constant *Together = nullptr;
if (!Op->isShift())
Together = ConstantExpr::getAnd(AndRHS, OpRHS);
}
break;
}
- return 0;
+ return nullptr;
}
/// Emit a computation of: (V >= Lo && V < Hi) if Inside is true, otherwise
Instruction &I) {
Instruction *LHSI = dyn_cast<Instruction>(LHS);
if (!LHSI || LHSI->getNumOperands() != 2 ||
- !isa<ConstantInt>(LHSI->getOperand(1))) return 0;
+ !isa<ConstantInt>(LHSI->getOperand(1))) return nullptr;
ConstantInt *N = cast<ConstantInt>(LHSI->getOperand(1));
switch (LHSI->getOpcode()) {
- default: return 0;
+ default: return nullptr;
case Instruction::And:
if (ConstantExpr::getAnd(N, Mask) == Mask) {
// If the AndRHS is a power of two minus one (0+1+), this is simple.
break;
}
}
- return 0;
+ return nullptr;
case Instruction::Or:
case Instruction::Xor:
// If the AndRHS is a power of two minus one (0+1+), and N&Mask == 0
Mask->getValue().countPopulation()) == Mask->getValue().getBitWidth()
&& ConstantExpr::getAnd(N, Mask)->isNullValue())
break;
- return 0;
+ return nullptr;
}
if (isSub)
ConstantInt *BCst = dyn_cast<ConstantInt>(B);
ConstantInt *CCst = dyn_cast<ConstantInt>(C);
bool icmp_eq = (SCC == ICmpInst::ICMP_EQ);
- bool icmp_abit = (ACst != 0 && !ACst->isZero() &&
+ bool icmp_abit = (ACst && !ACst->isZero() &&
ACst->getValue().isPowerOf2());
- bool icmp_bbit = (BCst != 0 && !BCst->isZero() &&
+ bool icmp_bbit = (BCst && !BCst->isZero() &&
BCst->getValue().isPowerOf2());
unsigned result = 0;
- if (CCst != 0 && CCst->isZero()) {
+ if (CCst && CCst->isZero()) {
// if C is zero, then both A and B qualify as mask
result |= (icmp_eq ? (FoldMskICmp_Mask_AllZeroes |
FoldMskICmp_Mask_AllZeroes |
FoldMskICmp_AMask_NotMixed)
: (FoldMskICmp_Mask_AllZeroes |
FoldMskICmp_AMask_Mixed));
- } else if (ACst != 0 && CCst != 0 &&
+ } else if (ACst && CCst &&
ConstantExpr::getAnd(ACst, CCst) == CCst) {
result |= (icmp_eq ? FoldMskICmp_AMask_Mixed
: FoldMskICmp_AMask_NotMixed);
FoldMskICmp_BMask_NotMixed)
: (FoldMskICmp_Mask_AllZeroes |
FoldMskICmp_BMask_Mixed));
- } else if (BCst != 0 && CCst != 0 &&
+ } else if (BCst && CCst &&
ConstantExpr::getAnd(BCst, CCst) == CCst) {
result |= (icmp_eq ? FoldMskICmp_BMask_Mixed
: FoldMskICmp_BMask_NotMixed);
return result;
}
+/// Convert an analysis of a masked ICmp into its equivalent if all boolean
+/// operations had the opposite sense. Since each "NotXXX" flag (recording !=)
+/// is adjacent to the corresponding normal flag (recording ==), this just
+/// involves swapping those bits over.
+static unsigned conjugateICmpMask(unsigned Mask) {
+ unsigned NewMask;
+ NewMask = (Mask & (FoldMskICmp_AMask_AllOnes | FoldMskICmp_BMask_AllOnes |
+ FoldMskICmp_Mask_AllZeroes | FoldMskICmp_AMask_Mixed |
+ FoldMskICmp_BMask_Mixed))
+ << 1;
+
+ NewMask |=
+ (Mask & (FoldMskICmp_AMask_NotAllOnes | FoldMskICmp_BMask_NotAllOnes |
+ FoldMskICmp_Mask_NotAllZeroes | FoldMskICmp_AMask_NotMixed |
+ FoldMskICmp_BMask_NotMixed))
+ >> 1;
+
+ return NewMask;
+}
+
/// decomposeBitTestICmp - Decompose an icmp into the form ((X & Y) pred Z)
/// if possible. The returned predicate is either == or !=. Returns false if
/// decomposition fails.
static bool decomposeBitTestICmp(const ICmpInst *I, ICmpInst::Predicate &Pred,
Value *&X, Value *&Y, Value *&Z) {
- // X < 0 is equivalent to (X & SignBit) != 0.
