/* Number of bits in the significand. This includes the integer
bit. */
- unsigned char precision;
+ unsigned int precision;
- /* If the target format has an implicit integer bit. */
- bool implicitIntegerBit;
+ /* True if arithmetic is supported. */
+ unsigned int arithmeticOK;
};
const fltSemantics APFloat::IEEEsingle = { 127, -126, 24, true };
const fltSemantics APFloat::IEEEdouble = { 1023, -1022, 53, true };
const fltSemantics APFloat::IEEEquad = { 16383, -16382, 113, true };
- const fltSemantics APFloat::x87DoubleExtended = { 16383, -16382, 64, false };
- const fltSemantics APFloat::Bogus = { 0, 0, 0, false };
+ const fltSemantics APFloat::x87DoubleExtended = { 16383, -16382, 64, true };
+ const fltSemantics APFloat::Bogus = { 0, 0, 0, true };
+
+ // The PowerPC format consists of two doubles. It does not map cleanly
+ // onto the usual format above. For now only storage of constants of
+ // this type is supported, no arithmetic.
+ const fltSemantics APFloat::PPCDoubleDouble = { 1023, -1022, 106, false };
+
+ /* A tight upper bound on number of parts required to hold the value
+ pow(5, power) is
+
+ power * 1024 / (441 * integerPartWidth) + 1
+
+ However, whilst the result may require only this many parts,
+ because we are multiplying two values to get it, the
+ multiplication may require an extra part with the excess part
+ being zero (consider the trivial case of 1 * 1, tcFullMultiply
+ requires two parts to hold the single-part result). So we add an
+ extra one to guarantee enough space whilst multiplying. */
+ const unsigned int maxExponent = 16383;
+ const unsigned int maxPrecision = 113;
+ const unsigned int maxPowerOfFiveExponent = maxExponent + maxPrecision - 1;
+ const unsigned int maxPowerOfFiveParts = 2 + ((maxPowerOfFiveExponent * 1024)
+ / (441 * integerPartWidth));
}
/* Put a bunch of private, handy routines in an anonymous namespace. */
return ((bits) + integerPartWidth - 1) / integerPartWidth;
}
- unsigned int
- digitValue(unsigned int c)
+ /* Returns 0U-9U. Return values >= 10U are not digits. */
+ inline unsigned int
+ decDigitValue(unsigned int c)
{
- unsigned int r;
-
- r = c - '0';
- if(r <= 9)
- return r;
-
- return -1U;
+ return c - '0';
}
unsigned int
- hexDigitValue (unsigned int c)
+ hexDigitValue(unsigned int c)
{
unsigned int r;
return -1U;
}
+ inline void
+ assertArithmeticOK(const llvm::fltSemantics &semantics) {
+ assert(semantics.arithmeticOK
+ && "Compile-time arithmetic does not support these semantics");
+ }
+
+ /* Return the value of a decimal exponent of the form
+ [+-]ddddddd.
+
+ If the exponent overflows, returns a large exponent with the
+ appropriate sign. */
+ static int
+ readExponent(const char *p)
+ {
+ bool isNegative;
+ unsigned int absExponent;
+ const unsigned int overlargeExponent = 24000; /* FIXME. */
+
+ isNegative = (*p == '-');
+ if (*p == '-' || *p == '+')
+ p++;
+
+ absExponent = decDigitValue(*p++);
+ assert (absExponent < 10U);
+
+ for (;;) {
+ unsigned int value;
+
+ value = decDigitValue(*p);
+ if (value >= 10U)
+ break;
+
+ p++;
+ value += absExponent * 10;
+ if (absExponent >= overlargeExponent) {
