src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.core.common/src/org/graalvm/compiler/core/common/type/IntegerStamp.java
changeset 47216 71c04702a3d5
parent 46963 089674d9949b
child 47798 9fe9292f5931
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.core.common/src/org/graalvm/compiler/core/common/type/IntegerStamp.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,1556 @@
+/*
+ * Copyright (c) 2012, 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
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package org.graalvm.compiler.core.common.type;
+
+import static org.graalvm.compiler.core.common.calc.FloatConvert.I2D;
+import static org.graalvm.compiler.core.common.calc.FloatConvert.I2F;
+import static org.graalvm.compiler.core.common.calc.FloatConvert.L2D;
+import static org.graalvm.compiler.core.common.calc.FloatConvert.L2F;
+
+import java.nio.ByteBuffer;
+import java.util.Formatter;
+
+import org.graalvm.compiler.core.common.LIRKind;
+import org.graalvm.compiler.core.common.NumUtil;
+import org.graalvm.compiler.core.common.spi.LIRKindTool;
+import org.graalvm.compiler.core.common.type.ArithmeticOpTable.BinaryOp;
+import org.graalvm.compiler.core.common.type.ArithmeticOpTable.FloatConvertOp;
+import org.graalvm.compiler.core.common.type.ArithmeticOpTable.IntegerConvertOp;
+import org.graalvm.compiler.core.common.type.ArithmeticOpTable.ShiftOp;
+import org.graalvm.compiler.core.common.type.ArithmeticOpTable.UnaryOp;
+import org.graalvm.compiler.debug.GraalError;
+
+import jdk.vm.ci.code.CodeUtil;
+import jdk.vm.ci.meta.Constant;
+import jdk.vm.ci.meta.JavaConstant;
+import jdk.vm.ci.meta.JavaKind;
+import jdk.vm.ci.meta.MetaAccessProvider;
+import jdk.vm.ci.meta.PrimitiveConstant;
+import jdk.vm.ci.meta.ResolvedJavaType;
+import jdk.vm.ci.meta.SerializableConstant;
+
+/**
+ * Describes the possible values of a node that produces an int or long result.
+ *
+ * The description consists of (inclusive) lower and upper bounds and up (may be set) and down
+ * (always set) bit-masks.
+ */
+public final class IntegerStamp extends PrimitiveStamp {
+
+    private final long lowerBound;
+    private final long upperBound;
+    private final long downMask;
+    private final long upMask;
+
+    private IntegerStamp(int bits, long lowerBound, long upperBound, long downMask, long upMask) {
+        super(bits, OPS);
+
+        this.lowerBound = lowerBound;
+        this.upperBound = upperBound;
+        this.downMask = downMask;
+        this.upMask = upMask;
+
+        assert lowerBound >= CodeUtil.minValue(bits) : this;
+        assert upperBound <= CodeUtil.maxValue(bits) : this;
+        assert (downMask & CodeUtil.mask(bits)) == downMask : this;
+        assert (upMask & CodeUtil.mask(bits)) == upMask : this;
+    }
+
+    public static IntegerStamp create(int bits, long lowerBoundInput, long upperBoundInput) {
+        return create(bits, lowerBoundInput, upperBoundInput, 0, CodeUtil.mask(bits));
+    }
+
+    public static IntegerStamp create(int bits, long lowerBoundInput, long upperBoundInput, long downMask, long upMask) {
+        assert (downMask & ~upMask) == 0 : String.format("\u21ca: %016x \u21c8: %016x", downMask, upMask);
+
+        // Set lower bound, use masks to make it more precise
+        long minValue = minValueForMasks(bits, downMask, upMask);
+        long lowerBoundTmp = Math.max(lowerBoundInput, minValue);
+
+        // Set upper bound, use masks to make it more precise
+        long maxValue = maxValueForMasks(bits, downMask, upMask);
+        long upperBoundTmp = Math.min(upperBoundInput, maxValue);
+
+        // Assign masks now with the bounds in mind.
+        final long boundedDownMask;
+        final long boundedUpMask;
+        long defaultMask = CodeUtil.mask(bits);
+        if (lowerBoundTmp == upperBoundTmp) {
+            boundedDownMask = lowerBoundTmp;
+            boundedUpMask = lowerBoundTmp;
+        } else if (lowerBoundTmp >= 0) {
+            int upperBoundLeadingZeros = Long.numberOfLeadingZeros(upperBoundTmp);
+            long differentBits = lowerBoundTmp ^ upperBoundTmp;
+            int sameBitCount = Long.numberOfLeadingZeros(differentBits << upperBoundLeadingZeros);
+
+            boundedUpMask = upperBoundTmp | -1L >>> (upperBoundLeadingZeros + sameBitCount);
+            boundedDownMask = upperBoundTmp & ~(-1L >>> (upperBoundLeadingZeros + sameBitCount));
+        } else {
+            if (upperBoundTmp >= 0) {
+                boundedUpMask = defaultMask;
+                boundedDownMask = 0;
+            } else {
+                int lowerBoundLeadingOnes = Long.numberOfLeadingZeros(~lowerBoundTmp);
+                long differentBits = lowerBoundTmp ^ upperBoundTmp;
+                int sameBitCount = Long.numberOfLeadingZeros(differentBits << lowerBoundLeadingOnes);
+
+                boundedUpMask = lowerBoundTmp | -1L >>> (lowerBoundLeadingOnes + sameBitCount) | ~(-1L >>> lowerBoundLeadingOnes);
+                boundedDownMask = lowerBoundTmp & ~(-1L >>> (lowerBoundLeadingOnes + sameBitCount)) | ~(-1L >>> lowerBoundLeadingOnes);
+            }
+        }
+
+        return new IntegerStamp(bits, lowerBoundTmp, upperBoundTmp, defaultMask & (downMask | boundedDownMask), defaultMask & upMask & boundedUpMask);
+    }
+
+    static long significantBit(long bits, long value) {
+        return (value >>> (bits - 1)) & 1;
+    }
+
+    static long minValueForMasks(int bits, long downMask, long upMask) {
+        if (significantBit(bits, upMask) == 0) {
+            // Value is always positive. Minimum value always positive.
+            assert significantBit(bits, downMask) == 0;
+            return downMask;
+        } else {
+            // Value can be positive or negative. Minimum value always negative.
+            return downMask | (-1L << (bits - 1));
+        }
+    }
+
+    static long maxValueForMasks(int bits, long downMask, long upMask) {
+        if (significantBit(bits, downMask) == 1) {
+            // Value is always negative. Maximum value always negative.
+            assert significantBit(bits, upMask) == 1;
+            return CodeUtil.signExtend(upMask, bits);
+        } else {
+            // Value can be positive or negative. Maximum value always positive.
