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Native function interface for the Truffle framework.
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/*
* Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* The Universal Permissive License (UPL), Version 1.0
*
* Subject to the condition set forth below, permission is hereby granted to any
* person obtaining a copy of this software, associated documentation and/or
* data (collectively the "Software"), free of charge and under any and all
* copyright rights in the Software, and any and all patent rights owned or
* freely licensable by each licensor hereunder covering either (i) the
* unmodified Software as contributed to or provided by such licensor, or (ii)
* the Larger Works (as defined below), to deal in both
*
* (a) the Software, and
*
* (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
* one is included with the Software each a "Larger Work" to which the Software
* is contributed by such licensors),
*
* without restriction, including without limitation the rights to copy, create
* derivative works of, display, perform, and distribute the Software and make,
* use, sell, offer for sale, import, export, have made, and have sold the
* Software and the Larger Work(s), and to sublicense the foregoing rights on
* either these or other terms.
*
* This license is subject to the following condition:
*
* The above copyright notice and either this complete permission notice or at a
* minimum a reference to the UPL must be included in all copies or substantial
* portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
package com.oracle.truffle.nfi;
import java.math.BigInteger;
import java.nio.ByteOrder;
import com.oracle.truffle.api.CompilerDirectives;
import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
import com.oracle.truffle.api.dsl.Specialization;
import com.oracle.truffle.api.interop.InteropLibrary;
import com.oracle.truffle.api.interop.InvalidBufferOffsetException;
import com.oracle.truffle.api.interop.TruffleObject;
import com.oracle.truffle.api.interop.UnsupportedMessageException;
import com.oracle.truffle.api.library.CachedLibrary;
import com.oracle.truffle.api.library.ExportLibrary;
import com.oracle.truffle.api.library.ExportMessage;
import com.oracle.truffle.nfi.api.SerializableLibrary;
final class LongDoubleUtil {
static Object interopToFP80(Object number) {
assert InteropLibrary.getUncached().isNumber(number);
return new FP80Number(number);
}
static Object fp80ToNumber(Object buffer) {
assert InteropLibrary.getUncached().hasBufferElements(buffer);
return new FP80Buffer(buffer);
}
static Object interopToFP128(Object number) {
assert InteropLibrary.getUncached().isNumber(number);
return new FP128Number(number);
}
static Object fp128ToNumber(Object buffer) {
assert InteropLibrary.getUncached().hasBufferElements(buffer);
return new FP128Buffer(buffer);
}
private static final class DoubleHelper {
private static final int FRACTION_BITS = 52;
private static final int EXPONENT_BITS = 11;
private static final long EXPONENT_MASK = ((1L << EXPONENT_BITS) - 1) << FRACTION_BITS;
private static final long FRACTION_MASK = (1L << FRACTION_BITS) - 1;
private static final int EXPONENT_BIAS = 1023;
}
@ExportLibrary(value = SerializableLibrary.class, useForAOT = false)
static final class FP80Number implements TruffleObject {
private static final int FRACTION_BITS = 64;
private static final int SIGN_MASK = 1 << 15;
private static final int EXPONENT_MASK = SIGN_MASK - 1;
private static final int EXPONENT_BIAS = 16383;
private static final long INF_FRACTION = 0x8000_0000_0000_0000L;
private static final long NAN_FRACTION = 0xc000_0000_0000_0000L;
final Object number;
private FP80Number(Object number) {
this.number = number;
}
@ExportMessage
@SuppressWarnings("static-method")
boolean isSerializable() {
return true;
}
@ExportMessage
static class Serialize {
@Specialization(limit = "1", guards = "numberInterop.fitsInLong(self.number)")
static void doLong(FP80Number self, Object buffer,
@CachedLibrary("self.number") InteropLibrary numberInterop,
@CachedLibrary("buffer") InteropLibrary bufferInterop) {
try {
long number = numberInterop.asLong(self.number);
if (number == 0) {
bufferInterop.writeBufferLong(buffer, ByteOrder.nativeOrder(), 0, 0);
bufferInterop.writeBufferShort(buffer, ByteOrder.nativeOrder(), 8, (short) 0);
return;
}
