/*
* Copyright (c) 2009, 2015, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* 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).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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*/
package org.graalvm.compiler.core.common.calc;
import org.graalvm.compiler.debug.GraalError;
import jdk.vm.ci.meta.Constant;
import jdk.vm.ci.meta.ConstantReflectionProvider;
import jdk.vm.ci.meta.JavaConstant;
import jdk.vm.ci.meta.PrimitiveConstant;
/**
* Condition codes used in conditionals.
*/
public enum Condition {
/**
* Equal.
*/
EQ("=="),
/**
* Not equal.
*/
NE("!="),
/**
* Signed less than.
*/
LT("<"),
/**
* Signed less than or equal.
*/
LE("<="),
/**
* Signed greater than.
*/
GT(">"),
/**
* Signed greater than or equal.
*/
GE(">="),
/**
* Unsigned greater than or equal ("above than or equal").
*/
AE("|>=|"),
/**
* Unsigned less than or equal ("below than or equal").
*/
BE("|<=|"),
/**
* Unsigned greater than ("above than").
*/
AT("|>|"),
/**
* Unsigned less than ("below than").
*/
BT("|<|");
public final String operator;
Condition(String operator) {
this.operator = operator;
}
public boolean check(int left, int right) {
switch (this) {
case EQ:
return left == right;
case NE:
return left != right;
case LT:
return left < right;
case LE:
return left <= right;
case GT:
return left > right;
case GE:
return left >= right;
case AE:
return UnsignedMath.aboveOrEqual(left, right);
case BE:
return UnsignedMath.belowOrEqual(left, right);
case AT:
return UnsignedMath.aboveThan(left, right);
case BT:
return UnsignedMath.belowThan(left, right);
}
throw new IllegalArgumentException(this.toString());
}
/**
* Given a condition and its negation, this method returns true for one of the two and false for
* the other one. This can be used to keep comparisons in a canonical form.
*
* @return true if this condition is considered to be the canonical form, false otherwise.
*/
public boolean isCanonical() {
switch (this) {
case EQ:
return true;
case NE:
return false;
case LT:
return true;
case LE:
return false;
case GT:
return false;
case GE:
return false;
case BT:
return true;
case BE:
return false;
case AT:
return false;
case AE:
return false;
}
throw new IllegalArgumentException(this.toString());
}
/**
* Returns true if the condition needs to be mirrored to get to a canonical condition. The
* result of the mirroring operation might still need to be negated to achieve a canonical form.
*/
public boolean canonicalMirror() {
switch (this) {
case EQ:
return false;
case NE:
return false;
case LT:
return false;
case LE:
return true;
case GT:
return true;
case GE:
return false;
case BT:
return false;
case BE:
return true;
case AT:
return true;
case AE:
return false;
}
throw new IllegalArgumentException(this.toString());
}
/**
* Returns true if the condition needs to be negated to get to a canonical condition. The result
* of the negation might still need to be mirrored to achieve a canonical form.
*/
public boolean canonicalNegate() {
switch (this) {
case EQ:
return false;
case NE:
return true;
case LT:
return false;
case LE:
return true;
case GT:
return false;
case GE:
return true;
case BT:
return false;
case BE:
return true;
case AT:
return false;
case AE:
return true;
}
throw new IllegalArgumentException(this.toString());
}
/**
* Negate this conditional.
*
* @return the condition that represents the negation
*/
public final Condition negate() {
switch (this) {
case EQ:
return NE;
case NE:
return EQ;
case LT:
return GE;
case LE:
return GT;
case GT:
return LE;
case GE:
return LT;
case BT:
return AE;
case BE:
return AT;
case AT:
return BE;
case AE:
return BT;
}
throw new IllegalArgumentException(this.toString());
}
public boolean implies(Condition other) {
if (other == this) {
return true;
}
switch (this) {
case EQ:
return other == LE || other == GE || other == BE || other == AE;
case NE:
return false;
case LT:
return other == LE || other == NE;
case LE:
return false;
case GT:
return other == GE || other == NE;
case GE:
return false;
case BT:
return other == BE || other == NE;
case BE:
return false;
case AT:
return other == AE || other == NE;
case AE:
return false;
}
throw new IllegalArgumentException(this.toString());
}
/**
* Mirror this conditional (i.e. commute "a op b" to "b op' a")
*
* @return the condition representing the equivalent commuted operation
*/
public final Condition mirror() {
switch (this) {
case EQ:
return EQ;
case NE:
return NE;
case LT:
return GT;
case LE:
return GE;
case GT:
return LT;
case GE:
return LE;
case BT:
return AT;
case BE:
return AE;
case AT:
return BT;
case AE:
return BE;
}
throw new IllegalArgumentException();
}
/**
* Returns true if this condition represents an unsigned comparison. EQ and NE are not
* considered to be unsigned.