+            return upMask & (CodeUtil.mask(bits) >>> 1);
+        }
+    }
+
+    public static IntegerStamp stampForMask(int bits, long downMask, long upMask) {
+        return new IntegerStamp(bits, minValueForMasks(bits, downMask, upMask), maxValueForMasks(bits, downMask, upMask), downMask, upMask);
+    }
+
+    @Override
+    public IntegerStamp unrestricted() {
+        return new IntegerStamp(getBits(), CodeUtil.minValue(getBits()), CodeUtil.maxValue(getBits()), 0, CodeUtil.mask(getBits()));
+    }
+
+    @Override
+    public IntegerStamp empty() {
+        return new IntegerStamp(getBits(), CodeUtil.maxValue(getBits()), CodeUtil.minValue(getBits()), CodeUtil.mask(getBits()), 0);
+    }
+
+    @Override
+    public Stamp constant(Constant c, MetaAccessProvider meta) {
+        if (c instanceof PrimitiveConstant) {
+            long value = ((PrimitiveConstant) c).asLong();
+            return StampFactory.forInteger(getBits(), value, value);
+        }
+        return this;
+    }
+
+    @Override
+    public SerializableConstant deserialize(ByteBuffer buffer) {
+        switch (getBits()) {
+            case 1:
+                return JavaConstant.forBoolean(buffer.get() != 0);
+            case 8:
+                return JavaConstant.forByte(buffer.get());
+            case 16:
+                return JavaConstant.forShort(buffer.getShort());
+            case 32:
+                return JavaConstant.forInt(buffer.getInt());
+            case 64:
+                return JavaConstant.forLong(buffer.getLong());
+            default:
+                throw GraalError.shouldNotReachHere();
+        }
+    }
+
+    @Override
+    public boolean hasValues() {
+        return lowerBound <= upperBound;
+    }
+
+    @Override
+    public JavaKind getStackKind() {
+        if (getBits() > 32) {
+            return JavaKind.Long;
+        } else {
+            return JavaKind.Int;
+        }
+    }
+
+    @Override
+    public LIRKind getLIRKind(LIRKindTool tool) {
+        return tool.getIntegerKind(getBits());
+    }
+
+    @Override
+    public ResolvedJavaType javaType(MetaAccessProvider metaAccess) {
+        switch (getBits()) {
+            case 1:
+                return metaAccess.lookupJavaType(Boolean.TYPE);
+            case 8:
+                return metaAccess.lookupJavaType(Byte.TYPE);
+            case 16:
+                return metaAccess.lookupJavaType(Short.TYPE);
+            case 32:
+                return metaAccess.lookupJavaType(Integer.TYPE);
+            case 64:
+                return metaAccess.lookupJavaType(Long.TYPE);
+            default:
+                throw GraalError.shouldNotReachHere();
+        }
+    }
+
+    /**
+     * The signed inclusive lower bound on the value described by this stamp.
+     */
+    public long lowerBound() {
+        return lowerBound;
+    }
+
+    /**
+     * The signed inclusive upper bound on the value described by this stamp.
+     */
+    public long upperBound() {
+        return upperBound;
+    }
+
+    /**
+     * This bit-mask describes the bits that are always set in the value described by this stamp.
+     */
+    public long downMask() {
+        return downMask;
+    }
+
+    /**
+     * This bit-mask describes the bits that can be set in the value described by this stamp.
+     */
+    public long upMask() {
+        return upMask;
+    }
+
+    @Override
+    public boolean isUnrestricted() {
+        return lowerBound == CodeUtil.minValue(getBits()) && upperBound == CodeUtil.maxValue(getBits()) && downMask == 0 && upMask == CodeUtil.mask(getBits());
+    }
+
+    public boolean contains(long value) {
+        return value >= lowerBound && value <= upperBound && (value & downMask) == downMask && (value & upMask) == (value & CodeUtil.mask(getBits()));
+    }
+
+    public boolean isPositive() {
+        return lowerBound() >= 0;
+    }
+
+    public boolean isNegative() {
+        return upperBound() <= 0;
+    }
+
+    public boolean isStrictlyPositive() {
+        return lowerBound() > 0;
+    }
+
+    public boolean isStrictlyNegative() {
+        return upperBound() < 0;
+    }
+
+    public boolean canBePositive() {
+        return upperBound() > 0;
+    }
+
+    public boolean canBeNegative() {
+        return lowerBound() < 0;
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder str = new StringBuilder();
+        str.append('i');
+        str.append(getBits());
+        if (hasValues()) {
+            if (lowerBound == upperBound) {
+                str.append(" [").append(lowerBound).append(']');
+            } else if (lowerBound != CodeUtil.minValue(getBits()) || upperBound != CodeUtil.maxValue(getBits())) {
+                str.append(" [").append(lowerBound).append(" - ").append(upperBound).append(']');
+            }
+            if (downMask != 0) {
+                str.append(" \u21ca");
+                new Formatter(str).format("%016x", downMask);
+            }
+            if (upMask != CodeUtil.mask(getBits())) {
+                str.append(" \u21c8");
+                new Formatter(str).format("%016x", upMask);
+            }
+        } else {
+            str.append("<empty>");
+        }
+        return str.toString();
+    }
+
+    private IntegerStamp createStamp(IntegerStamp other, long newUpperBound, long newLowerBound, long newDownMask, long newUpMask) {
+        assert getBits() == other.getBits();
+        if (newLowerBound > newUpperBound || (newDownMask & (~newUpMask)) != 0 || (newUpMask == 0 && (newLowerBound > 0 || newUpperBound < 0))) {
+            return empty();
+        } else if (newLowerBound == lowerBound && newUpperBound == upperBound && newDownMask == downMask && newUpMask == upMask) {
+            return this;
+        } else if (newLowerBound == other.lowerBound && newUpperBound == other.upperBound && newDownMask == other.downMask && newUpMask == other.upMask) {
+            return other;
+        } else {
+            return IntegerStamp.create(getBits(), newLowerBound, newUpperBound, newDownMask, newUpMask);
+        }
+    }
+
+    @Override
+    public Stamp meet(Stamp otherStamp) {
+        if (otherStamp == this) {
+            return this;
+        }
+        IntegerStamp other = (IntegerStamp) otherStamp;
+        return createStamp(other, Math.max(upperBound, other.upperBound), Math.min(lowerBound, other.lowerBound), downMask & other.downMask, upMask | other.upMask);
+    }
+
+    @Override
+    public IntegerStamp join(Stamp otherStamp) {
+        if (otherStamp == this) {
+            return this;
+        }
+        IntegerStamp other = (IntegerStamp) otherStamp;
+        long newDownMask = downMask | other.downMask;
+        long newLowerBound = Math.max(lowerBound, other.lowerBound);
+        long newUpperBound = Math.min(upperBound, other.upperBound);
+        long newUpMask = upMask & other.upMask;
+        return createStamp(other, newUpperBound, newLowerBound, newDownMask, newUpMask);
+    }
+
+    @Override
+    public boolean isCompatible(Stamp stamp) {
+        if (this == stamp) {
+            return true;
+        }
+        if (stamp instanceof IntegerStamp) {
+            IntegerStamp other = (IntegerStamp) stamp;
+            return getBits() == other.getBits();
+        }
+        return false;
+    }
+
+    @Override
+    public boolean isCompatible(Constant constant) {
+        if (constant instanceof PrimitiveConstant) {
+            PrimitiveConstant prim = (PrimitiveConstant) constant;
+            return prim.getJavaKind().isNumericInteger();
+        }
+        return false;
+    }
+
+    public long unsignedUpperBound() {
+        if (sameSignBounds()) {
+            return CodeUtil.zeroExtend(upperBound(), getBits());
+        }
+        return NumUtil.maxValueUnsigned(getBits());
+    }
+
+    public long unsignedLowerBound() {
+        if (sameSignBounds()) {
+            return CodeUtil.zeroExtend(lowerBound(), getBits());
+        }
+        return 0;
+    }
+
