qzdoom-gpl/gdtoa/gdtoa.c
Randy Heit fb50df2c63 About a week's worth of changes here. As a heads-up, I wouldn't be
surprised if this doesn't build in Linux right now. The CMakeLists.txt
were checked with MinGW and NMake, but how they fair under Linux is an
unknown to me at this time.

- Converted most sprintf (and all wsprintf) calls to either mysnprintf or
  FStrings, depending on the situation.
- Changed the strings in the wbstartstruct to be FStrings.
- Changed myvsnprintf() to output nothing if count is greater than INT_MAX.
  This is so that I can use a series of mysnprintf() calls and advance the
  pointer for each one. Once the pointer goes beyond the end of the buffer,
  the count will go negative, but since it's an unsigned type it will be
  seen as excessively huge instead. This should not be a problem, as there's
  no reason for ZDoom to be using text buffers larger than 2 GB anywhere.
- Ripped out the disabled bit from FGameConfigFile::MigrateOldConfig().
- Changed CalcMapName() to return an FString instead of a pointer to a static
  buffer.
- Changed startmap in d_main.cpp into an FString.
- Changed CheckWarpTransMap() to take an FString& as the first argument.
- Changed d_mapname in g_level.cpp into an FString.
- Changed DoSubstitution() in ct_chat.cpp to place the substitutions in an
  FString.
- Fixed: The MAPINFO parser wrote into the string buffer to construct a map
  name when given a Hexen map number. This was fine with the old scanner
  code, but only a happy coincidence prevents it from crashing with the new
  code
- Added the 'B' conversion specifier to StringFormat::VWorker() for printing
  binary numbers.
- Added CMake support for building with MinGW, MSYS, and NMake. Linux support
  is probably broken until I get around to booting into Linux again. Niceties
  provided over the existing Makefiles they're replacing:
  * All command-line builds can use the same build system, rather than having
    a separate one for MinGW and another for Linux.
  * Microsoft's NMake tool is supported as a target.
  * Progress meters.
  * Parallel makes work from a fresh checkout without needing to be primed
    first with a single-threaded make.
  * Porting to other architectures should be simplified, whenever that day
    comes.
- Replaced the makewad tool with zipdir. This handles the dependency tracking
  itself instead of generating an external makefile to do it, since I couldn't
  figure out how to generate a makefile with an external tool and include it
  with a CMake-generated makefile. Where makewad used a master list of files
  to generate the package file, zipdir just zips the entire contents of one or
  more directories.
- Added the gdtoa package from netlib's fp library so that ZDoom's printf-style
  formatting can be entirely independant of the CRT.

SVN r1082 (trunk)
2008-07-23 04:57:26 +00:00

759 lines
17 KiB
C

/****************************************************************
The author of this software is David M. Gay.
Copyright (C) 1998, 1999 by Lucent Technologies
All Rights Reserved
Permission to use, copy, modify, and distribute this software and
its documentation for any purpose and without fee is hereby
granted, provided that the above copyright notice appear in all
copies and that both that the copyright notice and this
permission notice and warranty disclaimer appear in supporting
documentation, and that the name of Lucent or any of its entities
not be used in advertising or publicity pertaining to
distribution of the software without specific, written prior
permission.
LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
THIS SOFTWARE.
****************************************************************/
/* Please send bug reports to David M. Gay (dmg at acm dot org,
* with " at " changed at "@" and " dot " changed to "."). */
#include "gdtoaimp.h"
#include <limits.h>
static Bigint *
#ifdef KR_headers
bitstob(bits, nbits, bbits) ULong *bits; int nbits; int *bbits;
#else
bitstob(ULong *bits, int nbits, int *bbits)
#endif
{
int i, k;
Bigint *b;
ULong *be, *x, *x0;
i = ULbits;
k = 0;
while(i < nbits) {
i <<= 1;
k++;
}
#ifndef Pack_32
if (!k)
k = 1;
#endif
b = Balloc(k);
be = bits + ((nbits - 1) >> kshift);
x = x0 = b->x;
do {
*x++ = *bits & ALL_ON;
#ifdef Pack_16
*x++ = (*bits >> 16) & ALL_ON;
#endif
} while(++bits <= be);
i = (int)(x - x0);
while(!x0[--i])
if (!i) {
b->wds = 0;
*bbits = 0;
goto ret;
}
b->wds = i + 1;
*bbits = i*ULbits + 32 - hi0bits(b->x[i]);
ret:
return b;
}
/* dtoa for IEEE arithmetic (dmg): convert double to ASCII string.