+ absExponent = overlargeExponent;
+ break;
+ }
+ absExponent = value;
+ }
+
+ if (isNegative)
+ return -(int) absExponent;
+ else
+ return (int) absExponent;
+ }
+
/* This is ugly and needs cleaning up, but I don't immediately see
how whilst remaining safe. */
static int
for(;;) {
unsigned int value;
- value = digitValue(*p);
- if(value == -1U)
+ value = decDigitValue(*p);
+ if(value >= 10U)
break;
p++;
return p;
}
+ /* Given a normal decimal floating point number of the form
+
+ dddd.dddd[eE][+-]ddd
+
+ where the decimal point and exponent are optional, fill out the
+ structure D. If the value is zero, V->firstSigDigit
+ points to a zero, and the return exponent is zero. */
+ struct decimalInfo {
+ const char *firstSigDigit;
+ const char *lastSigDigit;
+ int exponent;
+ };
+
+ void
+ interpretDecimal(const char *p, decimalInfo *D)
+ {
+ const char *dot;
+
+ p = skipLeadingZeroesAndAnyDot (p, &dot);
+
+ D->firstSigDigit = p;
+ D->exponent = 0;
+
+ for (;;) {
+ if (*p == '.') {
+ assert(dot == 0);
+ dot = p++;
+ }
+ if (decDigitValue(*p) >= 10U)
+ break;
+ p++;
+ }
+
+ /* If number is all zerooes accept any exponent. */
+ if (p != D->firstSigDigit) {
+ if (*p == 'e' || *p == 'E')
+ D->exponent = readExponent(p + 1);
+
+ /* Implied decimal point? */
+ if (!dot)
+ dot = p;
+
+ /* Drop insignificant trailing zeroes. */
+ do
+ do
+ p--;
+ while (*p == '0');
+ while (*p == '.');
+
+ /* Adjust the specified exponent for any decimal point. */
+ D->exponent += (dot - p) - (dot > p);
+ }
+
+ D->lastSigDigit = p;
+ }
+
/* Return the trailing fraction of a hexadecimal number.
DIGITVALUE is the first hex digit of the fraction, P points to
the next digit. */
return moreSignificant;
}
+ /* The error from the true value, in half-ulps, on multiplying two
+ floating point numbers, which differ from the value they
+ approximate by at most HUE1 and HUE2 half-ulps, is strictly less
+ than the returned value.
+
+ See "How to Read Floating Point Numbers Accurately" by William D
+ Clinger. */
+ unsigned int
+ HUerrBound(bool inexactMultiply, unsigned int HUerr1, unsigned int HUerr2)
+ {
+ assert(HUerr1 < 2 || HUerr2 < 2 || (HUerr1 + HUerr2 < 8));
+
+ if (HUerr1 + HUerr2 == 0)
+ return inexactMultiply * 2; /* <= inexactMultiply half-ulps. */
+ else
+ return inexactMultiply + 2 * (HUerr1 + HUerr2);
+ }
+
+ /* The number of ulps from the boundary (zero, or half if ISNEAREST)
+ when the least significant BITS are truncated. BITS cannot be
+ zero. */
+ integerPart
+ ulpsFromBoundary(const integerPart *parts, unsigned int bits, bool isNearest)
+ {
+ unsigned int count, partBits;
+ integerPart part, boundary;
+
+ assert (bits != 0);
+
+ bits--;
+ count = bits / integerPartWidth;
+ partBits = bits % integerPartWidth + 1;
+
+ part = parts[count] & (~(integerPart) 0 >> (integerPartWidth - partBits));
+
+ if (isNearest)
+ boundary = (integerPart) 1 << (partBits - 1);
+ else
+ boundary = 0;
+
+ if (count == 0) {
+ if (part - boundary <= boundary - part)
+ return part - boundary;
+ else
+ return boundary - part;
+ }
+
+ if (part == boundary) {
+ while (--count)
+ if (parts[count])
+ return ~(integerPart) 0; /* A lot. */