+    private boolean sameSignBounds() {
+        return NumUtil.sameSign(lowerBound, upperBound);
+    }
+
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+        result = prime * result + super.hashCode();
+        result = prime * result + (int) (lowerBound ^ (lowerBound >>> 32));
+        result = prime * result + (int) (upperBound ^ (upperBound >>> 32));
+        result = prime * result + (int) (downMask ^ (downMask >>> 32));
+        result = prime * result + (int) (upMask ^ (upMask >>> 32));
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+        if (obj == null || getClass() != obj.getClass() || !super.equals(obj)) {
+            return false;
+        }
+        IntegerStamp other = (IntegerStamp) obj;
+        if (lowerBound != other.lowerBound || upperBound != other.upperBound || downMask != other.downMask || upMask != other.upMask) {
+            return false;
+        }
+        return super.equals(other);
+    }
+
+    public static long upMaskFor(int bits, long lowerBound, long upperBound) {
+        long mask = lowerBound | upperBound;
+        if (mask == 0) {
+            return 0;
+        } else {
+            return ((-1L) >>> Long.numberOfLeadingZeros(mask)) & CodeUtil.mask(bits);
+        }
+    }
+
+    /**
+     * Checks if the 2 stamps represent values of the same sign. Returns true if the two stamps are
+     * both positive of null or if they are both strictly negative
+     *
+     * @return true if the two stamps are both positive of null or if they are both strictly
+     *         negative
+     */
+    public static boolean sameSign(IntegerStamp s1, IntegerStamp s2) {
+        return s1.isPositive() && s2.isPositive() || s1.isStrictlyNegative() && s2.isStrictlyNegative();
+    }
+
+    @Override
+    public JavaConstant asConstant() {
+        if (lowerBound == upperBound) {
+            switch (getBits()) {
+                case 1:
+                    return JavaConstant.forBoolean(lowerBound != 0);
+                case 8:
+                    return JavaConstant.forByte((byte) lowerBound);
+                case 16:
+                    return JavaConstant.forShort((short) lowerBound);
+                case 32:
+                    return JavaConstant.forInt((int) lowerBound);
+                case 64:
+                    return JavaConstant.forLong(lowerBound);
+            }
+        }
+        return null;
+    }
+
+    public static boolean addCanOverflow(IntegerStamp a, IntegerStamp b) {
+        assert a.getBits() == b.getBits();
+        return addOverflowsPositively(a.upperBound(), b.upperBound(), a.getBits()) ||
+                        addOverflowsNegatively(a.lowerBound(), b.lowerBound(), a.getBits());
+
+    }
+
+    public static boolean addOverflowsPositively(long x, long y, int bits) {
+        long result = x + y;
+        if (bits == 64) {
+            return (~x & ~y & result) < 0;
+        } else {
+            return result > CodeUtil.maxValue(bits);
+        }
+    }
+
+    public static boolean addOverflowsNegatively(long x, long y, int bits) {
+        long result = x + y;
+        if (bits == 64) {
+            return (x & y & ~result) < 0;
+        } else {
+            return result < CodeUtil.minValue(bits);
+        }
+    }
+
+    public static long carryBits(long x, long y) {
+        return (x + y) ^ x ^ y;
+    }
+
+    private static long saturate(long v, int bits) {
+        if (bits < 64) {
+            long max = CodeUtil.maxValue(bits);
+            if (v > max) {
+                return max;
+            }
+            long min = CodeUtil.minValue(bits);
+            if (v < min) {
+                return min;
+            }
+        }
+        return v;
+    }
+
+    public static boolean multiplicationOverflows(long a, long b, int bits) {
+        assert bits <= 64 && bits >= 0;
+        long result = a * b;
+        // result is positive if the sign is the same
+        boolean positive = (a >= 0 && b >= 0) || (a < 0 && b < 0);
+        if (bits == 64) {
+            if (a > 0 && b > 0) {
+                return a > 0x7FFFFFFF_FFFFFFFFL / b;
+            } else if (a > 0 && b <= 0) {
+                return b < 0x80000000_00000000L / a;
+            } else if (a <= 0 && b > 0) {
+                return a < 0x80000000_00000000L / b;
+            } else {
+                // a<=0 && b <=0
+                return a != 0 && b < 0x7FFFFFFF_FFFFFFFFL / a;
+            }
+        } else {
+            if (positive) {
+                return result > CodeUtil.maxValue(bits);
+            } else {
+                return result < CodeUtil.minValue(bits);
+            }
+        }
+    }
+
+    public static boolean multiplicationCanOverflow(IntegerStamp a, IntegerStamp b) {
+        // see IntegerStamp#foldStamp for details
+        assert a.getBits() == b.getBits();
+        if (a.upMask() == 0) {
+            return false;
+        } else if (b.upMask() == 0) {
+            return false;
+        }
+        if (a.isUnrestricted()) {
+            return true;
+        }
+        if (b.isUnrestricted()) {
+            return true;
+        }
+        int bits = a.getBits();
+        long minNegA = a.lowerBound();
+        long maxNegA = Math.min(0, a.upperBound());
+        long minPosA = Math.max(0, a.lowerBound());
+        long maxPosA = a.upperBound();
+
+        long minNegB = b.lowerBound();
+        long maxNegB = Math.min(0, b.upperBound());
+        long minPosB = Math.max(0, b.lowerBound());
+        long maxPosB = b.upperBound();
+
+        boolean mayOverflow = false;
+        if (a.canBePositive()) {
+            if (b.canBePositive()) {
+                mayOverflow |= IntegerStamp.multiplicationOverflows(maxPosA, maxPosB, bits);
+                mayOverflow |= IntegerStamp.multiplicationOverflows(minPosA, minPosB, bits);
+            }
+            if (b.canBeNegative()) {
+                mayOverflow |= IntegerStamp.multiplicationOverflows(minPosA, maxNegB, bits);
+                mayOverflow |= IntegerStamp.multiplicationOverflows(maxPosA, minNegB, bits);
+
+            }
+        }
+        if (a.canBeNegative()) {
+            if (b.canBePositive()) {
+                mayOverflow |= IntegerStamp.multiplicationOverflows(maxNegA, minPosB, bits);
+                mayOverflow |= IntegerStamp.multiplicationOverflows(minNegA, maxPosB, bits);
+            }
+            if (b.canBeNegative()) {
+                mayOverflow |= IntegerStamp.multiplicationOverflows(minNegA, minNegB, bits);
+                mayOverflow |= IntegerStamp.multiplicationOverflows(maxNegA, maxNegB, bits);
+            }
+        }
+        return mayOverflow;
+    }
+
+    public static boolean subtractionCanOverflow(IntegerStamp x, IntegerStamp y) {
+        assert x.getBits() == y.getBits();
+        return subtractionOverflows(x.lowerBound(), y.upperBound(), x.getBits()) || subtractionOverflows(x.upperBound(), y.lowerBound(), x.getBits());
+    }
+
+    public static boolean subtractionOverflows(long x, long y, int bits) {
+        long result = x - y;
+        if (bits == 64) {
+            return (((x ^ y) & (x ^ result)) < 0);
+        }
+        return result < CodeUtil.minValue(bits) || result > CodeUtil.maxValue(bits);
+    }
+
+    public static final ArithmeticOpTable OPS = new ArithmeticOpTable(
+
+                    new UnaryOp.Neg() {
+
+                        @Override
+                        public Constant foldConstant(Constant value) {
+                            PrimitiveConstant c = (PrimitiveConstant) value;
+                            return JavaConstant.forIntegerKind(c.getJavaKind(), -c.asLong());
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp s) {
+                            IntegerStamp stamp = (IntegerStamp) s;
+                            int bits = stamp.getBits();
+                            if (stamp.lowerBound() != CodeUtil.minValue(bits)) {
+                                // TODO(ls) check if the mask calculation is correct...
