diff options
Diffstat (limited to 'newlib/libc/stdlib/gdtoa-gethex.c')
-rw-r--r-- | newlib/libc/stdlib/gdtoa-gethex.c | 351 |
1 files changed, 351 insertions, 0 deletions
diff --git a/newlib/libc/stdlib/gdtoa-gethex.c b/newlib/libc/stdlib/gdtoa-gethex.c new file mode 100644 index 0000000..92f30fc --- /dev/null +++ b/newlib/libc/stdlib/gdtoa-gethex.c @@ -0,0 +1,351 @@ +/**************************************************************** + +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 "."). */ + +#include <_ansi.h> +#include <reent.h> +#include <string.h> +#include "mprec.h" +#include "gdtoa.h" +#include "gd_qnan.h" + +#ifdef USE_LOCALE +#include "locale.h" +#endif + +unsigned char hexdig[256]; + +static void +_DEFUN (htinit, (h, s, inc), + unsigned char *h _AND + unsigned char *s _AND + int inc) +{ + int i, j; + for(i = 0; (j = s[i]) !=0; i++) + h[j] = i + inc; +} + +void +_DEFUN_VOID (hexdig_init) +{ +#define USC (unsigned char *) + htinit(hexdig, USC "0123456789", 0x10); + htinit(hexdig, USC "abcdef", 0x10 + 10); + htinit(hexdig, USC "ABCDEF", 0x10 + 10); +} + +static void +_DEFUN(rshift, (b, k), + _Bigint *b _AND + int k) +{ + __ULong *x, *x1, *xe, y; + int n; + + x = x1 = b->_x; + n = k >> kshift; + if (n < b->_wds) { + xe = x + b->_wds; + x += n; + if (k &= kmask) { + n = ULbits - k; + y = *x++ >> k; + while(x < xe) { + *x1++ = (y | (*x << n)) & ALL_ON; + y = *x++ >> k; + } + if ((*x1 = y) !=0) + x1++; + } + else + while(x < xe) + *x1++ = *x++; + } + if ((b->_wds = x1 - b->_x) == 0) + b->_x[0] = 0; +} + +static _Bigint * +_DEFUN (increment, (ptr, b), + struct _reent *ptr _AND + _Bigint *b) +{ + __ULong *x, *xe; + _Bigint *b1; +#ifdef Pack_16 + __ULong carry = 1, y; +#endif + + x = b->_x; + xe = x + b->_wds; +#ifdef Pack_32 + do { + if (*x < (__ULong)0xffffffffL) { + ++*x; + return b; + } + *x++ = 0; + } while(x < xe); +#else + do { + y = *x + carry; + carry = y >> 16; + *x++ = y & 0xffff; + if (!carry) + return b; + } while(x < xe); + if (carry) +#endif + { + if (b->_wds >= b->_maxwds) { + b1 = Balloc(ptr, b->_k+1); + Bcopy(b1, b); + Bfree(ptr, b); + b = b1; + } + b->_x[b->_wds++] = 1; + } + return b; +} + + +int +_DEFUN(gethex, (ptr, sp, fpi, exp, bp, sign), + struct _reent *ptr _AND + _CONST char **sp _AND + FPI *fpi _AND + Long *exp _AND + _Bigint **bp _AND + int sign) +{ + _Bigint *b; + _CONST unsigned char *decpt, *s0, *s, *s1; + int esign, havedig, irv, k, n, nbits, up, zret; + __ULong L, lostbits, *x; + Long e, e1; +#ifdef USE_LOCALE + unsigned char decimalpoint = *localeconv()->decimal_point; +#else +#define decimalpoint '.' +#endif + + if (!hexdig['0']) + hexdig_init(); + havedig = 0; + s0 = *(_CONST unsigned char **)sp + 2; + while(s0[havedig] == '0') + havedig++; + s0 += havedig; + s = s0; + decpt = 0; + zret = 0; + e = 0; + if (!hexdig[*s]) { + zret = 1; + if (*s != decimalpoint) + goto