It's not necessary to do rounding for alloca operations when the requested
alignment is equal to the stack alignment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40004 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/ConstantRange.cpp b/lib/Support/ConstantRange.cpp
new file mode 100644
index 0000000..fdfe28a
--- /dev/null
+++ b/lib/Support/ConstantRange.cpp
@@ -0,0 +1,474 @@
+//===-- ConstantRange.cpp - ConstantRange implementation ------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Represent a range of possible values that may occur when the program is run
+// for an integral value. This keeps track of a lower and upper bound for the
+// constant, which MAY wrap around the end of the numeric range. To do this, it
+// keeps track of a [lower, upper) bound, which specifies an interval just like
+// STL iterators. When used with boolean values, the following are important
+// ranges (other integral ranges use min/max values for special range values):
+//
+// [F, F) = {} = Empty set
+// [T, F) = {T}
+// [F, T) = {F}
+// [T, T) = {F, T} = Full set
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/ConstantRange.h"
+#include "llvm/Support/Streams.h"
+#include <ostream>
+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) {
+ if (Full)
+ Lower = Upper = APInt::getMaxValue(BitWidth);
+ else
+ Lower = Upper = APInt::getMinValue(BitWidth);
+}
+
+/// Initialize a range to hold the single specified value.
+///
+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() &&
+ "ConstantRange with unequal bit widths");
+ assert((L != U || (L.isMaxValue() || L.isMinValue())) &&
+ "Lower == Upper, but they aren't min or max value!");
+}
+
+/// isFullSet - Return true if this set contains all of the elements possible
+/// for this data-type
+bool ConstantRange::isFullSet() const {
+ return Lower == Upper && Lower.isMaxValue();
+}
+
+/// isEmptySet - Return true if this set contains no members.
+///
+bool ConstantRange::isEmptySet() const {
+ return Lower == Upper && Lower.isMinValue();
+}
+
+/// isWrappedSet - Return true if this set wraps around the top of the range,
+/// for example: [100, 8)
+///
+bool ConstantRange::isWrappedSet() const {
+ return Lower.ugt(Upper);
+}
+
+/// getSetSize - Return the number of elements in this set.
+///
+APInt ConstantRange::getSetSize() const {
+ if (isEmptySet())
+ return APInt(getBitWidth(), 0);
+ if (getBitWidth() == 1) {
+ if (Lower != Upper) // One of T or F in the set...
+ return APInt(2, 1);
+ return APInt(2, 2); // Must be full set...
+ }
+
+ // Simply subtract the bounds...
+ return Upper - Lower;
+}
+
+/// getUnsignedMax - Return the largest unsigned value contained in the
+/// ConstantRange.
+///
+APInt ConstantRange::getUnsignedMax() const {
+ if (isFullSet() || isWrappedSet())
+ return APInt::getMaxValue(getBitWidth());
+ else
+ return getUpper() - 1;
+}
+
+/// getUnsignedMin - Return the smallest unsigned value contained in the
+/// ConstantRange.
+///
+APInt ConstantRange::getUnsignedMin() const {
+ if (isFullSet() || (isWrappedSet() && getUpper() != 0))
+ return APInt::getMinValue(getBitWidth());
+ else
+ return getLower();
+}
+
+/// getSignedMax - Return the largest signed value contained in the
+/// ConstantRange.
+///
+APInt ConstantRange::getSignedMax() const {
+ APInt SignedMax(APInt::getSignedMaxValue(getBitWidth()));
+ if (!isWrappedSet()) {
+ if (getLower().sle(getUpper() - 1))
+ return getUpper() - 1;
+ else
+ return SignedMax;
+ } else {
+ if ((getUpper() - 1).slt(getLower())) {
+ if (getLower() != SignedMax)
+ return SignedMax;
+ else
+ return getUpper() - 1;
+ } else {
+ return getUpper() - 1;
+ }
+ }
+}
+
+/// getSignedMin - Return the smallest signed value contained in the
+/// ConstantRange.
