//
//===----------------------------------------------------------------------===//
+#include "llvm/Constants.h"
#include "llvm/Support/ConstantRange.h"
+#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Instructions.h"
using namespace llvm;
/// 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) {
return Lower.ugt(Upper);
}
+/// isSignWrappedSet - Return true if this set wraps around the INT_MIN of
+/// its bitwidth, for example: i8 [120, 140).
+///
+bool ConstantRange::isSignWrappedSet() const {
+ return contains(APInt::getSignedMaxValue(getBitWidth())) &&
+ contains(APInt::getSignedMinValue(getBitWidth()));
+}
+
/// getSetSize - Return the number of elements in this set.
///
APInt ConstantRange::getSetSize() 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;
- }
}
}
}
/// 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.
+/// Two equal sets contain each other. The empty set 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 (isFullSet() || Other.isEmptySet()) return true;
+ if (isEmptySet() || Other.isFullSet()) return false;
if (!isWrappedSet()) {
if (Other.isWrappedSet())
return ConstantRange(Lower - Val, Upper - Val);
}
-
-// 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.
-///
+/// 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()) {
- APInt L = APIntOps::umax(Lower, CR.Lower);
- APInt U = APIntOps::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...
- APInt L = APIntOps::umax(Lower, CR.Lower);
- APInt U = APIntOps::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!");
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)) {
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;
- }
+ // ------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 (CR.Lower.ult(L)) {
- L = CR.Lower;
- }
-
- 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);
}
/// 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())
- // Change a source full set into [0, 1 << 8*numbytes)
+ if (isFullSet() || isWrappedSet())
+ // Change into [0, 1 << src bit width)
return ConstantRange(APInt(DstTySize,0), APInt(DstTySize,1).shl(SrcTySize));
APInt L = Lower; L.zext(DstTySize);
/// 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");
- if (isFullSet()) {
+ if (isFullSet() || isSignWrappedSet()) {
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);
assert(SrcTySize > DstTySize && "Not a value truncation");
APInt Size(APInt::getLowBitsSet(SrcTySize, DstTySize));
if (isFullSet() || getSetSize().ugt(Size))
- return ConstantRange(DstTySize);
+ return ConstantRange(DstTySize, /*isFullSet=*/true);
APInt L = Lower; L.trunc(DstTySize);
APInt U = Upper; U.trunc(DstTySize);
return ConstantRange(L, U);
}
+/// 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);
+ else if (SrcTySize < DstTySize)
+ return zeroExtend(DstTySize);
+ else
+ 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);
+ else if (SrcTySize < DstTySize)
+ return signExtend(DstTySize);
+ else
+ return *this;
+}
+
ConstantRange
ConstantRange::add(const ConstantRange &Other) const {
if (isEmptySet() || Other.isEmptySet())
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.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 {
+ // 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);
if (isFullSet() || Other.isFullSet())
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);
+ } else 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 {
- OS << "[" << Lower << "," << Upper << ")";
+ 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(errs());
-}
-
-std::ostream &llvm::operator<<(std::ostream &o,
- const ConstantRange &CR) {
- raw_os_ostream OS(o);
- OS << CR;
- return o;
+ print(dbgs());
}