34a7a945b0
r231483 taught ConstantRange::multiply to be clever about signed vs unsigned ranges. For example, an unsigned range could be full-set while the signed range is more specific than that. In looking at the allocations trace for LTO'ing verify-uselistorder (see r236629 for details), millions of allocations are from APInt, many of which come from ConstantRange's. This change tries to avoid some (3.2 million) allocations by returning the unsigned range if its suitable. The checks here are that it should not be a wrapping range, and should be positive. That should be enough to check for ranges such as [1, 10) which the signed range will be equal to, if we were to calculate it. Differential Revision: http://reviews.llvm.org/D20723 Reviewed by James Molloy llvm-svn: 271020
904 lines
31 KiB
C++
904 lines
31 KiB
C++
//===-- ConstantRange.cpp - ConstantRange implementation ------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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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/IR/Instruction.h"
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#include "llvm/IR/InstrTypes.h"
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#include "llvm/IR/Operator.h"
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#include "llvm/IR/ConstantRange.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/raw_ostream.h"
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using namespace llvm;
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/// Initialize a full (the default) or empty set for the specified type.
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///
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ConstantRange::ConstantRange(uint32_t BitWidth, bool Full) {
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if (Full)
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Lower = Upper = APInt::getMaxValue(BitWidth);
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else
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Lower = Upper = APInt::getMinValue(BitWidth);
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}
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/// Initialize a range to hold the single specified value.
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///
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ConstantRange::ConstantRange(APIntMoveTy V)
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: Lower(std::move(V)), Upper(Lower + 1) {}
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ConstantRange::ConstantRange(APIntMoveTy L, APIntMoveTy 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::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 ConstantRange(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 ConstantRange(W, /* empty */ false);
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return ConstantRange(APInt::getMinValue(W), 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 ConstantRange(W, /* empty */ false);
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return ConstantRange(APInt::getSignedMinValue(W), SMax);
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}
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case CmpInst::ICMP_ULE: {
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APInt UMax(CR.getUnsignedMax());
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if (UMax.isMaxValue())
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return ConstantRange(W);
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return ConstantRange(APInt::getMinValue(W), UMax + 1);
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}
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case CmpInst::ICMP_SLE: {
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APInt SMax(CR.getSignedMax());
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if (SMax.isMaxSignedValue())
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return ConstantRange(W);
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return ConstantRange(APInt::getSignedMinValue(W), SMax + 1);
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}
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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 ConstantRange(W, /* empty */ false);
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return ConstantRange(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 ConstantRange(W, /* empty */ false);
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return ConstantRange(SMin + 1, APInt::getSignedMinValue(W));
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}
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case CmpInst::ICMP_UGE: {
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APInt UMin(CR.getUnsignedMin());
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if (UMin.isMinValue())
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return ConstantRange(W);
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return ConstantRange(UMin, APInt::getNullValue(W));
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}
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case CmpInst::ICMP_SGE: {
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APInt SMin(CR.getSignedMin());
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if (SMin.isMinSignedValue())
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return ConstantRange(W);
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return ConstantRange(SMin, APInt::getSignedMinValue(W));
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}
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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 (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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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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typedef OverflowingBinaryOperator OBO;
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// Computes the intersection of CR0 and CR1. It is different from
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// intersectWith in that the ConstantRange returned will only contain elements
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// in both CR0 and CR1 (i.e. SubsetIntersect(X, Y) is a *subset*, proper or
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// not, of both X and Y).
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auto SubsetIntersect =
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[](const ConstantRange &CR0, const ConstantRange &CR1) {
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return CR0.inverse().unionWith(CR1.inverse()).inverse();
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};
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assert(BinOp >= Instruction::BinaryOpsBegin &&
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BinOp < Instruction::BinaryOpsEnd && "Binary operators only!");
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assert((NoWrapKind == OBO::NoSignedWrap ||
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NoWrapKind == OBO::NoUnsignedWrap ||
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NoWrapKind == (OBO::NoUnsignedWrap | OBO::NoSignedWrap)) &&
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"NoWrapKind invalid!");
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unsigned BitWidth = Other.getBitWidth();
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if (BinOp != Instruction::Add)
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// Conservative answer: empty set
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return ConstantRange(BitWidth, false);
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if (auto *C = Other.getSingleElement())
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if (C->isMinValue())
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// Full set: nothing signed / unsigned wraps when added to 0.
