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d9b2a4b5e7
"Does the predicate hold between two ranges?" Not very surprisingly, some places were already doing this check, without explicitly naming the algorithm, cleanup them all.
1702 lines
58 KiB
C++
1702 lines
58 KiB
C++
//===- ConstantRange.cpp - ConstantRange implementation -------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// Represent a range of possible values that may occur when the program is run
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// for an integral value. This keeps track of a lower and upper bound for the
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// constant, which MAY wrap around the end of the numeric range. To do this, it
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// keeps track of a [lower, upper) bound, which specifies an interval just like
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// STL iterators. When used with boolean values, the following are important
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// ranges (other integral ranges use min/max values for special range values):
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//
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// [F, F) = {} = Empty set
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// [T, F) = {T}
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// [F, T) = {F}
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// [T, T) = {F, T} = Full set
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/ADT/APInt.h"
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#include "llvm/Config/llvm-config.h"
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#include "llvm/IR/ConstantRange.h"
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#include "llvm/IR/Constants.h"
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#include "llvm/IR/InstrTypes.h"
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#include "llvm/IR/Instruction.h"
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#include "llvm/IR/Intrinsics.h"
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#include "llvm/IR/Metadata.h"
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#include "llvm/IR/Operator.h"
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#include "llvm/Support/Compiler.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/ErrorHandling.h"
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#include "llvm/Support/KnownBits.h"
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#include "llvm/Support/raw_ostream.h"
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#include <algorithm>
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#include <cassert>
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#include <cstdint>
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using namespace llvm;
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ConstantRange::ConstantRange(uint32_t BitWidth, bool Full)
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: Lower(Full ? APInt::getMaxValue(BitWidth) : APInt::getMinValue(BitWidth)),
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Upper(Lower) {}
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ConstantRange::ConstantRange(APInt V)
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: Lower(std::move(V)), Upper(Lower + 1) {}
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ConstantRange::ConstantRange(APInt L, APInt U)
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: Lower(std::move(L)), Upper(std::move(U)) {
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assert(Lower.getBitWidth() == Upper.getBitWidth() &&
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"ConstantRange with unequal bit widths");
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assert((Lower != Upper || (Lower.isMaxValue() || Lower.isMinValue())) &&
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"Lower == Upper, but they aren't min or max value!");
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}
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ConstantRange ConstantRange::fromKnownBits(const KnownBits &Known,
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bool IsSigned) {
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assert(!Known.hasConflict() && "Expected valid KnownBits");
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if (Known.isUnknown())
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return getFull(Known.getBitWidth());
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// For unsigned ranges, or signed ranges with known sign bit, create a simple
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// range between the smallest and largest possible value.
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if (!IsSigned || Known.isNegative() || Known.isNonNegative())
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return ConstantRange(Known.getMinValue(), Known.getMaxValue() + 1);
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// If we don't know the sign bit, pick the lower bound as a negative number
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// and the upper bound as a non-negative one.
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APInt Lower = Known.getMinValue(), Upper = Known.getMaxValue();
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Lower.setSignBit();
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Upper.clearSignBit();
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return ConstantRange(Lower, Upper + 1);
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}
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ConstantRange ConstantRange::makeAllowedICmpRegion(CmpInst::Predicate Pred,
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const ConstantRange &CR) {
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if (CR.isEmptySet())
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return CR;
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uint32_t W = CR.getBitWidth();
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switch (Pred) {
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default:
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llvm_unreachable("Invalid ICmp predicate to makeAllowedICmpRegion()");
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case CmpInst::ICMP_EQ:
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return CR;
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case CmpInst::ICMP_NE:
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if (CR.isSingleElement())
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return ConstantRange(CR.getUpper(), CR.getLower());
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return getFull(W);
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case CmpInst::ICMP_ULT: {
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APInt UMax(CR.getUnsignedMax());
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if (UMax.isMinValue())
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return getEmpty(W);
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return ConstantRange(APInt::getMinValue(W), std::move(UMax));
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}
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case CmpInst::ICMP_SLT: {
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APInt SMax(CR.getSignedMax());
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if (SMax.isMinSignedValue())
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return getEmpty(W);
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return ConstantRange(APInt::getSignedMinValue(W), std::move(SMax));
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}
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case CmpInst::ICMP_ULE:
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return getNonEmpty(APInt::getMinValue(W), CR.getUnsignedMax() + 1);
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case CmpInst::ICMP_SLE:
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return getNonEmpty(APInt::getSignedMinValue(W), CR.getSignedMax() + 1);
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case CmpInst::ICMP_UGT: {
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APInt UMin(CR.getUnsignedMin());
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if (UMin.isMaxValue())
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return getEmpty(W);
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return ConstantRange(std::move(UMin) + 1, APInt::getNullValue(W));
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}
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case CmpInst::ICMP_SGT: {
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APInt SMin(CR.getSignedMin());
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if (SMin.isMaxSignedValue())
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return getEmpty(W);
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return ConstantRange(std::move(SMin) + 1, APInt::getSignedMinValue(W));
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}
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case CmpInst::ICMP_UGE:
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return getNonEmpty(CR.getUnsignedMin(), APInt::getNullValue(W));
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case CmpInst::ICMP_SGE:
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return getNonEmpty(CR.getSignedMin(), APInt::getSignedMinValue(W));
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}
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}
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ConstantRange ConstantRange::makeSatisfyingICmpRegion(CmpInst::Predicate Pred,
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const ConstantRange &CR) {
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// Follows from De-Morgan's laws:
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//
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// ~(~A union ~B) == A intersect B.
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//
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return makeAllowedICmpRegion(CmpInst::getInversePredicate(Pred), CR)
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.inverse();
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}
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ConstantRange ConstantRange::makeExactICmpRegion(CmpInst::Predicate Pred,
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const APInt &C) {
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// Computes the exact range that is equal to both the constant ranges returned
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// by makeAllowedICmpRegion and makeSatisfyingICmpRegion. This is always true
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// when RHS is a singleton such as an APInt and so the assert is valid.
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// However for non-singleton RHS, for example ult [2,5) makeAllowedICmpRegion
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// returns [0,4) but makeSatisfyICmpRegion returns [0,2).
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//
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assert(makeAllowedICmpRegion(Pred, C) == makeSatisfyingICmpRegion(Pred, C));
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return makeAllowedICmpRegion(Pred, C);
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}
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bool ConstantRange::getEquivalentICmp(CmpInst::Predicate &Pred,
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APInt &RHS) const {
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bool Success = false;
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if (isFullSet() || isEmptySet()) {
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Pred = isEmptySet() ? CmpInst::ICMP_ULT : CmpInst::ICMP_UGE;
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RHS = APInt(getBitWidth(), 0);
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Success = true;
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} else if (auto *OnlyElt = getSingleElement()) {
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Pred = CmpInst::ICMP_EQ;
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RHS = *OnlyElt;
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Success = true;
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} else if (auto *OnlyMissingElt = getSingleMissingElement()) {
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Pred = CmpInst::ICMP_NE;
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RHS = *OnlyMissingElt;
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Success = true;
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} else if (getLower().isMinSignedValue() || getLower().isMinValue()) {
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Pred =
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getLower().isMinSignedValue() ? CmpInst::ICMP_SLT : CmpInst::ICMP_ULT;
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RHS = getUpper();
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Success = true;
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} else if (getUpper().isMinSignedValue() || getUpper().isMinValue()) {
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Pred =
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getUpper().isMinSignedValue() ? CmpInst::ICMP_SGE : CmpInst::ICMP_UGE;
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RHS = getLower();
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Success = true;
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}
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assert((!Success || ConstantRange::makeExactICmpRegion(Pred, RHS) == *this) &&
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"Bad result!");
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return Success;
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}
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bool ConstantRange::icmp(CmpInst::Predicate Pred,
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const ConstantRange &Other) const {
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return makeSatisfyingICmpRegion(Pred, Other).contains(*this);
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}
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/// Exact mul nuw region for single element RHS.
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static ConstantRange makeExactMulNUWRegion(const APInt &V) {
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unsigned BitWidth = V.getBitWidth();
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if (V == 0)
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return ConstantRange::getFull(V.getBitWidth());
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return ConstantRange::getNonEmpty(
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APIntOps::RoundingUDiv(APInt::getMinValue(BitWidth), V,
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APInt::Rounding::UP),
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APIntOps::RoundingUDiv(APInt::getMaxValue(BitWidth), V,
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APInt::Rounding::DOWN) + 1);
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}
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/// Exact mul nsw region for single element RHS.
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static ConstantRange makeExactMulNSWRegion(const APInt &V) {
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// Handle special case for 0, -1 and 1. See the last for reason why we
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// specialize -1 and 1.
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unsigned BitWidth = V.getBitWidth();
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if (V == 0 || V.isOneValue())
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return ConstantRange::getFull(BitWidth);
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APInt MinValue = APInt::getSignedMinValue(BitWidth);
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APInt MaxValue = APInt::getSignedMaxValue(BitWidth);
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// e.g. Returning [-127, 127], represented as [-127, -128).