+                                return StampFactory.forInteger(bits, -stamp.upperBound(), -stamp.lowerBound());
+                            } else {
+                                return stamp.unrestricted();
+                            }
+                        }
+                    },
+
+                    new BinaryOp.Add(true, true) {
+
+                        @Override
+                        public Constant foldConstant(Constant const1, Constant const2) {
+                            PrimitiveConstant a = (PrimitiveConstant) const1;
+                            PrimitiveConstant b = (PrimitiveConstant) const2;
+                            assert a.getJavaKind() == b.getJavaKind();
+                            return JavaConstant.forIntegerKind(a.getJavaKind(), a.asLong() + b.asLong());
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp stamp1, Stamp stamp2) {
+                            IntegerStamp a = (IntegerStamp) stamp1;
+                            IntegerStamp b = (IntegerStamp) stamp2;
+
+                            int bits = a.getBits();
+                            assert bits == b.getBits();
+
+                            if (a.isUnrestricted()) {
+                                return a;
+                            } else if (b.isUnrestricted()) {
+                                return b;
+                            }
+                            long defaultMask = CodeUtil.mask(bits);
+                            long variableBits = (a.downMask() ^ a.upMask()) | (b.downMask() ^ b.upMask());
+                            long variableBitsWithCarry = variableBits | (carryBits(a.downMask(), b.downMask()) ^ carryBits(a.upMask(), b.upMask()));
+                            long newDownMask = (a.downMask() + b.downMask()) & ~variableBitsWithCarry;
+                            long newUpMask = (a.downMask() + b.downMask()) | variableBitsWithCarry;
+
+                            newDownMask &= defaultMask;
+                            newUpMask &= defaultMask;
+
+                            long newLowerBound;
+                            long newUpperBound;
+                            boolean lowerOverflowsPositively = addOverflowsPositively(a.lowerBound(), b.lowerBound(), bits);
+                            boolean upperOverflowsPositively = addOverflowsPositively(a.upperBound(), b.upperBound(), bits);
+                            boolean lowerOverflowsNegatively = addOverflowsNegatively(a.lowerBound(), b.lowerBound(), bits);
+                            boolean upperOverflowsNegatively = addOverflowsNegatively(a.upperBound(), b.upperBound(), bits);
+                            if ((lowerOverflowsNegatively && !upperOverflowsNegatively) || (!lowerOverflowsPositively && upperOverflowsPositively)) {
+                                newLowerBound = CodeUtil.minValue(bits);
+                                newUpperBound = CodeUtil.maxValue(bits);
+                            } else {
+                                newLowerBound = CodeUtil.signExtend((a.lowerBound() + b.lowerBound()) & defaultMask, bits);
+                                newUpperBound = CodeUtil.signExtend((a.upperBound() + b.upperBound()) & defaultMask, bits);
+                            }
+                            IntegerStamp limit = StampFactory.forInteger(bits, newLowerBound, newUpperBound);
+                            newUpMask &= limit.upMask();
+                            newUpperBound = CodeUtil.signExtend(newUpperBound & newUpMask, bits);
+                            newDownMask |= limit.downMask();
+                            newLowerBound |= newDownMask;
+                            return new IntegerStamp(bits, newLowerBound, newUpperBound, newDownMask, newUpMask);
+                        }
+
+                        @Override
+                        public boolean isNeutral(Constant value) {
+                            PrimitiveConstant n = (PrimitiveConstant) value;
+                            return n.asLong() == 0;
+                        }
+                    },
+
+                    new BinaryOp.Sub(true, false) {
+
+                        @Override
+                        public Constant foldConstant(Constant const1, Constant const2) {
+                            PrimitiveConstant a = (PrimitiveConstant) const1;
+                            PrimitiveConstant b = (PrimitiveConstant) const2;
+                            assert a.getJavaKind() == b.getJavaKind();
+                            return JavaConstant.forIntegerKind(a.getJavaKind(), a.asLong() - b.asLong());
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp a, Stamp b) {
+                            return OPS.getAdd().foldStamp(a, OPS.getNeg().foldStamp(b));
+                        }
+
+                        @Override
+                        public boolean isNeutral(Constant value) {
+                            PrimitiveConstant n = (PrimitiveConstant) value;
+                            return n.asLong() == 0;
+                        }
+
+                        @Override
+                        public Constant getZero(Stamp s) {
+                            IntegerStamp stamp = (IntegerStamp) s;
+                            return JavaConstant.forPrimitiveInt(stamp.getBits(), 0);
+                        }
+                    },
+
+                    new BinaryOp.Mul(true, true) {
+
+                        @Override
+                        public Constant foldConstant(Constant const1, Constant const2) {
+                            PrimitiveConstant a = (PrimitiveConstant) const1;
+                            PrimitiveConstant b = (PrimitiveConstant) const2;
+                            assert a.getJavaKind() == b.getJavaKind();
+                            return JavaConstant.forIntegerKind(a.getJavaKind(), a.asLong() * b.asLong());
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp stamp1, Stamp stamp2) {
+                            IntegerStamp a = (IntegerStamp) stamp1;
+                            IntegerStamp b = (IntegerStamp) stamp2;
+
+                            int bits = a.getBits();
+                            assert bits == b.getBits();
+                            // if a==0 or b==0 result of a*b is always 0
+                            if (a.upMask() == 0) {
+                                return a;
+                            } else if (b.upMask() == 0) {
+                                return b;
+                            } else {
+                                // if a has the full range or b, the result will also have it
+                                if (a.isUnrestricted()) {
+                                    return a;
+                                } else if (b.isUnrestricted()) {
+                                    return b;
+                                }
+                                // a!=0 && b !=0 holds
+                                long newLowerBound = Long.MAX_VALUE;
+                                long newUpperBound = Long.MIN_VALUE;
+                                /*
+                                 * Based on the signs of the incoming stamps lower and upper bound
+                                 * of the result of the multiplication may be swapped. LowerBound
+                                 * can become upper bound if both signs are negative, and so on. To
+                                 * determine the new values for lower and upper bound we need to
+                                 * look at the max and min of the cases blow:
+                                 *
+                                 * @formatter:off
+                                 *
+                                 * a.lowerBound * b.lowerBound
+                                 * a.lowerBound * b.upperBound
+                                 * a.upperBound * b.lowerBound
+                                 * a.upperBound * b.upperBound
+                                 *
+                                 * @formatter:on
+                                 *
+                                 * We are only interested in those cases that are relevant due to
+                                 * the sign of the involved stamps (whether a stamp includes
+                                 * negative and / or positive values). Based on the signs, the maximum
+                                 * or minimum of the above multiplications form the new lower and
+                                 * upper bounds.
+                                 *
+                                 * The table below contains the interesting candidates for lower and
+                                 * upper bound after multiplication.
+                                 *
+                                 * For example if we consider two stamps a & b that both contain
+                                 * negative and positive values, the product of minNegA * minNegB
+                                 * (both the smallest negative value for each stamp) can only be the
+                                 * highest positive number. The other candidates can be computed in
+                                 * a similar fashion. Some of them can never be a new minimum or
+                                 * maximum and are therefore excluded.
+                                 *
+                                 *
+                                 * @formatter:off
+                                 *
+                                 *          [x................0................y]
+                                 *          -------------------------------------
+                                 *          [minNeg     maxNeg minPos     maxPos]
+                                 *
+                                 *          where maxNeg = min(0,y) && minPos = max(0,x)
+                                 *
+                                 *
+                                 *                 |minNegA  maxNegA    minPosA  maxPosA
+                                 *         _______ |____________________________________
+                                 *         minNegB | MAX        /     :     /      MIN
+                                 *         maxNegB |  /        MIN    :    MAX      /
+                                 *                 |------------------+-----------------
+                                 *         minPosB |  /        MAX    :    MIN      /
+                                 *         maxPosB | MIN        /     :     /      MAX
+                                 *
+                                 * @formatter:on
+                                 */
+                                // We materialize all factors here. If they are needed, the signs of
+                                // the stamp will ensure the correct value is used.