+
+ return parts[0];
+ } else if (part == boundary - 1) {
+ while (--count)
+ if (~parts[count])
+ return ~(integerPart) 0; /* A lot. */
+
+ return -parts[0];
+ }
+
+ return ~(integerPart) 0; /* A lot. */
+ }
+
+ /* 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
+ powerOf5(integerPart *dst, unsigned int power)
+ {
+ static integerPart firstEightPowers[] = { 1, 5, 25, 125, 625, 3125,
+ 15625, 78125 };
+ static integerPart pow5s[maxPowerOfFiveParts * 2 + 5] = { 78125 * 5 };
+ static unsigned int partsCount[16] = { 1 };
+
+ integerPart scratch[maxPowerOfFiveParts], *p1, *p2, *pow5;
+ unsigned int result;
+
+ assert(power <= maxExponent);
+
+ p1 = dst;
+ p2 = scratch;
+
+ *p1 = firstEightPowers[power & 7];
+ power >>= 3;
+
+ result = 1;
+ pow5 = pow5s;
+
+ for (unsigned int n = 0; power; power >>= 1, n++) {
+ unsigned int pc;
+
+ pc = partsCount[n];
+
+ /* Calculate pow(5,pow(2,n+3)) if we haven't yet. */
+ if (pc == 0) {
+ pc = partsCount[n - 1];
+ APInt::tcFullMultiply(pow5, pow5 - pc, pow5 - pc, pc, pc);
+ pc *= 2;
+ if (pow5[pc - 1] == 0)
+ pc--;
+ partsCount[n] = pc;
+ }
+
+ if (power & 1) {
+ integerPart *tmp;
+
+ APInt::tcFullMultiply(p2, p1, pow5, result, pc);
+ result += pc;
+ if (p2[result - 1] == 0)
+ result--;
+
+ /* Now result is in p1 with partsCount parts and p2 is scratch
+ space. */
+ tmp = p1, p1 = p2, p2 = tmp;
+ }
+
+ pow5 += pc;
+ }
+
+ if (p1 != dst)
+ APInt::tcAssign(dst, p1, result);
+
+ return result;
+ }
+
/* Zero at the end to avoid modular arithmetic when adding one; used
when rounding up during hexadecimal output. */
static const char hexDigitsLower[] = "0123456789abcdef0";
sign = rhs.sign;
category = rhs.category;
exponent = rhs.exponent;
+ sign2 = rhs.sign2;
+ exponent2 = rhs.exponent2;
if(category == fcNormal || category == fcNaN)
copySignificand(rhs);
}
partCount());
}
+/* Make this number a NaN, with an arbitrary but deterministic value
+ for the significand. */
+void
+APFloat::makeNaN(void)
+{
+ category = fcNaN;
+ APInt::tcSet(significandParts(), ~0U, partCount());
+}
+
APFloat &
APFloat::operator=(const APFloat &rhs)
{
category != rhs.category ||
sign != rhs.sign)
return false;
+ if (semantics==(const llvm::fltSemantics* const)&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 &&
+ exponent2!=rhs.exponent2)
+ return false;
else {
int i= partCount();
const integerPart* p=significandParts();
APFloat::APFloat(const fltSemantics &ourSemantics, integerPart value)
{
+ assertArithmeticOK(ourSemantics);
initialize(&ourSemantics);
sign = 0;
zeroSignificand();
APFloat::APFloat(const fltSemantics &ourSemantics,
fltCategory ourCategory, bool negative)
{
+ assertArithmeticOK(ourSemantics);
initialize(&ourSemantics);
category = ourCategory;
sign = negative;
if(category == fcNormal)
category = fcZero;
+ else if (ourCategory == fcNaN)
+ makeNaN();
}
APFloat::APFloat(const fltSemantics &ourSemantics, const char *text)
{
+ assertArithmeticOK(ourSemantics);
initialize(&ourSemantics);
convertFromString(text, rmNearestTiesToEven);
}
APInt::tcShiftLeft(dividend, partsCount, bit);
}
+ /* Ensure the dividend >= divisor initially for the loop below.
