projects / apple / libc.git / blame
| Commit | Line | Data |
|---|---|---|
| 9385eb3d A |
1 | /**************************************************************** |
| 2 | ||
| 3 | The author of this software is David M. Gay. | |
| 4 | ||
| 5 | Copyright (C) 1998 by Lucent Technologies | |
| 6 | All Rights Reserved | |
| 7 | ||
| 8 | Permission to use, copy, modify, and distribute this software and | |
| 9 | its documentation for any purpose and without fee is hereby | |
| 10 | granted, provided that the above copyright notice appear in all | |
| 11 | copies and that both that the copyright notice and this | |
| 12 | permission notice and warranty disclaimer appear in supporting | |
| 13 | documentation, and that the name of Lucent or any of its entities | |
| 14 | not be used in advertising or publicity pertaining to | |
| 15 | distribution of the software without specific, written prior | |
| 16 | permission. | |
| 17 | ||
| 18 | LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, | |
| 19 | INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. | |
| 20 | IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY | |
| 21 | SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES | |
| 22 | WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER | |
| 23 | IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, | |
| 24 | ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF | |
| 25 | THIS SOFTWARE. | |
| 26 | ||
| 27 | ****************************************************************/ | |
| 28 | ||
| 3d9156a7 A |
29 | /* Please send bug reports to David M. Gay (dmg at acm dot org, |
| 30 | * with " at " changed at "@" and " dot " changed to "."). */ | |
| 9385eb3d A |
31 | |
| 32 | #include "gdtoaimp.h" | |
| 33 | ||
| 34 | Bigint * | |
| 35 | #ifdef KR_headers | |
| 36 | sum(a, b) Bigint *a; Bigint *b; | |
| 37 | #else | |
| 38 | sum(Bigint *a, Bigint *b) | |
| 39 | #endif | |
| 40 | { | |
| 41 | Bigint *c; | |
| 42 | ULong carry, *xc, *xa, *xb, *xe, y; | |
| 43 | #ifdef Pack_32 | |
| 44 | ULong z; | |
| 45 | #endif | |
| 46 | ||
| 47 | if (a->wds < b->wds) { | |
| 48 | c = b; b = a; a = c; | |
| 49 | } | |
| 50 | c = Balloc(a->k); | |
| 51 | c->wds = a->wds; | |
| 52 | carry = 0; | |
| 53 | xa = a->x; | |
| 54 | xb = b->x; | |
| 55 | xc = c->x; | |
| 56 | xe = xc + b->wds; | |
| 57 | #ifdef Pack_32 | |
| 58 | do { | |
| 59 | y = (*xa & 0xffff) + (*xb & 0xffff) + carry; | |
| 60 | carry = (y & 0x10000) >> 16; | |
| 61 | z = (*xa++ >> 16) + (*xb++ >> 16) + carry; | |
| 62 | carry = (z & 0x10000) >> 16; | |
| 63 | Storeinc(xc, z, y); | |
| 64 | } | |
| 65 | while(xc < xe); | |
| 66 | xe += a->wds - b->wds; | |
| 67 | while(xc < xe) { | |
| 68 | y = (*xa & 0xffff) + carry; | |
| 69 | carry = (y & 0x10000) >> 16; | |
| 70 | z = (*xa++ >> 16) + carry; | |
| 71 | carry = (z & 0x10000) >> 16; | |
| 72 | Storeinc(xc, z, y); | |
| 73 | } | |
| 74 | #else | |
| 75 | do { | |
| 76 | y = *xa++ + *xb++ + carry; | |
| 77 | carry = (y & 0x10000) >> 16; | |
| 78 | *xc++ = y & 0xffff; | |
| 79 | } | |
| 80 | while(xc < xe); | |
| 81 | xe += a->wds - b->wds; | |
| 82 | while(xc < xe) { | |
| 83 | y = *xa++ + carry; | |
| 84 | carry = (y & 0x10000) >> 16; | |
| 85 | *xc++ = y & 0xffff; | |
| 86 | } | |
| 87 | #endif | |
| 88 | if (carry) { | |
| 89 | if (c->wds == c->maxwds) { | |
| 90 | b = Balloc(c->k + 1); | |
| 91 | Bcopy(b, c); | |
| 92 | Bfree(c); | |
| 93 | c = b; | |
| 94 | } | |
| 95 | c->x[c->wds++] = 1; | |
| 96 | } | |
| 97 | return c; | |
| 98 | } |