- if (I->getPredicate() == ICmpInst::ICMP_SLT)
- if (ConstantInt *C = dyn_cast<ConstantInt>(I->getOperand(1)))
- if (C->isZero()) {
- X = I->getOperand(0);
- Y = ConstantInt::get(I->getContext(),
- APInt::getSignBit(C->getBitWidth()));
- Pred = ICmpInst::ICMP_NE;
- Z = C;
- return true;
- }
+ ConstantInt *C = dyn_cast<ConstantInt>(I->getOperand(1));
+ if (!C)
+ return false;
- // X > -1 is equivalent to (X & SignBit) == 0.
- if (I->getPredicate() == ICmpInst::ICMP_SGT)
- if (ConstantInt *C = dyn_cast<ConstantInt>(I->getOperand(1)))
- if (C->isAllOnesValue()) {
- X = I->getOperand(0);
- Y = ConstantInt::get(I->getContext(),
- APInt::getSignBit(C->getBitWidth()));
- Pred = ICmpInst::ICMP_EQ;
- Z = ConstantInt::getNullValue(C->getType());
- return true;
- }
+ switch (I->getPredicate()) {
+ default:
+ return false;
+ case ICmpInst::ICMP_SLT:
+ // X < 0 is equivalent to (X & SignBit) != 0.
+ if (!C->isZero())
+ return false;
+ Y = ConstantInt::get(I->getContext(), APInt::getSignBit(C->getBitWidth()));
+ Pred = ICmpInst::ICMP_NE;
+ break;
+ case ICmpInst::ICMP_SGT:
+ // X > -1 is equivalent to (X & SignBit) == 0.
+ if (!C->isAllOnesValue())
+ return false;
+ Y = ConstantInt::get(I->getContext(), APInt::getSignBit(C->getBitWidth()));
+ Pred = ICmpInst::ICMP_EQ;
+ break;
+ case ICmpInst::ICMP_ULT:
+ // X <u 2^n is equivalent to (X & ~(2^n-1)) == 0.
+ if (!C->getValue().isPowerOf2())
+ return false;
+ Y = ConstantInt::get(I->getContext(), -C->getValue());
+ Pred = ICmpInst::ICMP_EQ;
+ break;
+ case ICmpInst::ICMP_UGT:
+ // X >u 2^n-1 is equivalent to (X & ~(2^n-1)) != 0.
+ if (!(C->getValue() + 1).isPowerOf2())
+ return false;
+ Y = ConstantInt::get(I->getContext(), ~C->getValue());
+ Pred = ICmpInst::ICMP_NE;
+ break;
+ }
- return false;
+ X = I->getOperand(0);
+ Z = ConstantInt::getNullValue(C->getType());
+ return true;
}
/// foldLogOpOfMaskedICmpsHelper:
Value *L11,*L12,*L21,*L22;
// Check whether the icmp can be decomposed into a bit test.
if (decomposeBitTestICmp(LHS, LHSCC, L11, L12, L2)) {
- L21 = L22 = L1 = 0;
+ L21 = L22 = L1 = nullptr;
} else {
// Look for ANDs in the LHS icmp.
- if (match(L1, m_And(m_Value(L11), m_Value(L12)))) {
- if (!match(L2, m_And(m_Value(L21), m_Value(L22))))
- L21 = L22 = 0;
- } else {
- if (!match(L2, m_And(m_Value(L11), m_Value(L12))))
- return 0;
- std::swap(L1, L2);
- L21 = L22 = 0;
+ if (!L1->getType()->isIntegerTy()) {
+ // You can icmp pointers, for example. They really aren't masks.
+ L11 = L12 = nullptr;
+ } else if (!match(L1, m_And(m_Value(L11), m_Value(L12)))) {
+ // Any icmp can be viewed as being trivially masked; if it allows us to
+ // remove one, it's worth it.
+ L11 = L1;
+ L12 = Constant::getAllOnesValue(L1->getType());
+ }
+
+ if (!L2->getType()->isIntegerTy()) {
+ // You can icmp pointers, for example. They really aren't masks.
