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/smisc.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/smisc.c')
-rw-r--r-- | contrib/gdtoa/smisc.c | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/contrib/gdtoa/smisc.c b/contrib/gdtoa/smisc.c new file mode 100644 index 0000000..e20e9da --- /dev/null +++ b/contrib/gdtoa/smisc.c @@ -0,0 +1,197 @@ +/**************************************************************** + +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 + Bell Laboratories, Room 2C-463 + 600 Mountain Avenue + Murray Hill, NJ 07974-0636 + U.S.A. + dmg@bell-labs.com + */ + +#include "gdtoaimp.h" + + Bigint * +s2b +#ifdef KR_headers + (s, nd0, nd, y9) CONST char *s; int nd0, nd; ULong y9; +#else + (CONST char *s, int nd0, int nd, ULong y9) +#endif +{ + Bigint *b; + int i, k; + Long x, y; + + x = (nd + 8) / 9; + for(k = 0, y = 1; x > y; y <<= 1, k++) ; +#ifdef Pack_32 + b = Balloc(k); + b->x[0] = y9; + b->wds = 1; +#else + b = Balloc(k+1); + b->x[0] = y9 & 0xffff; + b->wds = (b->x[1] = y9 >> 16) ? 2 : 1; +#endif + + i = 9; + if (9 < nd0) { + s += 9; + do b = multadd(b, 10, *s++ - '0'); + while(++i < nd0); + s++; + } + else + s += 10; + for(; i < nd; i++) + b = multadd(b, 10, *s++ - '0'); + return b; + } + + double +ratio +#ifdef KR_headers + (a, b) Bigint *a, *b; +#else + (Bigint *a, Bigint *b) +#endif +{ + double da, db; + int k, ka, kb; + + dval(da) = b2d(a, &ka); + dval(db) = b2d(b, &kb); + k = ka - kb + ULbits*(a->wds - b->wds); +#ifdef IBM + if (k > 0) { + word0(da) += (k >> 2)*Exp_msk1; + if (k &= 3) + dval(da) *= 1 << k; + } + else { + k = -k; + word0(db) += (k >> 2)*Exp_msk1; + if (k &= 3) + dval(db) *= 1 << k; + } +#else + if (k > 0) + word0(da) += k*Exp_msk1; + else { + k = -k; + word0(db) += k*Exp_msk1; + } +#endif + return dval(da) / dval(db); + } + +#ifdef INFNAN_CHECK + + int +match +#ifdef KR_headers + (sp, t) char **sp, *t; +#else + (CONST char **sp, char *t) +#endif +{ + int c, d; + CONST char *s = *sp; + + while( (d = *t++) !=0) { + if ((c = *++s) >= 'A' && c <= 'Z') + c += 'a' - 'A'; + if (c != d) + return 0; + } + *sp = s + 1; + return 1; + } +#endif /* INFNAN_CHECK */ + + void +#ifdef KR_headers +copybits(c, n, b) ULong *c; int n; Bigint *b; +#else +copybits(ULong *c, int n, Bigint *b) +#endif +{ + ULong *ce, *x, *xe; +#ifdef Pack_16 + int nw, nw1; +#endif + + ce = c + ((n-1) >> kshift) + 1; + x = b->x; +#ifdef Pack_32 + xe = x + b->wds; + while(x < xe) + *c++ = *x++; +#else + nw = b->wds; + nw1 = nw & 1; + for(xe = x + (nw - nw1); x < xe; x += 2) + Storeinc(c, x[1], x[0]); + if (nw1) + *c++ = *x; +#endif + while(c < ce) + *c++ = 0; + } + + ULong +#ifdef KR_headers +any_on(b, k) Bigint *b; int k; +#else +any_on(Bigint *b, int k) +#endif +{ + int n, nwds; + ULong *x, *x0, x1, x2; + + x = b->x; + nwds = b->wds; + n = k >> kshift; + if (n > nwds) + n = nwds; + else if (n < nwds && (k &= kmask)) { + x1 = x2 = x[n]; + x1 >>= k; + x1 <<= k; + if (x1 != x2) + return 1; + } + x0 = x; + x += n; + while(x > x0) + if (*--x) + return 1; + return 0; + } |