// intersect1Wrapped - This helper function is used to intersect two ranges when
// it is known that LHS is wrapped and RHS isn't.
//
ConstantRange
ConstantRange::intersect1Wrapped(const ConstantRange &LHS,
const ConstantRange &RHS) {
assert(LHS.isWrappedSet() && !RHS.isWrappedSet());
// Check to see if we overlap on the Left side of RHS...
//
if (RHS.Lower.ult(LHS.Upper)) {
// We do overlap on the left side of RHS, see if we overlap on the right of
// RHS...
if (RHS.Upper.ugt(LHS.Lower)) {
// Ok, the result overlaps on both the left and right sides. See if the
// resultant interval will be smaller if we wrap or not...
//
if (LHS.getSetSize().ult(RHS.getSetSize()))
return LHS;
else
return RHS;
} else {
// No overlap on the right, just on the left.
return ConstantRange(RHS.Lower, LHS.Upper);
}
} else {
// We don't overlap on the left side of RHS, see if we overlap on the right
// of RHS...
if (RHS.Upper.ugt(LHS.Lower)) {
// Simple overlap...
return ConstantRange(LHS.Lower, RHS.Upper);
} else {
// No overlap...
return ConstantRange(LHS.getBitWidth(), false);
}
}
}
/// intersectWith - Return the range that results from the intersection of this
/// range with another range.
///
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;
}
/// contains - Return true if the argument is a subset of this range.
/// Two equal sets contain each other. The empty set contained by all other
/// sets.
///
bool ConstantRange::contains(const ConstantRange &Other) const {
if (isFullSet() || Other.isEmptySet()) return true;
if (isEmptySet() || Other.isFullSet()) 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());
}
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.getUpper().isNonNegative() || UR.getUpper().isMinSignedValue()))
return UR;
// Now the signed range. Because we could be dealing with negative numbers
// here, the lower bound is the smallest of the cartesian product of the
// lower and upper ranges; for example:
// [-1,4) * [-2,3) = min(-1*-2, -1*2, 3*-2, 3*2) = -6.
// Similarly for the upper bound, swapping min for max.
this_min = getSignedMin().sext(getBitWidth() * 2);
this_max = getSignedMax().sext(getBitWidth() * 2);
Other_min = Other.getSignedMin().sext(getBitWidth() * 2);
Other_max = Other.getSignedMax().sext(getBitWidth() * 2);
auto L = {this_min * Other_min, this_min * Other_max,
this_max * Other_min, this_max * Other_max};
auto Compare = [](const APInt &A, const APInt &B) { return A.slt(B); };
ConstantRange Result_sext(std::min(L, Compare), std::max(L, Compare) + 1);
ConstantRange SR = Result_sext.truncate(getBitWidth());
return UR.isSizeStrictlySmallerThan(SR) ? UR : SR;
}
MyConstantRange binaryAnd(const ConstantRange &Other) const {
if (isEmptySet() || Other.isEmptySet())
return MyConstantRange(getBitWidth(), /*isFullSet=*/false);
if (!isWrappedSet() && !Other.isWrappedSet() && !isFullSet() && !Other.isFullSet()) {
unsigned width1 = ((getUpper() - 1) ^ getLower()).logBase2() + 1;
unsigned width2 = ((Other.getUpper() - 1) ^ Other.getLower()).logBase2() + 1;
APInt res1 = getLower().lshr(width1) << width1;
APInt res2 = Other.getLower().lshr(width2) << width2;
APInt res_high1 = getLower();
APInt res_high2 = Other.getLower();
res_high1.setLowBits(width1);
res_high2.setLowBits(width2);
if ((res1 & res2).isNullValue() && (res_high1 & res_high2).isAllOnesValue()) {
return MyConstantRange(getBitWidth(), /*isFullSet=*/true);
}
return MyConstantRange(res1 & res2, (res_high1 & res_high2) + 1);
}
APInt umin = APIntOps::umin(Other.getUnsignedMax(), getUnsignedMax());
if (umin.isAllOnesValue())
return MyConstantRange(getBitWidth(), /*isFullSet=*/true);
return MyConstantRange(APInt::getNullValue(getBitWidth()), std::move(umin) + 1);
}
/// unionWith - Return the range that results from the union of this range with
/// another range. The resultant range is guaranteed to include the elements of
/// both sets, but may contain more. For example, [3, 9) union [12,15) is
/// [3, 15), which includes 9, 10, and 11, which were not included in either
/// set before.