int sign = number < 0 ? SIGN_MASK : 0;
long val = Math.abs(number);
int leadingOnePosition = Long.SIZE - Long.numberOfLeadingZeros(val);
int exponent = FP80Number.EXPONENT_BIAS + (leadingOnePosition - 1);
assert (exponent & FP80Number.EXPONENT_MASK) == exponent : "exponent out of range";
long fractionMask;
if (leadingOnePosition == Long.SIZE || leadingOnePosition == Long.SIZE - 1) {
fractionMask = 0xffffffff;
} else {
fractionMask = (1L << leadingOnePosition + 1) - 1;
}
long maskedFractionValue = val & fractionMask;
long fraction = maskedFractionValue << (Long.SIZE - leadingOnePosition);
bufferInterop.writeBufferLong(buffer, ByteOrder.nativeOrder(), 0, fraction);
bufferInterop.writeBufferShort(buffer, ByteOrder.nativeOrder(), 8, (short) (sign | exponent));
} catch (UnsupportedMessageException | InvalidBufferOffsetException ex) {
throw CompilerDirectives.shouldNotReachHere(ex);
}
}
@Specialization(limit = "1", guards = "numberInterop.fitsInDouble(self.number)")
static void doDouble(FP80Number self, Object buffer,
@CachedLibrary("self.number") InteropLibrary numberInterop,
@CachedLibrary("buffer") InteropLibrary bufferInterop) {
try {
double number = numberInterop.asDouble(self.number);
long rawValue = Double.doubleToRawLongBits(number);
int sign = rawValue < 0 ? SIGN_MASK : 0;
long absRaw = Math.abs(rawValue);
if (absRaw == 0) {
// positive or negative zero
bufferInterop.writeBufferLong(buffer, ByteOrder.nativeOrder(), 0, 0);
bufferInterop.writeBufferShort(buffer, ByteOrder.nativeOrder(), 8, (short) sign);
return;
}
if ((absRaw & DoubleHelper.EXPONENT_MASK) == DoubleHelper.EXPONENT_MASK) {
if ((absRaw & DoubleHelper.FRACTION_MASK) == 0) {
// infinity
bufferInterop.writeBufferLong(buffer, ByteOrder.nativeOrder(), 0, FP80Number.INF_FRACTION);
} else {
// NaN
bufferInterop.writeBufferLong(buffer, ByteOrder.nativeOrder(), 0, FP80Number.NAN_FRACTION);
}
bufferInterop.writeBufferShort(buffer, ByteOrder.nativeOrder(), 8, (short) (sign | FP80Number.EXPONENT_MASK));
}
long doubleExponent = (absRaw & DoubleHelper.EXPONENT_MASK) >> DoubleHelper.FRACTION_BITS;
int fp80Exponent = (int) doubleExponent - DoubleHelper.EXPONENT_BIAS + FP80Number.EXPONENT_BIAS;
long doubleFraction = rawValue & DoubleHelper.FRACTION_MASK;
long shiftedDoubleFraction = doubleFraction << (63 - DoubleHelper.FRACTION_BITS);
long leadingOne = 1L << 63;
long fp80Fraction = leadingOne | shiftedDoubleFraction;
bufferInterop.writeBufferLong(buffer, ByteOrder.nativeOrder(), 0, fp80Fraction);
bufferInterop.writeBufferShort(buffer, ByteOrder.nativeOrder(), 8, (short) (sign | fp80Exponent));
} catch (UnsupportedMessageException | InvalidBufferOffsetException ex) {
throw CompilerDirectives.shouldNotReachHere(ex);
}
}
}
}
@ExportLibrary(value = SerializableLibrary.class, useForAOT = false)
static final class FP128Number implements TruffleObject {
static final long DOUBLE_FRACTION_BIT_WIDTH = 52;
private static final long SIGN_MASK = 1L << 63;
private static final int EXPONENT_BIAS = 16383;
private static final int FRACTION_BIT_WIDTH = 112;
public static final int EXPONENT_POSITION = FRACTION_BIT_WIDTH - Long.SIZE; // 112 - 64 = 48
public static final long EXPONENT_MASK = 0b111111111111111L << EXPONENT_POSITION;
public static final long FRACTION_MASK = (1L << EXPONENT_POSITION) - 1;
public static final int DOUBLE_SIGN_POS = 63;
final Object number;
private FP128Number(Object number) {
this.number = number;
}
@ExportMessage
@SuppressWarnings("static-method")
boolean isSerializable() {
return true;
}
@ExportMessage
static class Serialize {
@Specialization(limit = "1", guards = "numberInterop.fitsInLong(self.number)")
static void doLong(FP128Number self, Object buffer,
@CachedLibrary("self.number") InteropLibrary numberInterop,
@CachedLibrary("buffer") InteropLibrary bufferInterop) {
try {
long number = numberInterop.asLong(self.number);
if (number == 0) {
bufferInterop.writeBufferLong(buffer, ByteOrder.nativeOrder(), 0, 0);
bufferInterop.writeBufferLong(buffer, ByteOrder.nativeOrder(), 8, 0);
return;
}
long sign = number < 0 ? SIGN_MASK : 0;
long val = Math.abs(number);
int leadingOnePosition = Long.SIZE - Long.numberOfLeadingZeros(val);
long exponent = EXPONENT_BIAS + (leadingOnePosition - 1);
long shiftAmount = FRACTION_BIT_WIDTH - leadingOnePosition + 1;
long fraction;
long exponentFraction;
if (shiftAmount >= Long.SIZE) { // TODO: Need to test both cases.