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return ConstantRange(BitWidth);
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ConstantRange Result(BitWidth);
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if (NoWrapKind & OBO::NoUnsignedWrap)
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Result =
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SubsetIntersect(Result, ConstantRange(APInt::getNullValue(BitWidth),
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-Other.getUnsignedMax()));
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if (NoWrapKind & OBO::NoSignedWrap) {
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APInt SignedMin = Other.getSignedMin();
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APInt SignedMax = Other.getSignedMax();
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if (SignedMax.isStrictlyPositive())
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Result = SubsetIntersect(
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Result,
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ConstantRange(APInt::getSignedMinValue(BitWidth),
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APInt::getSignedMinValue(BitWidth) - SignedMax));
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if (SignedMin.isNegative())
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Result = SubsetIntersect(
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Result, ConstantRange(APInt::getSignedMinValue(BitWidth) - SignedMin,
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APInt::getSignedMinValue(BitWidth)));
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}
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return Result;
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}
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/// isFullSet - Return true if this set contains all of the elements possible
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/// for this data-type
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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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/// isEmptySet - Return true if this set contains no members.
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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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/// isWrappedSet - Return true if this set wraps around the top of the range,
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/// for example: [100, 8)
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///
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bool ConstantRange::isWrappedSet() const {
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return Lower.ugt(Upper);
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}
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/// isSignWrappedSet - Return true if this set wraps around the INT_MIN of
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/// its bitwidth, for example: i8 [120, 140).
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///
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bool ConstantRange::isSignWrappedSet() const {
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return contains(APInt::getSignedMaxValue(getBitWidth())) &&
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contains(APInt::getSignedMinValue(getBitWidth()));
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}
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/// getSetSize - Return the number of elements in this set.
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///
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APInt ConstantRange::getSetSize() const {
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if (isFullSet()) {
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APInt Size(getBitWidth()+1, 0);
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Size.setBit(getBitWidth());
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return Size;
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}
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// This is also correct for wrapped sets.
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return (Upper - Lower).zext(getBitWidth()+1);
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}
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/// getUnsignedMax - Return the largest unsigned value contained in the
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/// ConstantRange.
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///
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APInt ConstantRange::getUnsignedMax() const {
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if (isFullSet() || isWrappedSet())
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return APInt::getMaxValue(getBitWidth());
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return getUpper() - 1;
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}
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/// getUnsignedMin - Return the smallest unsigned value contained in the
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/// ConstantRange.
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///
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APInt ConstantRange::getUnsignedMin() const {
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if (isFullSet() || (isWrappedSet() && getUpper() != 0))
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return APInt::getMinValue(getBitWidth());
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return getLower();
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}
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/// getSignedMax - Return the largest signed value contained in the
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/// ConstantRange.
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///
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APInt ConstantRange::getSignedMax() const {
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APInt SignedMax(APInt::getSignedMaxValue(getBitWidth()));
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if (!isWrappedSet()) {
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if (getLower().sle(getUpper() - 1))
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return getUpper() - 1;
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return SignedMax;
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}
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if (getLower().isNegative() == getUpper().isNegative())
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return SignedMax;
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return getUpper() - 1;
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}
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/// getSignedMin - Return the smallest signed value contained in the
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/// ConstantRange.
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///
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APInt ConstantRange::getSignedMin() const {
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APInt SignedMin(APInt::getSignedMinValue(getBitWidth()));
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if (!isWrappedSet()) {
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if (getLower().sle(getUpper() - 1))
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return getLower();
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return SignedMin;
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}
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if ((getUpper() - 1).slt(getLower())) {
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if (getUpper() != SignedMin)
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return SignedMin;
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}
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return getLower();
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}
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/// contains - Return true if the specified value is in the set.
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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 (!isWrappedSet())
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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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/// contains - Return true if the argument is a subset of this range.
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/// Two equal sets contain each other. The empty set contained by all other
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/// sets.