+ Incidentally, this means that the division loop below is
+ guaranteed to set the integer bit to one. */
if(APInt::tcCompare(dividend, divisor, partsCount) < 0) {
exponent--;
APInt::tcShiftLeft(dividend, partsCount, 1);
/* Keep OMSB up-to-date. */
if(omsb > (unsigned) exponentChange)
- omsb -= (unsigned) exponentChange;
+ omsb -= exponentChange;
else
omsb = 0;
}
/* We have a non-zero denormal. */
assert(omsb < semantics->precision);
- assert(exponent == semantics->minExponent);
/* Canonicalize zeroes. */
if(omsb == 0)
/* Differently signed infinities can only be validly
subtracted. */
if(sign ^ rhs.sign != subtract) {
- category = fcNaN;
- // Arbitrary but deterministic value for significand
- APInt::tcSet(significandParts(), ~0U, partCount());
+ makeNaN();
return opInvalidOp;
}
case convolve(fcZero, fcInfinity):
case convolve(fcInfinity, fcZero):
- category = fcNaN;
- // Arbitrary but deterministic value for significand
- APInt::tcSet(significandParts(), ~0U, partCount());
+ makeNaN();
return opInvalidOp;
case convolve(fcNormal, fcNormal):
case convolve(fcInfinity, fcInfinity):
case convolve(fcZero, fcZero):
- category = fcNaN;
- // Arbitrary but deterministic value for significand
- APInt::tcSet(significandParts(), ~0U, partCount());
+ makeNaN();
return opInvalidOp;
case convolve(fcNormal, fcNormal):
{
opStatus fs;
+ assertArithmeticOK(*semantics);
+
fs = addOrSubtractSpecials(rhs, subtract);
/* This return code means it was not a simple case. */
{
opStatus fs;
+ assertArithmeticOK(*semantics);
sign ^= rhs.sign;
fs = multiplySpecials(rhs);
{
opStatus fs;
+ assertArithmeticOK(*semantics);
sign ^= rhs.sign;
fs = divideSpecials(rhs);
opStatus fs;
APFloat V = *this;
unsigned int origSign = sign;
+
+ assertArithmeticOK(*semantics);
fs = V.divide(rhs, rmNearestTiesToEven);
if (fs == opDivByZero)
return fs;
{
opStatus fs;
+ assertArithmeticOK(*semantics);
+
/* Post-multiplication sign, before addition. */
sign ^= multiplicand.sign;
{
cmpResult result;
+ assertArithmeticOK(*semantics);
assert(semantics == rhs.semantics);
switch(convolve(category, rhs.category)) {
unsigned int newPartCount, oldPartCount;
opStatus fs;
+ assertArithmeticOK(*semantics);
lostFraction = lfExactlyZero;
newPartCount = partCountForBits(toSemantics.precision + 1);
oldPartCount = partCount();
unsigned int msb, partsCount;
int bits;
+ assertArithmeticOK(*semantics);
partsCount = partCountForBits(width);
/* Handle the three special cases first. We produce
if(bits > 0) {
lost_fraction = tmp.shiftSignificandRight(bits);
} else {
- if (-bits >= semantics->precision) {
+ if ((unsigned) -bits >= semantics->precision) {
// Unrepresentably large.
if (!sign && isSigned)
APInt::tcSetLeastSignificantBits(parts, partsCount, width-1);
unsigned int srcCount,
roundingMode rounding_mode)
{
- unsigned int dstCount;
- lostFraction lost_fraction;
+ unsigned int omsb, precision, dstCount;
integerPart *dst;
+ lostFraction lost_fraction;
+ assertArithmeticOK(*semantics);
category = fcNormal;
- exponent = semantics->precision - 1;
-
+ omsb = APInt::tcMSB(src, srcCount) + 1;
dst = significandParts();
dstCount = partCount();
+ precision = semantics->precision;
- /* We need to capture the non-zero most significant parts. */
- while (srcCount > dstCount && src[srcCount - 1] == 0)
- srcCount--;
-
- /* Copy the bit image of as many parts as we can. If we are wider,
- zero-out remaining parts. */
- if (dstCount >= srcCount) {
- APInt::tcAssign(dst, src, srcCount);
- while (srcCount < dstCount)
- dst[srcCount++] = 0;
- lost_fraction = lfExactlyZero;
- } else {
- exponent += (srcCount - dstCount) * integerPartWidth;
- APInt::tcAssign(dst, src + (srcCount - dstCount), dstCount);
+ /* We want the most significant PRECISON bits of SRC. There may not
+ be that many; extract what we can. */
+ if (precision <= omsb) {
+ exponent = omsb - 1;
lost_fraction = lostFractionThroughTruncation(src, srcCount,
- dstCount * integerPartWidth);
+ omsb - precision);
+ APInt::tcExtract(dst, dstCount, src, precision, omsb - precision);
+ } else {
+ exponent = precision - 1;
+ lost_fraction = lfExactlyZero;
+ APInt::tcExtract(dst, dstCount, src, omsb, 0);
}
return normalize(rounding_mode, lost_fraction);
{
opStatus status;
