diff options
author | das <das@FreeBSD.org> | 2003-03-12 20:18:32 +0000 |
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committer | das <das@FreeBSD.org> | 2003-03-12 20:18:32 +0000 |
commit | db3a0f1435efcb4461005cb8d8509bff01f9b018 (patch) | |
tree | 632bc138392cfc4c37a7e12065afe443d31145eb /contrib/gdtoa/dmisc.c | |
download | FreeBSD-src-db3a0f1435efcb4461005cb8d8509bff01f9b018.zip FreeBSD-src-db3a0f1435efcb4461005cb8d8509bff01f9b018.tar.gz |
Initial import of David Gay's gdtoa library for conversion between
strings and floating point.
Diffstat (limited to 'contrib/gdtoa/dmisc.c')
-rw-r--r-- | contrib/gdtoa/dmisc.c | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/contrib/gdtoa/dmisc.c b/contrib/gdtoa/dmisc.c new file mode 100644 index 0000000..14b5d7e --- /dev/null +++ b/contrib/gdtoa/dmisc.c @@ -0,0 +1,222 @@ +/**************************************************************** + +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 + Bell Laboratories, Room 2C-463 + 600 Mountain Avenue + Murray Hill, NJ 07974-0636 + U.S.A. + dmg@bell-labs.com + */ + +#include "gdtoaimp.h" + +#ifndef MULTIPLE_THREADS + char *dtoa_result; +#endif + + char * +#ifdef KR_headers +rv_alloc(i) int i; +#else +rv_alloc(int i) +#endif +{ + int j, k, *r; + + j = sizeof(ULong); + for(k = 0; + sizeof(Bigint) - sizeof(ULong) - sizeof(int) + j <= i; + j <<= 1) + k++; + r = (int*)Balloc(k); + *r = k; + return +#ifndef MULTIPLE_THREADS + dtoa_result = +#endif + (char *)(r+1); + } + + char * +#ifdef KR_headers +nrv_alloc(s, rve, n) char *s, **rve; int n; +#else +nrv_alloc(char *s, char **rve, int n) +#endif +{ + char *rv, *t; + + t = rv = rv_alloc(n); + while((*t = *s++) !=0) + t++; + if (rve) + *rve = t; + return rv; + } + +/* freedtoa(s) must be used to free values s returned by dtoa + * when MULTIPLE_THREADS is #defined. It should be used in all cases, + * but for consistency with earlier versions of dtoa, it is optional + * when MULTIPLE_THREADS is not defined. + */ + + void +#ifdef KR_headers +freedtoa(s) char *s; +#else +freedtoa(char *s) +#endif +{ + Bigint *b = (Bigint *)((int *)s - 1); + b->maxwds = 1 << (b->k = *(int*)b); + Bfree(b); +#ifndef MULTIPLE_THREADS + if (s == dtoa_result) + dtoa_result = 0; +#endif + } + + int +quorem +#ifdef KR_headers + (b, S) Bigint *b, *S; +#else + (Bigint *b, Bigint *S) +#endif +{ + int n; + ULong *bx, *bxe, q, *sx, *sxe; +#ifdef ULLong + ULLong borrow, carry, y, ys; +#else + ULong borrow, carry, y, ys; +#ifdef Pack_32 + ULong si, z, zs; +#endif +#endif + + n = S->wds; +#ifdef DEBUG + /*debug*/ if (b->wds > n) + /*debug*/ Bug("oversize b in quorem"); +#endif + if (b->wds < n) + return 0; + sx = S->x; + sxe = sx + --n; + bx = b->x; + bxe = bx + n; + q = *bxe / (*sxe + 1); /* ensure q <= true quotient */ +#ifdef DEBUG + /*debug*/ if (q > 9) + /*debug*/ Bug("oversized quotient in quorem"); +#endif + if (q) { + borrow = 0; + carry = 0; + do { +#ifdef ULLong + ys = *sx++ * (ULLong)q + carry; + carry = ys >> 32; + y = *bx - (ys & 0xffffffffUL) - borrow; + borrow = y >> 32 & 1UL; + *bx++ = y & 0xffffffffUL; +#else +#ifdef Pack_32 + si = *sx++; + ys = (si & 0xffff) * q + carry; + zs = (si >> 16) * q + (ys >> 16); + carry = zs >> 16; + y = (*bx & 0xffff) - (ys & 0xffff) - borrow; + borrow = (y & 0x10000) >> 16; + z = (*bx >> 16) - (zs & 0xffff) - borrow; + borrow = (z & 0x10000) >> 16; + Storeinc(bx, z, y); +#else + ys = *sx++ * q + carry; + carry = ys >> 16; + y = *bx - (ys & 0xffff) - borrow; + borrow = (y & 0x10000) >> 16; + *bx++ = y & 0xffff; +#endif +#endif + } + while(sx <= sxe); + if (!*bxe) { + bx = b->x; + while(--bxe > bx && !*bxe) + --n; + b->wds = n; + } + } + if (cmp(b, S) >= 0) { + q++; + borrow = 0; + carry = 0; + bx = b->x; + sx = S->x; + do { +#ifdef ULLong + ys = *sx++ + carry; + carry = ys >> 32; + y = *bx - (ys & 0xffffffffUL) - borrow; + borrow = y >> 32 & 1UL; + *bx++ = y & 0xffffffffUL; +#else +#ifdef Pack_32 + si = *sx++; + ys = (si & 0xffff) + carry; + zs = (si >> 16) + (ys >> 16); + carry = zs >> 16; + y = (*bx & 0xffff) - (ys & 0xffff) - borrow; + borrow = (y & 0x10000) >> 16; + z = (*bx >> 16) - (zs & 0xffff) - borrow; + borrow = (z & 0x10000) >> 16; + Storeinc(bx, z, y); +#else + ys = *sx++ + carry; + carry = ys >> 16; + y = *bx - (ys & 0xffff) - borrow; + borrow = (y & 0x10000) >> 16; + *bx++ = y & 0xffff; +#endif +#endif + } + while(sx <= sxe); + bx = b->x; + bxe = bx + n; + if (!*bxe) { + while(--bxe > bx && !*bxe) + --n; + b->wds = n; + } + } + return q; + } |