exponentFraction = (exponent << EXPONENT_POSITION) | ((val << (shiftAmount - Long.SIZE)) & FRACTION_MASK);
fraction = 0;
} else {
exponentFraction = (exponent << EXPONENT_POSITION) | ((val >> (Long.SIZE - shiftAmount)) & FRACTION_MASK);
fraction = val << (shiftAmount);
}
bufferInterop.writeBufferLong(buffer, ByteOrder.nativeOrder(), 0, fraction);
bufferInterop.writeBufferLong(buffer, ByteOrder.nativeOrder(), 8, (sign | exponentFraction));
} catch (UnsupportedMessageException | InvalidBufferOffsetException ex) {
throw CompilerDirectives.shouldNotReachHere(ex);
}
}
@Specialization(limit = "1", guards = "numberInterop.fitsInDouble(self.number)")
static void doDouble(FP128Number self, Object buffer,
@CachedLibrary("self.number") InteropLibrary numberInterop,
@CachedLibrary("buffer") InteropLibrary bufferInterop) {
try {
double number = numberInterop.asDouble(self.number);
long rawValue = Double.doubleToRawLongBits(number);
long sign = rawValue < 0 ? SIGN_MASK : 0;
long absRaw = Math.abs(rawValue);
if (absRaw == 0) {
// positive or negative zero
bufferInterop.writeBufferLong(buffer, ByteOrder.nativeOrder(), 0, 0);
bufferInterop.writeBufferLong(buffer, ByteOrder.nativeOrder(), 8, sign);
return;
}
int doubleExponent = Math.getExponent(number);
int biasedExponent = doubleExponent + EXPONENT_BIAS;
long doubleFraction = rawValue & DoubleHelper.FRACTION_MASK;
// 112 - 52 = 60
long shiftAmount = FRACTION_BIT_WIDTH - DOUBLE_FRACTION_BIT_WIDTH;
long fraction = doubleFraction << (shiftAmount);
// 64 - 60 = 4
long biasedExponentFraction = ((long) biasedExponent << EXPONENT_POSITION) | (doubleFraction >> (Long.SIZE - shiftAmount));
bufferInterop.writeBufferLong(buffer, ByteOrder.nativeOrder(), 0, fraction);
bufferInterop.writeBufferLong(buffer, ByteOrder.nativeOrder(), 8, (sign | biasedExponentFraction));
} catch (UnsupportedMessageException | InvalidBufferOffsetException ex) {
throw CompilerDirectives.shouldNotReachHere(ex);
}
}
}
}
@ExportLibrary(value = InteropLibrary.class, delegateTo = "buffer")
static final class FP80Buffer implements TruffleObject {
final Object buffer;
FP80Buffer(Object buffer) {
this.buffer = buffer;
}
@ExportMessage
boolean isNumber(@CachedLibrary("this.buffer") InteropLibrary interop) {
return interop.hasBufferElements(buffer);
}
@ExportMessage
boolean fitsInByte(@CachedLibrary("this.buffer") InteropLibrary interop) {
try {
long value = asLong(interop);
return value == (byte) value;
} catch (UnsupportedMessageException ex) {
return false;
}
}
@ExportMessage
boolean fitsInShort(@CachedLibrary("this.buffer") InteropLibrary interop) {
try {
long value = asLong(interop);
return value == (short) value;
} catch (UnsupportedMessageException ex) {
return false;
}
}
@ExportMessage
boolean fitsInInt(@CachedLibrary("this.buffer") InteropLibrary interop) {
try {
long value = asLong(interop);
return value == (int) value;
} catch (UnsupportedMessageException ex) {
return false;
}
}
@ExportMessage
boolean fitsInLong(@CachedLibrary("this.buffer") InteropLibrary interop) {
try {
asLong(interop);
return true;
} catch (UnsupportedMessageException ex) {
return false;
}
}
@ExportMessage
boolean fitsInBigInteger(@CachedLibrary("this.buffer") InteropLibrary interop) {
try {
asBigInteger(interop);
return true;
} catch (UnsupportedMessageException ex) {
return false;
}
}
@ExportMessage
boolean fitsInFloat(@CachedLibrary("this.buffer") InteropLibrary interop) {
if (fitsInDouble()) {
try {
double value = asDouble(interop);
return value == (float) value;
} catch (UnsupportedMessageException ex) {
return false;
}
} else {
return false;
}
}
@ExportMessage
@SuppressWarnings("static-method")
boolean fitsInDouble() {
/*
* Technically this is not correct, but there is no higher precision type available in
* interop, so if we would return false here, there would be no way to get any number
* out.