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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 (!isWrappedSet()) {
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if (Other.isWrappedSet())
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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.isWrappedSet())
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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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/// subtract - Subtract the specified constant from the endpoints of this
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/// constant range.
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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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/// \brief Subtract the specified range from this range (aka relative complement
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/// of the sets).
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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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/// intersectWith - Return the range that results from the intersection of this
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/// range with another range. The resultant range is guaranteed to include all
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/// elements contained in both input ranges, and to have the smallest possible
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/// set size that does so. Because there may be two intersections with the
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/// same set size, A.intersectWith(B) might not be equal to B.intersectWith(A).
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ConstantRange ConstantRange::intersectWith(const ConstantRange &CR) 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;
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if (!isWrappedSet() && CR.isWrappedSet())
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return CR.intersectWith(*this);
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if (!isWrappedSet() && !CR.isWrappedSet()) {
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if (Lower.ult(CR.Lower)) {
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if (Upper.ule(CR.Lower))
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return ConstantRange(getBitWidth(), false);
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if (Upper.ult(CR.Upper))
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return ConstantRange(CR.Lower, Upper);
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return CR;
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}
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if (Upper.ult(CR.Upper))
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return *this;
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if (Lower.ult(CR.Upper))
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return ConstantRange(Lower, CR.Upper);
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return ConstantRange(getBitWidth(), false);
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}
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if (isWrappedSet() && !CR.isWrappedSet()) {
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if (CR.Lower.ult(Upper)) {
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if (CR.Upper.ult(Upper))
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return CR;
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if (CR.Upper.ule(Lower))
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return ConstantRange(CR.Lower, Upper);
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if (getSetSize().ult(CR.getSetSize()))
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return *this;
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return CR;
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}
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if (CR.Lower.ult(Lower)) {
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if (CR.Upper.ule(Lower))
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return ConstantRange(getBitWidth(), false);
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return ConstantRange(Lower, CR.Upper);
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}
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return CR;
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}
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if (CR.Upper.ult(Upper)) {
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if (CR.Lower.ult(Upper)) {
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if (getSetSize().ult(CR.getSetSize()))
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return *this;
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return CR;
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}
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if (CR.Lower.ult(Lower))
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return ConstantRange(Lower, CR.Upper);
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return CR;
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}
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if (CR.Upper.ule(Lower)) {
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if (CR.Lower.ult(Lower))
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return *this;
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return ConstantRange(CR.Lower, Upper);
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}
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if (getSetSize().ult(CR.getSetSize()))
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return *this;
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return CR;
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}
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/// unionWith - Return the range that results from the union of this range with
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/// another range. The resultant range is guaranteed to include the elements of
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/// both sets, but may contain more. For example, [3, 9) union [12,15) is
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/// [3, 15), which includes 9, 10, and 11, which were not included in either
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/// set before.
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///
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ConstantRange ConstantRange::unionWith(const ConstantRange &CR) const {
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assert(getBitWidth() == CR.getBitWidth() &&
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"ConstantRange types don't agree!");
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if ( isFullSet() || CR.isEmptySet()) return *this;
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if (CR.isFullSet() || isEmptySet()) return CR;
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if (!isWrappedSet() && CR.isWrappedSet()) return CR.unionWith(*this);
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if (!isWrappedSet() && !CR.isWrappedSet()) {
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if (CR.Upper.ult(Lower) || Upper.ult(CR.Lower)) {
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// If the two ranges are disjoint, find the smaller gap and bridge it.