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if (V.isAllOnesValue())
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return ConstantRange(-MaxValue, MinValue);
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APInt Lower, Upper;
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if (V.isNegative()) {
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Lower = APIntOps::RoundingSDiv(MaxValue, V, APInt::Rounding::UP);
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Upper = APIntOps::RoundingSDiv(MinValue, V, APInt::Rounding::DOWN);
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} else {
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Lower = APIntOps::RoundingSDiv(MinValue, V, APInt::Rounding::UP);
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Upper = APIntOps::RoundingSDiv(MaxValue, V, APInt::Rounding::DOWN);
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}
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// ConstantRange ctor take a half inclusive interval [Lower, Upper + 1).
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// Upper + 1 is guaranteed not to overflow, because |divisor| > 1. 0, -1,
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// and 1 are already handled as special cases.
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return ConstantRange(Lower, Upper + 1);
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}
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ConstantRange
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ConstantRange::makeGuaranteedNoWrapRegion(Instruction::BinaryOps BinOp,
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const ConstantRange &Other,
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unsigned NoWrapKind) {
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using OBO = OverflowingBinaryOperator;
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assert(Instruction::isBinaryOp(BinOp) && "Binary operators only!");
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assert((NoWrapKind == OBO::NoSignedWrap ||
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NoWrapKind == OBO::NoUnsignedWrap) &&
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"NoWrapKind invalid!");
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bool Unsigned = NoWrapKind == OBO::NoUnsignedWrap;
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unsigned BitWidth = Other.getBitWidth();
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switch (BinOp) {
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default:
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llvm_unreachable("Unsupported binary op");
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case Instruction::Add: {
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if (Unsigned)
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return getNonEmpty(APInt::getNullValue(BitWidth),
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-Other.getUnsignedMax());
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APInt SignedMinVal = APInt::getSignedMinValue(BitWidth);
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APInt SMin = Other.getSignedMin(), SMax = Other.getSignedMax();
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return getNonEmpty(
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SMin.isNegative() ? SignedMinVal - SMin : SignedMinVal,
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SMax.isStrictlyPositive() ? SignedMinVal - SMax : SignedMinVal);
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}
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case Instruction::Sub: {
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if (Unsigned)
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return getNonEmpty(Other.getUnsignedMax(), APInt::getMinValue(BitWidth));
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APInt SignedMinVal = APInt::getSignedMinValue(BitWidth);
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APInt SMin = Other.getSignedMin(), SMax = Other.getSignedMax();
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return getNonEmpty(
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SMax.isStrictlyPositive() ? SignedMinVal + SMax : SignedMinVal,
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SMin.isNegative() ? SignedMinVal + SMin : SignedMinVal);
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}
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case Instruction::Mul:
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if (Unsigned)
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return makeExactMulNUWRegion(Other.getUnsignedMax());
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return makeExactMulNSWRegion(Other.getSignedMin())
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.intersectWith(makeExactMulNSWRegion(Other.getSignedMax()));
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case Instruction::Shl: {
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// For given range of shift amounts, if we ignore all illegal shift amounts
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// (that always produce poison), what shift amount range is left?
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ConstantRange ShAmt = Other.intersectWith(
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ConstantRange(APInt(BitWidth, 0), APInt(BitWidth, (BitWidth - 1) + 1)));
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if (ShAmt.isEmptySet()) {
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// If the entire range of shift amounts is already poison-producing,
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// then we can freely add more poison-producing flags ontop of that.
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return getFull(BitWidth);
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}
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// There are some legal shift amounts, we can compute conservatively-correct
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// range of no-wrap inputs. Note that by now we have clamped the ShAmtUMax
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// to be at most bitwidth-1, which results in most conservative range.
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APInt ShAmtUMax = ShAmt.getUnsignedMax();
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if (Unsigned)
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return getNonEmpty(APInt::getNullValue(BitWidth),
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APInt::getMaxValue(BitWidth).lshr(ShAmtUMax) + 1);
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return getNonEmpty(APInt::getSignedMinValue(BitWidth).ashr(ShAmtUMax),
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APInt::getSignedMaxValue(BitWidth).ashr(ShAmtUMax) + 1);
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}
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}
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}
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ConstantRange ConstantRange::makeExactNoWrapRegion(Instruction::BinaryOps BinOp,
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const APInt &Other,
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unsigned NoWrapKind) {
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// makeGuaranteedNoWrapRegion() is exact for single-element ranges, as
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// "for all" and "for any" coincide in this case.
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return makeGuaranteedNoWrapRegion(BinOp, ConstantRange(Other), NoWrapKind);
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}
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bool ConstantRange::isFullSet() const {
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return Lower == Upper && Lower.isMaxValue();
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}
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bool ConstantRange::isEmptySet() const {
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return Lower == Upper && Lower.isMinValue();
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}
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bool ConstantRange::isWrappedSet() const {
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return Lower.ugt(Upper) && !Upper.isNullValue();
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}
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bool ConstantRange::isUpperWrapped() const {
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return Lower.ugt(Upper);
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}
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bool ConstantRange::isSignWrappedSet() const {
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return Lower.sgt(Upper) && !Upper.isMinSignedValue();
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}
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bool ConstantRange::isUpperSignWrapped() const {
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return Lower.sgt(Upper);
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}
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bool
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ConstantRange::isSizeStrictlySmallerThan(const ConstantRange &Other) const {
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assert(getBitWidth() == Other.getBitWidth());
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if (isFullSet())
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return false;
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if (Other.isFullSet())
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return true;
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return (Upper - Lower).ult(Other.Upper - Other.Lower);
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}
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bool
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ConstantRange::isSizeLargerThan(uint64_t MaxSize) const {
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assert(MaxSize && "MaxSize can't be 0.");
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// If this a full set, we need special handling to avoid needing an extra bit
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// to represent the size.
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if (isFullSet())
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return APInt::getMaxValue(getBitWidth()).ugt(MaxSize - 1);
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return (Upper - Lower).ugt(MaxSize);
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}
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bool ConstantRange::isAllNegative() const {
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// Empty set is all negative, full set is not.
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if (isEmptySet())
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return true;
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if (isFullSet())
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return false;
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return !isUpperSignWrapped() && !Upper.isStrictlyPositive();
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}
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bool ConstantRange::isAllNonNegative() const {
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// Empty and full set are automatically treated correctly.
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return !isSignWrappedSet() && Lower.isNonNegative();
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}
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APInt ConstantRange::getUnsignedMax() const {
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if (isFullSet() || isUpperWrapped())
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return APInt::getMaxValue(getBitWidth());
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return getUpper() - 1;
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}
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APInt ConstantRange::getUnsignedMin() const {
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if (isFullSet() || isWrappedSet())
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return APInt::getMinValue(getBitWidth());
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return getLower();
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}
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APInt ConstantRange::getSignedMax() const {
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if (isFullSet() || isUpperSignWrapped())
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return APInt::getSignedMaxValue(getBitWidth());
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return getUpper() - 1;
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}
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APInt ConstantRange::getSignedMin() const {
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if (isFullSet() || isSignWrappedSet())
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return APInt::getSignedMinValue(getBitWidth());
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return getLower();
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}
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bool ConstantRange::contains(const APInt &V) const {
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if (Lower == Upper)
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return isFullSet();
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if (!isUpperWrapped())
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return Lower.ule(V) && V.ult(Upper);
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return Lower.ule(V) || V.ult(Upper);
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}
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bool ConstantRange::contains(const ConstantRange &Other) const {
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if (isFullSet() || Other.isEmptySet()) return true;
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if (isEmptySet() || Other.isFullSet()) return false;
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if (!isUpperWrapped()) {
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if (Other.isUpperWrapped())
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return false;
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return Lower.ule(Other.getLower()) && Other.getUpper().ule(Upper);
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}
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if (!Other.isUpperWrapped())
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return Other.getUpper().ule(Upper) ||
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Lower.ule(Other.getLower());
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return Other.getUpper().ule(Upper) && Lower.ule(Other.getLower());
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}
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unsigned ConstantRange::getActiveBits() const {
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if (isEmptySet())
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return 0;
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return getUnsignedMax().getActiveBits();
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}
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unsigned ConstantRange::getMinSignedBits() const {
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if (isEmptySet())
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return 0;
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return std::max(getSignedMin().getMinSignedBits(),
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getSignedMax().getMinSignedBits());
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}
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ConstantRange ConstantRange::subtract(const APInt &Val) const {
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assert(Val.getBitWidth() == getBitWidth() && "Wrong bit width");
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// If the set is empty or full, don't modify the endpoints.
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if (Lower == Upper)
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return *this;
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return ConstantRange(Lower - Val, Upper - Val);
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}
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ConstantRange ConstantRange::difference(const ConstantRange &CR) const {
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return intersectWith(CR.inverse());
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}
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static ConstantRange getPreferredRange(
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const ConstantRange &CR1, const ConstantRange &CR2,
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ConstantRange::PreferredRangeType Type) {
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if (Type == ConstantRange::Unsigned) {
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if (!CR1.isWrappedSet() && CR2.isWrappedSet())
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return CR1;
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if (CR1.isWrappedSet() && !CR2.isWrappedSet())
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return CR2;
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} else if (Type == ConstantRange::Signed) {
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if (!CR1.isSignWrappedSet() && CR2.isSignWrappedSet())
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return CR1;
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if (CR1.isSignWrappedSet() && !CR2.isSignWrappedSet())
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return CR2;
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}
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if (CR1.isSizeStrictlySmallerThan(CR2))
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return CR1;
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return CR2;
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}
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ConstantRange ConstantRange::intersectWith(const ConstantRange &CR,
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PreferredRangeType Type) const {
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assert(getBitWidth() == CR.getBitWidth() &&
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"ConstantRange types don't agree!");
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// Handle common cases.