*/
return true;
}
@ExportMessage
byte asByte(@CachedLibrary("this.buffer") InteropLibrary interop) throws UnsupportedMessageException {
long value = asLong(interop);
if (value != (byte) value) {
throw UnsupportedMessageException.create();
}
return (byte) value;
}
@ExportMessage
short asShort(@CachedLibrary("this.buffer") InteropLibrary interop) throws UnsupportedMessageException {
long value = asLong(interop);
if (value != (short) value) {
throw UnsupportedMessageException.create();
}
return (short) value;
}
@ExportMessage
int asInt(@CachedLibrary("this.buffer") InteropLibrary interop) throws UnsupportedMessageException {
long value = asLong(interop);
if (value != (int) value) {
throw UnsupportedMessageException.create();
}
return (int) value;
}
@ExportMessage
long asLong(@CachedLibrary("this.buffer") InteropLibrary interop) throws UnsupportedMessageException {
try {
short exponent = interop.readBufferShort(buffer, ByteOrder.LITTLE_ENDIAN, 8);
if ((exponent & FP80Number.EXPONENT_MASK) == FP80Number.EXPONENT_MASK) {
// NaN or infinity
throw UnsupportedMessageException.create();
}
int unbiasedExponent = (exponent & FP80Number.EXPONENT_MASK) - FP80Number.EXPONENT_BIAS;
long fraction = interop.readBufferLong(buffer, ByteOrder.LITTLE_ENDIAN, 0);
int shift = FP80Number.FRACTION_BITS - unbiasedExponent - 1;
long ret = fraction >>> shift;
if (ret < 0 || fraction != (ret << shift)) {
// overflow or not a whole number
throw UnsupportedMessageException.create();
}
if ((exponent & FP80Number.SIGN_MASK) == 0) {
return ret;
} else {
return -ret;
}
} catch (InvalidBufferOffsetException ex) {
throw UnsupportedMessageException.create();
}
}
@ExportMessage
BigInteger asBigInteger(@CachedLibrary("this.buffer") InteropLibrary interop) throws UnsupportedMessageException {
int unbiasedExponent;
short exponent;
long fractionLong;
try {
exponent = interop.readBufferShort(buffer, ByteOrder.LITTLE_ENDIAN, 8);
if ((exponent & FP80Number.EXPONENT_MASK) == FP80Number.EXPONENT_MASK) {
// NaN or infinity
throw UnsupportedMessageException.create();
}
unbiasedExponent = (exponent & FP80Number.EXPONENT_MASK) - FP80Number.EXPONENT_BIAS;
fractionLong = interop.readBufferLong(buffer, ByteOrder.LITTLE_ENDIAN, 0);
} catch (InvalidBufferOffsetException ex) {
throw UnsupportedMessageException.create();
}
return toBigInteger(fractionLong, exponent, unbiasedExponent);
}
@TruffleBoundary
private static BigInteger toBigInteger(long fractionLong, short exponent, int unbiasedExponent) throws UnsupportedMessageException {
BigInteger fraction = toUnsignedBigInteger(fractionLong);
int shift = FP80Number.FRACTION_BITS - unbiasedExponent - 1;
BigInteger ret;
if (shift >= 0) {
ret = fraction.shiftRight(shift);
BigInteger fractionBack = ret.shiftLeft(shift);
if (!fraction.equals(fractionBack)) {
// not a whole number
throw UnsupportedMessageException.create();
}
} else {
ret = fraction.shiftLeft(-shift);
}
if ((exponent & FP80Number.SIGN_MASK) == 0) {
return ret;
} else {
return ret.negate();
}
}
private static BigInteger toUnsignedBigInteger(long i) {
if (i >= 0L) {
return BigInteger.valueOf(i);
} else {
int upper = (int) (i >>> 32);
int lower = (int) i;
// return (upper << 32) + lower
return (BigInteger.valueOf(Integer.toUnsignedLong(upper))).shiftLeft(32).add(BigInteger.valueOf(Integer.toUnsignedLong(lower)));
}
}
@ExportMessage
float asFloat(@CachedLibrary("this.buffer") InteropLibrary interop) throws UnsupportedMessageException {
return (float) asDouble(interop);
}
@ExportMessage
double asDouble(@CachedLibrary("this.buffer") InteropLibrary interop) throws UnsupportedMessageException {
try {
