//
// The LLVM Compiler Infrastructure
//
-// This file was developed by Neil Booth and is distributed under the
-// University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
//
//===----------------------------------------------------------------------===//
+#include "llvm/ADT/APFloat.h"
+#include "llvm/ADT/FoldingSet.h"
#include <cassert>
#include <cstring>
-#include "llvm/ADT/APFloat.h"
#include "llvm/Support/MathExtras.h"
using namespace llvm;
If the exponent overflows, returns a large exponent with the
appropriate sign. */
- static int
+ int
readExponent(const char *p)
{
bool isNegative;
/* This is ugly and needs cleaning up, but I don't immediately see
how whilst remaining safe. */
- static int
+ int
totalExponent(const char *p, int exponentAdjustment)
{
integerPart unsignedExponent;
is taken to have the decimal point after a single leading
non-zero digit.
- If the value is zero, V->firstSigDigit points to a zero, and the
- return exponent is zero.
+ If the value is zero, V->firstSigDigit points to a non-digit, and
+ the return exponent is zero.
*/
struct decimalInfo {
const char *firstSigDigit;
/* Place pow(5, power) in DST, and return the number of parts used.
DST must be at least one part larger than size of the answer. */
- static unsigned int
+ unsigned int
powerOf5(integerPart *dst, unsigned int power)
{
static integerPart firstEightPowers[] = { 1, 5, 25, 125, 625, 3125,
/* Write out an integerPart in hexadecimal, starting with the most
significant nibble. Write out exactly COUNT hexdigits, return
COUNT. */
- static unsigned int
+ unsigned int
partAsHex (char *dst, integerPart part, unsigned int count,
const char *hexDigitChars)
{
}
/* Write out an unsigned decimal integer. */
- static char *
+ char *
writeUnsignedDecimal (char *dst, unsigned int n)
{
char buff[40], *p;
}
/* Write out a signed decimal integer. */
- static char *
+ char *
writeSignedDecimal (char *dst, int value)
{
if (value < 0) {
category != rhs.category ||
sign != rhs.sign)
return false;
- if (semantics==(const llvm::fltSemantics* const)&PPCDoubleDouble &&
+ if (semantics==(const llvm::fltSemantics*)&PPCDoubleDouble &&
sign2 != rhs.sign2)
return false;
if (category==fcZero || category==fcInfinity)
return true;
else if (category==fcNormal && exponent!=rhs.exponent)
return false;
- else if (semantics==(const llvm::fltSemantics* const)&PPCDoubleDouble &&
+ else if (semantics==(const llvm::fltSemantics*)&PPCDoubleDouble &&
exponent2!=rhs.exponent2)
return false;
else {
freeSignificand();
}
+// Profile - This method 'profiles' an APFloat for use with FoldingSet.
+void APFloat::Profile(FoldingSetNodeID& ID) const {
+ ID.Add(convertToAPInt());
+}
+
unsigned int
APFloat::partCount() const
{
case convolve(fcInfinity, fcInfinity):
/* Differently signed infinities can only be validly
subtracted. */
- if(sign ^ rhs.sign != subtract) {
+ if((sign ^ rhs.sign) != subtract) {
makeNaN();
return opInvalidOp;
}
/* Determine if the operation on the absolute values is effectively
an addition or subtraction. */
- subtract ^= (sign ^ rhs.sign);
+ subtract ^= (sign ^ rhs.sign) ? true : false;
/* Are we bigger exponent-wise than the RHS? */
bits = exponent - rhs.exponent;
fs = normalize(rounding_mode, lostFraction);
} else if (category == fcNaN) {
int shift = toSemantics.precision - semantics->precision;
+ // Do this now so significandParts gets the right answer
+ semantics = &toSemantics;
// No normalization here, just truncate
if (shift>0)
APInt::tcShiftLeft(significandParts(), newPartCount, shift);
// does not give you back the same bits. This is dubious, and we
// don't currently do it. You're really supposed to get
// an invalid operation signal at runtime, but nobody does that.