*/
public final boolean isUnsigned() {
return this == Condition.BT || this == Condition.BE || this == Condition.AT || this == Condition.AE;
}
/**
* Checks if this conditional operation is commutative.
*
* @return {@code true} if this operation is commutative
*/
public final boolean isCommutative() {
return this == EQ || this == NE;
}
/**
* Attempts to fold a comparison between two constants and return the result.
*
* @param lt the constant on the left side of the comparison
* @param rt the constant on the right side of the comparison
* @param constantReflection needed to compare constants
* @return {@link Boolean#TRUE} if the comparison is known to be true, {@link Boolean#FALSE} if
* the comparison is known to be false
*/
public boolean foldCondition(JavaConstant lt, JavaConstant rt, ConstantReflectionProvider constantReflection) {
assert !lt.getJavaKind().isNumericFloat() && !rt.getJavaKind().isNumericFloat();
return foldCondition(lt, rt, constantReflection, false);
}
/**
* Attempts to fold a comparison between two constants and return the result.
*
* @param lt the constant on the left side of the comparison
* @param rt the constant on the right side of the comparison
* @param constantReflection needed to compare constants
* @param unorderedIsTrue true if an undecided float comparison should result in "true"
* @return true if the comparison is known to be true, false if the comparison is known to be
* false
*/
public boolean foldCondition(Constant lt, Constant rt, ConstantReflectionProvider constantReflection, boolean unorderedIsTrue) {
if (lt instanceof PrimitiveConstant) {
PrimitiveConstant lp = (PrimitiveConstant) lt;
PrimitiveConstant rp = (PrimitiveConstant) rt;
return foldCondition(lp, rp, unorderedIsTrue);
} else {
Boolean equal = constantReflection.constantEquals(lt, rt);
if (equal == null) {
throw new GraalError("could not fold %s %s %s", lt, this, rt);
}
switch (this) {
case EQ:
return equal.booleanValue();
case NE:
return !equal.booleanValue();
default:
throw new GraalError("expected condition: %s", this);
}
}
}
/**
* Attempts to fold a comparison between two primitive constants and return the result.
*
* @param lp the constant on the left side of the comparison
* @param rp the constant on the right side of the comparison
* @param unorderedIsTrue true if an undecided float comparison should result in "true"
* @return true if the comparison is known to be true, false if the comparison is known to be
* false
*/
public boolean foldCondition(PrimitiveConstant lp, PrimitiveConstant rp, boolean unorderedIsTrue) {
switch (lp.getJavaKind()) {
case Boolean:
case Byte:
case Char:
case Short:
case Int: {
int x = lp.asInt();
int y = rp.asInt();
switch (this) {
case EQ:
return x == y;
case NE:
return x != y;
case LT:
return x < y;
case LE:
return x <= y;
case GT:
return x > y;
case GE:
return x >= y;
case AE:
return UnsignedMath.aboveOrEqual(x, y);
case BE:
return UnsignedMath.belowOrEqual(x, y);
case AT:
return UnsignedMath.aboveThan(x, y);
case BT:
return UnsignedMath.belowThan(x, y);
default:
throw new GraalError("expected condition: %s", this);
}
}
case Long: {
long x = lp.asLong();
long y = rp.asLong();
switch (this) {
case EQ:
return x == y;
case NE:
return x != y;
case LT:
return x < y;
case LE:
return x <= y;
case GT:
return x > y;
case GE:
return x >= y;
case AE:
return UnsignedMath.aboveOrEqual(x, y);
case BE:
return UnsignedMath.belowOrEqual(x, y);
case AT:
return UnsignedMath.aboveThan(x, y);
case BT:
return UnsignedMath.belowThan(x, y);
default:
throw new GraalError("expected condition: %s", this);