*
* Inspired by "How to Print Floating-Point Numbers Accurately" by
* Guy L. Steele, Jr. and Jon L. White [Proc. ACM SIGPLAN '90, pp. 112-126].
*
* Modifications:
* 1. Rather than iterating, we use a simple numeric overestimate
* to determine k = floor(log10(d)). We scale relevant
* quantities using O(log2(k)) rather than O(k) multiplications.
* 2. For some modes > 2 (corresponding to ecvt and fcvt), we don't
* try to generate digits strictly left to right. Instead, we
* compute with fewer bits and propagate the carry if necessary
* when rounding the final digit up. This is often faster.
* 3. Under the assumption that input will be rounded nearest,
* mode 0 renders 1e23 as 1e23 rather than 9.999999999999999e22.
* That is, we allow equality in stopping tests when the
* round-nearest rule will give the same floating-point value
* as would satisfaction of the stopping test with strict
* inequality.
* 4. We remove common factors of powers of 2 from relevant
* quantities.
* 5. When converting floating-point integers less than 1e16,
* we use floating-point arithmetic rather than resorting
* to multiple-precision integers.
* 6. When asked to produce fewer than 15 digits, we first try
* to get by with floating-point arithmetic; we resort to
* multiple-precision integer arithmetic only if we cannot
* guarantee that the floating-point calculation has given
* the correctly rounded result. For k requested digits and
* "uniformly" distributed input, the probability is
* something like 10^(k-15) that we must resort to the Long
* calculation.
*/
char *
gdtoa
#ifdef KR_headers
(fpi, be, bits, kindp, mode, ndigits, decpt, rve)
FPI *fpi; int be; ULong *bits;
int *kindp, mode, ndigits, *decpt; char **rve;
#else
(CONST FPI *fpi, int be, ULong *bits, int *kindp, int mode, int ndigits, int *decpt, char **rve)
#endif
{
/* Arguments ndigits and decpt are similar to the second and third
arguments of ecvt and fcvt; trailing zeros are suppressed from
the returned string. If not null, *rve is set to point
to the end of the return value. If d is +-Infinity or NaN,
then *decpt is set to INT_MAX.
mode:
0 ==> shortest string that yields d when read in
and rounded to nearest.
1 ==> like 0, but with Steele & White stopping rule;
e.g. with IEEE P754 arithmetic , mode 0 gives
1e23 whereas mode 1 gives 9.999999999999999e22.
2 ==> max(1,ndigits) significant digits. This gives a
return value similar to that of ecvt, except
that trailing zeros are suppressed.
3 ==> through ndigits past the decimal point. This
gives a return value similar to that from fcvt,
except that trailing zeros are suppressed, and
ndigits can be negative.
4-9 should give the same return values as 2-3, i.e.,
4 <= mode <= 9 ==> same return as mode
2 + (mode & 1). These modes are mainly for
debugging; often they run slower but sometimes
faster than modes 2-3.
4,5,8,9 ==> left-to-right digit generation.
6-9 ==> don't try fast floating-point estimate
(if applicable).
Values of mode other than 0-9 are treated as mode 0.
Sufficient space is allocated to the return value
to hold the suppressed trailing zeros.