+                                long minNegA = a.lowerBound();
+                                long maxNegA = Math.min(0, a.upperBound());
+                                long minPosA = Math.max(0, a.lowerBound());
+                                long maxPosA = a.upperBound();
+
+                                long minNegB = b.lowerBound();
+                                long maxNegB = Math.min(0, b.upperBound());
+                                long minPosB = Math.max(0, b.lowerBound());
+                                long maxPosB = b.upperBound();
+
+                                // multiplication has shift semantics
+                                long newUpMask = ~CodeUtil.mask(Long.numberOfTrailingZeros(a.upMask) + Long.numberOfTrailingZeros(b.upMask)) & CodeUtil.mask(bits);
+
+                                if (a.canBePositive()) {
+                                    if (b.canBePositive()) {
+                                        if (multiplicationOverflows(maxPosA, maxPosB, bits)) {
+                                            return a.unrestricted();
+                                        }
+                                        long maxCandidate = maxPosA * maxPosB;
+                                        if (multiplicationOverflows(minPosA, minPosB, bits)) {
+                                            return a.unrestricted();
+                                        }
+                                        long minCandidate = minPosA * minPosB;
+                                        newLowerBound = Math.min(newLowerBound, minCandidate);
+                                        newUpperBound = Math.max(newUpperBound, maxCandidate);
+                                    }
+                                    if (b.canBeNegative()) {
+                                        if (multiplicationOverflows(minPosA, maxNegB, bits)) {
+                                            return a.unrestricted();
+                                        }
+                                        long maxCandidate = minPosA * maxNegB;
+                                        if (multiplicationOverflows(maxPosA, minNegB, bits)) {
+                                            return a.unrestricted();
+                                        }
+                                        long minCandidate = maxPosA * minNegB;
+                                        newLowerBound = Math.min(newLowerBound, minCandidate);
+                                        newUpperBound = Math.max(newUpperBound, maxCandidate);
+                                    }
+                                }
+                                if (a.canBeNegative()) {
+                                    if (b.canBePositive()) {
+                                        if (multiplicationOverflows(maxNegA, minPosB, bits)) {
+                                            return a.unrestricted();
+                                        }
+                                        long maxCandidate = maxNegA * minPosB;
+                                        if (multiplicationOverflows(minNegA, maxPosB, bits)) {
+                                            return a.unrestricted();
+                                        }
+                                        long minCandidate = minNegA * maxPosB;
+                                        newLowerBound = Math.min(newLowerBound, minCandidate);
+                                        newUpperBound = Math.max(newUpperBound, maxCandidate);
+                                    }
+                                    if (b.canBeNegative()) {
+                                        if (multiplicationOverflows(minNegA, minNegB, bits)) {
+                                            return a.unrestricted();
+                                        }
+                                        long maxCandidate = minNegA * minNegB;
+                                        if (multiplicationOverflows(maxNegA, maxNegB, bits)) {
+                                            return a.unrestricted();
+                                        }
+                                        long minCandidate = maxNegA * maxNegB;
+                                        newLowerBound = Math.min(newLowerBound, minCandidate);
+                                        newUpperBound = Math.max(newUpperBound, maxCandidate);
+                                    }
+                                }
+
+                                assert newLowerBound <= newUpperBound;
+                                return StampFactory.forIntegerWithMask(bits, newLowerBound, newUpperBound, 0, newUpMask);
+                            }
+                        }
+
+                        @Override
+                        public boolean isNeutral(Constant value) {
+                            PrimitiveConstant n = (PrimitiveConstant) value;
+                            return n.asLong() == 1;
+                        }
+                    },
+
+                    new BinaryOp.MulHigh(true, true) {
+
+                        @Override
+                        public Constant foldConstant(Constant const1, Constant const2) {
+                            PrimitiveConstant a = (PrimitiveConstant) const1;
+                            PrimitiveConstant b = (PrimitiveConstant) const2;
+                            assert a.getJavaKind() == b.getJavaKind();
+                            return JavaConstant.forIntegerKind(a.getJavaKind(), multiplyHigh(a.asLong(), b.asLong(), a.getJavaKind()));
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp stamp1, Stamp stamp2) {
+                            IntegerStamp a = (IntegerStamp) stamp1;
+                            IntegerStamp b = (IntegerStamp) stamp2;
+                            JavaKind javaKind = a.getStackKind();
+
+                            assert a.getBits() == b.getBits();
+                            assert javaKind == b.getStackKind();
+                            assert (javaKind == JavaKind.Int || javaKind == JavaKind.Long);
+
+                            if (a.isEmpty() || b.isEmpty()) {
+                                return a.empty();
+                            } else if (a.isUnrestricted() || b.isUnrestricted()) {
+                                return a.unrestricted();
+                            }
+
+                            long[] xExtremes = {a.lowerBound(), a.upperBound()};
+                            long[] yExtremes = {b.lowerBound(), b.upperBound()};
+                            long min = Long.MAX_VALUE;
+                            long max = Long.MIN_VALUE;
+                            for (long x : xExtremes) {
+                                for (long y : yExtremes) {
+                                    long result = multiplyHigh(x, y, javaKind);
+                                    min = Math.min(min, result);
+                                    max = Math.max(max, result);
+                                }
+                            }
+                            return StampFactory.forInteger(javaKind, min, max);
+                        }
+
+                        @Override
+                        public boolean isNeutral(Constant value) {
+                            return false;
+                        }
+
+                        private long multiplyHigh(long x, long y, JavaKind javaKind) {
+                            if (javaKind == JavaKind.Int) {
+                                return (x * y) >> 32;
+                            } else {
+                                assert javaKind == JavaKind.Long;
+                                long x0 = x & 0xFFFFFFFFL;
+                                long x1 = x >> 32;
+
+                                long y0 = y & 0xFFFFFFFFL;
+                                long y1 = y >> 32;
+
+                                long z0 = x0 * y0;
+                                long t = x1 * y0 + (z0 >>> 32);
+                                long z1 = t & 0xFFFFFFFFL;
+                                long z2 = t >> 32;
+                                z1 += x0 * y1;
+
+                                return x1 * y1 + z2 + (z1 >> 32);
+                            }
+                        }
+                    },
+
+                    new BinaryOp.UMulHigh(true, true) {
+
+                        @Override
+                        public Constant foldConstant(Constant const1, Constant const2) {
+                            PrimitiveConstant a = (PrimitiveConstant) const1;
+                            PrimitiveConstant b = (PrimitiveConstant) const2;
+                            assert a.getJavaKind() == b.getJavaKind();
+                            return JavaConstant.forIntegerKind(a.getJavaKind(), multiplyHighUnsigned(a.asLong(), b.asLong(), a.getJavaKind()));
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp stamp1, Stamp stamp2) {
+                            IntegerStamp a = (IntegerStamp) stamp1;
+                            IntegerStamp b = (IntegerStamp) stamp2;
+                            JavaKind javaKind = a.getStackKind();
+
+                            assert a.getBits() == b.getBits();
+                            assert javaKind == b.getStackKind();
+                            assert (javaKind == JavaKind.Int || javaKind == JavaKind.Long);
+
+                            if (a.isEmpty() || b.isEmpty()) {
+                                return a.empty();
+                            } else if (a.isUnrestricted() || b.isUnrestricted()) {
+                                return a.unrestricted();
+                            }
+
+                            // Note that the minima and maxima are calculated using signed min/max
+                            // functions, while the values themselves are unsigned.
+                            long[] xExtremes = getUnsignedExtremes(a);
+                            long[] yExtremes = getUnsignedExtremes(b);
+                            long min = Long.MAX_VALUE;
+                            long max = Long.MIN_VALUE;
+                            for (long x : xExtremes) {
+                                for (long y : yExtremes) {
+                                    long result = multiplyHighUnsigned(x, y, javaKind);
+                                    min = Math.min(min, result);
+                                    max = Math.max(max, result);
+                                }
+                            }
+
+                            // if min is negative, then the value can reach into the unsigned range
+                            if (min == max || min >= 0) {
+                                return StampFactory.forInteger(javaKind, min, max);
+                            } else {
+                                return StampFactory.forKind(javaKind);
+                            }
+                        }
+
+                        @Override
+                        public boolean isNeutral(Constant value) {
+                            return false;
+                        }
+
+                        private long[] getUnsignedExtremes(IntegerStamp stamp) {
+                            if (stamp.lowerBound() < 0 && stamp.upperBound() >= 0) {
+                                /*
+                                 * If -1 and 0 are both in the signed range, then we can't say
+                                 * anything about the unsigned range, so we have to return [0,
+                                 * MAX_UNSIGNED].
