Annotation of OpenXM/src/kan96xx/gmp-2.0.2-ssh-2/mpn/power/mul_1.s, Revision 1.1
1.1 ! takayama 1: # IBM POWER __mpn_mul_1 -- Multiply a limb vector with a limb and store
! 2: # the result in a second limb vector.
! 3:
! 4: # Copyright (C) 1992, 1994 Free Software Foundation, Inc.
! 5:
! 6: # This file is part of the GNU MP Library.
! 7:
! 8: # The GNU MP Library is free software; you can redistribute it and/or modify
! 9: # it under the terms of the GNU Library General Public License as published by
! 10: # the Free Software Foundation; either version 2 of the License, or (at your
! 11: # option) any later version.
! 12:
! 13: # The GNU MP Library is distributed in the hope that it will be useful, but
! 14: # WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
! 15: # or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
! 16: # License for more details.
! 17:
! 18: # You should have received a copy of the GNU Library General Public License
! 19: # along with the GNU MP Library; see the file COPYING.LIB. If not, write to
! 20: # the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
! 21: # MA 02111-1307, USA.
! 22:
! 23:
! 24: # INPUT PARAMETERS
! 25: # res_ptr r3
! 26: # s1_ptr r4
! 27: # size r5
! 28: # s2_limb r6
! 29:
! 30: # The RS/6000 has no unsigned 32x32->64 bit multiplication instruction. To
! 31: # obtain that operation, we have to use the 32x32->64 signed multiplication
! 32: # instruction, and add the appropriate compensation to the high limb of the
! 33: # result. We add the multiplicand if the multiplier has its most significant
! 34: # bit set, and we add the multiplier if the multiplicand has its most
! 35: # significant bit set. We need to preserve the carry flag between each
! 36: # iteration, so we have to compute the compensation carefully (the natural,
! 37: # srai+and doesn't work). Since the POWER architecture has a branch unit
! 38: # we can branch in zero cycles, so that's how we perform the additions.
! 39:
! 40: .toc
! 41: .csect .__mpn_mul_1[PR]
! 42: .align 2
! 43: .globl __mpn_mul_1
! 44: .globl .__mpn_mul_1
! 45: .csect __mpn_mul_1[DS]
! 46: __mpn_mul_1:
! 47: .long .__mpn_mul_1[PR], TOC[tc0], 0
! 48: .csect .__mpn_mul_1[PR]
! 49: .__mpn_mul_1:
! 50:
! 51: cal 3,-4(3)
! 52: l 0,0(4)
! 53: cmpi 0,6,0
! 54: mtctr 5
! 55: mul 9,0,6
! 56: srai 7,0,31
! 57: and 7,7,6
! 58: mfmq 8
! 59: ai 0,0,0 # reset carry
! 60: cax 9,9,7
! 61: blt Lneg
! 62: Lpos: bdz Lend
! 63: Lploop: lu 0,4(4)
! 64: stu 8,4(3)
! 65: cmpi 0,0,0
! 66: mul 10,0,6
! 67: mfmq 0
! 68: ae 8,0,9
! 69: bge Lp0
! 70: cax 10,10,6 # adjust high limb for negative limb from s1
! 71: Lp0: bdz Lend0
! 72: lu 0,4(4)
! 73: stu 8,4(3)
! 74: cmpi 0,0,0
! 75: mul 9,0,6
! 76: mfmq 0
! 77: ae 8,0,10
! 78: bge Lp1
! 79: cax 9,9,6 # adjust high limb for negative limb from s1
! 80: Lp1: bdn Lploop
! 81: b Lend
! 82:
! 83: Lneg: cax 9,9,0
! 84: bdz Lend
! 85: Lnloop: lu 0,4(4)
! 86: stu 8,4(3)
! 87: cmpi 0,0,0
! 88: mul 10,0,6
! 89: cax 10,10,0 # adjust high limb for negative s2_limb
! 90: mfmq 0
! 91: ae 8,0,9
! 92: bge Ln0
! 93: cax 10,10,6 # adjust high limb for negative limb from s1
! 94: Ln0: bdz Lend0
! 95: lu 0,4(4)
! 96: stu 8,4(3)
! 97: cmpi 0,0,0
! 98: mul 9,0,6
! 99: cax 9,9,0 # adjust high limb for negative s2_limb
! 100: mfmq 0
! 101: ae 8,0,10
! 102: bge Ln1
! 103: cax 9,9,6 # adjust high limb for negative limb from s1
! 104: Ln1: bdn Lnloop
! 105: b Lend
! 106:
! 107: Lend0: cal 9,0(10)
! 108: Lend: st 8,4(3)
! 109: aze 3,9
! 110: br
FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>