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APInt d1 = CR.Lower - Upper, d2 = Lower - CR.Upper;
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if (d1.ult(d2))
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return ConstantRange(Lower, CR.Upper);
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return ConstantRange(CR.Lower, Upper);
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}
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APInt L = Lower, U = Upper;
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if (CR.Lower.ult(L))
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L = CR.Lower;
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if ((CR.Upper - 1).ugt(U - 1))
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U = CR.Upper;
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if (L == 0 && U == 0)
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return ConstantRange(getBitWidth());
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return ConstantRange(L, U);
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}
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if (!CR.isWrappedSet()) {
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// ------U L----- and ------U L----- : this
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// L--U L--U : CR
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if (CR.Upper.ule(Upper) || CR.Lower.uge(Lower))
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return *this;
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// ------U L----- : this
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// L---------U : CR
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if (CR.Lower.ule(Upper) && Lower.ule(CR.Upper))
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return ConstantRange(getBitWidth());
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// ----U L---- : this
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// L---U : CR
|
|
// <d1> <d2>
|
|
if (Upper.ule(CR.Lower) && CR.Upper.ule(Lower)) {
|
|
APInt d1 = CR.Lower - Upper, d2 = Lower - CR.Upper;
|
|
if (d1.ult(d2))
|
|
return ConstantRange(Lower, CR.Upper);
|
|
return ConstantRange(CR.Lower, Upper);
|
|
}
|
|
|
|
// ----U L----- : this
|
|
// L----U : CR
|
|
if (Upper.ult(CR.Lower) && Lower.ult(CR.Upper))
|
|
return ConstantRange(CR.Lower, Upper);
|
|
|
|
// ------U L---- : this
|
|
// L-----U : CR
|
|
assert(CR.Lower.ult(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 ConstantRange(getBitWidth());
|
|
|
|
APInt L = Lower, U = Upper;
|
|
if (CR.Upper.ugt(U))
|
|
U = CR.Upper;
|
|
if (CR.Lower.ult(L))
|
|
L = CR.Lower;
|
|
|
|
return ConstantRange(L, U);
|
|
}
|
|
|
|
/// zeroExtend - Return a new range in the specified integer type, which must
|
|
/// be strictly larger than the current type. The returned range will
|
|
/// correspond to the possible range of values as if the source range had been
|
|
/// zero extended.
|
|
ConstantRange ConstantRange::zeroExtend(uint32_t DstTySize) const {
|
|
if (isEmptySet()) return ConstantRange(DstTySize, /*isFullSet=*/false);
|
|
|
|
unsigned SrcTySize = getBitWidth();
|
|
assert(SrcTySize < DstTySize && "Not a value extension");
|
|
if (isFullSet() || isWrappedSet()) {
|
|
// 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(LowerExt, APInt::getOneBitSet(DstTySize, SrcTySize));
|
|
}
|
|
|
|
return ConstantRange(Lower.zext(DstTySize), Upper.zext(DstTySize));
|
|
}
|
|
|
|
/// signExtend - Return a new range in the specified integer type, which must
|
|
/// be strictly larger than the current type. The returned range will
|
|
/// correspond to the possible range of values as if the source range had been
|
|
/// sign extended.
|
|
ConstantRange ConstantRange::signExtend(uint32_t DstTySize) const {
|
|
if (isEmptySet()) return ConstantRange(DstTySize, /*isFullSet=*/false);
|
|
|
|
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));
|
|
}
|
|
|
|
/// truncate - Return a new range in the specified integer type, which must be
|
|
/// strictly smaller than the current type. The returned range will
|
|
/// correspond to the possible range of values as if the source range had been
|
|
/// truncated to the specified type.
|
|
ConstantRange ConstantRange::truncate(uint32_t DstTySize) const {
|
|
assert(getBitWidth() > DstTySize && "Not a value truncation");
|
|
if (isEmptySet())
|
|
return ConstantRange(DstTySize, /*isFullSet=*/false);
|
|
if (isFullSet())
|
|
return ConstantRange(DstTySize, /*isFullSet=*/true);
|
|
|
|
APInt MaxValue = APInt::getMaxValue(DstTySize).zext(getBitWidth());
|
|
APInt MaxBitValue(getBitWidth(), 0);
|
|
MaxBitValue.setBit(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 (isWrappedSet()) {
|
|
// if Upper is greater than Max Value, it covers the whole truncated range.
|
|
if (Upper.uge(MaxValue))
|
|
return ConstantRange(DstTySize, /*isFullSet=*/true);
|
|
|
|
Union = ConstantRange(APInt::getMaxValue(DstTySize),Upper.trunc(DstTySize));
|
|
UpperDiv = APInt::getMaxValue(getBitWidth());
|
|
|
|
// Union covers the MaxValue case, so return if the remaining range is just
|
|
// MaxValue.
|
|
if (LowerDiv == UpperDiv)
|
|
return Union;
|
|
}
|
|
|
|
// Chop off the most significant bits that are past the destination bitwidth.
