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 29 /* Please send bug reports to 30 David M. Gay 31 Bell Laboratories, Room 2C-463 32 600 Mountain Avenue 33 Murray Hill, NJ 07974-0636 34 U.S.A. 35 dmg@bell-labs.com 36 */ 37 38 #include "gdtoaimp.h" 39 40 Bigint * 41 #ifdef KR_headers 42 sum(a, b) Bigint *a; Bigint *b; 43 #else 44 sum(Bigint *a, Bigint *b) 45 #endif 46 { 47 Bigint *c; 48 ULong carry, *xc, *xa, *xb, *xe, y; 49 #ifdef Pack_32 50 ULong z; 51 #endif 52 53 if (a->wds < b->wds) { 54 c = b; b = a; a = c; 55 } 56 c = Balloc(a->k); 57 c->wds = a->wds; 58 carry = 0; 59 xa = a->x; 60 xb = b->x; 61 xc = c->x; 62 xe = xc + b->wds; 63 #ifdef Pack_32 64 do { 65 y = (*xa & 0xffff) + (*xb & 0xffff) + carry; 66 carry = (y & 0x10000) >> 16; 67 z = (*xa++ >> 16) + (*xb++ >> 16) + carry; 68 carry = (z & 0x10000) >> 16; 69 Storeinc(xc, z, y); 70 } 71 while(xc < xe); 72 xe += a->wds - b->wds; 73 while(xc < xe) { 74 y = (*xa & 0xffff) + carry; 75 carry = (y & 0x10000) >> 16; 76 z = (*xa++ >> 16) + carry; 77 carry = (z & 0x10000) >> 16; 78 Storeinc(xc, z, y); 79 } 80 #else 81 do { 82 y = *xa++ + *xb++ + carry; 83 carry = (y & 0x10000) >> 16; 84 *xc++ = y & 0xffff; 85 } 86 while(xc < xe); 87 xe += a->wds - b->wds; 88 while(xc < xe) { 89 y = *xa++ + carry; 90 carry = (y & 0x10000) >> 16; 91 *xc++ = y & 0xffff; 92 } 93 #endif 94 if (carry) { 95 if (c->wds == c->maxwds) { 96 b = Balloc(c->k + 1); 97 Bcopy(b, c); 98 Bfree(c); 99 c = b; 100 } 101 c->x[c->wds++] = 1; 102 } 103 return c; 104 } 105