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-rw-r--r--lib/Support/ConstantRange.cpp48
1 files changed, 5 insertions, 43 deletions
diff --git a/lib/Support/ConstantRange.cpp b/lib/Support/ConstantRange.cpp
index 4cb54bde1b..5f3d6f8db2 100644
--- a/lib/Support/ConstantRange.cpp
+++ b/lib/Support/ConstantRange.cpp
@@ -275,58 +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()) {
- 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!");
// 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)) {