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if ( isEmptySet() || CR.isFullSet()) return *this;
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|
if (CR.isEmptySet() || isFullSet()) return CR;
|
|
|
|
if (!isUpperWrapped() && CR.isUpperWrapped())
|
|
return CR.intersectWith(*this, Type);
|
|
|
|
if (!isUpperWrapped() && !CR.isUpperWrapped()) {
|
|
if (Lower.ult(CR.Lower)) {
|
|
// L---U : this
|
|
// L---U : CR
|
|
if (Upper.ule(CR.Lower))
|
|
return getEmpty();
|
|
|
|
// L---U : this
|
|
// L---U : CR
|
|
if (Upper.ult(CR.Upper))
|
|
return ConstantRange(CR.Lower, Upper);
|
|
|
|
// L-------U : this
|
|
// L---U : CR
|
|
return CR;
|
|
}
|
|
// L---U : this
|
|
// L-------U : CR
|
|
if (Upper.ult(CR.Upper))
|
|
return *this;
|
|
|
|
// L-----U : this
|
|
// L-----U : CR
|
|
if (Lower.ult(CR.Upper))
|
|
return ConstantRange(Lower, CR.Upper);
|
|
|
|
// L---U : this
|
|
// L---U : CR
|
|
return getEmpty();
|
|
}
|
|
|
|
if (isUpperWrapped() && !CR.isUpperWrapped()) {
|
|
if (CR.Lower.ult(Upper)) {
|
|
// ------U L--- : this
|
|
// L--U : CR
|
|
if (CR.Upper.ult(Upper))
|
|
return CR;
|
|
|
|
// ------U L--- : this
|
|
// L------U : CR
|
|
if (CR.Upper.ule(Lower))
|
|
return ConstantRange(CR.Lower, Upper);
|
|
|
|
// ------U L--- : this
|
|
// L----------U : CR
|
|
return getPreferredRange(*this, CR, Type);
|
|
}
|
|
if (CR.Lower.ult(Lower)) {
|
|
// --U L---- : this
|
|
// L--U : CR
|
|
if (CR.Upper.ule(Lower))
|
|
return getEmpty();
|
|
|
|
// --U L---- : this
|
|
// L------U : CR
|
|
return ConstantRange(Lower, CR.Upper);
|
|
}
|
|
|
|
// --U L------ : this
|
|
// L--U : CR
|
|
return CR;
|
|
}
|
|
|
|
if (CR.Upper.ult(Upper)) {
|
|
// ------U L-- : this
|
|
// --U L------ : CR
|
|
if (CR.Lower.ult(Upper))
|
|
return getPreferredRange(*this, CR, Type);
|
|
|
|
// ----U L-- : this
|
|
// --U L---- : CR
|
|
if (CR.Lower.ult(Lower))
|
|
return ConstantRange(Lower, CR.Upper);
|
|
|
|
// ----U L---- : this
|
|
// --U L-- : CR
|
|
return CR;
|
|
}
|
|
if (CR.Upper.ule(Lower)) {
|
|
// --U L-- : this
|
|
// ----U L---- : CR
|
|
if (CR.Lower.ult(Lower))
|
|
return *this;
|
|
|
|
// --U L---- : this
|
|
// ----U L-- : CR
|
|
return ConstantRange(CR.Lower, Upper);
|
|
}
|
|
|
|
// --U L------ : this
|
|
// ------U L-- : CR
|
|
return getPreferredRange(*this, CR, Type);
|
|
}
|
|
|
|
ConstantRange ConstantRange::unionWith(const ConstantRange &CR,
|
|
PreferredRangeType Type) const {
|
|
assert(getBitWidth() == CR.getBitWidth() &&
|
|
"ConstantRange types don't agree!");
|
|
|
|
if ( isFullSet() || CR.isEmptySet()) return *this;
|
|
if (CR.isFullSet() || isEmptySet()) return CR;
|
|
|
|
if (!isUpperWrapped() && CR.isUpperWrapped())
|
|
return CR.unionWith(*this, Type);
|
|
|
|
if (!isUpperWrapped() && !CR.isUpperWrapped()) {
|
|
// L---U and L---U : this
|
|
// L---U L---U : CR
|
|
// result in one of
|
|
// L---------U
|
|
// -----U L-----
|
|
if (CR.Upper.ult(Lower) || Upper.ult(CR.Lower))
|
|
return getPreferredRange(
|
|
ConstantRange(Lower, CR.Upper), ConstantRange(CR.Lower, Upper), Type);
|
|
|
|
APInt L = CR.Lower.ult(Lower) ? CR.Lower : Lower;
|
|
APInt U = (CR.Upper - 1).ugt(Upper - 1) ? CR.Upper : Upper;
|
|
|
|
if (L.isNullValue() && U.isNullValue())
|
|
return getFull();
|
|
|
|
return ConstantRange(std::move(L), std::move(U));
|
|
}
|
|
|
|
if (!CR.isUpperWrapped()) {
|
|
// ------U L----- and ------U L----- : this
|
|
// L--U L--U : CR
|
|
if (CR.Upper.ule(Upper) || CR.Lower.uge(Lower))
|
|
return *this;
|
|
|
|
// ------U L----- : this
|
|
// L---------U : CR
|
|
if (CR.Lower.ule(Upper) && Lower.ule(CR.Upper))
|
|
return getFull();
|
|
|
|
// ----U L---- : this
|
|
// L---U : CR
|
|
// results in one of
|
|
// ----------U L----
|
|
// ----U L----------
|
|
if (Upper.ult(CR.Lower) && CR.Upper.ult(Lower))
|
|
return getPreferredRange(
|
|
ConstantRange(Lower, CR.Upper), ConstantRange(CR.Lower, Upper), Type);
|
|
|
|
// ----U L----- : this
|
|
// L----U : CR
|
|
if (Upper.ult(CR.Lower) && Lower.ule(CR.Upper))
|
|
return ConstantRange(CR.Lower, Upper);
|
|
|
|
// ------U L---- : this
|
|
// L-----U : CR
|
|
assert(CR.Lower.ule(Upper) && CR.Upper.ult(Lower) &&
|
|
"ConstantRange::unionWith missed a case with one range wrapped");
|
|
return ConstantRange(Lower, CR.Upper);
|
|
}
|
|
|
|
// ------U L---- and ------U L---- : this
|
|
// -U L----------- and ------------U L : CR
|
|
if (CR.Lower.ule(Upper) || Lower.ule(CR.Upper))
|
|
return getFull();
|
|
|
|
APInt L = CR.Lower.ult(Lower) ? CR.Lower : Lower;
|
|
APInt U = CR.Upper.ugt(Upper) ? CR.Upper : Upper;
|
|
|
|
return ConstantRange(std::move(L), std::move(U));
|
|
}
|
|
|
|
ConstantRange ConstantRange::castOp(Instruction::CastOps CastOp,
|
|
uint32_t ResultBitWidth) const {
|
|
switch (CastOp) {
|
|
default:
|
|
llvm_unreachable("unsupported cast type");
|
|
case Instruction::Trunc:
|
|
return truncate(ResultBitWidth);
|
|
case Instruction::SExt:
|
|
return signExtend(ResultBitWidth);
|
|
case Instruction::ZExt:
|
|
return zeroExtend(ResultBitWidth);
|
|
case Instruction::BitCast:
|
|
return *this;
|
|
case Instruction::FPToUI:
|
|
case Instruction::FPToSI:
|
|
if (getBitWidth() == ResultBitWidth)
|
|
return *this;
|
|
else
|
|
return getFull(ResultBitWidth);
|
|
case Instruction::UIToFP: {
|
|
// TODO: use input range if available
|
|
auto BW = getBitWidth();
|
|
APInt Min = APInt::getMinValue(BW).zextOrSelf(ResultBitWidth);
|
|
APInt Max = APInt::getMaxValue(BW).zextOrSelf(ResultBitWidth);
|
|
return ConstantRange(std::move(Min), std::move(Max));
|
|
}
|
|
case Instruction::SIToFP: {
|
|
// TODO: use input range if available
|
|
auto BW = getBitWidth();
|
|
APInt SMin = APInt::getSignedMinValue(BW).sextOrSelf(ResultBitWidth);
|
|
APInt SMax = APInt::getSignedMaxValue(BW).sextOrSelf(ResultBitWidth);
|
|
return ConstantRange(std::move(SMin), std::move(SMax));
|
|
}
|
|
case Instruction::FPTrunc:
|
|
case Instruction::FPExt:
|
|
case Instruction::IntToPtr:
|
|
case Instruction::PtrToInt:
|
|
case Instruction::AddrSpaceCast:
|
|
// Conservatively return getFull set.