- semantics = &toSemantics;
fs = opOK;
} else {
semantics = &toSemantics;
/* Convert a floating point number to an integer according to the
rounding mode. If the rounded integer value is out of range this
- returns an invalid operation exception. If the rounded value is in
+ returns an invalid operation exception and the contents of the
+ destination parts are unspecified. If the rounded value is in
range but the floating point number is not the exact integer, the C
standard doesn't require an inexact exception to be raised. IEEE
854 does require it so we do that.
Note that for conversions to integer type the C standard requires
round-to-zero to always be used. */
APFloat::opStatus
-APFloat::convertToInteger(integerPart *parts, unsigned int width,
- bool isSigned,
- roundingMode rounding_mode) const
+APFloat::convertToSignExtendedInteger(integerPart *parts, unsigned int width,
+ bool isSigned,
+ roundingMode rounding_mode) const
{
lostFraction lost_fraction;
- unsigned int msb, partsCount;
- int bits;
+ const integerPart *src;
+ unsigned int dstPartsCount, truncatedBits;
assertArithmeticOK(*semantics);
- partsCount = partCountForBits(width);
- /* Handle the three special cases first. We produce
- a deterministic result even for the Invalid cases. */
- if (category == fcNaN) {
- // Neither sign nor isSigned affects this.
- APInt::tcSet(parts, 0, partsCount);
- return opInvalidOp;
- }
- if (category == fcInfinity) {
- if (!sign && isSigned)
- APInt::tcSetLeastSignificantBits(parts, partsCount, width-1);
- else if (!sign && !isSigned)
- APInt::tcSetLeastSignificantBits(parts, partsCount, width);
- else if (sign && isSigned) {
- APInt::tcSetLeastSignificantBits(parts, partsCount, 1);
- APInt::tcShiftLeft(parts, partsCount, width-1);
- } else // sign && !isSigned
- APInt::tcSet(parts, 0, partsCount);
+ /* Handle the three special cases first. */
+ if(category == fcInfinity || category == fcNaN)
return opInvalidOp;
- }
- if (category == fcZero) {
- APInt::tcSet(parts, 0, partsCount);
+
+ dstPartsCount = partCountForBits(width);
+
+ if(category == fcZero) {
+ APInt::tcSet(parts, 0, dstPartsCount);
return opOK;
}
- /* Shift the bit pattern so the fraction is lost. */
- APFloat tmp(*this);
+ src = significandParts();
- bits = (int) semantics->precision - 1 - exponent;
-
- if(bits > 0) {
- lost_fraction = tmp.shiftSignificandRight(bits);
+ /* Step 1: place our absolute value, with any fraction truncated, in
+ the destination. */
+ if (exponent < 0) {
+ /* Our absolute value is less than one; truncate everything. */
+ APInt::tcSet(parts, 0, dstPartsCount);
+ truncatedBits = semantics->precision;
} else {
- if ((unsigned) -bits >= semantics->precision) {
- // Unrepresentably large.