+ L21 = L22 = nullptr;
+ } else if (!match(L2, m_And(m_Value(L21), m_Value(L22)))) {
+ L21 = L2;
+ L22 = Constant::getAllOnesValue(L2->getType());
}
}
} else {
return 0;
}
- E = R2; R1 = 0; ok = true;
- } else if (match(R1, m_And(m_Value(R11), m_Value(R12)))) {
+ E = R2; R1 = nullptr; ok = true;
+ } else if (R1->getType()->isIntegerTy()) {
+ if (!match(R1, m_And(m_Value(R11), m_Value(R12)))) {
+ // As before, model no mask as a trivial mask if it'll let us do an
+ // optimisation.
+ R11 = R1;
+ R12 = Constant::getAllOnesValue(R1->getType());
+ }
+
if (R11 == L11 || R11 == L12 || R11 == L21 || R11 == L22) {
A = R11; D = R12; E = R2; ok = true;
} else if (R12 == L11 || R12 == L12 || R12 == L21 || R12 == L22) {
return 0;
// Look for ANDs in on the right side of the RHS icmp.
- if (!ok && match(R2, m_And(m_Value(R11), m_Value(R12)))) {
+ if (!ok && R2->getType()->isIntegerTy()) {
+ if (!match(R2, m_And(m_Value(R11), m_Value(R12)))) {
+ R11 = R2;
+ R12 = Constant::getAllOnesValue(R2->getType());
+ }
+
if (R11 == L11 || R11 == L12 || R11 == L21 || R11 == L22) {
A = R11; D = R12; E = R1; ok = true;
} else if (R12 == L11 || R12 == L12 || R12 == L21 || R12 == L22) {
/// foldLogOpOfMaskedICmps:
/// try to fold (icmp(A & B) ==/!= C) &/| (icmp(A & D) ==/!= E)
/// into a single (icmp(A & X) ==/!= Y)
-static Value* foldLogOpOfMaskedICmps(ICmpInst *LHS, ICmpInst *RHS,
- ICmpInst::Predicate NEWCC,
+static Value* foldLogOpOfMaskedICmps(ICmpInst *LHS, ICmpInst *RHS, bool IsAnd,
llvm::InstCombiner::BuilderTy* Builder) {
- Value *A = 0, *B = 0, *C = 0, *D = 0, *E = 0;
+ Value *A = nullptr, *B = nullptr, *C = nullptr, *D = nullptr, *E = nullptr;
ICmpInst::Predicate LHSCC = LHS->getPredicate(), RHSCC = RHS->getPredicate();
unsigned mask = foldLogOpOfMaskedICmpsHelper(A, B, C, D, E, LHS, RHS,
LHSCC, RHSCC);
- if (mask == 0) return 0;
+ if (mask == 0) return nullptr;
assert(ICmpInst::isEquality(LHSCC) && ICmpInst::isEquality(RHSCC) &&
"foldLogOpOfMaskedICmpsHelper must return an equality predicate.");
- if (NEWCC == ICmpInst::ICMP_NE)
- mask >>= 1; // treat "Not"-states as normal states
+ // In full generality:
+ // (icmp (A & B) Op C) | (icmp (A & D) Op E)
+ // == ![ (icmp (A & B) !Op C) & (icmp (A & D) !Op E) ]
+ //
+ // If the latter can be converted into (icmp (A & X) Op Y) then the former is
+ // equivalent to (icmp (A & X) !Op Y).
+ //
+ // Therefore, we can pretend for the rest of this function that we're dealing
+ // with the conjunction, provided we flip the sense of any comparisons (both
+ // input and output).
+
+ // In most cases we're going to produce an EQ for the "&&" case.
+ ICmpInst::Predicate NEWCC = IsAnd ? ICmpInst::ICMP_EQ : ICmpInst::ICMP_NE;
+ if (!IsAnd) {
+ // Convert the masking analysis into its equivalent with negated
+ // comparisons.
+ mask = conjugateICmpMask(mask);
+ }
if (mask & FoldMskICmp_Mask_AllZeroes) {
// (icmp eq (A & B), 0) & (icmp eq (A & D), 0)
Value* newAnd = Builder->CreateAnd(A, newAnd1);
return Builder->CreateICmp(NEWCC, newAnd, A);
}
+
+ // Remaining cases assume at least that B and D are constant, and depend on
+ // their actual values. This isn't strictly, necessary, just a "handle the
+ // easy cases for now" decision.