*/
int bbits, b2, b5, be0, dig, i, ieps, ilim, ilim0, ilim1, inex;
int j, j1, k, k0, k_check, kind, leftright, m2, m5, nbits;
int rdir, s2, s5, spec_case, try_quick;
Long L;
Bigint *b, *b1, *delta, *mlo, *mhi, *mhi1, *S;
double d, d2, ds, eps;
char *s, *s0;
#ifndef MULTIPLE_THREADS
if (dtoa_result) {
freedtoa(dtoa_result);
dtoa_result = 0;
}
#endif
inex = 0;
kind = *kindp &= ~STRTOG_Inexact;
switch(kind & STRTOG_Retmask) {
case STRTOG_Zero:
goto ret_zero;
case STRTOG_Normal:
case STRTOG_Denormal:
break;
case STRTOG_Infinite:
*decpt = INT_MAX;
return nrv_alloc("Infinity", rve, 8);
case STRTOG_NaN:
*decpt = INT_MAX;
return nrv_alloc("NaN", rve, 3);
default:
return 0;
}
b = bitstob(bits, nbits = fpi->nbits, &bbits);
be0 = be;
if ( (i = trailz(b)) !=0) {
rshift(b, i);
be += i;
bbits -= i;
}
if (!b->wds) {
Bfree(b);
ret_zero:
*decpt = 1;
return nrv_alloc("0", rve, 1);
}
dval(d) = b2d(b, &i);
i = be + bbits - 1;
word0(d) &= Frac_mask1;
word0(d) |= Exp_11;
#ifdef IBM
if ( (j = 11 - hi0bits(word0(d) & Frac_mask)) !=0)
dval(d) /= 1 << j;
#endif
/* log(x) ~=~ log(1.5) + (x-1.5)/1.5
* log10(x) = log(x) / log(10)
* ~=~ log(1.5)/log(10) + (x-1.5)/(1.5*log(10))
* log10(d) = (i-Bias)*log(2)/log(10) + log10(d2)
*
* This suggests computing an approximation k to log10(d) by
*
* k = (i - Bias)*0.301029995663981
* + ( (d2-1.5)*0.289529654602168 + 0.176091259055681 );
*
* We want k to be too large rather than too small.
* The error in the first-order Taylor series approximation
* is in our favor, so we just round up the constant enough
* to compensate for any error in the multiplication of
* (i - Bias) by 0.301029995663981; since |i - Bias| <= 1077,
* and 1077 * 0.30103 * 2^-52 ~=~ 7.2e-14,
* adding 1e-13 to the constant term more than suffices.
* Hence we adjust the constant term to 0.1760912590558.
* (We could get a more accurate k by invoking log10,
* but this is probably not worthwhile.)
*/
#ifdef IBM
i <<= 2;
i += j;
#endif
ds = (dval(d)-1.5)*0.289529654602168 + 0.1760912590558 + i*0.301029995663981;
/* correct assumption about exponent range */
if ((j = i) < 0)
j = -j;
if ((j -= 1077) > 0)
ds += j * 7e-17;
k = (int)ds;
if (ds < 0. && ds != k)
k--; /* want k = floor(ds) */
k_check = 1;
#ifdef IBM
j = be + bbits - 1;
if ( (j1 = j & 3) !=0)
dval(d) *= 1 << j1;
word0(d) += j << Exp_shift - 2 & Exp_mask;
#else
word0(d) += (be + bbits - 1) << Exp_shift;
#endif
if (k >= 0 && k <= Ten_pmax) {
if (dval(d) < tens[k])
k--;
k_check = 0;
}
j = bbits - i - 1;
if (j >= 0) {
b2 = 0;
s2 = j;
}
else {
b2 = -j;
s2 = 0;
}
if (k >= 0) {
b5 = 0;
s5 = k;
s2 += k;
}
else {
b2 -= k;
b5 = -k;
s5 = 0;
}
if (mode < 0 || mode > 9)
mode = 0;
try_quick = 1;
if (mode > 5) {
mode -= 4;
try_quick = 0;
}
leftright = 1;
switch(mode) {
case 0:
case 1:
ilim = ilim1 = -1;
i = (int)(nbits * .30103) + 3;