|
|
if (LowerDiv.uge(MaxValue)) {
|
|
APInt Div(getBitWidth(), 0);
|
|
APInt::udivrem(LowerDiv, MaxBitValue, Div, LowerDiv);
|
|
UpperDiv = UpperDiv - MaxBitValue * Div;
|
|
}
|
|
|
|
if (UpperDiv.ule(MaxValue))
|
|
return ConstantRange(LowerDiv.trunc(DstTySize),
|
|
UpperDiv.trunc(DstTySize)).unionWith(Union);
|
|
|
|
// The truncated value wrapps around. Check if we can do better than fullset.
|
|
APInt UpperModulo = UpperDiv - MaxBitValue;
|
|
if (UpperModulo.ult(LowerDiv))
|
|
return ConstantRange(LowerDiv.trunc(DstTySize),
|
|
UpperModulo.trunc(DstTySize)).unionWith(Union);
|
|
|
|
return ConstantRange(DstTySize, /*isFullSet=*/true);
|
|
}
|
|
|
|
/// zextOrTrunc - make this range have the bit width given by \p DstTySize. The
|
|
/// value is zero extended, truncated, or left alone to make it that width.
|
|
ConstantRange ConstantRange::zextOrTrunc(uint32_t DstTySize) const {
|
|
unsigned SrcTySize = getBitWidth();
|
|
if (SrcTySize > DstTySize)
|
|
return truncate(DstTySize);
|
|
if (SrcTySize < DstTySize)
|
|
return zeroExtend(DstTySize);
|
|
return *this;
|
|
}
|
|
|
|
/// sextOrTrunc - make this range have the bit width given by \p DstTySize. The
|
|
/// value is sign extended, truncated, or left alone to make it that width.
|
|
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::add(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
|
|
if (isFullSet() || Other.isFullSet())
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
|
|
|
|
APInt Spread_X = getSetSize(), Spread_Y = Other.getSetSize();
|
|
APInt NewLower = getLower() + Other.getLower();
|
|
APInt NewUpper = getUpper() + Other.getUpper() - 1;
|
|
if (NewLower == NewUpper)
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
|
|
|
|
ConstantRange X = ConstantRange(NewLower, NewUpper);
|
|
if (X.getSetSize().ult(Spread_X) || X.getSetSize().ult(Spread_Y))
|
|
// We've wrapped, therefore, full set.
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
|
|
|
|
return X;
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::sub(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
|
|
if (isFullSet() || Other.isFullSet())
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
|
|
|
|
APInt Spread_X = getSetSize(), Spread_Y = Other.getSetSize();
|
|
APInt NewLower = getLower() - Other.getUpper() + 1;
|
|
APInt NewUpper = getUpper() - Other.getLower();
|
|
if (NewLower == NewUpper)
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
|
|
|
|
ConstantRange X = ConstantRange(NewLower, NewUpper);
|
|
if (X.getSetSize().ult(Spread_X) || X.getSetSize().ult(Spread_Y))
|
|
// We've wrapped, therefore, full set.