+                                 */
+                                return new long[]{0, -1L};
+                            } else {
+                                return new long[]{stamp.lowerBound(), stamp.upperBound()};
+                            }
+                        }
+
+                        private long multiplyHighUnsigned(long x, long y, JavaKind javaKind) {
+                            if (javaKind == JavaKind.Int) {
+                                long xl = x & 0xFFFFFFFFL;
+                                long yl = y & 0xFFFFFFFFL;
+                                long r = xl * yl;
+                                return (int) (r >>> 32);
+                            } else {
+                                assert javaKind == JavaKind.Long;
+                                long x0 = x & 0xFFFFFFFFL;
+                                long x1 = x >>> 32;
+
+                                long y0 = y & 0xFFFFFFFFL;
+                                long y1 = y >>> 32;
+
+                                long z0 = x0 * y0;
+                                long t = x1 * y0 + (z0 >>> 32);
+                                long z1 = t & 0xFFFFFFFFL;
+                                long z2 = t >>> 32;
+                                z1 += x0 * y1;
+
+                                return x1 * y1 + z2 + (z1 >>> 32);
+                            }
+                        }
+                    },
+
+                    new BinaryOp.Div(true, false) {
+
+                        @Override
+                        public Constant foldConstant(Constant const1, Constant const2) {
+                            PrimitiveConstant a = (PrimitiveConstant) const1;
+                            PrimitiveConstant b = (PrimitiveConstant) const2;
+                            assert a.getJavaKind() == b.getJavaKind();
+                            return JavaConstant.forIntegerKind(a.getJavaKind(), a.asLong() / b.asLong());
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp stamp1, Stamp stamp2) {
+                            IntegerStamp a = (IntegerStamp) stamp1;
+                            IntegerStamp b = (IntegerStamp) stamp2;
+                            assert a.getBits() == b.getBits();
+                            if (b.isStrictlyPositive()) {
+                                long newLowerBound = a.lowerBound() / b.upperBound();
+                                long newUpperBound = a.upperBound() / b.lowerBound();
+                                return StampFactory.forInteger(a.getBits(), newLowerBound, newUpperBound);
+                            } else {
+                                return a.unrestricted();
+                            }
+                        }
+
+                        @Override
+                        public boolean isNeutral(Constant value) {
+                            PrimitiveConstant n = (PrimitiveConstant) value;
+                            return n.asLong() == 1;
+                        }
+                    },
+
+                    new BinaryOp.Rem(false, false) {
+
+                        @Override
+                        public Constant foldConstant(Constant const1, Constant const2) {
+                            PrimitiveConstant a = (PrimitiveConstant) const1;
+                            PrimitiveConstant b = (PrimitiveConstant) const2;
+                            assert a.getJavaKind() == b.getJavaKind();
+                            return JavaConstant.forIntegerKind(a.getJavaKind(), a.asLong() % b.asLong());
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp stamp1, Stamp stamp2) {
+                            IntegerStamp a = (IntegerStamp) stamp1;
+                            IntegerStamp b = (IntegerStamp) stamp2;
+                            assert a.getBits() == b.getBits();
+                            // zero is always possible
+                            long newLowerBound = Math.min(a.lowerBound(), 0);
+                            long newUpperBound = Math.max(a.upperBound(), 0);
+
+                            /* the maximum absolute value of the result, derived from b */
+                            long magnitude;
+                            if (b.lowerBound() == CodeUtil.minValue(b.getBits())) {
+                                // Math.abs(...) - 1 does not work in a case
+                                magnitude = CodeUtil.maxValue(b.getBits());
+                            } else {
+                                magnitude = Math.max(Math.abs(b.lowerBound()), Math.abs(b.upperBound())) - 1;
+                            }
+                            newLowerBound = Math.max(newLowerBound, -magnitude);
+                            newUpperBound = Math.min(newUpperBound, magnitude);
+
+                            return StampFactory.forInteger(a.getBits(), newLowerBound, newUpperBound);
+                        }
+                    },
+
+                    new UnaryOp.Not() {
+
+                        @Override
+                        public Constant foldConstant(Constant c) {
+                            PrimitiveConstant value = (PrimitiveConstant) c;
+                            return JavaConstant.forIntegerKind(value.getJavaKind(), ~value.asLong());
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp stamp) {
+                            IntegerStamp integerStamp = (IntegerStamp) stamp;
+                            int bits = integerStamp.getBits();
+                            long defaultMask = CodeUtil.mask(bits);
+                            return new IntegerStamp(bits, ~integerStamp.upperBound(), ~integerStamp.lowerBound(), (~integerStamp.upMask()) & defaultMask, (~integerStamp.downMask()) & defaultMask);
+                        }
+                    },
+
+                    new BinaryOp.And(true, true) {
+
+                        @Override
+                        public Constant foldConstant(Constant const1, Constant const2) {
+                            PrimitiveConstant a = (PrimitiveConstant) const1;
+                            PrimitiveConstant b = (PrimitiveConstant) const2;
+                            assert a.getJavaKind() == b.getJavaKind();
+                            return JavaConstant.forIntegerKind(a.getJavaKind(), a.asLong() & b.asLong());
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp stamp1, Stamp stamp2) {
+                            IntegerStamp a = (IntegerStamp) stamp1;
+                            IntegerStamp b = (IntegerStamp) stamp2;
+                            assert a.getBits() == b.getBits();
+                            return stampForMask(a.getBits(), a.downMask() & b.downMask(), a.upMask() & b.upMask());
+                        }
+
+                        @Override
+                        public boolean isNeutral(Constant value) {
+                            PrimitiveConstant n = (PrimitiveConstant) value;
+                            int bits = n.getJavaKind().getBitCount();
+                            long mask = CodeUtil.mask(bits);
+                            return (n.asLong() & mask) == mask;
+                        }
+                    },
+
+                    new BinaryOp.Or(true, true) {
+
+                        @Override
+                        public Constant foldConstant(Constant const1, Constant const2) {
+                            PrimitiveConstant a = (PrimitiveConstant) const1;
+                            PrimitiveConstant b = (PrimitiveConstant) const2;
+                            assert a.getJavaKind() == b.getJavaKind();
+                            return JavaConstant.forIntegerKind(a.getJavaKind(), a.asLong() | b.asLong());
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp stamp1, Stamp stamp2) {
+                            IntegerStamp a = (IntegerStamp) stamp1;
+                            IntegerStamp b = (IntegerStamp) stamp2;
+                            assert a.getBits() == b.getBits();
+                            return stampForMask(a.getBits(), a.downMask() | b.downMask(), a.upMask() | b.upMask());
+                        }
+
+                        @Override
+                        public boolean isNeutral(Constant value) {
+                            PrimitiveConstant n = (PrimitiveConstant) value;
+                            return n.asLong() == 0;
+                        }
+                    },
+
+                    new BinaryOp.Xor(true, true) {
+
+                        @Override
+                        public Constant foldConstant(Constant const1, Constant const2) {
+                            PrimitiveConstant a = (PrimitiveConstant) const1;
+                            PrimitiveConstant b = (PrimitiveConstant) const2;
+                            assert a.getJavaKind() == b.getJavaKind();
+                            return JavaConstant.forIntegerKind(a.getJavaKind(), a.asLong() ^ b.asLong());
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp stamp1, Stamp stamp2) {
+                            IntegerStamp a = (IntegerStamp) stamp1;
+                            IntegerStamp b = (IntegerStamp) stamp2;
+                            assert a.getBits() == b.getBits();
+
+                            long variableBits = (a.downMask() ^ a.upMask()) | (b.downMask() ^ b.upMask());
+                            long newDownMask = (a.downMask() ^ b.downMask()) & ~variableBits;
+                            long newUpMask = (a.downMask() ^ b.downMask()) | variableBits;
+                            return stampForMask(a.getBits(), newDownMask, newUpMask);
+                        }
+
+                        @Override
+                        public boolean isNeutral(Constant value) {
+                            PrimitiveConstant n = (PrimitiveConstant) value;
+                            return n.asLong() == 0;
+                        }
+
+                        @Override
+                        public Constant getZero(Stamp s) {
