735 lines
24 KiB
C++
735 lines
24 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/InstrTypes.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::makeICmpRegion(unsigned 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: llvm_unreachable("Invalid ICmp predicate to makeICmpRegion()");
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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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/// 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
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// <d1> <d2>
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if (Upper.ule(CR.Lower) && CR.Upper.ule(Lower)) {
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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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// ----U L----- : this
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// L----U : CR
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if (Upper.ult(CR.Lower) && Lower.ult(CR.Upper))
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return ConstantRange(CR.Lower, Upper);
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// ------U L---- : this
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// L-----U : CR
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assert(CR.Lower.ult(Upper) && CR.Upper.ult(Lower) &&
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"ConstantRange::unionWith missed a case with one range wrapped");
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return ConstantRange(Lower, CR.Upper);
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}
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// ------U L---- and ------U L---- : this
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// -U L----------- and ------------U L : 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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APInt L = Lower, U = Upper;
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if (CR.Upper.ugt(U))
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U = CR.Upper;
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if (CR.Lower.ult(L))
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L = CR.Lower;
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return ConstantRange(L, U);
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}
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/// zeroExtend - Return a new range in the specified integer type, which must
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/// be strictly larger than the current type. The returned range will
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/// correspond to the possible range of values as if the source range had been
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/// zero extended.
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ConstantRange ConstantRange::zeroExtend(uint32_t DstTySize) const {
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if (isEmptySet()) return ConstantRange(DstTySize, /*isFullSet=*/false);
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unsigned SrcTySize = getBitWidth();
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assert(SrcTySize < DstTySize && "Not a value extension");
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if (isFullSet() || isWrappedSet()) {
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// Change into [0, 1 << src bit width)
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APInt LowerExt(DstTySize, 0);
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if (!Upper) // special case: [X, 0) -- not really wrapping around
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LowerExt = Lower.zext(DstTySize);
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return ConstantRange(LowerExt, APInt::getOneBitSet(DstTySize, SrcTySize));
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}
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return ConstantRange(Lower.zext(DstTySize), Upper.zext(DstTySize));
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}
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/// signExtend - Return a new range in the specified integer type, which must
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/// be strictly larger than the current type. The returned range will
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/// correspond to the possible range of values as if the source range had been
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/// sign extended.
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ConstantRange ConstantRange::signExtend(uint32_t DstTySize) const {
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if (isEmptySet()) return ConstantRange(DstTySize, /*isFullSet=*/false);
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unsigned SrcTySize = getBitWidth();
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assert(SrcTySize < DstTySize && "Not a value extension");
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// special case: [X, INT_MIN) -- not really wrapping around
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if (Upper.isMinSignedValue())
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return ConstantRange(Lower.sext(DstTySize), Upper.zext(DstTySize));
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if (isFullSet() || isSignWrappedSet()) {
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return ConstantRange(APInt::getHighBitsSet(DstTySize,DstTySize-SrcTySize+1),
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APInt::getLowBitsSet(DstTySize, SrcTySize-1) + 1);
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}
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return ConstantRange(Lower.sext(DstTySize), Upper.sext(DstTySize));
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}
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/// truncate - Return a new range in the specified integer type, which must be
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/// strictly smaller than the current type. The returned range will
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/// correspond to the possible range of values as if the source range had been
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/// truncated to the specified type.
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ConstantRange ConstantRange::truncate(uint32_t DstTySize) const {
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assert(getBitWidth() > DstTySize && "Not a value truncation");
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if (isEmptySet())
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return ConstantRange(DstTySize, /*isFullSet=*/false);
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if (isFullSet())
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return ConstantRange(DstTySize, /*isFullSet=*/true);
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APInt MaxValue = APInt::getMaxValue(DstTySize).zext(getBitWidth());
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APInt MaxBitValue(getBitWidth(), 0);
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MaxBitValue.setBit(DstTySize);
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APInt LowerDiv(Lower), UpperDiv(Upper);
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ConstantRange Union(DstTySize, /*isFullSet=*/false);
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// Analyze wrapped sets in their two parts: [0, Upper) \/ [Lower, MaxValue]
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// We use the non-wrapped set code to analyze the [Lower, MaxValue) part, and
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// then we do the union with [MaxValue, Upper)
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if (isWrappedSet()) {
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// if Upper is greater than Max Value, it covers the whole truncated range.
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if (Upper.uge(MaxValue))
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return ConstantRange(DstTySize, /*isFullSet=*/true);
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Union = ConstantRange(APInt::getMaxValue(DstTySize),Upper.trunc(DstTySize));
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UpperDiv = APInt::getMaxValue(getBitWidth());
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// Union covers the MaxValue case, so return if the remaining range is just
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// MaxValue.
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if (LowerDiv == UpperDiv)
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return Union;
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}
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// Chop off the most significant bits that are past the destination bitwidth.
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if (LowerDiv.uge(MaxValue)) {
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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);
|
|
|
|
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);
|
|
return Result_zext.truncate(getBitWidth());
|
|
}
|
|
|
|
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::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...
|
|
///
|
|
void ConstantRange::dump() const {
|
|
print(dbgs());
|
|
}
|