+ ConstantInt *BCst = dyn_cast<ConstantInt>(B);
+ if (!BCst) return nullptr;
+ ConstantInt *DCst = dyn_cast<ConstantInt>(D);
+ if (!DCst) return nullptr;
+
+ if (mask & (FoldMskICmp_Mask_NotAllZeroes | FoldMskICmp_BMask_NotAllOnes)) {
+ // (icmp ne (A & B), 0) & (icmp ne (A & D), 0) and
+ // (icmp ne (A & B), B) & (icmp ne (A & D), D)
+ // -> (icmp ne (A & B), 0) or (icmp ne (A & D), 0)
+ // Only valid if one of the masks is a superset of the other (check "B&D" is
+ // the same as either B or D).
+ APInt NewMask = BCst->getValue() & DCst->getValue();
+
+ if (NewMask == BCst->getValue())
+ return LHS;
+ else if (NewMask == DCst->getValue())
+ return RHS;
+ }
+ if (mask & FoldMskICmp_AMask_NotAllOnes) {
+ // (icmp ne (A & B), B) & (icmp ne (A & D), D)
+ // -> (icmp ne (A & B), A) or (icmp ne (A & D), A)
+ // Only valid if one of the masks is a superset of the other (check "B|D" is
+ // the same as either B or D).
+ APInt NewMask = BCst->getValue() | DCst->getValue();
+
+ if (NewMask == BCst->getValue())
+ return LHS;
+ else if (NewMask == DCst->getValue())
+ return RHS;
+ }
if (mask & FoldMskICmp_BMask_Mixed) {
// (icmp eq (A & B), C) & (icmp eq (A & D), E)
// We already know that B & C == C && D & E == E.
// contradict, then we can transform to
// -> (icmp eq (A & (B|D)), (C|E))
// Currently, we only handle the case of B, C, D, and E being constant.
- ConstantInt *BCst = dyn_cast<ConstantInt>(B);
- if (BCst == 0) return 0;
- ConstantInt *DCst = dyn_cast<ConstantInt>(D);
- if (DCst == 0) return 0;
// we can't simply use C and E, because we might actually handle
// (icmp ne (A & B), B) & (icmp eq (A & D), D)
// with B and D, having a single bit set
-
ConstantInt *CCst = dyn_cast<ConstantInt>(C);
- if (CCst == 0) return 0;
+ if (!CCst) return nullptr;
if (LHSCC != NEWCC)
CCst = dyn_cast<ConstantInt>( ConstantExpr::getXor(BCst, CCst) );
ConstantInt *ECst = dyn_cast<ConstantInt>(E);
- if (ECst == 0) return 0;
+ if (!ECst) return nullptr;
if (RHSCC != NEWCC)
ECst = dyn_cast<ConstantInt>( ConstantExpr::getXor(DCst, ECst) );
ConstantInt* MCst = dyn_cast<ConstantInt>(
// if there is a conflict we should actually return a false for the
// whole construct
if (!MCst->isZero())
- return 0;
+ return nullptr;
Value *newOr1 = Builder->CreateOr(B, D);
Value *newOr2 = ConstantExpr::getOr(CCst, ECst);
Value *newAnd = Builder->CreateAnd(A, newOr1);
return Builder->CreateICmp(NEWCC, newAnd, newOr2);
}
- return 0;
+ return nullptr;
}
/// FoldAndOfICmps - Fold (icmp)&(icmp) if possible.
}
// handle (roughly): (icmp eq (A & B), C) & (icmp eq (A & D), E)
- if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, ICmpInst::ICMP_EQ, Builder))
+ if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, true, Builder))
return V;
// This only handles icmp of constants: (icmp1 A, C1) & (icmp2 B, C2).
Value *Val = LHS->getOperand(0), *Val2 = RHS->getOperand(0);
ConstantInt *LHSCst = dyn_cast<ConstantInt>(LHS->getOperand(1));
ConstantInt *RHSCst = dyn_cast<ConstantInt>(RHS->getOperand(1));
- if (LHSCst == 0 || RHSCst == 0) return 0;
+ if (!LHSCst || !RHSCst) return nullptr;
if (LHSCst == RHSCst && LHSCC == RHSCC) {
// (icmp ult A, C) & (icmp ult B, C) --> (icmp ult (A|B), C)
if (LHSCC == ICmpInst::ICMP_EQ && LHSCC == RHSCC &&
LHS->hasOneUse() && RHS->hasOneUse()) {
Value *V;
- ConstantInt *AndCst, *SmallCst = 0, *BigCst = 0;
+ ConstantInt *AndCst, *SmallCst = nullptr, *BigCst = nullptr;
// (trunc x) == C1 & (and x, CA) == C2
// (and x, CA) == C2 & (trunc x) == C1
// From here on, we only handle:
// (icmp1 A, C1) & (icmp2 A, C2) --> something simpler.
