Annotation of OpenXM_contrib/gmp/mpn/arm/submul_1.asm, Revision 1.1
1.1 ! ohara 1: dnl ARM mpn_submul_1 -- Multiply a limb vector with a limb and subtract the
! 2: dnl result from a second limb vector.
! 3: dnl Based on mpn_addmul_1, which was contributed by Robert Harley.
! 4:
! 5: dnl Copyright 1998, 2000, 2001 Free Software Foundation, Inc.
! 6:
! 7: dnl This file is part of the GNU MP Library.
! 8:
! 9: dnl The GNU MP Library is free software; you can redistribute it and/or modify
! 10: dnl it under the terms of the GNU Lesser General Public License as published
! 11: dnl by the Free Software Foundation; either version 2.1 of the License, or (at
! 12: dnl your option) any later version.
! 13:
! 14: dnl The GNU MP Library is distributed in the hope that it will be useful, but
! 15: dnl WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
! 16: dnl or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
! 17: dnl License for more details.
! 18:
! 19: dnl You should have received a copy of the GNU Lesser General Public License
! 20: dnl along with the GNU MP Library; see the file COPYING.LIB. If not, write to
! 21: dnl the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
! 22: dnl MA 02111-1307, USA.
! 23:
! 24: include(`../config.m4')
! 25:
! 26: C This runs at 9.75 cycles/limb in the StrongARM.
! 27:
! 28: C Could use some register cleanup. Some fewer registers might be needed, or
! 29: C r11 could be utilized for better speed. Could avoid saving all registers for
! 30: C small (n <= 3) operands.
! 31:
! 32: define(`rp',`r0')
! 33: define(`up',`r1')
! 34: define(`n',`r2')
! 35: define(`v',`r3')
! 36:
! 37: ASM_START()
! 38: PROLOGUE(mpn_submul_1)
! 39: stmfd sp!, { r4-r10, lr }
! 40: mov r4, #0
! 41: movs n, n, lsr #1
! 42: bcc L(skip1)
! 43: ldr lr, [up], #4
! 44: umull r4, r12, v, lr
! 45: ldr r6, [rp]
! 46: subs r6, r6, r4
! 47: sbc r4, r0, r0
! 48: sub r4, r12, r4
! 49: str r6, [rp], #4
! 50: L(skip1):
! 51: movs n, n, lsr #1
! 52: bcc L(skip2)
! 53: ldmia up!, { r9, r10 }
! 54: mov r5, #0
! 55: umlal r4, r5, v, r9
! 56: mov r9, #0
! 57: umlal r5, r9, v, r10
! 58: ldmia rp, { r6, r7 }
! 59: subs r6, r6, r4
! 60: sbcs r7, r7, r5
! 61: sbc r4, r0, r0
! 62: sub r4, r9, r4
! 63: stmia rp!, { r6, r7 }
! 64: L(skip2):
! 65: teq n, #0
! 66: beq L(return)
! 67:
! 68: L(submul_loop):
! 69: ldmia up!, { r9, r10, r12, lr }
! 70: mov r5, #0
! 71: umlal r4, r5, v, r9
! 72: mov r9, #0
! 73: umlal r5, r9, v, r10
! 74: mov r10, #0
! 75: umlal r9, r10, v, r12
! 76: mov r12, #0
! 77: umlal r10, r12, v, lr
! 78: ldmia rp, { r6, r7, r8, lr }
! 79: subs r6, r6, r4
! 80: sbcs r7, r7, r5
! 81: sbcs r8, r8, r9
! 82: sbcs lr, lr, r10
! 83: sbc r4, r0, r0
! 84: sub r4, r12, r4
! 85: subs n, n, #1
! 86: stmia rp!, { r6, r7, r8, lr }
! 87: bne L(submul_loop)
! 88: L(return):
! 89: mov r0, r4
! 90: ldmfd sp!, { r4-r10, pc }
! 91: EPILOGUE(mpn_submul_1)
FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>