|
|
return getFull(ResultBitWidth);
|
|
};
|
|
}
|
|
|
|
ConstantRange ConstantRange::zeroExtend(uint32_t DstTySize) const {
|
|
if (isEmptySet()) return getEmpty(DstTySize);
|
|
|
|
unsigned SrcTySize = getBitWidth();
|
|
assert(SrcTySize < DstTySize && "Not a value extension");
|
|
if (isFullSet() || isUpperWrapped()) {
|
|
// Change into [0, 1 << src bit width)
|
|
APInt LowerExt(DstTySize, 0);
|
|
if (!Upper) // special case: [X, 0) -- not really wrapping around
|
|
LowerExt = Lower.zext(DstTySize);
|
|
return ConstantRange(std::move(LowerExt),
|
|
APInt::getOneBitSet(DstTySize, SrcTySize));
|
|
}
|
|
|
|
return ConstantRange(Lower.zext(DstTySize), Upper.zext(DstTySize));
|
|
}
|
|
|
|
ConstantRange ConstantRange::signExtend(uint32_t DstTySize) const {
|
|
if (isEmptySet()) return getEmpty(DstTySize);
|
|
|
|
unsigned SrcTySize = getBitWidth();
|
|
assert(SrcTySize < DstTySize && "Not a value extension");
|
|
|
|
// special case: [X, INT_MIN) -- not really wrapping around
|
|
if (Upper.isMinSignedValue())
|
|
return ConstantRange(Lower.sext(DstTySize), Upper.zext(DstTySize));
|
|
|
|
if (isFullSet() || isSignWrappedSet()) {
|
|
return ConstantRange(APInt::getHighBitsSet(DstTySize,DstTySize-SrcTySize+1),
|
|
APInt::getLowBitsSet(DstTySize, SrcTySize-1) + 1);
|
|
}
|
|
|
|
return ConstantRange(Lower.sext(DstTySize), Upper.sext(DstTySize));
|
|
}
|
|
|
|
ConstantRange ConstantRange::truncate(uint32_t DstTySize) const {
|
|
assert(getBitWidth() > DstTySize && "Not a value truncation");
|
|
if (isEmptySet())
|
|
return getEmpty(DstTySize);
|
|
if (isFullSet())
|
|
return getFull(DstTySize);
|
|
|
|
APInt LowerDiv(Lower), UpperDiv(Upper);
|
|
ConstantRange Union(DstTySize, /*isFullSet=*/false);
|
|
|
|
// Analyze wrapped sets in their two parts: [0, Upper) \/ [Lower, MaxValue]
|
|
// We use the non-wrapped set code to analyze the [Lower, MaxValue) part, and
|
|
// then we do the union with [MaxValue, Upper)
|
|
if (isUpperWrapped()) {
|
|
// If Upper is greater than or equal to MaxValue(DstTy), it covers the whole
|
|
// truncated range.
|
|
if (Upper.getActiveBits() > DstTySize ||
|
|
Upper.countTrailingOnes() == DstTySize)
|
|
return getFull(DstTySize);
|
|
|
|
Union = ConstantRange(APInt::getMaxValue(DstTySize),Upper.trunc(DstTySize));
|
|
UpperDiv.setAllBits();
|
|
|
|
// Union covers the MaxValue case, so return if the remaining range is just
|
|
// MaxValue(DstTy).
|
|
if (LowerDiv == UpperDiv)
|
|
return Union;
|
|
}
|
|
|
|
// Chop off the most significant bits that are past the destination bitwidth.
|
|
if (LowerDiv.getActiveBits() > DstTySize) {
|
|
// Mask to just the signficant bits and subtract from LowerDiv/UpperDiv.
|
|
APInt Adjust = LowerDiv & APInt::getBitsSetFrom(getBitWidth(), DstTySize);
|
|
LowerDiv -= Adjust;
|
|
UpperDiv -= Adjust;
|
|
}
|
|
|
|
unsigned UpperDivWidth = UpperDiv.getActiveBits();
|
|
if (UpperDivWidth <= DstTySize)
|
|
return ConstantRange(LowerDiv.trunc(DstTySize),
|
|
UpperDiv.trunc(DstTySize)).unionWith(Union);
|
|
|
|
// The truncated value wraps around. Check if we can do better than fullset.
|
|
if (UpperDivWidth == DstTySize + 1) {
|
|
// Clear the MSB so that UpperDiv wraps around.
|
|
UpperDiv.clearBit(DstTySize);
|
|
if (UpperDiv.ult(LowerDiv))
|
|
return ConstantRange(LowerDiv.trunc(DstTySize),
|
|
UpperDiv.trunc(DstTySize)).unionWith(Union);
|
|
}
|
|
|
|
return getFull(DstTySize);
|
|
}
|
|
|
|
ConstantRange ConstantRange::zextOrTrunc(uint32_t DstTySize) const {
|
|
unsigned SrcTySize = getBitWidth();
|
|
if (SrcTySize > DstTySize)
|
|
return truncate(DstTySize);
|
|
if (SrcTySize < DstTySize)
|
|
return zeroExtend(DstTySize);
|
|
return *this;
|
|
}
|
|
|
|
ConstantRange ConstantRange::sextOrTrunc(uint32_t DstTySize) const {
|
|
unsigned SrcTySize = getBitWidth();
|
|
if (SrcTySize > DstTySize)
|
|
return truncate(DstTySize);
|
|
if (SrcTySize < DstTySize)
|
|
return signExtend(DstTySize);
|
|
return *this;
|
|
}
|
|
|
|
ConstantRange ConstantRange::binaryOp(Instruction::BinaryOps BinOp,
|
|
const ConstantRange &Other) const {
|
|
assert(Instruction::isBinaryOp(BinOp) && "Binary operators only!");
|
|
|
|
switch (BinOp) {
|
|
case Instruction::Add:
|
|
return add(Other);
|
|
case Instruction::Sub:
|
|
return sub(Other);
|
|
case Instruction::Mul:
|
|
return multiply(Other);
|
|
case Instruction::UDiv:
|
|
return udiv(Other);
|
|
case Instruction::SDiv:
|
|
return sdiv(Other);
|
|
case Instruction::URem:
|
|
return urem(Other);
|
|
case Instruction::SRem:
|
|
return srem(Other);
|
|
case Instruction::Shl:
|
|
return shl(Other);
|
|
case Instruction::LShr:
|
|
return lshr(Other);
|
|
case Instruction::AShr:
|
|
return ashr(Other);
|
|
case Instruction::And:
|
|
return binaryAnd(Other);
|
|
case Instruction::Or:
|
|
return binaryOr(Other);
|
|
case Instruction::Xor:
|
|
return binaryXor(Other);
|
|
// Note: floating point operations applied to abstract ranges are just
|
|
// ideal integer operations with a lossy representation
|
|
case Instruction::FAdd:
|
|
return add(Other);
|
|
case Instruction::FSub:
|
|
return sub(Other);
|
|
case Instruction::FMul:
|
|
return multiply(Other);
|
|
default:
|
|
// Conservatively return getFull set.
|
|
return getFull();
|
|
}
|
|
}
|
|
|
|
ConstantRange ConstantRange::overflowingBinaryOp(Instruction::BinaryOps BinOp,
|
|
const ConstantRange &Other,
|
|
unsigned NoWrapKind) const {
|
|
assert(Instruction::isBinaryOp(BinOp) && "Binary operators only!");
|
|
|
|
switch (BinOp) {
|
|
case Instruction::Add:
|
|
return addWithNoWrap(Other, NoWrapKind);
|
|
case Instruction::Sub:
|
|
return subWithNoWrap(Other, NoWrapKind);
|
|
default:
|
|
// Don't know about this Overflowing Binary Operation.
|
|
// Conservatively fallback to plain binop handling.
|
|
return binaryOp(BinOp, Other);
|
|
}
|
|
}
|
|
|
|
bool ConstantRange::isIntrinsicSupported(Intrinsic::ID IntrinsicID) {
|
|
switch (IntrinsicID) {
|
|
case Intrinsic::uadd_sat:
|
|
case Intrinsic::usub_sat:
|
|
case Intrinsic::sadd_sat:
|
|
case Intrinsic::ssub_sat:
|
|
case Intrinsic::umin:
|
|
case Intrinsic::umax:
|
|
case Intrinsic::smin:
|
|
case Intrinsic::smax:
|
|
case Intrinsic::abs:
|
|
return true;
|
|
default:
|
|
return false;
|
|
}
|
|
}
|
|
|
|
ConstantRange ConstantRange::intrinsic(Intrinsic::ID IntrinsicID,
|
|
ArrayRef<ConstantRange> Ops) {
|
|
switch (IntrinsicID) {
|
|
case Intrinsic::uadd_sat:
|
|
return Ops[0].uadd_sat(Ops[1]);
|
|
case Intrinsic::usub_sat:
|
|
return Ops[0].usub_sat(Ops[1]);
|
|
case Intrinsic::sadd_sat:
|
|
return Ops[0].sadd_sat(Ops[1]);
|
|
case Intrinsic::ssub_sat:
|
|
return Ops[0].ssub_sat(Ops[1]);
|
|
case Intrinsic::umin:
|
|
return Ops[0].umin(Ops[1]);
|
|
case Intrinsic::umax:
|
|
return Ops[0].umax(Ops[1]);
|
|
case Intrinsic::smin:
|
|
return Ops[0].smin(Ops[1]);
|
|
case Intrinsic::smax:
|
|
return Ops[0].smax(Ops[1]);
|
|
case Intrinsic::abs: {
|
|
const APInt *IntMinIsPoison = Ops[1].getSingleElement();
|
|
assert(IntMinIsPoison && "Must be known (immarg)");
|
|
assert(IntMinIsPoison->getBitWidth() == 1 && "Must be boolean");
|
|
return Ops[0].abs(IntMinIsPoison->getBoolValue());
|
|
}
|
|
default:
|
|
assert(!isIntrinsicSupported(IntrinsicID) && "Shouldn't be supported");
|
|
llvm_unreachable("Unsupported intrinsic");
|
|
}
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::add(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
if (isFullSet() || Other.isFullSet())
|
|
return getFull();
|
|
|
|
APInt NewLower = getLower() + Other.getLower();
|
|
APInt NewUpper = getUpper() + Other.getUpper() - 1;
|
|
if (NewLower == NewUpper)
|
|
return getFull();
|
|
|
|
ConstantRange X = ConstantRange(std::move(NewLower), std::move(NewUpper));
|
|
if (X.isSizeStrictlySmallerThan(*this) ||
|
|
X.isSizeStrictlySmallerThan(Other))
|
|
// We've wrapped, therefore, full set.