- if (Val != Val2) return 0;
+ if (Val != Val2) return nullptr;
// ICMP_[US][GL]E X, CST is folded to ICMP_[US][GL]T elsewhere.
if (LHSCC == ICmpInst::ICMP_UGE || LHSCC == ICmpInst::ICMP_ULE ||
RHSCC == ICmpInst::ICMP_UGE || RHSCC == ICmpInst::ICMP_ULE ||
LHSCC == ICmpInst::ICMP_SGE || LHSCC == ICmpInst::ICMP_SLE ||
RHSCC == ICmpInst::ICMP_SGE || RHSCC == ICmpInst::ICMP_SLE)
- return 0;
+ return nullptr;
// Make a constant range that's the intersection of the two icmp ranges.
// If the intersection is empty, we know that the result is false.
// We can't fold (ugt x, C) & (sgt x, C2).
if (!PredicatesFoldable(LHSCC, RHSCC))
- return 0;
+ return nullptr;
// Ensure that the larger constant is on the RHS.
bool ShouldSwap;
case ICmpInst::ICMP_SGT: // (X != 13 & X s> 15) -> X s> 15
return RHS;
case ICmpInst::ICMP_NE:
+ // Special case to get the ordering right when the values wrap around
+ // zero.
+ if (LHSCst->getValue() == 0 && RHSCst->getValue().isAllOnesValue())
+ std::swap(LHSCst, RHSCst);
if (LHSCst == SubOne(RHSCst)){// (X != 13 & X != 14) -> X-13 >u 1
Constant *AddCST = ConstantExpr::getNeg(LHSCst);
Value *Add = Builder->CreateAdd(Val, AddCST, Val->getName()+".off");
- return Builder->CreateICmpUGT(Add, ConstantInt::get(Add->getType(), 1));
+ return Builder->CreateICmpUGT(Add, ConstantInt::get(Add->getType(), 1),
+ Val->getName()+".cmp");
}
break; // (X != 13 & X != 15) -> no change
}
break;
}
- return 0;
+ return nullptr;
}
/// FoldAndOfFCmps - Optimize (fcmp)&(fcmp). NOTE: Unlike the rest of
if (LHS->getPredicate() == FCmpInst::FCMP_ORD &&
RHS->getPredicate() == FCmpInst::FCMP_ORD) {
if (LHS->getOperand(0)->getType() != RHS->getOperand(0)->getType())
- return 0;
+ return nullptr;
// (fcmp ord x, c) & (fcmp ord y, c) -> (fcmp ord x, y)
if (ConstantFP *LHSC = dyn_cast<ConstantFP>(LHS->getOperand(1)))
if (isa<ConstantAggregateZero>(LHS->getOperand(1)) &&
isa<ConstantAggregateZero>(RHS->getOperand(1)))
return Builder->CreateFCmpORD(LHS->getOperand(0), RHS->getOperand(0));
- return 0;
+ return nullptr;
}
Value *Op0LHS = LHS->getOperand(0), *Op0RHS = LHS->getOperand(1);
}
}
- return 0;
+ return nullptr;
}
bool Changed = SimplifyAssociativeOrCommutative(I);
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
- if (Value *V = SimplifyAndInst(Op0, Op1, TD))
+ if (Value *V = SimplifyVectorOp(I))
+ return ReplaceInstUsesWith(I, V);
+
+ if (Value *V = SimplifyAndInst(Op0, Op1, DL))
return ReplaceInstUsesWith(I, V);
// (A|B)&(A|C) -> A|(B&C) etc
// If this is an integer truncation, and if the source is an 'and' with
// immediate, transform it. This frequently occurs for bitfield accesses.