}
}
case Float: {
float x = lp.asFloat();
float y = rp.asFloat();
if (Float.isNaN(x) || Float.isNaN(y)) {
return unorderedIsTrue;
}
switch (this) {
case EQ:
return x == y;
case NE:
return x != y;
case LT:
return x < y;
case LE:
return x <= y;
case GT:
return x > y;
case GE:
return x >= y;
default:
throw new GraalError("expected condition: %s", this);
}
}
case Double: {
double x = lp.asDouble();
double y = rp.asDouble();
if (Double.isNaN(x) || Double.isNaN(y)) {
return unorderedIsTrue;
}
switch (this) {
case EQ:
return x == y;
case NE:
return x != y;
case LT:
return x < y;
case LE:
return x <= y;
case GT:
return x > y;
case GE:
return x >= y;
default:
throw new GraalError("expected condition: %s", this);
}
}
default:
throw new GraalError("expected value kind %s while folding condition: %s", lp.getJavaKind(), this);
}
}
public Condition join(Condition other) {
if (other == this) {
return this;
}
switch (this) {
case EQ:
if (other == LE || other == GE || other == BE || other == AE) {
return EQ;
} else {
return null;
}
case NE:
if (other == LT || other == GT || other == BT || other == AT) {
return other;
} else if (other == LE) {
return LT;
} else if (other == GE) {
return GT;
} else if (other == BE) {
return BT;
} else if (other == AE) {
return AT;
} else {
return null;
}
case LE:
if (other == GE || other == EQ) {
return EQ;
} else if (other == NE || other == LT) {
return LT;
} else {
return null;
}
case LT:
if (other == NE || other == LE) {
return LT;
} else {
return null;
}
case GE:
if (other == LE || other == EQ) {
return EQ;
} else if (other == NE || other == GT) {
return GT;
} else {
return null;
}
case GT:
if (other == NE || other == GE) {
return GT;
} else {
return null;
}
case BE:
if (other == AE || other == EQ) {
return EQ;
} else if (other == NE || other == BT) {
return BT;
} else {
return null;
}
case BT:
if (other == NE || other == BE) {
return BT;
} else {
return null;
}
case AE:
if (other == BE || other == EQ) {
return EQ;
} else if (other == NE || other == AT) {
return AT;
} else {
return null;
}
case AT:
if (other == NE || other == AE) {
return AT;
} else {
return null;
}
}
throw new IllegalArgumentException(this.toString());
}
public Condition meet(Condition other) {
if (other == this) {
return this;
}
switch (this) {
case EQ:
if (other == LE || other == GE || other == BE || other == AE) {
return other;
} else if (other == LT) {
return LE;
} else if (other == GT) {
return GE;
} else if (other == BT) {
return BE;
} else if (other == AT) {
return AE;
} else {
return null;
}
case NE:
if (other == LT || other == GT || other == BT || other == AT) {
return NE;
} else {
return null;
}
case LE:
if (other == EQ || other == LT) {
return LE;
} else {
return null;
}
case LT:
if (other == EQ || other == LE) {
return LE;
} else if (other == NE || other == GT) {
return NE;
} else {
return null;
}
case GE:
if (other == EQ || other == GT) {
return GE;
} else {
return null;
}
case GT:
if (other == EQ || other == GE) {
return GE;
} else if (other == NE || other == LT) {
return NE;
} else {
return null;
}
case BE:
if (other == EQ || other == BT) {
return BE;
} else {
return null;
}
case BT:
if (other == EQ || other == BE) {
return BE;
} else if (other == NE || other == AT) {
return NE;
} else {
return null;
}
case AE:
if (other == EQ || other == AT) {
return AE;
} else {
return null;
}
case AT:
if (other == EQ || other == AE) {
return AE;
} else if (other == NE || other == BT) {
return NE;
} else {
return null;
}
}
throw new IllegalArgumentException(this.toString());
}
}