|
|
return getFull();
|
|
return X;
|
|
}
|
|
|
|
ConstantRange ConstantRange::addWithNoWrap(const ConstantRange &Other,
|
|
unsigned NoWrapKind,
|
|
PreferredRangeType RangeType) const {
|
|
// Calculate the range for "X + Y" which is guaranteed not to wrap(overflow).
|
|
// (X is from this, and Y is from Other)
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
if (isFullSet() && Other.isFullSet())
|
|
return getFull();
|
|
|
|
using OBO = OverflowingBinaryOperator;
|
|
ConstantRange Result = add(Other);
|
|
|
|
// If an overflow happens for every value pair in these two constant ranges,
|
|
// we must return Empty set. In this case, we get that for free, because we
|
|
// get lucky that intersection of add() with uadd_sat()/sadd_sat() results
|
|
// in an empty set.
|
|
|
|
if (NoWrapKind & OBO::NoSignedWrap)
|
|
Result = Result.intersectWith(sadd_sat(Other), RangeType);
|
|
|
|
if (NoWrapKind & OBO::NoUnsignedWrap)
|
|
Result = Result.intersectWith(uadd_sat(Other), RangeType);
|
|
|
|
return Result;
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::sub(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
if (isFullSet() || Other.isFullSet())
|
|
return getFull();
|
|
|
|
APInt NewLower = getLower() - Other.getUpper() + 1;
|
|
APInt NewUpper = getUpper() - Other.getLower();
|
|
if (NewLower == NewUpper)
|
|
return getFull();
|
|
|
|
ConstantRange X = ConstantRange(std::move(NewLower), std::move(NewUpper));
|
|
if (X.isSizeStrictlySmallerThan(*this) ||
|
|
X.isSizeStrictlySmallerThan(Other))
|
|
// We've wrapped, therefore, full set.
|
|
return getFull();
|
|
return X;
|
|
}
|
|
|
|
ConstantRange ConstantRange::subWithNoWrap(const ConstantRange &Other,
|
|
unsigned NoWrapKind,
|
|
PreferredRangeType RangeType) const {
|
|
// Calculate the range for "X - Y" which is guaranteed not to wrap(overflow).
|
|
// (X is from this, and Y is from Other)
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
if (isFullSet() && Other.isFullSet())
|
|
return getFull();
|
|
|
|
using OBO = OverflowingBinaryOperator;
|
|
ConstantRange Result = sub(Other);
|
|
|
|
// If an overflow happens for every value pair in these two constant ranges,
|
|
// we must return Empty set. In signed case, we get that for free, because we
|
|
// get lucky that intersection of sub() with ssub_sat() results in an
|
|
// empty set. But for unsigned we must perform the overflow check manually.
|
|
|
|
if (NoWrapKind & OBO::NoSignedWrap)
|
|
Result = Result.intersectWith(ssub_sat(Other), RangeType);
|
|
|
|
if (NoWrapKind & OBO::NoUnsignedWrap) {
|
|
if (getUnsignedMax().ult(Other.getUnsignedMin()))
|
|
return getEmpty(); // Always overflows.
|
|
Result = Result.intersectWith(usub_sat(Other), RangeType);
|
|
}
|
|
|
|
return Result;
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::multiply(const ConstantRange &Other) const {
|
|
// TODO: If either operand is a single element and the multiply is known to
|
|
// be non-wrapping, round the result min and max value to the appropriate
|
|
// multiple of that element. If wrapping is possible, at least adjust the
|
|
// range according to the greatest power-of-two factor of the single element.
|
|
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
|
|
// Multiplication is signedness-independent. However different ranges can be
|
|
// obtained depending on how the input ranges are treated. These different
|
|
// ranges are all conservatively correct, but one might be better than the
|
|
// other. We calculate two ranges; one treating the inputs as unsigned
|
|
// and the other signed, then return the smallest of these ranges.
|
|
|
|
// Unsigned range first.
|
|
APInt this_min = getUnsignedMin().zext(getBitWidth() * 2);
|
|
APInt this_max = getUnsignedMax().zext(getBitWidth() * 2);
|
|
APInt Other_min = Other.getUnsignedMin().zext(getBitWidth() * 2);
|
|
APInt Other_max = Other.getUnsignedMax().zext(getBitWidth() * 2);
|
|
|
|
ConstantRange Result_zext = ConstantRange(this_min * Other_min,
|
|
this_max * Other_max + 1);
|
|
ConstantRange UR = Result_zext.truncate(getBitWidth());
|
|
|
|
// If the unsigned range doesn't wrap, and isn't negative then it's a range
|
|
// from one positive number to another which is as good as we can generate.
|
|
// In this case, skip the extra work of generating signed ranges which aren't
|
|
// going to be better than this range.
|
|
if (!UR.isUpperWrapped() &&
|
|
(UR.getUpper().isNonNegative() || UR.getUpper().isMinSignedValue()))
|
|
return UR;
|
|
|
|
// Now the signed range. Because we could be dealing with negative numbers
|
|
// here, the lower bound is the smallest of the cartesian product of the
|
|
// lower and upper ranges; for example:
|
|
// [-1,4) * [-2,3) = min(-1*-2, -1*2, 3*-2, 3*2) = -6.
|
|
// Similarly for the upper bound, swapping min for max.
|
|
|
|
this_min = getSignedMin().sext(getBitWidth() * 2);
|
|
this_max = getSignedMax().sext(getBitWidth() * 2);
|
|
Other_min = Other.getSignedMin().sext(getBitWidth() * 2);
|
|
Other_max = Other.getSignedMax().sext(getBitWidth() * 2);
|
|
|
|
auto L = {this_min * Other_min, this_min * Other_max,
|
|
this_max * Other_min, this_max * Other_max};
|
|
auto Compare = [](const APInt &A, const APInt &B) { return A.slt(B); };
|
|
ConstantRange Result_sext(std::min(L, Compare), std::max(L, Compare) + 1);
|
|
ConstantRange SR = Result_sext.truncate(getBitWidth());
|
|
|
|
return UR.isSizeStrictlySmallerThan(SR) ? UR : SR;
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::smax(const ConstantRange &Other) const {
|
|
// X smax Y is: range(smax(X_smin, Y_smin),
|
|
// smax(X_smax, Y_smax))
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
APInt NewL = APIntOps::smax(getSignedMin(), Other.getSignedMin());
|
|
APInt NewU = APIntOps::smax(getSignedMax(), Other.getSignedMax()) + 1;
|
|
ConstantRange Res = getNonEmpty(std::move(NewL), std::move(NewU));
|
|
if (isSignWrappedSet() || Other.isSignWrappedSet())
|
|
return Res.intersectWith(unionWith(Other, Signed), Signed);
|
|
return Res;
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::umax(const ConstantRange &Other) const {
|
|
// X umax Y is: range(umax(X_umin, Y_umin),
|
|
// umax(X_umax, Y_umax))
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
APInt NewL = APIntOps::umax(getUnsignedMin(), Other.getUnsignedMin());
|
|
APInt NewU = APIntOps::umax(getUnsignedMax(), Other.getUnsignedMax()) + 1;
|
|
ConstantRange Res = getNonEmpty(std::move(NewL), std::move(NewU));
|
|
if (isWrappedSet() || Other.isWrappedSet())
|
|
return Res.intersectWith(unionWith(Other, Unsigned), Unsigned);
|
|
return Res;
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::smin(const ConstantRange &Other) const {
|
|
// X smin Y is: range(smin(X_smin, Y_smin),
|
|
// smin(X_smax, Y_smax))
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
APInt NewL = APIntOps::smin(getSignedMin(), Other.getSignedMin());
|
|
APInt NewU = APIntOps::smin(getSignedMax(), Other.getSignedMax()) + 1;
|
|
ConstantRange Res = getNonEmpty(std::move(NewL), std::move(NewU));
|
|
if (isSignWrappedSet() || Other.isSignWrappedSet())
|
|
return Res.intersectWith(unionWith(Other, Signed), Signed);
|
|
return Res;
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::umin(const ConstantRange &Other) const {
|
|
// X umin Y is: range(umin(X_umin, Y_umin),
|
|
// umin(X_umax, Y_umax))
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
APInt NewL = APIntOps::umin(getUnsignedMin(), Other.getUnsignedMin());
|
|
APInt NewU = APIntOps::umin(getUnsignedMax(), Other.getUnsignedMax()) + 1;
|
|
ConstantRange Res = getNonEmpty(std::move(NewL), std::move(NewU));
|
|
if (isWrappedSet() || Other.isWrappedSet())
|
|
return Res.intersectWith(unionWith(Other, Unsigned), Unsigned);
|
|
return Res;
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::udiv(const ConstantRange &RHS) const {
|
|
if (isEmptySet() || RHS.isEmptySet() || RHS.getUnsignedMax().isNullValue())
|
|
return getEmpty();
|
|
|
|
APInt Lower = getUnsignedMin().udiv(RHS.getUnsignedMax());
|
|
|
|
APInt RHS_umin = RHS.getUnsignedMin();
|
|
if (RHS_umin.isNullValue()) {
|
|
// We want the lowest value in RHS excluding zero. Usually that would be 1
|
|
// except for a range in the form of [X, 1) in which case it would be X.