{
- Value *X = 0; ConstantInt *YC = 0;
+ Value *X = nullptr; ConstantInt *YC = nullptr;
if (match(Op0, m_Trunc(m_And(m_Value(X), m_ConstantInt(YC))))) {
// Change: and (trunc (and X, YC) to T), C2
// into : and (trunc X to T), trunc(YC) & C2
}
{
- Value *A = 0, *B = 0, *C = 0, *D = 0;
+ Value *A = nullptr, *B = nullptr, *C = nullptr, *D = nullptr;
// (A|B) & ~(A&B) -> A^B
if (match(Op0, m_Or(m_Value(A), m_Value(B))) &&
match(Op1, m_Not(m_And(m_Value(C), m_Value(D)))) &&
}
{
- Value *X = 0;
+ Value *X = nullptr;
bool OpsSwapped = false;
// Canonicalize SExt or Not to the LHS
if (match(Op1, m_SExt(m_Value())) ||
std::swap(Op0, Op1);
}
- return Changed ? &I : 0;
+ return Changed ? &I : nullptr;
}
/// CollectBSwapParts - Analyze the specified subexpression and see if it is
if (!ITy || ITy->getBitWidth() % 16 ||
// ByteMask only allows up to 32-byte values.
ITy->getBitWidth() > 32*8)
- return 0; // Can only bswap pairs of bytes. Can't do vectors.
+ return nullptr; // Can only bswap pairs of bytes. Can't do vectors.
/// ByteValues - For each byte of the result, we keep track of which value
/// defines each byte.
// Try to find all the pieces corresponding to the bswap.
uint32_t ByteMask = ~0U >> (32-ByteValues.size());
if (CollectBSwapParts(&I, 0, ByteMask, ByteValues))
- return 0;
+ return nullptr;
// Check to see if all of the bytes come from the same value.
Value *V = ByteValues[0];
- if (V == 0) return 0; // Didn't find a byte? Must be zero.
+ if (!V) return nullptr; // Didn't find a byte? Must be zero.
// Check to make sure that all of the bytes come from the same value.
for (unsigned i = 1, e = ByteValues.size(); i != e; ++i)
if (ByteValues[i] != V)
- return 0;
+ return nullptr;
Module *M = I.getParent()->getParent()->getParent();
Function *F = Intrinsic::getDeclaration(M, Intrinsic::bswap, ITy);
return CallInst::Create(F, V);
static Instruction *MatchSelectFromAndOr(Value *A, Value *B,
Value *C, Value *D) {
// If A is not a select of -1/0, this cannot match.
- Value *Cond = 0;
+ Value *Cond = nullptr;
if (!match(A, m_SExt(m_Value(Cond))) ||
!Cond->getType()->isIntegerTy(1))
- return 0;
+ return nullptr;
// ((cond?-1:0)&C) | (B&(cond?0:-1)) -> cond ? C : B.
if (match(D, m_Not(m_SExt(m_Specific(Cond)))))
return SelectInst::Create(Cond, C, D);
if (match(B, m_SExt(m_Not(m_Specific(Cond)))))
return SelectInst::Create(Cond, C, D);
- return 0;
+ return nullptr;
}
/// FoldOrOfICmps - Fold (icmp)|(icmp) if possible.
Value *InstCombiner::FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS) {
ICmpInst::Predicate LHSCC = LHS->getPredicate(), RHSCC = RHS->getPredicate();
+ // Fold (iszero(A & K1) | iszero(A & K2)) -> (A & (K1 | K2)) != (K1 | K2)
+ // if K1 and K2 are a one-bit mask.
+ ConstantInt *LHSCst = dyn_cast<ConstantInt>(LHS->getOperand(1));
+ ConstantInt *RHSCst = dyn_cast<ConstantInt>(RHS->getOperand(1));
+
+ if (LHS->getPredicate() == ICmpInst::ICMP_EQ && LHSCst && LHSCst->isZero() &&
