diff options
Diffstat (limited to 'lib/Support/ConstantRange.cpp')
-rw-r--r-- | lib/Support/ConstantRange.cpp | 330 |
1 files changed, 229 insertions, 101 deletions
diff --git a/lib/Support/ConstantRange.cpp b/lib/Support/ConstantRange.cpp index cb8c4b0..423e90d 100644 --- a/lib/Support/ConstantRange.cpp +++ b/lib/Support/ConstantRange.cpp @@ -23,12 +23,12 @@ #include "llvm/Support/ConstantRange.h" #include "llvm/Support/raw_ostream.h" +#include "llvm/Instructions.h" using namespace llvm; /// Initialize a full (the default) or empty set for the specified type. /// -ConstantRange::ConstantRange(uint32_t BitWidth, bool Full) : - Lower(BitWidth, 0), Upper(BitWidth, 0) { +ConstantRange::ConstantRange(uint32_t BitWidth, bool Full) { if (Full) Lower = Upper = APInt::getMaxValue(BitWidth); else @@ -37,16 +37,63 @@ ConstantRange::ConstantRange(uint32_t BitWidth, bool Full) : /// Initialize a range to hold the single specified value. /// -ConstantRange::ConstantRange(const APInt & V) : Lower(V), Upper(V + 1) { } +ConstantRange::ConstantRange(const APInt & V) : Lower(V), Upper(V + 1) {} ConstantRange::ConstantRange(const APInt &L, const APInt &U) : Lower(L), Upper(U) { - assert(L.getBitWidth() == U.getBitWidth() && + assert(L.getBitWidth() == U.getBitWidth() && "ConstantRange with unequal bit widths"); assert((L != U || (L.isMaxValue() || L.isMinValue())) && "Lower == Upper, but they aren't min or max value!"); } +ConstantRange ConstantRange::makeICmpRegion(unsigned Pred, + const ConstantRange &CR) { + uint32_t W = CR.getBitWidth(); + switch (Pred) { + default: assert(!"Invalid ICmp predicate to makeICmpRegion()"); + case ICmpInst::ICMP_EQ: + return CR; + case ICmpInst::ICMP_NE: + if (CR.isSingleElement()) + return ConstantRange(CR.getUpper(), CR.getLower()); + return ConstantRange(W); + case ICmpInst::ICMP_ULT: + return ConstantRange(APInt::getMinValue(W), CR.getUnsignedMax()); + case ICmpInst::ICMP_SLT: + return ConstantRange(APInt::getSignedMinValue(W), CR.getSignedMax()); + case ICmpInst::ICMP_ULE: { + APInt UMax(CR.getUnsignedMax()); + if (UMax.isMaxValue()) + return ConstantRange(W); + return ConstantRange(APInt::getMinValue(W), UMax + 1); + } + case ICmpInst::ICMP_SLE: { + APInt SMax(CR.getSignedMax()); + if (SMax.isMaxSignedValue() || (SMax+1).isMaxSignedValue()) + return ConstantRange(W); + return ConstantRange(APInt::getSignedMinValue(W), SMax + 1); + } + case ICmpInst::ICMP_UGT: + return ConstantRange(CR.getUnsignedMin() + 1, APInt::getNullValue(W)); + case ICmpInst::ICMP_SGT: + return ConstantRange(CR.getSignedMin() + 1, + APInt::getSignedMinValue(W)); + case ICmpInst::ICMP_UGE: { + APInt UMin(CR.getUnsignedMin()); + if (UMin.isMinValue()) + return ConstantRange(W); + return ConstantRange(UMin, APInt::getNullValue(W)); + } + case ICmpInst::ICMP_SGE: { + APInt SMin(CR.getSignedMin()); + if (SMin.isMinSignedValue()) + return ConstantRange(W); + return ConstantRange(SMin, APInt::getSignedMinValue(W)); + } + } +} + /// isFullSet - Return true if this set contains all of the elements possible /// for this data-type bool ConstantRange::isFullSet() const { @@ -112,14 +159,10 @@ APInt ConstantRange::getSignedMax() const { else return SignedMax; } else { - if ((getUpper() - 1).slt(getLower())) { - if (getLower() != SignedMax) - return SignedMax; - else - return getUpper() - 1; - } else { + if (getLower().isNegative() == getUpper().isNegative()) + return SignedMax; + else return getUpper() - 1; - } } } @@ -157,6 +200,30 @@ bool ConstantRange::contains(const APInt &V) const { return Lower.ule(V) || V.ult(Upper); } +/// contains - Return true if the argument is a subset of this range. +/// Two equal set contain each other. The empty set is considered to be +/// contained by all other sets. +/// +bool ConstantRange::contains(const ConstantRange &Other) const { + if (isFullSet()) return true; + if (Other.isFullSet()) return false; + if (Other.isEmptySet()) return true; + if (isEmptySet()) return false; + + if (!isWrappedSet()) { + if (Other.isWrappedSet()) + return false; + + return Lower.ule(Other.getLower()) && Other.getUpper().ule(Upper); + } + + if (!Other.isWrappedSet()) + return Other.getUpper().ule(Upper) || + Lower.ule(Other.getLower()); + + return Other.getUpper().ule(Upper) && Lower.ule(Other.getLower()); +} + /// subtract - Subtract the specified constant from the endpoints of this /// constant range. ConstantRange ConstantRange::subtract(const APInt &Val) const { @@ -208,59 +275,20 @@ ConstantRange::intersect1Wrapped(const ConstantRange &LHS, } /// intersectWith - Return the range that results from the intersection of this -/// range with another range. -/// +/// range with another range. The resultant range is guaranteed to include all +/// elements contained in both input ranges, and to have the smallest possible +/// set size that does so. Because there may be two intersections with the +/// same set size, A.intersectWith(B) might not be equal to B.intersectWith(A). ConstantRange ConstantRange::intersectWith(const ConstantRange &CR) const { assert(getBitWidth() == CR.getBitWidth() && "ConstantRange types don't agree!"); - // Handle common special cases - if (isEmptySet() || CR.isFullSet()) - return *this; - if (isFullSet() || CR.isEmptySet()) - return CR; - - if (!isWrappedSet()) { - if (!CR.isWrappedSet()) { - using namespace APIntOps; - APInt L = umax(Lower, CR.Lower); - APInt U = umin(Upper, CR.Upper); - - if (L.ult(U)) // If range isn't empty... - return ConstantRange(L, U); - else - return ConstantRange(getBitWidth(), false);// Otherwise, empty set - } else - return intersect1Wrapped(CR, *this); - } else { // We know "this" is wrapped... - if (!CR.isWrappedSet()) - return intersect1Wrapped(*this, CR); - else { - // Both ranges are wrapped... - using namespace APIntOps; - APInt L = umax(Lower, CR.Lower); - APInt U = umin(Upper, CR.Upper); - return ConstantRange(L, U); - } - } - return *this; -} - -/// maximalIntersectWith - Return the range that results from the intersection -/// of this range with another range. The resultant range is guaranteed to -/// include all elements contained in both input ranges, and to have the -/// smallest possible set size that does so. Because there may be two -/// intersections with the same set size, A.maximalIntersectWith(B) might not -/// be equal to B.maximalIntersect(A). -ConstantRange ConstantRange::maximalIntersectWith(const ConstantRange &CR) const { - assert(getBitWidth() == CR.getBitWidth() && - "ConstantRange types don't agree!"); // Handle common cases. if ( isEmptySet() || CR.isFullSet()) return *this; if (CR.isEmptySet() || isFullSet()) return CR; if (!isWrappedSet() && CR.isWrappedSet()) - return CR.maximalIntersectWith(*this); + return CR.intersectWith(*this); if (!isWrappedSet() && !CR.isWrappedSet()) { if (Lower.ult(CR.Lower)) { @@ -343,69 +371,74 @@ ConstantRange ConstantRange::unionWith(const ConstantRange &CR) const { if (!isWrappedSet() && CR.isWrappedSet()) return CR.unionWith(*this); - APInt L = Lower, U = Upper; - if (!isWrappedSet() && !CR.isWrappedSet()) { + if (CR.Upper.ult(Lower) || Upper.ult(CR.Lower)) { + // If the two ranges are