Clean up gdtoa code

This commit is contained in:
Justine Tunney 2021-08-19 06:07:37 -07:00
parent 7341336b1a
commit da45c7c80b
48 changed files with 2808 additions and 4721 deletions

View file

@ -1,68 +1,50 @@
/*-*- mode:c;indent-tabs-mode:t;c-basic-offset:8;tab-width:8;coding:utf-8 -*-│
vi: set et ft=c ts=8 tw=8 fenc=utf-8 :vi
The author of this software is David M. Gay.
Please send bug reports to David M. Gay <dmg@acm.org>
or Justine Tunney <jtunney@gmail.com>
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.
*/
#include "libc/errno.h"
#include "third_party/gdtoa/gdtoa.internal.h"
/* clang-format off */
/****************************************************************
The author of this software is David M. Gay.
Copyright (C) 1998 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 "."). */
int
gethex( CONST char **sp, CONST FPI *fpi, Long *exp, Bigint **bp, int sign MTd)
gethex( const char **sp, const FPI *fpi, Long *exp, Bigint **bp, int sign)
{
Bigint *b;
CONST unsigned char *decpt, *s0, *s, *s1;
const unsigned char *decpt, *s0, *s, *s1;
int big, esign, havedig, irv, j, k, n, n0, nbits, up, zret;
ULong L, lostbits, *x;
Long e, e1;
#ifdef USE_LOCALE
int i;
#ifdef NO_LOCALE_CACHE
const unsigned char *decimalpoint = (unsigned char*)localeconv()->decimal_point;
#else
const unsigned char *decimalpoint;
static unsigned char *decimalpoint_cache;
if (!(s0 = decimalpoint_cache)) {
s0 = (unsigned char*)localeconv()->decimal_point;
if ((decimalpoint_cache = (char*)MALLOC(strlen(s0) + 1))) {
strcpy(decimalpoint_cache, s0);
s0 = decimalpoint_cache;
}
}
decimalpoint = s0;
#endif
#endif
/**** if (!hexdig['0']) __gdtoa_hexdig_init(); ****/
*bp = 0;
havedig = 0;
s0 = *(CONST unsigned char **)sp + 2;
s0 = *(const unsigned char **)sp + 2;
while(s0[havedig] == '0')
havedig++;
s0 += havedig;
@ -74,17 +56,9 @@ gethex( CONST char **sp, CONST FPI *fpi, Long *exp, Bigint **bp, int sign MTd)
havedig++;
else {
zret = 1;
#ifdef USE_LOCALE
for(i = 0; decimalpoint[i]; ++i) {
if (s[i] != decimalpoint[i])
goto pcheck;
}
decpt = s += i;
#else
if (*s != '.')
goto pcheck;
decpt = ++s;
#endif
if (!hexdig[*s])
goto pcheck;
while(*s == '0')
@ -93,52 +67,43 @@ gethex( CONST char **sp, CONST FPI *fpi, Long *exp, Bigint **bp, int sign MTd)
zret = 0;
havedig = 1;
s0 = s;
}
}
while(hexdig[*s])
s++;
#ifdef USE_LOCALE
if (*s == *decimalpoint && !decpt) {
for(i = 1; decimalpoint[i]; ++i) {
if (s[i] != decimalpoint[i])
goto pcheck;
}
decpt = s += i;
#else
if (*s == '.' && !decpt) {
decpt = ++s;
#endif
while(hexdig[*s])
s++;
}/*}*/
}/*}*/
if (decpt)
e = -(((Long)(s-decpt)) << 2);
pcheck:
pcheck:
s1 = s;
big = esign = 0;
switch(*s) {
case 'p':
case 'P':
case 'p':
case 'P':
switch(*++s) {
case '-':
case '-':
esign = 1;
/* no break */
case '+':
case '+':
s++;
}
}
if ((n = hexdig[*s]) == 0 || n > 0x19) {
s = s1;
break;
}
}
e1 = n - 0x10;
while((n = hexdig[*++s]) !=0 && n <= 0x19) {
if (e1 & 0xf8000000)
big = 1;
e1 = 10*e1 + n - 0x10;
}
}
if (esign)
e1 = -e1;
e += e1;
}
}
*sp = (char*)s;
if (!havedig)
*sp = (char*)s0 - 1;
@ -147,40 +112,40 @@ gethex( CONST char **sp, CONST FPI *fpi, Long *exp, Bigint **bp, int sign MTd)
if (big) {
if (esign) {
switch(fpi->rounding) {
case FPI_Round_up:
case FPI_Round_up:
if (sign)
break;
goto ret_tiny;
case FPI_Round_down:
case FPI_Round_down:
if (!sign)
break;
goto ret_tiny;
}
}
goto retz;
ret_tiny:
b = Balloc(0 MTa);
ret_tiny:
b = Balloc(0);
b->wds = 1;
b->x[0] = 1;
goto dret;
}
}
switch(fpi->rounding) {
case FPI_Round_near:
case FPI_Round_near:
goto ovfl1;
case FPI_Round_up:
case FPI_Round_up:
if (!sign)
goto ovfl1;
goto ret_big;
case FPI_Round_down:
case FPI_Round_down:
if (sign)
goto ovfl1;
}
ret_big:
}
ret_big:
nbits = fpi->nbits;
n0 = n = nbits >> kshift;
if (nbits & kmask)
++n;
for(j = n, k = 0; j >>= 1; ++k);
*bp = b = Balloc(k MTa);
*bp = b = Balloc(k);
b->wds = n;
for(j = 0; j < n0; ++j)
b->x[j] = ALL_ON;
@ -188,35 +153,25 @@ gethex( CONST char **sp, CONST FPI *fpi, Long *exp, Bigint **bp, int sign MTd)
b->x[j] = ALL_ON >> (ULbits - (nbits & kmask));
*exp = fpi->emax;
return STRTOG_Normal | STRTOG_Inexlo;
}
}
n = s1 - s0 - 1;
for(k = 0; n > (1 << (kshift-2)) - 1; n >>= 1)
k++;
b = Balloc(k MTa);
b = Balloc(k);
x = b->x;
n = 0;
L = 0;
#ifdef USE_LOCALE
for(i = 0; decimalpoint[i+1]; ++i);
#endif
while(s1 > s0) {
#ifdef USE_LOCALE
if (*--s1 == decimalpoint[i]) {
s1 -= i;
continue;
}
#else
if (*--s1 == '.')
continue;
#endif
if (n == ULbits) {
*x++ = L;
L = 0;
n = 0;
}
}
L |= (hexdig[*s1] & 0x0f) << n;
n += 4;
}
}
*x++ = L;
b->wds = n = x - b->x;
n = ULbits*n - hi0bits(L);
@ -232,72 +187,66 @@ gethex( CONST char **sp, CONST FPI *fpi, Long *exp, Bigint **bp, int sign MTd)
lostbits = 2;
if (k > 0 && any_on(b,k))
lostbits = 3;
}
}
}
rshift(b, n);
e += n;
}
}
else if (n < nbits) {
n = nbits - n;
b = lshift(b, n MTa);
b = lshift(b, n);
e -= n;
x = b->x;
}
}
if (e > fpi->emax) {
ovfl:
Bfree(b MTa);
ovfl1:
#ifndef NO_ERRNO
ovfl:
Bfree(b);
ovfl1:
errno = ERANGE;
#endif
switch (fpi->rounding) {
case FPI_Round_zero:
case FPI_Round_zero:
goto ret_big;
case FPI_Round_down:
case FPI_Round_down:
if (!sign)
goto ret_big;
break;
case FPI_Round_up:
case FPI_Round_up:
if (sign)
goto ret_big;
}
return STRTOG_Infinite | STRTOG_Overflow | STRTOG_Inexhi;
}
return STRTOG_Infinite | STRTOG_Overflow | STRTOG_Inexhi;
}
irv = STRTOG_Normal;
if (e < fpi->emin) {
irv = STRTOG_Denormal;
n = fpi->emin - e;
if (n >= nbits) {
switch (fpi->rounding) {
case FPI_Round_near:
case FPI_Round_near:
if (n == nbits && (n < 2 || lostbits || any_on(b,n-1)))
goto one_bit;
break;
case FPI_Round_up:
case FPI_Round_up:
if (!sign)
goto one_bit;
break;
case FPI_Round_down:
case FPI_Round_down:
if (sign) {
one_bit:
one_bit:
x[0] = b->wds = 1;
dret:
dret:
*bp = b;
*exp = fpi->emin;
#ifndef NO_ERRNO
errno = ERANGE;
#endif
return STRTOG_Denormal | STRTOG_Inexhi
| STRTOG_Underflow;
}
}
Bfree(b MTa);
retz:
#ifndef NO_ERRNO
errno = ERANGE;
#endif
return STRTOG_Zero | STRTOG_Inexlo | STRTOG_Underflow;
}
}
Bfree(b);
retz:
errno = ERANGE;
return STRTOG_Zero | STRTOG_Inexlo | STRTOG_Underflow;
}
k = n - 1;
if (lostbits)
lostbits = 1;
@ -308,45 +257,45 @@ gethex( CONST char **sp, CONST FPI *fpi, Long *exp, Bigint **bp, int sign MTd)
nbits -= n;
rshift(b,n);
e = fpi->emin;
}
}
if (lostbits) {
up = 0;
switch(fpi->rounding) {
case FPI_Round_zero:
case FPI_Round_zero:
break;
case FPI_Round_near:
case FPI_Round_near:
if (lostbits & 2
&& (lostbits | x[0]) & 1)
&& (lostbits | x[0]) & 1)
up = 1;
break;
case FPI_Round_up:
case FPI_Round_up:
up = 1 - sign;
break;
case FPI_Round_down:
case FPI_Round_down:
up = sign;
}
}
if (up) {
k = b->wds;
b = increment(b MTa);
b = increment(b);
x = b->x;
if (irv == STRTOG_Denormal) {
if (nbits == fpi->nbits - 1
&& x[nbits >> kshift] & 1 << (nbits & kmask))
&& x[nbits >> kshift] & 1 << (nbits & kmask))
irv = STRTOG_Normal;
}
}
else if (b->wds > k
|| ((n = nbits & kmask) !=0
&& hi0bits(x[k-1]) < 32-n)) {
|| ((n = nbits & kmask) !=0
&& hi0bits(x[k-1]) < 32-n)) {
rshift(b,1);
if (++e > fpi->emax)
goto ovfl;
}
irv |= STRTOG_Inexhi;
}
irv |= STRTOG_Inexhi;
}
else
irv |= STRTOG_Inexlo;
}
}
*bp = b;
*exp = e;
return irv;
}
}