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
|
|
|
|
return X;
|
|
}
|
|
|
|
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 ConstantRange(getBitWidth(), /*isFullSet=*/false);
|
|
|
|
// 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.isWrappedSet() && UR.getLower().isNonNegative())
|
|
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.getSetSize().ult(SR.getSetSize()) ? 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 ConstantRange(getBitWidth(), /*isFullSet=*/false);
|
|
APInt NewL = APIntOps::smax(getSignedMin(), Other.getSignedMin());
|
|
APInt NewU = APIntOps::smax(getSignedMax(), Other.getSignedMax()) + 1;
|
|
if (NewU == NewL)
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
|
|
return ConstantRange(NewL, NewU);
|
|
}
|
|
|
|
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 ConstantRange(getBitWidth(), /*isFullSet=*/false);
|
|
APInt NewL = APIntOps::umax(getUnsignedMin(), Other.getUnsignedMin());
|
|
APInt NewU = APIntOps::umax(getUnsignedMax(), Other.getUnsignedMax()) + 1;
|
|
if (NewU == NewL)
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
|
|
return ConstantRange(NewL, NewU);
|
|
}
|
|
|
|
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 ConstantRange(getBitWidth(), /*isFullSet=*/false);
|
|
APInt NewL = APIntOps::smin(getSignedMin(), Other.getSignedMin());
|
|
APInt NewU = APIntOps::smin(getSignedMax(), Other.getSignedMax()) + 1;
|
|
if (NewU == NewL)
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
|
|
return ConstantRange(NewL, NewU);
|
|
}
|
|
|
|
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 ConstantRange(getBitWidth(), /*isFullSet=*/false);
|
|
APInt NewL = APIntOps::umin(getUnsignedMin(), Other.getUnsignedMin());
|
|
APInt NewU = APIntOps::umin(getUnsignedMax(), Other.getUnsignedMax()) + 1;
|
|
if (NewU == NewL)
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
|
|
return ConstantRange(NewL, NewU);
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::udiv(const ConstantRange &RHS) const {
|
|
if (isEmptySet() || RHS.isEmptySet() || RHS.getUnsignedMax() == 0)
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
|
|
if (RHS.isFullSet())
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
|
|
|
|
APInt Lower = getUnsignedMin().udiv(RHS.getUnsignedMax());
|
|
|
|
APInt RHS_umin = RHS.getUnsignedMin();
|
|
if (RHS_umin == 0) {
|
|
// 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 = APInt(getBitWidth(), 1);
|
|
}
|
|
|
|
APInt Upper = getUnsignedMax().udiv(RHS_umin) + 1;
|
|
|
|
// If the LHS is Full and the RHS is a wrapped interval containing 1 then
|
|
// this could occur.
|
|
if (Lower == Upper)
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
|
|
|
|
return ConstantRange(Lower, Upper);
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::binaryAnd(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
|
|
|
|
// TODO: replace this with something less conservative
|
|
|
|
APInt umin = APIntOps::umin(Other.getUnsignedMax(), getUnsignedMax());
|
|
if (umin.isAllOnesValue())
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
|
|
return ConstantRange(APInt::getNullValue(getBitWidth()), umin + 1);
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::binaryOr(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
|
|
|
|
// TODO: replace this with something less conservative
|
|
|
|
APInt umax = APIntOps::umax(getUnsignedMin(), Other.getUnsignedMin());
|
|
if (umax.isMinValue())
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
|
|
return ConstantRange(umax, APInt::getNullValue(getBitWidth()));
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::shl(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
|
|
|
|
APInt min = getUnsignedMin().shl(Other.getUnsignedMin());
|
|
APInt max = getUnsignedMax().shl(Other.getUnsignedMax());
|
|
|
|
// there's no overflow!
|
|
APInt Zeros(getBitWidth(), getUnsignedMax().countLeadingZeros());
|
|
if (Zeros.ugt(Other.getUnsignedMax()))
|
|
return ConstantRange(min, max + 1);
|
|
|
|
// FIXME: implement the other tricky cases
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
|
|
}
|
|
|
|
ConstantRange
|
|
ConstantRange::lshr(const ConstantRange &Other) const {
|
|
if (isEmptySet() || Other.isEmptySet())
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
|
|
|
|
APInt max = getUnsignedMax().lshr(Other.getUnsignedMin());
|
|
APInt min = getUnsignedMin().lshr(Other.getUnsignedMax());
|
|
if (min == max + 1)
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
|
|
|
|
return ConstantRange(min, max + 1);
|
|
}
|
|
|
|
ConstantRange ConstantRange::inverse() const {
|
|
if (isFullSet())
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
|
|
if (isEmptySet())
|
|
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
|
|
return ConstantRange(Upper, Lower);
|
|
}
|
|
|
|
/// print - Print out the bounds to a stream...
|
|
///
|
|
void ConstantRange::print(raw_ostream &OS) const {
|
|
if (isFullSet())
|
|
OS << "full-set";
|
|
else if (isEmptySet())
|
|
OS << "empty-set";
|
|
else
|
|
OS << "[" << Lower << "," << Upper << ")";
|
|
}
|
|
|
|
/// dump - Allow printing from a debugger easily...
|
|
///
|
|
LLVM_DUMP_METHOD void ConstantRange::dump() const {
|
|
print(dbgs());
|
|
}
|