- if (!sign && isSigned)
- APInt::tcSetLeastSignificantBits(parts, partsCount, width-1);
- else if (!sign && !isSigned)
- APInt::tcSetLeastSignificantBits(parts, partsCount, width);
- else if (sign && isSigned) {
- APInt::tcSetLeastSignificantBits(parts, partsCount, 1);
- APInt::tcShiftLeft(parts, partsCount, width-1);
- } else // sign && !isSigned
- APInt::tcSet(parts, 0, partsCount);
- return (opStatus)(opOverflow | opInexact);
+ /* We want the most significant (exponent + 1) bits; the rest are
+ truncated. */
+ unsigned int bits = exponent + 1U;
+
+ /* Hopelessly large in magnitude? */
+ if (bits > width)
+ return opInvalidOp;
+
+ if (bits < semantics->precision) {
+ /* We truncate (semantics->precision - bits) bits. */
+ truncatedBits = semantics->precision - bits;
+ APInt::tcExtract(parts, dstPartsCount, src, bits, truncatedBits);
+ } else {
+ /* We want at least as many bits as are available. */
+ APInt::tcExtract(parts, dstPartsCount, src, semantics->precision, 0);
+ APInt::tcShiftLeft(parts, dstPartsCount, bits - semantics->precision);
+ truncatedBits = 0;
}
- tmp.shiftSignificandLeft(-bits);
+ }
+
+ /* Step 2: work out any lost fraction, and increment the absolute
+ value if we would round away from zero. */
+ if (truncatedBits) {
+ lost_fraction = lostFractionThroughTruncation(src, partCount(),
+ truncatedBits);
+ if (lost_fraction != lfExactlyZero
+ && roundAwayFromZero(rounding_mode, lost_fraction, truncatedBits)) {
+ if (APInt::tcIncrement(parts, dstPartsCount))
+ return opInvalidOp; /* Overflow. */
+ }
+ } else {
lost_fraction = lfExactlyZero;
}
- if(lost_fraction != lfExactlyZero
- && tmp.roundAwayFromZero(rounding_mode, lost_fraction, 0))
- tmp.incrementSignificand();
+ /* Step 3: check if we fit in the destination. */
+ unsigned int omsb = APInt::tcMSB(parts, dstPartsCount) + 1;
- msb = tmp.significandMSB();
+ if (sign) {
+ if (!isSigned) {
+ /* Negative numbers cannot be represented as unsigned. */
+ if (omsb != 0)
+ return opInvalidOp;
+ } else {
+ /* It takes omsb bits to represent the unsigned integer value.
+ We lose a bit for the sign, but care is needed as the
+ maximally negative integer is a special case. */
+ if (omsb == width && APInt::tcLSB(parts, dstPartsCount) + 1 != omsb)
+ return opInvalidOp;
+
+ /* This case can happen because of rounding. */
+ if (omsb > width)
+ return opInvalidOp;
+ }
- /* Negative numbers cannot be represented as unsigned. */
- if(!isSigned && tmp.sign && msb != -1U)
- return opInvalidOp;
+ APInt::tcNegate (parts, dstPartsCount);
+ } else {
+ if (omsb >= width + !isSigned)
+ return opInvalidOp;
+ }
- /* It takes exponent + 1 bits to represent the truncated floating
- point number without its sign. We lose a bit for the sign, but
- the maximally negative integer is a special case. */
- if(msb + 1 > width) /* !! Not same as msb >= width !! */
- return opInvalidOp;
+ if (lost_fraction == lfExactlyZero)
+ return opOK;
+ else
+ return opInexact;
+}
- if(isSigned && msb + 1 == width
- && (!tmp.sign || tmp.significandLSB() != msb))
- return opInvalidOp;
+/* Same as convertToSignExtendedInteger, except we provide
+ deterministic values in case of an invalid operation exception,
+ namely zero for NaNs and the minimal or maximal value respectively
+ for underflow or overflow. */
+APFloat::opStatus
+APFloat::convertToInteger(integerPart *parts, unsigned int width,
+ bool isSigned,
+ roundingMode rounding_mode) const
+{
+ opStatus fs;
- APInt::tcAssign(parts, tmp.significandParts(), partsCount);