long fraction = interop.readBufferLong(buffer, ByteOrder.LITTLE_ENDIAN, 0);
short exponent = interop.readBufferShort(buffer, ByteOrder.LITTLE_ENDIAN, 8);
if (fraction == 0) {
if (exponent == 0) {
return 0.0;
} else if (exponent == (short) FP80Number.SIGN_MASK) {
return -0.0;
}
}
if ((exponent & FP80Number.EXPONENT_MASK) == FP80Number.EXPONENT_MASK) {
if (fraction == 1L << 63) {
// infinity
if ((exponent & FP80Number.SIGN_MASK) == 0) {
return Double.POSITIVE_INFINITY;
} else {
return Double.NEGATIVE_INFINITY;
}
} else {
// NaN
return Double.NaN;
}
}
int unbiasedExponent = (exponent & FP80Number.EXPONENT_MASK) - FP80Number.EXPONENT_BIAS;
int doubleExponent = unbiasedExponent + DoubleHelper.EXPONENT_BIAS;
long doubleFraction = (fraction << 1) >>> (FP80Number.FRACTION_BITS - DoubleHelper.FRACTION_BITS);
long shiftedExponent = (long) doubleExponent << DoubleHelper.FRACTION_BITS;
long signBit = (long) (exponent & FP80Number.SIGN_MASK) << (Long.SIZE - Short.SIZE);
return Double.longBitsToDouble(signBit | shiftedExponent | doubleFraction);
} catch (InvalidBufferOffsetException ex) {
throw UnsupportedMessageException.create();
}
}
@TruffleBoundary
private static String format(long fraction, short exponent) {
return String.format("0xK%04x%016x", exponent, fraction);
}
@ExportMessage
String toDisplayString(@SuppressWarnings("unused") boolean allowSideEffects,
@CachedLibrary("this.buffer") InteropLibrary interop) {
try {
long fraction = interop.readBufferLong(buffer, ByteOrder.LITTLE_ENDIAN, 0);
short exponent = interop.readBufferShort(buffer, ByteOrder.LITTLE_ENDIAN, 8);
return format(fraction, exponent);
} catch (UnsupportedMessageException | InvalidBufferOffsetException ex) {
return "";
}
}
}
@ExportLibrary(value = InteropLibrary.class, delegateTo = "buffer")
static final class FP128Buffer implements TruffleObject {
final Object buffer;
FP128Buffer(Object buffer) {
this.buffer = buffer;
}
@ExportMessage
boolean isNumber(@CachedLibrary("this.buffer") InteropLibrary interop) {
return interop.hasBufferElements(buffer);
}
@ExportMessage
boolean fitsInByte(@CachedLibrary("this.buffer") InteropLibrary interop) {
try {
long value = asLong(interop);
return value == (byte) value;
} catch (UnsupportedMessageException ex) {
return false;
}
}
@ExportMessage
boolean fitsInShort(@CachedLibrary("this.buffer") InteropLibrary interop) {
try {
long value = asLong(interop);
return value == (short) value;
} catch (UnsupportedMessageException ex) {
return false;
}
}
@ExportMessage
boolean fitsInInt(@CachedLibrary("this.buffer") InteropLibrary interop) {
try {
long value = asLong(interop);
return value == (int) value;
} catch (UnsupportedMessageException ex) {
return false;
}
}
@ExportMessage
boolean fitsInLong(@CachedLibrary("this.buffer") InteropLibrary interop) {
try {
asLong(interop);
return true;
} catch (UnsupportedMessageException ex) {
return false;
}
}
@ExportMessage
boolean fitsInBigInteger(@CachedLibrary("this.buffer") InteropLibrary interop) {
try {
asBigInteger(interop);
return true;
} catch (UnsupportedMessageException ex) {
return false;
}
}
@ExportMessage
boolean fitsInFloat(@CachedLibrary("this.buffer") InteropLibrary interop) {
if (fitsInDouble()) {
try {
double value = asDouble(interop);
return value == (float) value;
} catch (UnsupportedMessageException ex) {
return false;
}
} else {
return false;
}
}
@ExportMessage
@SuppressWarnings("static-method")
boolean fitsInDouble() {
/*
* Technically this is not correct, but there is no higher precision type available in
* interop, so if we would return false here, there would be no way to get any number
* out.