|
|
if (RHS.getUpper() == 1)
|
|
RHS_umin = RHS.getLower();
|
|
else
|
|
RHS_umin = 1;
|
|
}
|
|
|
|
APInt Upper = getUnsignedMax().udiv(RHS_umin) + 1;
|
|
return getNonEmpty(std::move(Lower), std::move(Upper));
|
|
}
|
|
|
|
ConstantRange ConstantRange::sdiv(const ConstantRange &RHS) const {
|
|
// We split up the LHS and RHS into positive and negative components
|
|
// and then also compute the positive and negative components of the result
|
|
// separately by combining division results with the appropriate signs.
|
|
APInt Zero = APInt::getNullValue(getBitWidth());
|
|
APInt SignedMin = APInt::getSignedMinValue(getBitWidth());
|
|
ConstantRange PosFilter(APInt(getBitWidth(), 1), SignedMin);
|
|
ConstantRange NegFilter(SignedMin, Zero);
|
|
ConstantRange PosL = intersectWith(PosFilter);
|
|
ConstantRange NegL = intersectWith(NegFilter);
|
|
ConstantRange PosR = RHS.intersectWith(PosFilter);
|
|
ConstantRange NegR = RHS.intersectWith(NegFilter);
|
|
|
|
ConstantRange PosRes = getEmpty();
|
|
if (!PosL.isEmptySet() && !PosR.isEmptySet())
|
|
// pos / pos = pos.
|
|
PosRes = ConstantRange(PosL.Lower.sdiv(PosR.Upper - 1),
|
|
(PosL.Upper - 1).sdiv(PosR.Lower) + 1);
|
|
|
|
if (!NegL.isEmptySet() && !NegR.isEmptySet()) {
|
|
// neg / neg = pos.
|
|
//
|
|
// We need to deal with one tricky case here: SignedMin / -1 is UB on the
|
|
// IR level, so we'll want to exclude this case when calculating bounds.
|
|
// (For APInts the operation is well-defined and yields SignedMin.) We
|
|
// handle this by dropping either SignedMin from the LHS or -1 from the RHS.
|
|
APInt Lo = (NegL.Upper - 1).sdiv(NegR.Lower);
|
|
if (NegL.Lower.isMinSignedValue() && NegR.Upper.isNullValue()) {
|
|
// Remove -1 from the LHS. Skip if it's the only element, as this would
|
|
// leave us with an empty set.
|
|
if (!NegR.Lower.isAllOnesValue()) {
|
|
APInt AdjNegRUpper;
|
|
if (RHS.Lower.isAllOnesValue())
|
|
// Negative part of [-1, X] without -1 is [SignedMin, X].
|
|
AdjNegRUpper = RHS.Upper;
|
|
else
|
|
// [X, -1] without -1 is [X, -2].
|
|
AdjNegRUpper = NegR.Upper - 1;
|
|
|
|
PosRes = PosRes.unionWith(
|
|
ConstantRange(Lo, NegL.Lower.sdiv(AdjNegRUpper - 1) + 1));
|
|
}
|
|
|
|
// Remove SignedMin from the RHS. Skip if it's the only element, as this
|
|
// would leave us with an empty set.
|
|
if (NegL.Upper != SignedMin + 1) {
|
|
APInt AdjNegLLower;
|
|
if (Upper == SignedMin + 1)
|
|
// Negative part of [X, SignedMin] without SignedMin is [X, -1].
|
|
AdjNegLLower = Lower;
|
|
else
|
|
// [SignedMin, X] without SignedMin is [SignedMin + 1, X].
|
|
AdjNegLLower = NegL.Lower + 1;
|
|
|
|
PosRes = PosRes.unionWith(
|
|
ConstantRange(std::move(Lo),
|
|
AdjNegLLower.sdiv(NegR.Upper - 1) + 1));
|
|
}
|
|
} else {
|
|
PosRes = PosRes.unionWith(
|
|
ConstantRange(std::move(Lo), NegL.Lower.sdiv(NegR.Upper - 1) + 1));
|
|
}
|
|
}
|
|
|
|
ConstantRange NegRes = getEmpty();
|
|
if (!PosL.isEmptySet() && !NegR.isEmptySet())
|
|
// pos / neg = neg.
|
|
NegRes = ConstantRange((PosL.Upper - 1).sdiv(NegR.Upper - 1),
|
|
PosL.Lower.sdiv(NegR.Lower) + 1);
|
|
|
|
if (!NegL.isEmptySet() && !PosR.isEmptySet())
|
|
// neg / pos = neg.
|
|
NegRes = NegRes.unionWith(
|
|
ConstantRange(NegL.Lower.sdiv(PosR.Lower),
|
|
(NegL.Upper - 1).sdiv(PosR.Upper - 1) + 1));
|
|
|
|
// Prefer a non-wrapping signed range here.
|
|
ConstantRange Res = NegRes.unionWith(PosRes, PreferredRangeType::Signed);
|
|
|
|
// Preserve the zero that we dropped when splitting the LHS by sign.
|
|
if (contains(Zero) && (!PosR.isEmptySet() || !NegR.isEmptySet()))
|
|
Res = Res.unionWith(ConstantRange(Zero));
|
|
return Res;
|
|
}
|
|
|
|
ConstantRange ConstantRange::urem(const ConstantRange &RHS) const {
|
|
if (isEmptySet() || RHS.isEmptySet() || RHS.getUnsignedMax().isNullValue())
|
|
return getEmpty();
|
|
|
|
// L % R for L < R is L.
|
|
if (getUnsignedMax().ult(RHS.getUnsignedMin()))
|
|
return *this;
|
|
|
|
// L % R is <= L and < R.
|
|
APInt Upper = APIntOps::umin(getUnsignedMax(), RHS.getUnsignedMax() - 1) + 1;
|
|
return getNonEmpty(APInt::getNullValue(getBitWidth()), std::move(Upper));
|
|
}
|
|
|
|
ConstantRange ConstantRange::srem(const ConstantRange &RHS) const {
|
|
if (isEmptySet() || RHS.isEmptySet())
|
|
return getEmpty();
|
|
|
|
ConstantRange AbsRHS = RHS.abs();
|
|
APInt MinAbsRHS = AbsRHS.getUnsignedMin();
|
|
APInt MaxAbsRHS = AbsRHS.getUnsignedMax();
|
|
|
|
// Modulus by zero is UB.
|
|
if (MaxAbsRHS.isNullValue())
|
|
return getEmpty();
|
|
|
|
if (MinAbsRHS.isNullValue())
|
|
++MinAbsRHS;
|
|
|
|
APInt MinLHS = getSignedMin(), MaxLHS = getSignedMax();
|
|
|
|
if (MinLHS.isNonNegative()) {
|
|
// L % R for L < R is L.
|
|
if (MaxLHS.ult(MinAbsRHS))
|
|
return *this;
|
|
|
|
// L % R is <= L and < R.
|
|
APInt Upper = APIntOps::umin(MaxLHS, MaxAbsRHS - 1) + 1;
|
|
return ConstantRange(APInt::getNullValue(getBitWidth()), std::move(Upper));
|
|
}
|
|
|
|
// Same basic logic as above, but the result is negative.
|
|
if (MaxLHS.isNegative()) {
|
|
if (MinLHS.ugt(-MinAbsRHS))
|
|
return *this;
|
|
|
|
APInt Lower = APIntOps::umax(MinLHS, -MaxAbsRHS + 1);
|
|
return ConstantRange(std::move(Lower), APInt(getBitWidth(), 1));
|
|
}
|
|
|
|
// LHS range crosses zero.
|
|
APInt Lower = APIntOps::umax(MinLHS, -MaxAbsRHS + 1);
|
|
APInt Upper = APIntOps::umin(MaxLHS, MaxAbsRHS - 1) + 1;
|
|
return ConstantRange(std::move(Lower), std::move(Upper));
|
|
}
|
|
|
|
ConstantRange ConstantRange::binaryNot() const {
|
|
return ConstantRange(APInt::getAllOnesValue(getBitWidth())).sub(*this);
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::binaryAnd(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
|
|
// Use APInt's implementation of AND for single element ranges.