+ RHS->getPredicate() == ICmpInst::ICMP_EQ && RHSCst && RHSCst->isZero()) {
+
+ BinaryOperator *LAnd = dyn_cast<BinaryOperator>(LHS->getOperand(0));
+ BinaryOperator *RAnd = dyn_cast<BinaryOperator>(RHS->getOperand(0));
+ if (LAnd && RAnd && LAnd->hasOneUse() && RHS->hasOneUse() &&
+ LAnd->getOpcode() == Instruction::And &&
+ RAnd->getOpcode() == Instruction::And) {
+
+ Value *Mask = nullptr;
+ Value *Masked = nullptr;
+ if (LAnd->getOperand(0) == RAnd->getOperand(0) &&
+ isKnownToBeAPowerOfTwo(LAnd->getOperand(1)) &&
+ isKnownToBeAPowerOfTwo(RAnd->getOperand(1))) {
+ Mask = Builder->CreateOr(LAnd->getOperand(1), RAnd->getOperand(1));
+ Masked = Builder->CreateAnd(LAnd->getOperand(0), Mask);
+ } else if (LAnd->getOperand(1) == RAnd->getOperand(1) &&
+ isKnownToBeAPowerOfTwo(LAnd->getOperand(0)) &&
+ isKnownToBeAPowerOfTwo(RAnd->getOperand(0))) {
+ Mask = Builder->CreateOr(LAnd->getOperand(0), RAnd->getOperand(0));
+ Masked = Builder->CreateAnd(LAnd->getOperand(1), Mask);
+ }
+
+ if (Masked)
+ return Builder->CreateICmp(ICmpInst::ICMP_NE, Masked, Mask);
+ }
+ }
+
// (icmp1 A, B) | (icmp2 A, B) --> (icmp3 A, B)
if (PredicatesFoldable(LHSCC, RHSCC)) {
if (LHS->getOperand(0) == RHS->getOperand(1) &&
// handle (roughly):
// (icmp ne (A & B), C) | (icmp ne (A & D), E)
- if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, ICmpInst::ICMP_NE, Builder))
+ if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, false, Builder))
return V;
Value *Val = LHS->getOperand(0), *Val2 = RHS->getOperand(0);
- ConstantInt *LHSCst = dyn_cast<ConstantInt>(LHS->getOperand(1));
- ConstantInt *RHSCst = dyn_cast<ConstantInt>(RHS->getOperand(1));
-
if (LHS->hasOneUse() || RHS->hasOneUse()) {
// (icmp eq B, 0) | (icmp ult A, B) -> (icmp ule A, B-1)
// (icmp eq B, 0) | (icmp ugt B, A) -> (icmp ule A, B-1)
- Value *A = 0, *B = 0;
+ Value *A = nullptr, *B = nullptr;
if (LHSCC == ICmpInst::ICMP_EQ && LHSCst && LHSCst->isZero()) {
B = Val;
if (RHSCC == ICmpInst::ICMP_ULT && Val == RHS->getOperand(1))
}
// This only handles icmp of constants: (icmp1 A, C1) | (icmp2 B, C2).
- if (LHSCst == 0 || RHSCst == 0) return 0;
+ if (!LHSCst || !RHSCst) return nullptr;
if (LHSCst == RHSCst && LHSCC == RHSCC) {
// (icmp ne A, 0) | (icmp ne B, 0) --> (icmp ne (A|B), 0)
// From here on, we only handle:
// (icmp1 A, C1) | (icmp2 A, C2) --> something simpler.
- if (Val != Val2) return 0;
+ if (Val != Val2) return nullptr;
// ICMP_[US][GL]E X, CST is folded to ICMP_[US][GL]T elsewhere.
if (LHSCC == ICmpInst::ICMP_UGE || LHSCC == ICmpInst::ICMP_ULE ||
RHSCC == ICmpInst::ICMP_UGE || RHSCC == ICmpInst::ICMP_ULE ||
LHSCC == ICmpInst::ICMP_SGE || LHSCC == ICmpInst::ICMP_SLE ||
RHSCC == ICmpInst::ICMP_SGE || RHSCC == ICmpInst::ICMP_SLE)
- return 0;
+ return nullptr;
// We can't fold (ugt x, C) | (sgt x, C2).
if (!PredicatesFoldable(LHSCC, RHSCC))
- return 0;
+ return nullptr;
// Ensure that the larger constant is on the RHS.