+                            IntegerStamp stamp = (IntegerStamp) s;
+                            return JavaConstant.forPrimitiveInt(stamp.getBits(), 0);
+                        }
+                    },
+
+                    new ShiftOp.Shl() {
+
+                        @Override
+                        public Constant foldConstant(Constant value, int amount) {
+                            PrimitiveConstant c = (PrimitiveConstant) value;
+                            switch (c.getJavaKind()) {
+                                case Int:
+                                    return JavaConstant.forInt(c.asInt() << amount);
+                                case Long:
+                                    return JavaConstant.forLong(c.asLong() << amount);
+                                default:
+                                    throw GraalError.shouldNotReachHere();
+                            }
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp stamp, IntegerStamp shift) {
+                            IntegerStamp value = (IntegerStamp) stamp;
+                            int bits = value.getBits();
+                            if (value.isEmpty()) {
+                                return value;
+                            } else if (shift.isEmpty()) {
+                                return StampFactory.forInteger(bits).empty();
+                            } else if (value.upMask() == 0) {
+                                return value;
+                            }
+
+                            int shiftMask = getShiftAmountMask(stamp);
+                            int shiftBits = Integer.bitCount(shiftMask);
+                            if (shift.lowerBound() == shift.upperBound()) {
+                                int shiftAmount = (int) (shift.lowerBound() & shiftMask);
+                                if (shiftAmount == 0) {
+                                    return value;
+                                }
+                                // the mask of bits that will be lost or shifted into the sign bit
+                                long removedBits = -1L << (bits - shiftAmount - 1);
+                                if ((value.lowerBound() & removedBits) == 0 && (value.upperBound() & removedBits) == 0) {
+                                    /*
+                                     * use a better stamp if neither lower nor upper bound can lose
+                                     * bits
+                                     */
+                                    return new IntegerStamp(bits, value.lowerBound() << shiftAmount, value.upperBound() << shiftAmount, value.downMask() << shiftAmount, value.upMask() << shiftAmount);
+                                }
+                            }
+                            if ((shift.lowerBound() >>> shiftBits) == (shift.upperBound() >>> shiftBits)) {
+                                long defaultMask = CodeUtil.mask(bits);
+                                long downMask = defaultMask;
+                                long upMask = 0;
+                                for (long i = shift.lowerBound(); i <= shift.upperBound(); i++) {
+                                    if (shift.contains(i)) {
+                                        downMask &= value.downMask() << (i & shiftMask);
+                                        upMask |= value.upMask() << (i & shiftMask);
+                                    }
+                                }
+                                Stamp result = IntegerStamp.stampForMask(bits, downMask, upMask & defaultMask);
+                                return result;
+                            }
+                            return value.unrestricted();
+                        }
+
+                        @Override
+                        public int getShiftAmountMask(Stamp s) {
+                            IntegerStamp stamp = (IntegerStamp) s;
+                            assert CodeUtil.isPowerOf2(stamp.getBits());
+                            return stamp.getBits() - 1;
+                        }
+                    },
+
+                    new ShiftOp.Shr() {
+
+                        @Override
+                        public Constant foldConstant(Constant value, int amount) {
+                            PrimitiveConstant c = (PrimitiveConstant) value;
+                            switch (c.getJavaKind()) {
+                                case Int:
+                                    return JavaConstant.forInt(c.asInt() >> amount);
+                                case Long:
+                                    return JavaConstant.forLong(c.asLong() >> amount);
+                                default:
+                                    throw GraalError.shouldNotReachHere();
+                            }
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp stamp, IntegerStamp shift) {
+                            IntegerStamp value = (IntegerStamp) stamp;
+                            int bits = value.getBits();
+                            if (value.isEmpty()) {
+                                return value;
+                            } else if (shift.isEmpty()) {
+                                return StampFactory.forInteger(bits).empty();
+                            } else if (shift.lowerBound() == shift.upperBound()) {
+                                long shiftCount = shift.lowerBound() & getShiftAmountMask(stamp);
+                                if (shiftCount == 0) {
+                                    return stamp;
+                                }
+
+                                int extraBits = 64 - bits;
+                                long defaultMask = CodeUtil.mask(bits);
+                                // shifting back and forth performs sign extension
+                                long downMask = (value.downMask() << extraBits) >> (shiftCount + extraBits) & defaultMask;
+                                long upMask = (value.upMask() << extraBits) >> (shiftCount + extraBits) & defaultMask;
+                                return new IntegerStamp(bits, value.lowerBound() >> shiftCount, value.upperBound() >> shiftCount, downMask, upMask);
+                            }
+                            long mask = IntegerStamp.upMaskFor(bits, value.lowerBound(), value.upperBound());
+                            return IntegerStamp.stampForMask(bits, 0, mask);
+                        }
+
+                        @Override
+                        public int getShiftAmountMask(Stamp s) {
+                            IntegerStamp stamp = (IntegerStamp) s;
+                            assert CodeUtil.isPowerOf2(stamp.getBits());
+                            return stamp.getBits() - 1;
+                        }
+                    },
+
+                    new ShiftOp.UShr() {
+
+                        @Override
+                        public Constant foldConstant(Constant value, int amount) {
+                            PrimitiveConstant c = (PrimitiveConstant) value;
+                            switch (c.getJavaKind()) {
+                                case Int:
+                                    return JavaConstant.forInt(c.asInt() >>> amount);
+                                case Long:
+                                    return JavaConstant.forLong(c.asLong() >>> amount);
+                                default:
+                                    throw GraalError.shouldNotReachHere();
+                            }
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp stamp, IntegerStamp shift) {
+                            IntegerStamp value = (IntegerStamp) stamp;
+                            int bits = value.getBits();
+                            if (value.isEmpty()) {
+                                return value;
+                            } else if (shift.isEmpty()) {
+                                return StampFactory.forInteger(bits).empty();
+                            }
+
+                            if (shift.lowerBound() == shift.upperBound()) {
+                                long shiftCount = shift.lowerBound() & getShiftAmountMask(stamp);
+                                if (shiftCount == 0) {
+                                    return stamp;
+                                }
+
+                                long downMask = value.downMask() >>> shiftCount;
+                                long upMask = value.upMask() >>> shiftCount;
+                                if (value.lowerBound() < 0) {
+                                    return new IntegerStamp(bits, downMask, upMask, downMask, upMask);
+                                } else {
+                                    return new IntegerStamp(bits, value.lowerBound() >>> shiftCount, value.upperBound() >>> shiftCount, downMask, upMask);
+                                }
+                            }
+                            long mask = IntegerStamp.upMaskFor(bits, value.lowerBound(), value.upperBound());
+                            return IntegerStamp.stampForMask(bits, 0, mask);
+                        }
+
+                        @Override
+                        public int getShiftAmountMask(Stamp s) {
+                            IntegerStamp stamp = (IntegerStamp) s;
+                            assert CodeUtil.isPowerOf2(stamp.getBits());
+                            return stamp.getBits() - 1;
+                        }
+                    },
+
+                    new UnaryOp.Abs() {
+
+                        @Override
+                        public Constant foldConstant(Constant value) {
+                            PrimitiveConstant c = (PrimitiveConstant) value;
+                            return JavaConstant.forIntegerKind(c.getJavaKind(), Math.abs(c.asLong()));
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp input) {