ndigits = 0;
break;
case 2:
leftright = 0;
/* no break */
case 4:
if (ndigits <= 0)
ndigits = 1;
ilim = ilim1 = i = ndigits;
break;
case 3:
leftright = 0;
/* no break */
case 5:
i = ndigits + k + 1;
ilim = i;
ilim1 = i - 1;
if (i <= 0)
i = 1;
}
s = s0 = rv_alloc(i);
if ( (rdir = fpi->rounding - 1) !=0) {
if (rdir < 0)
rdir = 2;
if (kind & STRTOG_Neg)
rdir = 3 - rdir;
}
/* Now rdir = 0 ==> round near, 1 ==> round up, 2 ==> round down. */
if (ilim >= 0 && ilim <= Quick_max && try_quick && !rdir
#ifndef IMPRECISE_INEXACT
&& k == 0
#endif
) {
/* Try to get by with floating-point arithmetic. */
i = 0;
d2 = dval(d);
#ifdef IBM
if ( (j = 11 - hi0bits(word0(d) & Frac_mask)) !=0)
dval(d) /= 1 << j;
#endif
k0 = k;
ilim0 = ilim;
ieps = 2; /* conservative */
if (k > 0) {
ds = tens[k&0xf];
j = k >> 4;
if (j & Bletch) {
/* prevent overflows */
j &= Bletch - 1;
dval(d) /= bigtens[n_bigtens-1];
ieps++;
}
for(; j; j >>= 1, i++)
if (j & 1) {
ieps++;
ds *= bigtens[i];
}
}
else {
ds = 1.;
if ( (j1 = -k) !=0) {
dval(d) *= tens[j1 & 0xf];
for(j = j1 >> 4; j; j >>= 1, i++)
if (j & 1) {
ieps++;
dval(d) *= bigtens[i];
}
}
}
if (k_check && dval(d) < 1. && ilim > 0) {
if (ilim1 <= 0)
goto fast_failed;
ilim = ilim1;
k--;
dval(d) *= 10.;
ieps++;
}
dval(eps) = ieps*dval(d) + 7.;
word0(eps) -= (P-1)*Exp_msk1;
if (ilim == 0) {
S = mhi = 0;
dval(d) -= 5.;
if (dval(d) > dval(eps))
goto one_digit;
if (dval(d) < -dval(eps))
goto no_digits;
goto fast_failed;
}
#ifndef No_leftright
if (leftright) {
/* Use Steele & White method of only
* generating digits needed.
*/
dval(eps) = ds*0.5/tens[ilim-1] - dval(eps);
for(i = 0;;) {
L = (Long)(dval(d)/ds);
dval(d) -= L*ds;
*s++ = '0' + (int)L;
if (dval(d) < dval(eps)) {
if (dval(d))
inex = STRTOG_Inexlo;
goto ret1;
}
if (ds - dval(d) < dval(eps))
goto bump_up;
if (++i >= ilim)
break;
dval(eps) *= 10.;
dval(d) *= 10.;
}
}
else {
#endif
/* Generate ilim digits, then fix them up. */
dval(eps) *= tens[ilim-1];
for(i = 1;; i++, dval(d) *= 10.) {
if ( (L = (Long)(dval(d)/ds)) !=0)
dval(d) -= L*ds;
*s++ = '0' + (int)L;
if (i == ilim) {
ds *= 0.5;
if (dval(d) > ds + dval(eps))
goto bump_up;
else if (dval(d) < ds - dval(eps)) {
while(*--s == '0'){}
s++;
if (dval(d))
inex = STRTOG_Inexlo;
goto ret1;
}
break;
}
}
#ifndef No_leftright
}
#endif
fast_failed:
s = s0;
dval(d) = d2;
k = k0;
ilim = ilim0;
}
/* Do we have a "small" integer? */
if (be >= 0 && k <= Int_max) {
/* Yes. */
ds = tens[k];
if (ndigits < 0 && ilim <= 0) {
S = mhi = 0;
if (ilim < 0 || dval(d) <= 5*ds)
goto no_digits;
goto one_digit;
}
for(i = 1;; i++, dval(d) *= 10.) {
L = (Long)(dval(d) / ds);
dval(d) -= L*ds;
#ifdef Check_FLT_ROUNDS
/* If FLT_ROUNDS == 2, L will usually be high by 1 */
if (dval(d) < 0) {
L--;
dval(d) += ds;
}
#endif
*s++ = '0' + (int)L;
if (dval(d) == 0.)