+ fs = convertToSignExtendedInteger(parts, width, isSigned, rounding_mode);
- if(tmp.sign)
- APInt::tcNegate(parts, partsCount);
+ if (fs == opInvalidOp) {
+ unsigned int bits, dstPartsCount;
- if(lost_fraction == lfExactlyZero)
- return opOK;
- else
- return opInexact;
+ dstPartsCount = partCountForBits(width);
+
+ if (category == fcNaN)
+ bits = 0;
+ else if (sign)
+ bits = isSigned;
+ else
+ bits = width - isSigned;
+
+ APInt::tcSetLeastSignificantBits(parts, dstPartsCount, bits);
+ if (sign && isSigned)
+ APInt::tcShiftLeft(parts, dstPartsCount, width - 1);
+ }
+
+ return fs;
}
/* Convert an unsigned integer SRC to a floating point number,
return normalize(rounding_mode, lost_fraction);
}
+APFloat::opStatus
+APFloat::convertFromAPInt(const APInt &Val,
+ bool isSigned,
+ roundingMode rounding_mode)
+{
+ unsigned int partCount = Val.getNumWords();
+ APInt api = Val;
+
+ sign = false;
+ if (isSigned && api.isNegative()) {
+ sign = true;
+ api = -api;
+ }
+
+ return convertFromUnsignedParts(api.getRawData(), partCount, rounding_mode);
+}
+
/* Convert a two's complement integer SRC to a floating point number,
rounding according to ROUNDING_MODE. ISSIGNED is true if the
integer is signed, in which case it must be sign-extended. */
42039/12655 < L < 28738/8651 [ numerator <= 65536 ]
*/
- if (*D.firstSigDigit == '0') {
+ if (decDigitValue(*D.firstSigDigit) >= 10U) {
category = fcZero;
fs = opOK;
} else if ((D.normalizedExponent + 1) * 28738
APInt
APFloat::convertF80LongDoubleAPFloatToAPInt() const
{
- assert(semantics == (const llvm::fltSemantics* const)&x87DoubleExtended);
+ assert(semantics == (const llvm::fltSemantics*)&x87DoubleExtended);
assert (partCount()==2);
uint64_t myexponent, mysignificand;
APInt
APFloat::convertPPCDoubleDoubleAPFloatToAPInt() const
{
- assert(semantics == (const llvm::fltSemantics* const)&PPCDoubleDouble);
+ assert(semantics == (const llvm::fltSemantics*)&PPCDoubleDouble);
assert (partCount()==2);
uint64_t myexponent, mysignificand, myexponent2, mysignificand2;
if (category==fcNormal) {
myexponent = exponent+127; //bias
mysignificand = *significandParts();
- if (myexponent == 1 && !(mysignificand & 0x400000))
+ if (myexponent == 1 && !(mysignificand & 0x800000))
myexponent = 0; // denormal
} else if (category==fcZero) {
myexponent = 0;
APInt
APFloat::convertToAPInt() const
{
- if (semantics == (const llvm::fltSemantics* const)&IEEEsingle)
+ if (semantics == (const llvm::fltSemantics*)&IEEEsingle)
return convertFloatAPFloatToAPInt();
- if (semantics == (const llvm::fltSemantics* const)&IEEEdouble)
+ if (semantics == (const llvm::fltSemantics*)&IEEEdouble)
return convertDoubleAPFloatToAPInt();
- if (semantics == (const llvm::fltSemantics* const)&PPCDoubleDouble)
+ if (semantics == (const llvm::fltSemantics*)&PPCDoubleDouble)
return convertPPCDoubleDoubleAPFloatToAPInt();
- assert(semantics == (const llvm::fltSemantics* const)&x87DoubleExtended &&
+ assert(semantics == (const llvm::fltSemantics*)&x87DoubleExtended &&
"unknown format!");
return convertF80LongDoubleAPFloatToAPInt();
}
float
APFloat::convertToFloat() const
{
- assert(semantics == (const llvm::fltSemantics* const)&IEEEsingle);
+ assert(semantics == (const llvm::fltSemantics*)&IEEEsingle);
APInt api = convertToAPInt();
return api.bitsToFloat();
}
double
APFloat::convertToDouble() const
{
- assert(semantics == (const llvm::fltSemantics* const)&IEEEdouble);
+ assert(semantics == (const llvm::fltSemantics*)&IEEEdouble);
APInt api = convertToAPInt();
return api.bitsToDouble();
}
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