|
|
if (isSingleElement() && Other.isSingleElement())
|
|
return {*getSingleElement() & *Other.getSingleElement()};
|
|
|
|
// TODO: replace this with something less conservative
|
|
|
|
APInt umin = APIntOps::umin(Other.getUnsignedMax(), getUnsignedMax());
|
|
return getNonEmpty(APInt::getNullValue(getBitWidth()), std::move(umin) + 1);
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::binaryOr(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
|
|
// Use APInt's implementation of OR for single element ranges.
|
|
if (isSingleElement() && Other.isSingleElement())
|
|
return {*getSingleElement() | *Other.getSingleElement()};
|
|
|
|
// TODO: replace this with something less conservative
|
|
|
|
APInt umax = APIntOps::umax(getUnsignedMin(), Other.getUnsignedMin());
|
|
return getNonEmpty(std::move(umax), APInt::getNullValue(getBitWidth()));
|
|
}
|
|
|
|
ConstantRange ConstantRange::binaryXor(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
|
|
// Use APInt's implementation of XOR for single element ranges.
|
|
if (isSingleElement() && Other.isSingleElement())
|
|
return {*getSingleElement() ^ *Other.getSingleElement()};
|
|
|
|
// Special-case binary complement, since we can give a precise answer.
|
|
if (Other.isSingleElement() && Other.getSingleElement()->isAllOnesValue())
|
|
return binaryNot();
|
|
if (isSingleElement() && getSingleElement()->isAllOnesValue())
|
|
return Other.binaryNot();
|
|
|
|
// TODO: replace this with something less conservative
|
|
return getFull();
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::shl(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
|
|
APInt max = getUnsignedMax();
|
|
APInt Other_umax = Other.getUnsignedMax();
|
|
|
|
// If we are shifting by maximum amount of
|
|
// zero return return the original range.
|
|
if (Other_umax.isNullValue())
|
|
return *this;
|
|
// there's overflow!
|
|
if (Other_umax.ugt(max.countLeadingZeros()))
|
|
return getFull();
|
|
|
|
// FIXME: implement the other tricky cases
|
|
|
|
APInt min = getUnsignedMin();
|
|
min <<= Other.getUnsignedMin();
|
|
max <<= Other_umax;
|
|
|
|
return ConstantRange(std::move(min), std::move(max) + 1);
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::lshr(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
|
|
APInt max = getUnsignedMax().lshr(Other.getUnsignedMin()) + 1;
|
|
APInt min = getUnsignedMin().lshr(Other.getUnsignedMax());
|
|
return getNonEmpty(std::move(min), std::move(max));
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::ashr(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
|
|
// May straddle zero, so handle both positive and negative cases.
|
|
// 'PosMax' is the upper bound of the result of the ashr
|
|
// operation, when Upper of the LHS of ashr is a non-negative.
|
|
// number. Since ashr of a non-negative number will result in a
|
|
// smaller number, the Upper value of LHS is shifted right with
|
|
// the minimum value of 'Other' instead of the maximum value.
|
|
APInt PosMax = getSignedMax().ashr(Other.getUnsignedMin()) + 1;
|
|
|
|
// 'PosMin' is the lower bound of the result of the ashr
|
|
// operation, when Lower of the LHS is a non-negative number.
|
|
// Since ashr of a non-negative number will result in a smaller
|
|
// number, the Lower value of LHS is shifted right with the
|
|
// maximum value of 'Other'.
|
|
APInt PosMin = getSignedMin().ashr(Other.getUnsignedMax());
|
|
|
|
// 'NegMax' is the upper bound of the result of the ashr
|
|
// operation, when Upper of the LHS of ashr is a negative number.
|
|
// Since 'ashr' of a negative number will result in a bigger
|
|
// number, the Upper value of LHS is shifted right with the
|
|
// maximum value of 'Other'.
|
|
APInt NegMax = getSignedMax().ashr(Other.getUnsignedMax()) + 1;
|
|
|
|
// 'NegMin' is the lower bound of the result of the ashr
|
|
// operation, when Lower of the LHS of ashr is a negative number.
|
|
// Since 'ashr' of a negative number will result in a bigger
|
|
// number, the Lower value of LHS is shifted right with the
|
|
// minimum value of 'Other'.
|
|
APInt NegMin = getSignedMin().ashr(Other.getUnsignedMin());
|
|
|
|
APInt max, min;
|
|
if (getSignedMin().isNonNegative()) {
|
|
// Upper and Lower of LHS are non-negative.
|
|
min = PosMin;
|
|
max = PosMax;
|
|
} else if (getSignedMax().isNegative()) {
|
|
// Upper and Lower of LHS are negative.
|
|
min = NegMin;
|
|
max = NegMax;
|
|
} else {
|
|
// Upper is non-negative and Lower is negative.
|
|
min = NegMin;
|
|
max = PosMax;
|
|
}
|
|
return getNonEmpty(std::move(min), std::move(max));
|
|
}
|
|
|
|
ConstantRange ConstantRange::uadd_sat(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
|
|
APInt NewL = getUnsignedMin().uadd_sat(Other.getUnsignedMin());
|
|
APInt NewU = getUnsignedMax().uadd_sat(Other.getUnsignedMax()) + 1;
|
|
return getNonEmpty(std::move(NewL), std::move(NewU));
|
|
}
|
|
|
|
ConstantRange ConstantRange::sadd_sat(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
|
|
APInt NewL = getSignedMin().sadd_sat(Other.getSignedMin());
|
|
APInt NewU = getSignedMax().sadd_sat(Other.getSignedMax()) + 1;
|
|
return getNonEmpty(std::move(NewL), std::move(NewU));
|
|
}
|
|
|
|
ConstantRange ConstantRange::usub_sat(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
|
|
APInt NewL = getUnsignedMin().usub_sat(Other.getUnsignedMax());
|
|
APInt NewU = getUnsignedMax().usub_sat(Other.getUnsignedMin()) + 1;
|
|
return getNonEmpty(std::move(NewL), std::move(NewU));
|
|
}
|
|
|
|
ConstantRange ConstantRange::ssub_sat(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
|
|
APInt NewL = getSignedMin().ssub_sat(Other.getSignedMax());
|
|
APInt NewU = getSignedMax().ssub_sat(Other.getSignedMin()) + 1;
|
|
return getNonEmpty(std::move(NewL), std::move(NewU));
|
|
}
|
|
|
|
ConstantRange ConstantRange::umul_sat(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
|
|
APInt NewL = getUnsignedMin().umul_sat(Other.getUnsignedMin());
|
|
APInt NewU = getUnsignedMax().umul_sat(Other.getUnsignedMax()) + 1;
|
|
return getNonEmpty(std::move(NewL), std::move(NewU));
|
|
}
|
|
|
|
ConstantRange ConstantRange::smul_sat(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
|
|
// Because we could be dealing with negative numbers here, the lower bound is
|
|
// the smallest of the cartesian product of the lower and upper ranges;
|
|
// for example:
|
|
// [-1,4) * [-2,3) = min(-1*-2, -1*2, 3*-2, 3*2) = -6.
|
|
// Similarly for the upper bound, swapping min for max.
|
|
|
|
APInt this_min = getSignedMin().sext(getBitWidth() * 2);
|
|
APInt this_max = getSignedMax().sext(getBitWidth() * 2);
|
|
APInt Other_min = Other.getSignedMin().sext(getBitWidth() * 2);
|
|
APInt Other_max = Other.getSignedMax().sext(getBitWidth() * 2);
|
|
|
|
auto L = {this_min * Other_min, this_min * Other_max, this_max * Other_min,
|
|
this_max * Other_max};
|
|
auto Compare = [](const APInt &A, const APInt &B) { return A.slt(B); };
|
|
|
|
// Note that we wanted to perform signed saturating multiplication,
|
|
// so since we performed plain multiplication in twice the bitwidth,
|
|
// we need to perform signed saturating truncation.
|
|
return getNonEmpty(std::min(L, Compare).truncSSat(getBitWidth()),
|
|
std::max(L, Compare).truncSSat(getBitWidth()) + 1);
|
|
}
|
|
|
|
ConstantRange ConstantRange::ushl_sat(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
|
|
APInt NewL = getUnsignedMin().ushl_sat(Other.getUnsignedMin());
|
|
APInt NewU = getUnsignedMax().ushl_sat(Other.getUnsignedMax()) + 1;
|
|
return getNonEmpty(std::move(NewL), std::move(NewU));
|
|
}
|
|
|
|
ConstantRange ConstantRange::sshl_sat(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return getEmpty();
|
|
|
|
APInt Min = getSignedMin(), Max = getSignedMax();
|
|
APInt ShAmtMin = Other.getUnsignedMin(), ShAmtMax = Other.getUnsignedMax();
|
|
APInt NewL = Min.sshl_sat(Min.isNonNegative() ? ShAmtMin : ShAmtMax);
|
|
APInt NewU = Max.sshl_sat(Max.isNegative() ? ShAmtMin : ShAmtMax) + 1;
|
|
return getNonEmpty(std::move(NewL), std::move(NewU));
|
|
}
|
|
|
|
ConstantRange ConstantRange::inverse() const {
|
|
if (isFullSet())
|
|
return getEmpty();
|
|
if (isEmptySet())
|
|
return getFull();
|
|
return ConstantRange(Upper, Lower);
|
|
}
|
|
|
|
ConstantRange ConstantRange::abs(bool IntMinIsPoison) const {
|
|
if (isEmptySet())
|
|
return getEmpty();
|
|
|
|
if (isSignWrappedSet()) {
|
|
APInt Lo;
|
|
// Check whether the range crosses zero.