+ assertArithmeticOK(*semantics);
if (isSigned
&& APInt::tcExtractBit(src, srcCount * integerPartWidth - 1)) {
integerPart *copy;
return normalize(rounding_mode, lost_fraction);
}
+APFloat::opStatus
+APFloat::roundSignificandWithExponent(const integerPart *decSigParts,
+ unsigned sigPartCount, int exp,
+ roundingMode rounding_mode)
+{
+ unsigned int parts, pow5PartCount;
+ fltSemantics calcSemantics = { 32767, -32767, 0, true };
+ integerPart pow5Parts[maxPowerOfFiveParts];
+ bool isNearest;
+
+ isNearest = (rounding_mode == rmNearestTiesToEven
+ || rounding_mode == rmNearestTiesToAway);
+
+ parts = partCountForBits(semantics->precision + 11);
+
+ /* Calculate pow(5, abs(exp)). */
+ pow5PartCount = powerOf5(pow5Parts, exp >= 0 ? exp: -exp);
+
+ for (;; parts *= 2) {
+ opStatus sigStatus, powStatus;
+ unsigned int excessPrecision, truncatedBits;
+
+ calcSemantics.precision = parts * integerPartWidth - 1;
+ excessPrecision = calcSemantics.precision - semantics->precision;
+ truncatedBits = excessPrecision;
+
+ APFloat decSig(calcSemantics, fcZero, sign);
+ APFloat pow5(calcSemantics, fcZero, false);
+
+ sigStatus = decSig.convertFromUnsignedParts(decSigParts, sigPartCount,
+ rmNearestTiesToEven);
+ powStatus = pow5.convertFromUnsignedParts(pow5Parts, pow5PartCount,
+ rmNearestTiesToEven);
+ /* Add exp, as 10^n = 5^n * 2^n. */
+ decSig.exponent += exp;
+
+ lostFraction calcLostFraction;
+ integerPart HUerr, HUdistance, powHUerr;
+
+ if (exp >= 0) {
+ /* multiplySignificand leaves the precision-th bit set to 1. */
+ calcLostFraction = decSig.multiplySignificand(pow5, NULL);
+ powHUerr = powStatus != opOK;
+ } else {
+ calcLostFraction = decSig.divideSignificand(pow5);
+ /* Denormal numbers have less precision. */
+ if (decSig.exponent < semantics->minExponent) {
+ excessPrecision += (semantics->minExponent - decSig.exponent);
+ truncatedBits = excessPrecision;
+ if (excessPrecision > calcSemantics.precision)
+ excessPrecision = calcSemantics.precision;
+ }
+ /* Extra half-ulp lost in reciprocal of exponent. */
+ powHUerr = (powStatus == opOK && calcLostFraction == lfExactlyZero) ? 0: 2;
+ }
+
+ /* Both multiplySignificand and divideSignificand return the
+ result with the integer bit set. */
+ assert (APInt::tcExtractBit
+ (decSig.significandParts(), calcSemantics.precision - 1) == 1);
+
+ HUerr = HUerrBound(calcLostFraction != lfExactlyZero, sigStatus != opOK,
+ powHUerr);
+ HUdistance = 2 * ulpsFromBoundary(decSig.significandParts(),
+ excessPrecision, isNearest);
+
+ /* Are we guaranteed to round correctly if we truncate? */
+ if (HUdistance >= HUerr) {
+ APInt::tcExtract(significandParts(), partCount(), decSig.significandParts(),
+ calcSemantics.precision - excessPrecision,
+ excessPrecision);
+ /* Take the exponent of decSig. If we tcExtract-ed less bits
+ above we must adjust our exponent to compensate for the
+ implicit right shift. */
+ exponent = (decSig.exponent + semantics->precision
+ - (calcSemantics.precision - excessPrecision));
+ calcLostFraction = lostFractionThroughTruncation(decSig.significandParts(),
+ decSig.partCount(),
+ truncatedBits);
+ return normalize(rounding_mode, calcLostFraction);
+ }
+ }
+}
+
+APFloat::opStatus
+APFloat::convertFromDecimalString(const char *p, roundingMode rounding_mode)
+{
+ decimalInfo D;
+ opStatus fs;
+
+ /* Scan the text. */
+ interpretDecimal(p, &D);
+
+ if (*D.firstSigDigit == '0') {
+ category = fcZero;
+ fs = opOK;
+ } else {
+ integerPart *decSignificand;
+ unsigned int partCount;
+
+ /* A tight upper bound on number of bits required to hold an
+ N-digit decimal integer is N * 256 / 77. Allocate enough space
+ to hold the full significand, and an extra part required by
+ tcMultiplyPart. */
+ partCount = (D.lastSigDigit - D.firstSigDigit) + 1;
+ partCount = partCountForBits(1 + 256 * partCount / 77);
+ decSignificand = new integerPart[partCount + 1];
+ partCount = 0;
+
+ /* Convert to binary efficiently - we do almost all multiplication
+ in an integerPart. When this would overflow do we do a single
+ bignum multiplication, and then revert again to multiplication
+ in an integerPart. */
+ do {
+ integerPart decValue, val, multiplier;
+
+ val = 0;
+ multiplier = 1;
+
+ do {
+ if (*p == '.')