pcheck; + decpt = ++s; + if (!hexdig[*s]) + goto pcheck; + while(*s == '0') + s++; + if (hexdig[*s]) + zret = 0; + havedig = 1; + s0 = s; + } + while(hexdig[*s]) + s++; + if (*s == decimalpoint && !decpt) { + decpt = ++s; + while(hexdig[*s]) + s++; + } + if (decpt) + e = -(((Long)(s-decpt)) << 2); + pcheck: + s1 = s; + switch(*s) { + case 'p': + case 'P': + esign = 0; + switch(*++s) { + case '-': + esign = 1; + /* no break */ + case '+': + s++; + } + if ((n = hexdig[*s]) == 0 || n > 0x19) { + s = s1; + break; + } + e1 = n - 0x10; + while((n = hexdig[*++s]) !=0 && n <= 0x19) + e1 = 10*e1 + n - 0x10; + if (esign) + e1 = -e1; + e += e1; + } + *sp = (char*)s; + if (zret) + return havedig ? STRTOG_Zero : STRTOG_NoNumber; + n = s1 - s0 - 1; + for(k = 0; n > 7; n >>= 1) + k++; + b = Balloc(ptr, k); + x = b->_x; + n = 0; + L = 0; + while(s1 > s0) { + if (*--s1 == decimalpoint) + continue; + if (n == 32) { + *x++ = L; + L = 0; + n = 0; + } + L |= (hexdig[*s1] & 0x0f) << n; + n += 4; + } + *x++ = L; + b->_wds = n = x - b->_x; + n = 32*n - hi0bits(L); + nbits = fpi->nbits; + lostbits = 0; + x = b->_x; + if (n > nbits) { + n -= nbits; + if (any_on(b,n)) { + lostbits = 1; + k = n - 1; + if (x[k>>kshift] & 1 << (k & kmask)) { + lostbits = 2; + if (k > 1 && any_on(b,k-1)) + lostbits = 3; + } + } + rshift(b, n); + e += n; + } + else if (n < nbits) { + n = nbits - n; + b = lshift(ptr, b, n); + e -= n; + x = b->_x; + } + if (e > fpi->emax) { + ovfl: + Bfree(ptr, b); + *bp = 0; + 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: + if (n == nbits && (n < 2 || any_on(b,n-1))) + goto one_bit; + break; + case FPI_Round_up: + if (!sign) + goto one_bit; + break; + case FPI_Round_down: + if (sign) { + one_bit: + *exp = fpi->emin; + x[0] = b->_wds = 1; + *bp = b; + return STRTOG_Denormal | STRTOG_Inexhi + | STRTOG_Underflow; + } + } + Bfree(ptr, b); + *bp = 0; + return STRTOG_Zero | STRTOG_Inexlo | STRTOG_Underflow; + } + k = n - 1; + if (lostbits) + lostbits = 1; + else if (k > 0) + lostbits = any_on(b,k); + if (x[k>>kshift] & 1 << (k & kmask)) + lostbits |= 2; + nbits -= n; + rshift(b,n); + e = fpi->emin; + } + if (lostbits) { + up = 0; + switch(fpi->rounding) { + case FPI_Round_zero: + break; + case FPI_Round_near: + if ((lostbits & 2) + && ((lostbits & 1) | (x[0] & 1))) + up = 1; + break; + case FPI_Round_up: + up = 1 - sign; + break; + case FPI_Round_down: + up = sign; + } + if (up) { + k = b->_wds; + b = increment(ptr, b); + x = b->_x; + if (irv == STRTOG_Denormal) { + if (nbits == fpi->nbits - 1 + && x[nbits >> kshift] & 1 << (nbits & kmask)) + irv = STRTOG_Normal; + } + else if ((b->_wds > k) + || ((n = nbits & kmask) !=0 + && (hi0bits(x[k-1]) < 32-n))) { + rshift(b,1); + if (++e > fpi->emax) + goto ovfl; + } + irv |= STRTOG_Inexhi; + } + else + irv |= STRTOG_Inexlo; + } + *bp = b; + *exp = e; + return irv; +} + |