///
ConstantRange ConstantRange::unionWith(const ConstantRange &CR) const {
assert(getBitWidth() == CR.getBitWidth() &&
"ConstantRange types don't agree!");
if ( isFullSet() || CR.isEmptySet()) return *this;
if (CR.isFullSet() || isEmptySet()) return CR;
if (!isWrappedSet() && CR.isWrappedSet()) return CR.unionWith(*this);
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);
return ConstantRange(CR.Lower, Upper);
}
APInt L = Lower, U = Upper;
if (CR.Lower.ult(L))
L = CR.Lower;
if ((CR.Upper - 1).ugt(U - 1))
U = CR.Upper;
if (L == 0 && U == 0)
return ConstantRange(getBitWidth());
return ConstantRange(L, U);
}
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;
// ------U L----- : this
// L---------U : CR
if (CR.Lower.ule(Upper) && Lower.ule(CR.Upper))
return ConstantRange(getBitWidth());
// ----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))
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);
}
/// intersectWith - 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.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 cases.
if ( isEmptySet() || CR.isFullSet()) return *this;
if (CR.isEmptySet() || isFullSet()) return CR;
if (!isWrappedSet() && CR.isWrappedSet())
return CR.intersectWith(*this);
if (!isWrappedSet() && !CR.isWrappedSet()) {
if (Lower.ult(CR.Lower)) {
if (Upper.ule(CR.Lower))
return ConstantRange(getBitWidth(), false);
if (Upper.ult(CR.Upper))
return ConstantRange(CR.Lower, Upper);
return CR;
}
if (Upper.ult(CR.Upper))
return *this;
if (Lower.ult(CR.Upper))
return ConstantRange(Lower, CR.Upper);
return ConstantRange(getBitWidth(), false);
}
if (isWrappedSet() && !CR.isWrappedSet()) {
if (CR.Lower.ult(Upper)) {
if (CR.Upper.ult(Upper))
return CR;
if (CR.Upper.ule(Lower))
return ConstantRange(CR.Lower, Upper);
if (getSetSize().ult(CR.getSetSize()))
return *this;
return CR;
}
if (CR.Lower.ult(Lower)) {
if (CR.Upper.ule(Lower))
return ConstantRange(getBitWidth(), false);
return ConstantRange(Lower, CR.Upper);
}
return CR;
}
if (CR.Upper.ult(Upper)) {
if (CR.Lower.ult(Upper)) {
if (getSetSize().ult(CR.getSetSize()))
return *this;
return CR;
}
if (CR.Lower.ult(Lower))
return ConstantRange(Lower, CR.Upper);
return CR;
}
if (CR.Upper.ule(Lower)) {
if (CR.Lower.ult(Lower))
return *this;
return ConstantRange(CR.Lower, Upper);
}
if (getSetSize().ult(CR.getSetSize()))
return *this;
return CR;
}
/// unionWith - Return the range that results from the union of this range with
/// another range. The resultant range is guaranteed to include the elements of
/// both sets, but may contain more. For example, [3, 9) union [12,15) is
/// [3, 15), which includes 9, 10, and 11, which were not included in either
/// set before.
///
ConstantRange ConstantRange::unionWith(const ConstantRange &CR) const {
assert(getBitWidth() == CR.getBitWidth() &&
"ConstantRange types don't agree!");
if ( isFullSet() || CR.isEmptySet()) return *this;
if (CR.isFullSet() || isEmptySet()) return CR;
if (!isWrappedSet() && CR.isWrappedSet()) return CR.unionWith(*this);
APInt L = Lower, U = Upper;
if (!isWrappedSet() && !CR.isWrappedSet()) {
if (CR.Lower.ult(L))
L = CR.Lower;
if (CR.Upper.ugt(U))
U = CR.Upper;
}
if (isWrappedSet() && !CR.isWrappedSet()) {
if ((CR.Lower.ult(Upper) && CR.Upper.ult(Upper)) ||
(CR.Lower.ugt(Lower) && CR.Upper.ugt(Lower))) {
return *this;
}
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)) {
APInt d1 = CR.Lower - Upper, d2 = Lower - CR.Upper;
if (d1.ult(d2)) {
U = CR.Lower + 1;
} else {
L = CR.Upper - 1;
}
}
if (Upper.ult(CR.Lower) && Lower.ult(CR.Upper)) {
APInt d1 = CR.Lower - Upper, d2 = Lower - CR.Lower;
if (d1.ult(d2)) {
U = CR.Lower + 1;
} else {
L = CR.Lower;
}
}
}
if (isWrappedSet() && CR.isWrappedSet()) {
if (Lower.ult(CR.Upper) || CR.Lower.ult(Upper))
return ConstantRange(getBitWidth());
if (CR.Upper.ugt(U)) {
U = CR.Upper;
}
if (CR.Lower.ult(L)) {
L = CR.Lower;
}
if (L == U) return ConstantRange(getBitWidth());
}
return ConstantRange(L, U);
}