*/
return true;
}
@ExportMessage
byte asByte(@CachedLibrary("this.buffer") InteropLibrary interop) throws UnsupportedMessageException {
long value = asLong(interop);
if (value != (byte) value) {
throw UnsupportedMessageException.create();
}
return (byte) value;
}
@ExportMessage
short asShort(@CachedLibrary("this.buffer") InteropLibrary interop) throws UnsupportedMessageException {
long value = asLong(interop);
if (value != (short) value) {
throw UnsupportedMessageException.create();
}
return (short) value;
}
@ExportMessage
int asInt(@CachedLibrary("this.buffer") InteropLibrary interop) throws UnsupportedMessageException {
long value = asLong(interop);
if (value != (int) value) {
throw UnsupportedMessageException.create();
}
return (int) value;
}
@ExportMessage
long asLong(@CachedLibrary("this.buffer") InteropLibrary interop) throws UnsupportedMessageException {
try {
long fraction = interop.readBufferLong(buffer, ByteOrder.LITTLE_ENDIAN, 0);
long expSignFraction = interop.readBufferLong(buffer, ByteOrder.LITTLE_ENDIAN, 8);
if ((expSignFraction & FP128Number.EXPONENT_MASK) == FP128Number.EXPONENT_MASK) {
// NaN or infinity
throw UnsupportedMessageException.create();
}
long unbiasedExponent = getUnbiasedExponent(expSignFraction);
long returnFraction = (1L << unbiasedExponent);
if (unbiasedExponent < 0) {
return 0;
} else if (unbiasedExponent <= 48) {
returnFraction |= (expSignFraction & FP128Number.FRACTION_MASK) >>> ((FP128Number.EXPONENT_POSITION) - unbiasedExponent);
} else if (unbiasedExponent < 64) {
returnFraction |= (expSignFraction & FP128Number.FRACTION_MASK) << (unbiasedExponent - FP128Number.EXPONENT_POSITION);
returnFraction |= fraction >>> (Long.SIZE - (unbiasedExponent - FP128Number.EXPONENT_POSITION));
} else {
returnFraction = 0L;
}
if ((expSignFraction & FP128Number.SIGN_MASK) == 0) {
return returnFraction;
} else {
return -returnFraction;
}
} catch (InvalidBufferOffsetException ex) {
throw UnsupportedMessageException.create();
}
}
@ExportMessage
BigInteger asBigInteger(@CachedLibrary("this.buffer") InteropLibrary interop) throws UnsupportedMessageException {
long expSignFraction;
long fractionLong;
try {
expSignFraction = interop.readBufferLong(buffer, ByteOrder.LITTLE_ENDIAN, 8);
if ((expSignFraction & FP128Number.EXPONENT_MASK) == FP128Number.EXPONENT_MASK) {
// NaN or infinity
throw UnsupportedMessageException.create();
}
fractionLong = interop.readBufferLong(buffer, ByteOrder.LITTLE_ENDIAN, 0);
} catch (InvalidBufferOffsetException ex) {
throw UnsupportedMessageException.create();
}
return toBigInteger(fractionLong, expSignFraction);
}
@TruffleBoundary
private static BigInteger toBigInteger(long longFraction, long expSignFraction) throws UnsupportedMessageException {
if (longFraction == 0 && (expSignFraction & (~FP128Number.SIGN_MASK)) == 0) {
return BigInteger.ZERO;
}
long unbiasedExponent = getUnbiasedExponent(expSignFraction);
BigInteger bigIntegerFraction = fractionToUnsignedBigInteger(longFraction, expSignFraction);
int shift = (int) (FP128Number.FRACTION_BIT_WIDTH - unbiasedExponent);
BigInteger ret;