|
|
if (Upper.isStrictlyPositive() || !Lower.isStrictlyPositive())
|
|
Lo = APInt::getNullValue(getBitWidth());
|
|
else
|
|
Lo = APIntOps::umin(Lower, -Upper + 1);
|
|
|
|
// If SignedMin is not poison, then it is included in the result range.
|
|
if (IntMinIsPoison)
|
|
return ConstantRange(Lo, APInt::getSignedMinValue(getBitWidth()));
|
|
else
|
|
return ConstantRange(Lo, APInt::getSignedMinValue(getBitWidth()) + 1);
|
|
}
|
|
|
|
APInt SMin = getSignedMin(), SMax = getSignedMax();
|
|
|
|
// Skip SignedMin if it is poison.
|
|
if (IntMinIsPoison && SMin.isMinSignedValue()) {
|
|
// The range may become empty if it *only* contains SignedMin.
|
|
if (SMax.isMinSignedValue())
|
|
return getEmpty();
|
|
++SMin;
|
|
}
|
|
|
|
// All non-negative.
|
|
if (SMin.isNonNegative())
|
|
return *this;
|
|
|
|
// All negative.
|
|
if (SMax.isNegative())
|
|
return ConstantRange(-SMax, -SMin + 1);
|
|
|
|
// Range crosses zero.
|
|
return ConstantRange(APInt::getNullValue(getBitWidth()),
|
|
APIntOps::umax(-SMin, SMax) + 1);
|
|
}
|
|
|
|
ConstantRange::OverflowResult ConstantRange::unsignedAddMayOverflow(
|
|
const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return OverflowResult::MayOverflow;
|
|
|
|
APInt Min = getUnsignedMin(), Max = getUnsignedMax();
|
|
APInt OtherMin = Other.getUnsignedMin(), OtherMax = Other.getUnsignedMax();
|
|
|
|
// a u+ b overflows high iff a u> ~b.
|
|
if (Min.ugt(~OtherMin))
|
|
return OverflowResult::AlwaysOverflowsHigh;
|
|
if (Max.ugt(~OtherMax))
|
|
return OverflowResult::MayOverflow;
|
|
return OverflowResult::NeverOverflows;
|
|
}
|
|
|
|
ConstantRange::OverflowResult ConstantRange::signedAddMayOverflow(
|
|
const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return OverflowResult::MayOverflow;
|
|
|
|
APInt Min = getSignedMin(), Max = getSignedMax();
|
|
APInt OtherMin = Other.getSignedMin(), OtherMax = Other.getSignedMax();
|
|
|
|
APInt SignedMin = APInt::getSignedMinValue(getBitWidth());
|
|
APInt SignedMax = APInt::getSignedMaxValue(getBitWidth());
|
|
|
|
// a s+ b overflows high iff a s>=0 && b s>= 0 && a s> smax - b.
|
|
// a s+ b overflows low iff a s< 0 && b s< 0 && a s< smin - b.
|
|
if (Min.isNonNegative() && OtherMin.isNonNegative() &&
|
|
Min.sgt(SignedMax - OtherMin))
|
|
return OverflowResult::AlwaysOverflowsHigh;
|
|
if (Max.isNegative() && OtherMax.isNegative() &&
|
|
Max.slt(SignedMin - OtherMax))
|
|
return OverflowResult::AlwaysOverflowsLow;
|
|
|
|
if (Max.isNonNegative() && OtherMax.isNonNegative() &&
|
|
Max.sgt(SignedMax - OtherMax))
|
|
return OverflowResult::MayOverflow;
|
|
if (Min.isNegative() && OtherMin.isNegative() &&
|
|
Min.slt(SignedMin - OtherMin))
|
|
return OverflowResult::MayOverflow;
|
|
|
|
return OverflowResult::NeverOverflows;
|
|
}
|
|
|
|
ConstantRange::OverflowResult ConstantRange::unsignedSubMayOverflow(
|
|
const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return OverflowResult::MayOverflow;
|
|
|
|
APInt Min = getUnsignedMin(), Max = getUnsignedMax();
|
|
APInt OtherMin = Other.getUnsignedMin(), OtherMax = Other.getUnsignedMax();
|
|
|
|
// a u- b overflows low iff a u< b.
|
|
if (Max.ult(OtherMin))
|
|
return OverflowResult::AlwaysOverflowsLow;
|
|
if (Min.ult(OtherMax))
|
|
return OverflowResult::MayOverflow;
|
|
return OverflowResult::NeverOverflows;
|
|
}
|
|
|
|
ConstantRange::OverflowResult ConstantRange::signedSubMayOverflow(
|
|
const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return OverflowResult::MayOverflow;
|
|
|
|
APInt Min = getSignedMin(), Max = getSignedMax();
|
|
APInt OtherMin = Other.getSignedMin(), OtherMax = Other.getSignedMax();
|
|
|
|
APInt SignedMin = APInt::getSignedMinValue(getBitWidth());
|
|
APInt SignedMax = APInt::getSignedMaxValue(getBitWidth());
|
|
|
|
// a s- b overflows high iff a s>=0 && b s< 0 && a s> smax + b.
|
|
// a s- b overflows low iff a s< 0 && b s>= 0 && a s< smin + b.
|
|
if (Min.isNonNegative() && OtherMax.isNegative() &&
|
|
Min.sgt(SignedMax + OtherMax))
|
|
return OverflowResult::AlwaysOverflowsHigh;
|
|
if (Max.isNegative() && OtherMin.isNonNegative() &&
|
|
Max.slt(SignedMin + OtherMin))
|
|
return OverflowResult::AlwaysOverflowsLow;
|
|
|
|
if (Max.isNonNegative() && OtherMin.isNegative() &&
|
|
Max.sgt(SignedMax + OtherMin))
|
|
return OverflowResult::MayOverflow;
|
|
if (Min.isNegative() && OtherMax.isNonNegative() &&
|
|
Min.slt(SignedMin + OtherMax))
|
|
return OverflowResult::MayOverflow;
|
|
|
|
return OverflowResult::NeverOverflows;
|
|
}
|
|
|
|
ConstantRange::OverflowResult ConstantRange::unsignedMulMayOverflow(
|
|
const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return OverflowResult::MayOverflow;
|
|
|
|
APInt Min = getUnsignedMin(), Max = getUnsignedMax();
|
|
APInt OtherMin = Other.getUnsignedMin(), OtherMax = Other.getUnsignedMax();
|
|
bool Overflow;
|
|
|
|
(void) Min.umul_ov(OtherMin, Overflow);
|
|
if (Overflow)
|
|
return OverflowResult::AlwaysOverflowsHigh;
|
|
|
|
(void) Max.umul_ov(OtherMax, Overflow);
|
|
if (Overflow)
|
|
return OverflowResult::MayOverflow;
|
|
|
|
return OverflowResult::NeverOverflows;
|
|
}
|
|
|
|
void ConstantRange::print(raw_ostream &OS) const {
|
|
if (isFullSet())
|
|
OS << "full-set";
|
|
else if (isEmptySet())
|
|
OS << "empty-set";
|
|
else
|
|
OS << "[" << Lower << "," << Upper << ")";
|
|
}
|
|
|
|
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
|
|
LLVM_DUMP_METHOD void ConstantRange::dump() const {
|
|
print(dbgs());
|
|
}
|
|
#endif
|
|
|
|
ConstantRange llvm::getConstantRangeFromMetadata(const MDNode &Ranges) {
|
|
const unsigned NumRanges = Ranges.getNumOperands() / 2;
|
|
assert(NumRanges >= 1 && "Must have at least one range!");
|
|
assert(Ranges.getNumOperands() % 2 == 0 && "Must be a sequence of pairs");
|
|
|
|
auto *FirstLow = mdconst::extract<ConstantInt>(Ranges.getOperand(0));
|
|
auto *FirstHigh = mdconst::extract<ConstantInt>(Ranges.getOperand(1));
|
|
|
|
ConstantRange CR(FirstLow->getValue(), FirstHigh->getValue());
|
|
|
|
for (unsigned i = 1; i < NumRanges; ++i) {
|
|
auto *Low = mdconst::extract<ConstantInt>(Ranges.getOperand(2 * i + 0));
|
|
auto *High = mdconst::extract<ConstantInt>(Ranges.getOperand(2 * i + 1));
|
|
|
|
// Note: unionWith will potentially create a range that contains values not
|
|
// contained in any of the original N ranges.
|
|
CR = CR.unionWith(ConstantRange(Low->getValue(), High->getValue()));
|
|
}
|
|
|
|
return CR;
|
|
}
|