+                            IntegerStamp stamp = (IntegerStamp) input;
+                            int bits = stamp.getBits();
+                            if (stamp.lowerBound() == CodeUtil.minValue(bits)) {
+                                return input.unrestricted();
+                            } else {
+                                long limit = Math.max(-stamp.lowerBound(), stamp.upperBound());
+                                return StampFactory.forInteger(bits, 0, limit);
+                            }
+                        }
+                    },
+
+                    null,
+
+                    new IntegerConvertOp.ZeroExtend() {
+
+                        @Override
+                        public Constant foldConstant(int inputBits, int resultBits, Constant c) {
+                            PrimitiveConstant value = (PrimitiveConstant) c;
+                            return JavaConstant.forPrimitiveInt(resultBits, CodeUtil.zeroExtend(value.asLong(), inputBits));
+                        }
+
+                        @Override
+                        public Stamp foldStamp(int inputBits, int resultBits, Stamp input) {
+                            IntegerStamp stamp = (IntegerStamp) input;
+                            assert inputBits == stamp.getBits();
+                            assert inputBits <= resultBits;
+
+                            if (inputBits == resultBits) {
+                                return input;
+                            }
+
+                            if (input.isEmpty()) {
+                                return StampFactory.forInteger(resultBits).empty();
+                            }
+
+                            long downMask = CodeUtil.zeroExtend(stamp.downMask(), inputBits);
+                            long upMask = CodeUtil.zeroExtend(stamp.upMask(), inputBits);
+                            long lowerBound = stamp.unsignedLowerBound();
+                            long upperBound = stamp.unsignedUpperBound();
+                            return IntegerStamp.create(resultBits, lowerBound, upperBound, downMask, upMask);
+                        }
+
+                        @Override
+                        public Stamp invertStamp(int inputBits, int resultBits, Stamp outStamp) {
+                            IntegerStamp stamp = (IntegerStamp) outStamp;
+                            if (stamp.isEmpty()) {
+                                return StampFactory.forInteger(inputBits).empty();
+                            }
+                            return StampFactory.forUnsignedInteger(inputBits, stamp.lowerBound(), stamp.upperBound(), stamp.downMask(), stamp.upMask());
+                        }
+                    },
+
+                    new IntegerConvertOp.SignExtend() {
+
+                        @Override
+                        public Constant foldConstant(int inputBits, int resultBits, Constant c) {
+                            PrimitiveConstant value = (PrimitiveConstant) c;
+                            return JavaConstant.forPrimitiveInt(resultBits, CodeUtil.signExtend(value.asLong(), inputBits));
+                        }
+
+                        @Override
+                        public Stamp foldStamp(int inputBits, int resultBits, Stamp input) {
+                            IntegerStamp stamp = (IntegerStamp) input;
+                            assert inputBits == stamp.getBits();
+                            assert inputBits <= resultBits;
+
+                            long defaultMask = CodeUtil.mask(resultBits);
+                            long downMask = CodeUtil.signExtend(stamp.downMask(), inputBits) & defaultMask;
+                            long upMask = CodeUtil.signExtend(stamp.upMask(), inputBits) & defaultMask;
+
+                            return new IntegerStamp(resultBits, stamp.lowerBound(), stamp.upperBound(), downMask, upMask);
+                        }
+
+                        @Override
+                        public Stamp invertStamp(int inputBits, int resultBits, Stamp outStamp) {
+                            IntegerStamp stamp = (IntegerStamp) outStamp;
+                            long mask = CodeUtil.mask(inputBits);
+                            return StampFactory.forIntegerWithMask(inputBits, stamp.lowerBound(), stamp.upperBound(), stamp.downMask() & mask, stamp.upMask() & mask);
+                        }
+                    },
+
+                    new IntegerConvertOp.Narrow() {
+
+                        @Override
+                        public Constant foldConstant(int inputBits, int resultBits, Constant c) {
+                            PrimitiveConstant value = (PrimitiveConstant) c;
+                            return JavaConstant.forPrimitiveInt(resultBits, CodeUtil.narrow(value.asLong(), resultBits));
+                        }
+
+                        @Override
+                        public Stamp foldStamp(int inputBits, int resultBits, Stamp input) {
+                            IntegerStamp stamp = (IntegerStamp) input;
+                            assert inputBits == stamp.getBits();
+                            assert resultBits <= inputBits;
+                            if (resultBits == inputBits) {
+                                return stamp;
+                            }
+
+                            final long upperBound;
+                            if (stamp.lowerBound() < CodeUtil.minValue(resultBits)) {
+                                upperBound = CodeUtil.maxValue(resultBits);
+                            } else {
+                                upperBound = saturate(stamp.upperBound(), resultBits);
+                            }
+                            final long lowerBound;
+                            if (stamp.upperBound() > CodeUtil.maxValue(resultBits)) {
+                                lowerBound = CodeUtil.minValue(resultBits);
+                            } else {
+                                lowerBound = saturate(stamp.lowerBound(), resultBits);
+                            }
+
+                            long defaultMask = CodeUtil.mask(resultBits);
+                            long newDownMask = stamp.downMask() & defaultMask;
+                            long newUpMask = stamp.upMask() & defaultMask;
+                            long newLowerBound = CodeUtil.signExtend((lowerBound | newDownMask) & newUpMask, resultBits);
+                            long newUpperBound = CodeUtil.signExtend((upperBound | newDownMask) & newUpMask, resultBits);
+                            return new IntegerStamp(resultBits, newLowerBound, newUpperBound, newDownMask, newUpMask);
+                        }
+                    },
+
+                    new FloatConvertOp(I2F) {
+
+                        @Override
+                        public Constant foldConstant(Constant c) {
+                            PrimitiveConstant value = (PrimitiveConstant) c;
+                            return JavaConstant.forFloat(value.asInt());
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp input) {
+                            IntegerStamp stamp = (IntegerStamp) input;
+                            assert stamp.getBits() == 32;
+                            float lowerBound = stamp.lowerBound();
+                            float upperBound = stamp.upperBound();
+                            return StampFactory.forFloat(JavaKind.Float, lowerBound, upperBound, true);
+                        }
+                    },
+
+                    new FloatConvertOp(L2F) {
+
+                        @Override
+                        public Constant foldConstant(Constant c) {
+                            PrimitiveConstant value = (PrimitiveConstant) c;
+                            return JavaConstant.forFloat(value.asLong());
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp input) {
+                            IntegerStamp stamp = (IntegerStamp) input;
+                            assert stamp.getBits() == 64;
+                            float lowerBound = stamp.lowerBound();
+                            float upperBound = stamp.upperBound();
+                            return StampFactory.forFloat(JavaKind.Float, lowerBound, upperBound, true);
+                        }
+                    },
+
+                    new FloatConvertOp(I2D) {
+
+                        @Override
+                        public Constant foldConstant(Constant c) {
+                            PrimitiveConstant value = (PrimitiveConstant) c;
+                            return JavaConstant.forDouble(value.asInt());
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp input) {
+                            IntegerStamp stamp = (IntegerStamp) input;
+                            assert stamp.getBits() == 32;
+                            double lowerBound = stamp.lowerBound();
+                            double upperBound = stamp.upperBound();
+                            return StampFactory.forFloat(JavaKind.Double, lowerBound, upperBound, true);
+                        }
+                    },
+
+                    new FloatConvertOp(L2D) {
+
+                        @Override
+                        public Constant foldConstant(Constant c) {
+                            PrimitiveConstant value = (PrimitiveConstant) c;
+                            return JavaConstant.forDouble(value.asLong());
+                        }
+
+                        @Override
+                        public Stamp foldStamp(Stamp input) {
+                            IntegerStamp stamp = (IntegerStamp) input;
+                            assert stamp.getBits() == 64;
+                            double lowerBound = stamp.lowerBound();
+                            double upperBound = stamp.upperBound();
+                            return StampFactory.forFloat(JavaKind.Double, lowerBound, upperBound, true);
+                        }
+                    });
+}