Annotation of OpenXM_contrib/gmp/mpn/x86/mod_34lsub1.asm, Revision 1.1
1.1 ! ohara 1: dnl Generic x86 mpn_mod_32lsub1 -- mpn remainder modulo 2^24-1.
! 2:
! 3: dnl Copyright 2000, 2001, 2002 Free Software Foundation, Inc.
! 4: dnl
! 5: dnl This file is part of the GNU MP Library.
! 6: dnl
! 7: dnl The GNU MP Library is free software; you can redistribute it and/or
! 8: dnl modify it under the terms of the GNU Lesser General Public License as
! 9: dnl published by the Free Software Foundation; either version 2.1 of the
! 10: dnl License, or (at your option) any later version.
! 11: dnl
! 12: dnl The GNU MP Library is distributed in the hope that it will be useful,
! 13: dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
! 14: dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
! 15: dnl Lesser General Public License for more details.
! 16: dnl
! 17: dnl You should have received a copy of the GNU Lesser General Public
! 18: dnl License along with the GNU MP Library; see the file COPYING.LIB. If
! 19: dnl not, write to the Free Software Foundation, Inc., 59 Temple Place -
! 20: dnl Suite 330, Boston, MA 02111-1307, USA.
! 21:
! 22: include(`../config.m4')
! 23:
! 24:
! 25: C cycles/limb
! 26: C P5: 3.0
! 27: C P6: 3.66
! 28: C K6: 3.0
! 29: C K7: 1.3
! 30: C P4: 9
! 31:
! 32:
! 33: C mp_limb_t mpn_mod_34lsub1 (mp_srcptr src, mp_size_t size)
! 34: C
! 35:
! 36: defframe(PARAM_SIZE, 8)
! 37: defframe(PARAM_SRC, 4)
! 38:
! 39: dnl re-use parameter space
! 40: define(SAVE_EBX, `PARAM_SRC')
! 41:
! 42: TEXT
! 43: ALIGN(16)
! 44: PROLOGUE(mpn_mod_34lsub1)
! 45: deflit(`FRAME',0)
! 46:
! 47: movl PARAM_SIZE, %ecx
! 48: movl PARAM_SRC, %edx
! 49:
! 50: subl $2, %ecx
! 51: ja L(three_or_more)
! 52:
! 53: movl (%edx), %eax
! 54: jb L(one)
! 55:
! 56: movl 4(%edx), %ecx
! 57: movl %eax, %edx
! 58: shrl $24, %eax C src[0] low
! 59:
! 60: andl $0xFFFFFF, %edx C src[0] high
! 61: addl %edx, %eax
! 62: movl %ecx, %edx
! 63:
! 64: andl $0xFFFF, %ecx
! 65: shrl $16, %edx C src[1] high
! 66: addl %edx, %eax
! 67:
! 68: shll $8, %ecx C src[1] low
! 69: addl %ecx, %eax
! 70:
! 71: L(one):
! 72: ret
! 73:
! 74:
! 75: L(three_or_more):
! 76: C eax
! 77: C ebx
! 78: C ecx size-2
! 79: C edx src
! 80: C esi
! 81: C edi
! 82: C ebp
! 83:
! 84: movl %ebx, SAVE_EBX C and arrange 16-byte loop alignment
! 85: xorl %ebx, %ebx
! 86:
! 87: pushl %esi FRAME_pushl()
! 88: xorl %esi, %esi
! 89:
! 90: pushl %edi FRAME_pushl()
! 91: xorl %eax, %eax C and clear carry flag
! 92:
! 93:
! 94: C offset 0x40 here
! 95: L(top):
! 96: C eax acc 0mod3
! 97: C ebx acc 1mod3
! 98: C ecx counter, limbs
! 99: C edx src
! 100: C esi acc 2mod3
! 101: C edi
! 102: C ebp
! 103:
! 104: leal 12(%edx), %edx
! 105: leal -2(%ecx), %ecx
! 106:
! 107: adcl -12(%edx), %eax
! 108: adcl -8(%edx), %ebx
! 109: adcl -4(%edx), %esi
! 110:
! 111: decl %ecx
! 112: jg L(top)
! 113:
! 114:
! 115: C ecx is -2, -1 or 0 representing 0, 1 or 2 more limbs, respectively
! 116:
! 117: movl $0xFFFFFFFF, %edi
! 118: incl %ecx
! 119: js L(combine)
! 120:
! 121: adcl (%edx), %eax
! 122: movl $0xFFFFFF00, %edi
! 123: decl %ecx
! 124: js L(combine)
! 125:
! 126: adcl 4(%edx), %ebx
! 127: movl $0xFFFF0000, %edi
! 128:
! 129:
! 130: L(combine):
! 131: C eax acc 0mod3
! 132: C ebx acc 1mod3
! 133: C ecx
! 134: C edx
! 135: C esi acc 2mod3
! 136: C edi mask
! 137: C ebp
! 138:
! 139: sbbl %ecx, %ecx C carry
! 140: movl %eax, %edx C 0mod3
! 141:
! 142: shrl $24, %eax C 0mod3 high
! 143: andl %edi, %ecx C carry masked
! 144:
! 145: subl %ecx, %eax C apply carry
! 146: movl %ebx, %edi C 1mod3
! 147:
! 148: shrl $16, %ebx C 1mod3 high
! 149: andl $0x00FFFFFF, %edx C 0mod3 low
! 150:
! 151: addl %edx, %eax C apply 0mod3 low
! 152: andl $0xFFFF, %edi
! 153:
! 154: shll $8, %edi C 1mod3 low
! 155: addl %ebx, %eax C apply 1mod3 high
! 156:
! 157: addl %edi, %eax C apply 1mod3 low
! 158: movl %esi, %edx C 2mod3
! 159:
! 160: shrl $8, %esi C 2mod3 high
! 161: andl $0xFF, %edx C 2mod3 low
! 162:
! 163: shll $16, %edx C 2mod3 low
! 164: addl %esi, %eax C apply 2mod3 high
! 165:
! 166: addl %edx, %eax C apply 2mod3 low
! 167: popl %edi FRAME_popl()
! 168:
! 169: movl SAVE_EBX, %ebx
! 170: popl %esi FRAME_popl()
! 171:
! 172: ret
! 173:
! 174: EPILOGUE()
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