break;
if (i == ilim) {
if (rdir) {
if (rdir == 1)
goto bump_up;
inex = STRTOG_Inexlo;
goto ret1;
}
dval(d) += dval(d);
if (dval(d) > ds || dval(d) == ds && L & 1) {
bump_up:
inex = STRTOG_Inexhi;
while(*--s == '9')
if (s == s0) {
k++;
*s = '0';
break;
}
++*s++;
}
else
inex = STRTOG_Inexlo;
break;
}
}
goto ret1;
}
m2 = b2;
m5 = b5;
mhi = mlo = 0;
if (leftright) {
if (mode < 2) {
i = nbits - bbits;
if (be - i++ < fpi->emin)
/* denormal */
i = be - fpi->emin + 1;
}
else {
j = ilim - 1;
if (m5 >= j)
m5 -= j;
else {
s5 += j -= m5;
b5 += j;
m5 = 0;
}
if ((i = ilim) < 0) {
m2 -= i;
i = 0;
}
}
b2 += i;
s2 += i;
mhi = i2b(1);
}
if (m2 > 0 && s2 > 0) {
i = m2 < s2 ? m2 : s2;
b2 -= i;
m2 -= i;
s2 -= i;
}
if (b5 > 0) {
if (leftright) {
if (m5 > 0) {
mhi = pow5mult(mhi, m5);
b1 = mult(mhi, b);
Bfree(b);
b = b1;
}
if ( (j = b5 - m5) !=0)
b = pow5mult(b, j);
}
else
b = pow5mult(b, b5);
}
S = i2b(1);
if (s5 > 0)
S = pow5mult(S, s5);
/* Check for special case that d is a normalized power of 2. */
spec_case = 0;
if (mode < 2) {
if (bbits == 1 && be0 > fpi->emin + 1) {
/* The special case */
b2++;
s2++;
spec_case = 1;
}
}
/* Arrange for convenient computation of quotients:
* shift left if necessary so divisor has 4 leading 0 bits.
*
* Perhaps we should just compute leading 28 bits of S once
* and for all and pass them and a shift to quorem, so it
* can do shifts and ors to compute the numerator for q.
*/
#ifdef Pack_32
if ( (i = ((s5 ? 32 - hi0bits(S->x[S->wds-1]) : 1) + s2) & 0x1f) !=0)
i = 32 - i;
#else
if ( (i = ((s5 ? 32 - hi0bits(S->x[S->wds-1]) : 1) + s2) & 0xf) !=0)
i = 16 - i;
#endif
if (i > 4) {
i -= 4;
b2 += i;
m2 += i;
s2 += i;
}
else if (i < 4) {
i += 28;
b2 += i;
m2 += i;
s2 += i;
}
if (b2 > 0)
b = lshift(b, b2);
if (s2 > 0)
S = lshift(S, s2);
if (k_check) {
if (cmp(b,S) < 0) {
k--;
b = multadd(b, 10, 0); /* we botched the k estimate */
if (leftright)
mhi = multadd(mhi, 10, 0);
ilim = ilim1;
}
}
if (ilim <= 0 && mode > 2) {
if (ilim < 0 || cmp(b,S = multadd(S,5,0)) <= 0) {
/* no digits, fcvt style */
no_digits:
k = -1 - ndigits;
inex = STRTOG_Inexlo;
goto ret;
}
one_digit:
inex = STRTOG_Inexhi;
*s++ = '1';
k++;
goto ret;
}
if (leftright) {
if (m2 > 0)
mhi = lshift(mhi, m2);
/* Compute mlo -- check for special case
* that d is a normalized power of 2.