disjoint, find the smaller gap and bridge it. + APInt d1 = CR.Lower - Upper, d2 = Lower - CR.Upper; + if (d1.ult(d2)) + return ConstantRange(Lower, CR.Upper); + else + return ConstantRange(CR.Lower, Upper); + } + + APInt L = Lower, U = Upper; if (CR.Lower.ult(L)) L = CR.Lower; - - if (CR.Upper.ugt(U)) + if ((CR.Upper - 1).ugt(U - 1)) U = CR.Upper; + + if (L == 0 && U == 0) + return ConstantRange(getBitWidth()); + + return ConstantRange(L, U); } - if (isWrappedSet() && !CR.isWrappedSet()) { - if ((CR.Lower.ult(Upper) && CR.Upper.ult(Upper)) || - (CR.Lower.ugt(Lower) && CR.Upper.ugt(Lower))) { + if (!CR.isWrappedSet()) { + // ------U L----- and ------U L----- : this + // L--U L--U : CR + if (CR.Upper.ule(Upper) || CR.Lower.uge(Lower)) return *this; - } - if (CR.Lower.ule(Upper) && Lower.ule(CR.Upper)) { + // ------U L----- : this + // L---------U : CR + if (CR.Lower.ule(Upper) && Lower.ule(CR.Upper)) return ConstantRange(getBitWidth()); - } - - if (CR.Lower.ule(Upper) && CR.Upper.ule(Lower)) { - APInt d1 = CR.Upper - Upper, d2 = Lower - CR.Upper; - if (d1.ult(d2)) { - U = CR.Upper; - } else { - L = CR.Upper; - } - } - if (Upper.ult(CR.Lower) && CR.Upper.ult(Lower)) { + // ----U L---- : this + // 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)) { - U = CR.Lower + 1; - } else { - L = CR.Upper - 1; - } + if (d1.ult(d2)) + return ConstantRange(Lower, CR.Upper); + else + return ConstantRange(CR.Lower, Upper); } - if (Upper.ult(CR.Lower) && Lower.ult(CR.Upper)) { - APInt d1 = CR.Lower - Upper, d2 = Lower - CR.Lower; + // ----U L----- : this + // L----U : CR + if (Upper.ult(CR.Lower) && Lower.ult(CR.Upper)) + return ConstantRange(CR.Lower, Upper); - if (d1.ult(d2)) { - U = CR.Lower + 1; - } else { - L = CR.Lower; - } - } + // ------U L---- : this + // L-----U : CR + if (CR.Lower.ult(Upper) && CR.Upper.ult(Lower)) + return ConstantRange(Lower, CR.Upper); } - if (isWrappedSet() && CR.isWrappedSet()) { - if (Lower.ult(CR.Upper) || CR.Lower.ult(Upper)) - return ConstantRange(getBitWidth()); + assert(isWrappedSet() && CR.isWrappedSet() && + "ConstantRange::unionWith missed wrapped union unwrapped case"); - if (CR.Upper.ugt(U)) { - U = CR.Upper; - } - - if (CR.Lower.ult(L)) { - L = CR.Lower; - } + // ------U L---- and ------U L---- : this + // -U L----------- and ------------U L : CR + if (CR.Lower.ule(Upper) || Lower.ule(CR.Upper)) + return ConstantRange(getBitWidth()); - if (L == U) 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); } @@ -435,7 +468,7 @@ ConstantRange ConstantRange::signExtend(uint32_t DstTySize) const { assert(SrcTySize < DstTySize && "Not a value extension"); if (isFullSet()) { return ConstantRange(APInt::getHighBitsSet(DstTySize,DstTySize-SrcTySize+1), - APInt::getLowBitsSet(DstTySize, SrcTySize-1)); + APInt::getLowBitsSet(DstTySize, SrcTySize-1) + 1); } APInt L = Lower; L.sext(DstTySize); @@ -459,6 +492,99 @@ ConstantRange ConstantRange::truncate(uint32_t DstTySize) const { return ConstantRange(L, U); } +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::multiply(const ConstantRange &Other) const { + if (isEmptySet() || Other.isEmptySet()) + return ConstantRange(getBitWidth(), /*isFullSet=*/false); + if (isFullSet() || Other.isFullSet()) + return ConstantRange(getBitWidth(), /*isFullSet=*/true); + + 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); +} + /// print - Print out the bounds to a stream... /// void ConstantRange::print(raw_ostream &OS) const { @@ -470,3 +596,5 @@ void ConstantRange::print(raw_ostream &OS) const { void ConstantRange::dump() const { print(errs()); } + + |