+ p++;
+
+ decValue = decDigitValue(*p++);
+ multiplier *= 10;
+ val = val * 10 + decValue;
+ /* The maximum number that can be multiplied by ten with any
+ digit added without overflowing an integerPart. */
+ } while (p <= D.lastSigDigit && multiplier <= (~ (integerPart) 0 - 9) / 10);
+
+ /* Multiply out the current part. */
+ APInt::tcMultiplyPart(decSignificand, decSignificand, multiplier, val,
+ partCount, partCount + 1, false);
+
+ /* If we used another part (likely but not guaranteed), increase
+ the count. */
+ if (decSignificand[partCount])
+ partCount++;
+ } while (p <= D.lastSigDigit);
+
+ category = fcNormal;
+ fs = roundSignificandWithExponent(decSignificand, partCount,
+ D.exponent, rounding_mode);
+
+ delete [] decSignificand;
+ }
+
+ return fs;
+}
+
APFloat::opStatus
APFloat::convertFromString(const char *p, roundingMode rounding_mode)
{
+ assertArithmeticOK(*semantics);
+
/* Handle a leading minus sign. */
if(*p == '-')
sign = 1, p++;
if(p[0] == '0' && (p[1] == 'x' || p[1] == 'X'))
return convertFromHexadecimalString(p + 2, rounding_mode);
-
- assert(0 && "Decimal to binary conversions not yet implemented");
- abort();
+ else
+ return convertFromDecimalString(p, rounding_mode);
}
/* Write out a hexadecimal representation of the floating point value
{
char *p;
+ assertArithmeticOK(*semantics);
+
p = dst;
if (sign)
*dst++ = '-';
return APInt(80, 2, words);
}
+APInt
+APFloat::convertPPCDoubleDoubleAPFloatToAPInt() const
+{
+ assert(semantics == (const llvm::fltSemantics* const)&PPCDoubleDouble);
+ assert (partCount()==2);
+
+ uint64_t myexponent, mysignificand, myexponent2, mysignificand2;
+
+ if (category==fcNormal) {
+ myexponent = exponent + 1023; //bias
+ myexponent2 = exponent2 + 1023;
+ mysignificand = significandParts()[0];
+ mysignificand2 = significandParts()[1];
+ if (myexponent==1 && !(mysignificand & 0x10000000000000LL))
+ myexponent = 0; // denormal
+ if (myexponent2==1 && !(mysignificand2 & 0x10000000000000LL))
+ myexponent2 = 0; // denormal
+ } else if (category==fcZero) {
+ myexponent = 0;
+ mysignificand = 0;
+ myexponent2 = 0;
+ mysignificand2 = 0;
+ } else if (category==fcInfinity) {
+ myexponent = 0x7ff;
+ myexponent2 = 0;
+ mysignificand = 0;
+ mysignificand2 = 0;
+ } else {
+ assert(category == fcNaN && "Unknown category");
+ myexponent = 0x7ff;
+ mysignificand = significandParts()[0];
+ myexponent2 = exponent2;
+ mysignificand2 = significandParts()[1];
+ }
+
+ uint64_t words[2];
+ words[0] = (((uint64_t)sign & 1) << 63) |
+ ((myexponent & 0x7ff) << 52) |
+ (mysignificand & 0xfffffffffffffLL);
+ words[1] = (((uint64_t)sign2 & 1) << 63) |
+ ((myexponent2 & 0x7ff) << 52) |
+ (mysignificand2 & 0xfffffffffffffLL);
+ return APInt(128, 2, words);
+}
+
APInt
APFloat::convertDoubleAPFloatToAPInt() const
{
(mysignificand & 0x7fffff)));
}
+// This function creates an APInt that is just a bit map of the floating
+// point constant as it would appear in memory. It is not a conversion,
+// and treating the result as a normal integer is unlikely to be useful.