*/
mlo = mhi;
if (spec_case) {
mhi = Balloc(mhi->k);
Bcopy(mhi, mlo);
mhi = lshift(mhi, 1);
}
for(i = 1;;i++) {
dig = quorem(b,S) + '0';
/* Do we yet have the shortest decimal string
* that will round to d?
*/
j = cmp(b, mlo);
delta = diff(S, mhi);
j1 = delta->sign ? 1 : cmp(b, delta);
Bfree(delta);
#ifndef ROUND_BIASED
if (j1 == 0 && !mode && !(bits[0] & 1) && !rdir) {
if (dig == '9')
goto round_9_up;
if (j <= 0) {
if (b->wds > 1 || b->x[0])
inex = STRTOG_Inexlo;
}
else {
dig++;
inex = STRTOG_Inexhi;
}
*s++ = dig;
goto ret;
}
#endif
if (j < 0 || j == 0 && !mode
#ifndef ROUND_BIASED
&& !(bits[0] & 1)
#endif
) {
if (rdir && (b->wds > 1 || b->x[0])) {
if (rdir == 2) {
inex = STRTOG_Inexlo;
goto accept;
}
while (cmp(S,mhi) > 0) {
*s++ = dig;
mhi1 = multadd(mhi, 10, 0);
if (mlo == mhi)
mlo = mhi1;
mhi = mhi1;
b = multadd(b, 10, 0);
dig = quorem(b,S) + '0';
}
if (dig++ == '9')
goto round_9_up;
inex = STRTOG_Inexhi;
goto accept;
}
if (j1 > 0) {
b = lshift(b, 1);
j1 = cmp(b, S);
if ((j1 > 0 || j1 == 0 && dig & 1)
&& dig++ == '9')
goto round_9_up;
inex = STRTOG_Inexhi;
}
if (b->wds > 1 || b->x[0])
inex = STRTOG_Inexlo;
accept:
*s++ = dig;
goto ret;
}
if (j1 > 0 && rdir != 2) {
if (dig == '9') { /* possible if i == 1 */
round_9_up:
*s++ = '9';
inex = STRTOG_Inexhi;
goto roundoff;
}
inex = STRTOG_Inexhi;
*s++ = dig + 1;
goto ret;
}
*s++ = dig;
if (i == ilim)
break;
b = multadd(b, 10, 0);
if (mlo == mhi)
mlo = mhi = multadd(mhi, 10, 0);
else {
mlo = multadd(mlo, 10, 0);
mhi = multadd(mhi, 10, 0);
}
}
}
else
for(i = 1;; i++) {
*s++ = dig = quorem(b,S) + '0';
if (i >= ilim)
break;
b = multadd(b, 10, 0);
}
/* Round off last digit */
if (rdir) {
if (rdir == 2 || b->wds <= 1 && !b->x[0])
goto chopzeros;
goto roundoff;
}
b = lshift(b, 1);
j = cmp(b, S);
if (j > 0 || j == 0 && dig & 1) {
roundoff:
inex = STRTOG_Inexhi;
while(*--s == '9')
if (s == s0) {
k++;
*s++ = '1';
goto ret;
}
++*s++;
}
else {
chopzeros:
if (b->wds > 1 || b->x[0])
inex = STRTOG_Inexlo;
while(*--s == '0'){}
s++;
}
ret:
Bfree(S);
if (mhi) {
if (mlo && mlo != mhi)
Bfree(mlo);
Bfree(mhi);
}
ret1:
Bfree(b);
*s = 0;
*decpt = k + 1;
if (rve)
*rve = s;
*kindp |= inex;
return s0;
}