+///
+APInt ConstantRange::getSignedMin() const {
+ APInt SignedMin(APInt::getSignedMinValue(getBitWidth()));
+ if (!isWrappedSet()) {
+ if (getLower().sle(getUpper() - 1))
+ return getLower();
+ else
+ return SignedMin;
+ } else {
+ if ((getUpper() - 1).slt(getLower())) {
+ if (getUpper() != SignedMin)
+ return SignedMin;
+ else
+ return getLower();
+ } else {
+ return getLower();
+ }
+ }
+}
+
+/// contains - Return true if the specified value is in the set.
+///
+bool ConstantRange::contains(const APInt &V) const {
+ if (Lower == Upper)
+ return isFullSet();
+
+ if (!isWrappedSet())
+ return Lower.ule(V) && V.ult(Upper);
+ else
+ return Lower.ule(V) || V.ult(Upper);
+}
+
+/// subtract - Subtract the specified constant from the endpoints of this
+/// constant range.
+ConstantRange ConstantRange::subtract(const APInt &Val) const {
+ assert(Val.getBitWidth() == getBitWidth() && "Wrong bit width");
+ // If the set is empty or full, don't modify the endpoints.
+ if (Lower == Upper)
+ return *this;
+ 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.
+///
+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);
+
+ 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;
+ } else {
+ 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.ult(Lower))
+ return ConstantRange(CR.Lower, Upper);
+
+ if (getSetSize().ult(CR.getSetSize()))
+ return *this;
+ else
+ return CR;
+ } else 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;
+ else
+ return CR;
+ }
+
+ if (CR.Lower.ult(Lower))
+ return ConstantRange(Lower, CR.Upper);
+
+ return CR;
+ } else if (CR.Upper.ult(Lower)) {
+ if (CR.Lower.ult(Lower))
+ return *this;
+
+ return ConstantRange(CR.Lower, Upper);
+ }
+ if (getSetSize().ult(CR.getSetSize()))
+ return *this;
+ else
+ 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);
+}
+
+/// 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 {
+ unsigned SrcTySize = getBitWidth();
+ assert(SrcTySize < DstTySize && "Not a value extension");
+ if (isFullSet())
+ // Change a source full set into [0, 1 << 8*numbytes)
+ return ConstantRange(APInt(DstTySize,0), APInt(DstTySize,1).shl(SrcTySize));
+
+ APInt L = Lower; L.zext(DstTySize);
+ APInt U = Upper; U.zext(DstTySize);
+ return ConstantRange(L, U);
+}
+
+/// 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 {
+ unsigned SrcTySize = getBitWidth();
+ assert(SrcTySize < DstTySize && "Not a value extension");
+ if (isFullSet()) {
+ return ConstantRange(APInt::getHighBitsSet(DstTySize,DstTySize-SrcTySize+1),
+ APInt::getLowBitsSet(DstTySize, SrcTySize-1));
+ }
+
+ APInt L = Lower; L.sext(DstTySize);
+ APInt U = Upper; U.sext(DstTySize);
+ return ConstantRange(L, U);
+}
+
+/// 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 {
+ unsigned SrcTySize = getBitWidth();
+ assert(SrcTySize > DstTySize && "Not a value truncation");
+ APInt Size(APInt::getLowBitsSet(SrcTySize, DstTySize));
+ if (isFullSet() || getSetSize().ugt(Size))
+ return ConstantRange(DstTySize);
+
+ APInt L = Lower; L.trunc(DstTySize);
+ APInt U = Upper; U.trunc(DstTySize);
+ return ConstantRange(L, U);
+}
+
+/// print - Print out the bounds to a stream...
+///
+void ConstantRange::print(std::ostream &OS) const {
+ OS << "[" << Lower.toStringSigned(10) << ","
+ << Upper.toStringSigned(10) << " )";
+}
+
+/// dump - Allow printing from a debugger easily...
+///
+void ConstantRange::dump() const {
+ print(cerr);
+}