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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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package org.graalvm.compiler.lir.alloc.lsra;
Represents a range of integers from a start (inclusive) to an end (exclusive.
/**
* Represents a range of integers from a start (inclusive) to an end (exclusive.
*/
public final class Range {
public static final Range EndMarker = new Range(Integer.MAX_VALUE, Integer.MAX_VALUE, null);
The start of the range, inclusive.
/**
* The start of the range, inclusive.
*/
public int from;
The end of the range, exclusive.
/**
* The end of the range, exclusive.
*/
public int to;
A link to allow the range to be put into a singly linked list.
/**
* A link to allow the range to be put into a singly linked list.
*/
public Range next;
boolean intersects(Range r) {
return intersectsAt(r) != -1;
}
Creates a new range.
Params: - from – the start of the range, inclusive
- to – the end of the range, exclusive
- next – link to the next range in a linked list
/**
* Creates a new range.
*
* @param from the start of the range, inclusive
* @param to the end of the range, exclusive
* @param next link to the next range in a linked list
*/
Range(int from, int to, Range next) {
this.from = from;
this.to = to;
this.next = next;
}
int intersectsAt(Range other) {
Range r1 = this;
Range r2 = other;
assert r2 != null : "null ranges not allowed";
assert r1 != EndMarker && r2 != EndMarker : "empty ranges not allowed";
do {
if (r1.from < r2.from) {
if (r1.to <= r2.from) {
r1 = r1.next;
if (r1 == EndMarker) {
return -1;
}
} else {
return r2.from;
}
} else {
if (r2.from < r1.from) {
if (r2.to <= r1.from) {
r2 = r2.next;
if (r2 == EndMarker) {
return -1;
}
} else {
return r1.from;
}
} else { // r1.from() == r2.from()
if (r1.from == r1.to) {
r1 = r1.next;
if (r1 == EndMarker) {
return -1;
}
} else {
if (r2.from == r2.to) {
r2 = r2.next;
if (r2 == EndMarker) {
return -1;
}
} else {
return r1.from;
}
}
}
}
} while (true);
}
@Override
public String toString() {
return "[" + from + ", " + to + "]";
}
}