+
APInt
APFloat::convertToAPInt() const
{
if (semantics == (const llvm::fltSemantics* const)&IEEEdouble)
return convertDoubleAPFloatToAPInt();
+ if (semantics == (const llvm::fltSemantics* const)&PPCDoubleDouble)
+ return convertPPCDoubleDoubleAPFloatToAPInt();
+
assert(semantics == (const llvm::fltSemantics* const)&x87DoubleExtended &&
"unknown format!");
return convertF80LongDoubleAPFloatToAPInt();
}
}
+void
+APFloat::initFromPPCDoubleDoubleAPInt(const APInt &api)
+{
+ assert(api.getBitWidth()==128);
+ uint64_t i1 = api.getRawData()[0];
+ uint64_t i2 = api.getRawData()[1];
+ uint64_t myexponent = (i1 >> 52) & 0x7ff;
+ uint64_t mysignificand = i1 & 0xfffffffffffffLL;
+ uint64_t myexponent2 = (i2 >> 52) & 0x7ff;
+ uint64_t mysignificand2 = i2 & 0xfffffffffffffLL;
+
+ initialize(&APFloat::PPCDoubleDouble);
+ assert(partCount()==2);
+
+ sign = i1>>63;
+ sign2 = i2>>63;
+ if (myexponent==0 && mysignificand==0) {
+ // exponent, significand meaningless
+ // exponent2 and significand2 are required to be 0; we don't check
+ category = fcZero;
+ } else if (myexponent==0x7ff && mysignificand==0) {
+ // exponent, significand meaningless
+ // exponent2 and significand2 are required to be 0; we don't check
+ category = fcInfinity;
+ } else if (myexponent==0x7ff && mysignificand!=0) {
+ // exponent meaningless. So is the whole second word, but keep it
+ // for determinism.
+ category = fcNaN;
+ exponent2 = myexponent2;
+ significandParts()[0] = mysignificand;
+ significandParts()[1] = mysignificand2;
+ } else {
+ category = fcNormal;
+ // Note there is no category2; the second word is treated as if it is
+ // fcNormal, although it might be something else considered by itself.
+ exponent = myexponent - 1023;
+ exponent2 = myexponent2 - 1023;
+ significandParts()[0] = mysignificand;
+ significandParts()[1] = mysignificand2;
+ if (myexponent==0) // denormal
+ exponent = -1022;
+ else
+ significandParts()[0] |= 0x10000000000000LL; // integer bit
+ if (myexponent2==0)
+ exponent2 = -1022;
+ else
+ significandParts()[1] |= 0x10000000000000LL; // integer bit
+ }
+}
+
void
APFloat::initFromDoubleAPInt(const APInt &api)
{
}
/// Treat api as containing the bits of a floating point number. Currently
-/// we infer the floating point type from the size of the APInt. FIXME: This
-/// breaks when we get to PPC128 and IEEE128 (but both cannot exist in the
-/// same compile...)
+/// we infer the floating point type from the size of the APInt. The
+/// isIEEE argument distinguishes between PPC128 and IEEE128 (not meaningful
+/// when the size is anything else).
void
-APFloat::initFromAPInt(const APInt& api)
+APFloat::initFromAPInt(const APInt& api, bool isIEEE)
{
if (api.getBitWidth() == 32)
return initFromFloatAPInt(api);
return initFromDoubleAPInt(api);
else if (api.getBitWidth()==80)
return initFromF80LongDoubleAPInt(api);
+ else if (api.getBitWidth()==128 && !isIEEE)
+ return initFromPPCDoubleDoubleAPInt(api);
else
assert(0);
}
-APFloat::APFloat(const APInt& api)
+APFloat::APFloat(const APInt& api, bool isIEEE)
{
- initFromAPInt(api);
+ initFromAPInt(api, isIEEE);
}
APFloat::APFloat(float f)