if (shift > 0) {
ret = bigIntegerFraction.shiftRight(shift);
BigInteger fractionBack = ret.shiftLeft(shift);
if (!bigIntegerFraction.equals(fractionBack)) {
// not a whole number
throw UnsupportedMessageException.create();
}
} else {
ret = bigIntegerFraction.shiftLeft(-shift);
}
if ((expSignFraction & FP128Number.SIGN_MASK) == 0) {
return ret;
} else {
return ret.negate();
}
}
private static BigInteger fractionToUnsignedBigInteger(long fraction, long expSignFraction) {
long extractedFraction = (expSignFraction & FP128Number.FRACTION_MASK) + (1L << FP128Number.EXPONENT_POSITION);
long upperFraction = ((extractedFraction << 1) + (fraction >>> 63));
long lowerFraction = (fraction & Long.MAX_VALUE);
return (BigInteger.valueOf(upperFraction).shiftLeft(63).add(BigInteger.valueOf(lowerFraction)));
}
@ExportMessage
float asFloat(@CachedLibrary("this.buffer") InteropLibrary interop) throws UnsupportedMessageException {
return (float) asDouble(interop);
}
private static long getUnbiasedExponent(long expSignFraction) {
return ((expSignFraction & FP128Number.EXPONENT_MASK) >>> (FP128Number.EXPONENT_POSITION)) - (FP128Number.EXPONENT_BIAS);
}
@ExportMessage
double asDouble(@CachedLibrary("this.buffer") InteropLibrary interop) throws UnsupportedMessageException {
try {
long fraction = interop.readBufferLong(buffer, ByteOrder.LITTLE_ENDIAN, 0);
long expSignFraction = interop.readBufferLong(buffer, ByteOrder.LITTLE_ENDIAN, 8);
if (fraction == 0) {
if (expSignFraction == 0) {
return 0.0;
} else if (expSignFraction == FP128Number.SIGN_MASK) {
return -0.0;
}
}
long doubleExponent = getUnbiasedExponent(expSignFraction) + DoubleHelper.EXPONENT_BIAS;
/* 48bits from expSignFraction, with 4 bits shift left. */
long doubleFraction = (expSignFraction & FP128Number.FRACTION_MASK) << (FP128Number.DOUBLE_FRACTION_BIT_WIDTH - FP128Number.EXPONENT_POSITION);
// 4bits from fraction
doubleFraction |= fraction >>> (Long.SIZE - (FP128Number.DOUBLE_FRACTION_BIT_WIDTH - FP128Number.EXPONENT_POSITION));
long signBit = (getSign(expSignFraction) ? 1L : 0L) << FP128Number.DOUBLE_SIGN_POS;
// TODO: overflow case. Test this.
long shiftedExponent = doubleExponent << FP128Number.DOUBLE_FRACTION_BIT_WIDTH;
long rawVal = doubleFraction | shiftedExponent | signBit;
return Double.longBitsToDouble(rawVal);
} catch (InvalidBufferOffsetException ex) {
throw UnsupportedMessageException.create();
}
}
private static boolean getSign(long expSignFraction) {
return (expSignFraction & FP128Number.SIGN_MASK) != 0;
}
@TruffleBoundary
private static String format(long fraction, long exponent) {
return String.format("0xK%04x%028x", exponent, fraction);
}
@ExportMessage
String toDisplayString(@SuppressWarnings("unused") boolean allowSideEffects,
@CachedLibrary("this.buffer") InteropLibrary interop) {
try {
long fraction = interop.readBufferLong(buffer, ByteOrder.LITTLE_ENDIAN, 0);
long exponent = interop.readBufferLong(buffer, ByteOrder.LITTLE_ENDIAN, 8);
return format(fraction, exponent);
} catch (UnsupportedMessageException | InvalidBufferOffsetException ex) {
return "";
}
}
}
}