bool ShouldSwap;
}
break;
}
- return 0;
+ return nullptr;
}
/// FoldOrOfFCmps - Optimize (fcmp)|(fcmp). NOTE: Unlike the rest of
isa<ConstantAggregateZero>(RHS->getOperand(1)))
return Builder->CreateFCmpUNO(LHS->getOperand(0), RHS->getOperand(0));
- return 0;
+ return nullptr;
}
Value *Op0LHS = LHS->getOperand(0), *Op0RHS = LHS->getOperand(1);
return getFCmpValue(Op0Ordered, Op0Pred|Op1Pred, Op0LHS, Op0RHS, Builder);
}
}
- return 0;
+ return nullptr;
}
/// FoldOrWithConstants - This helper function folds:
Instruction *InstCombiner::FoldOrWithConstants(BinaryOperator &I, Value *Op,
Value *A, Value *B, Value *C) {
ConstantInt *CI1 = dyn_cast<ConstantInt>(C);
- if (!CI1) return 0;
+ if (!CI1) return nullptr;
- Value *V1 = 0;
- ConstantInt *CI2 = 0;
- if (!match(Op, m_And(m_Value(V1), m_ConstantInt(CI2)))) return 0;
+ Value *V1 = nullptr;
+ ConstantInt *CI2 = nullptr;
+ if (!match(Op, m_And(m_Value(V1), m_ConstantInt(CI2)))) return nullptr;
APInt Xor = CI1->getValue() ^ CI2->getValue();
- if (!Xor.isAllOnesValue()) return 0;
+ if (!Xor.isAllOnesValue()) return nullptr;
if (V1 == A || V1 == B) {
Value *NewOp = Builder->CreateAnd((V1 == A) ? B : A, CI1);
return BinaryOperator::CreateOr(NewOp, V1);
}
- return 0;
+ return nullptr;
}
Instruction *InstCombiner::visitOr(BinaryOperator &I) {
bool Changed = SimplifyAssociativeOrCommutative(I);
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
- if (Value *V = SimplifyOrInst(Op0, Op1, TD))
+ if (Value *V = SimplifyVectorOp(I))
+ return ReplaceInstUsesWith(I, V);
+
+ if (Value *V = SimplifyOrInst(Op0, Op1, DL))
return ReplaceInstUsesWith(I, V);
// (A&B)|(A&C) -> A&(B|C) etc
return &I;
if (ConstantInt *RHS = dyn_cast<ConstantInt>(Op1)) {
- ConstantInt *C1 = 0; Value *X = 0;
+ ConstantInt *C1 = nullptr; Value *X = nullptr;
// (X & C1) | C2 --> (X | C2) & (C1|C2)
// iff (C1 & C2) == 0.
if (match(Op0, m_And(m_Value(X), m_ConstantInt(C1))) &&
return NV;
}
- Value *A = 0, *B = 0;
- ConstantInt *C1 = 0, *C2 = 0;
+ Value *A = nullptr, *B = nullptr;
+ ConstantInt *C1 = nullptr, *C2 = nullptr;
// (A | B) | C and A | (B | C) -> bswap if possible.
// (A >> B) | (C << D) and (A << B) | (B >> C) -> bswap if possible.
}
// (A & C)|(B & D)
- Value *C = 0, *D = 0;
+ Value *C = nullptr, *D = nullptr;
if (match(Op0, m_And(m_Value(A), m_Value(C))) &&
match(Op1, m_And(m_Value(B), m_Value(D)))) {
- Value *V1 = 0, *V2 = 0;
+ Value *V1 = nullptr, *V2 = nullptr;
C1 = dyn_cast<ConstantInt>(C);
C2 = dyn_cast<ConstantInt>(D);
if (C1 && C2) { // (A & C1)|(B & C2)
// ((V|C3)&C1) | ((V|C4)&C2) --> (V|C3|C4)&(C1|C2)
// iff (C1&C2) == 0 and (C3&~C1) == 0 and (C4&~C2) == 0.
- ConstantInt *C3 = 0, *C4 = 0;
+ ConstantInt *C3 = nullptr, *C4 = nullptr;
if (match(A, m_Or(m_Value(V1), m_ConstantInt(C3))) &&
(C3->getValue() & ~C1->getValue()) == 0 &&
match(B, m_Or(m_Specific(V1), m_ConstantInt(C4))) &&
// Since this OR statement hasn't been optimized further yet, we hope
// that this transformation will allow the new ORs to be optimized.
{
- Value *X = 0, *Y = 0;
+ Value *X = nullptr, *Y = nullptr;
if (Op0->hasOneUse() && Op1->hasOneUse() &&
match(Op0, m_Select(m_Value(X), m_Value(A), m_Value(B))) &&
match(Op1, m_Select(m_Value(Y), m_Value(C), m_Value(D))) && X == Y) {
}
}
- return Changed ? &I : 0;
+ return Changed ? &I : nullptr;
}
Instruction *InstCombiner::visitXor(BinaryOperator &I) {
bool Changed = SimplifyAssociativeOrCommutative(I);
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
- if (Value *V = SimplifyXorInst(Op0, Op1, TD))
+ if (Value *V = SimplifyVectorOp(I))
+ return ReplaceInstUsesWith(I, V);
+
+ if (Value *V = SimplifyXorInst(Op0, Op1, DL))
return ReplaceInstUsesWith(I, V);
// (A&B)^(A&C) -> A&(B^C) etc
}
}
- return Changed ? &I : 0;
+ return Changed ? &I : nullptr;
}
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