dnl ARM v6 mpn_modexact_1c_odd
dnl Contributed to the GNU project by Torbjörn Granlund.
dnl Copyright 2012 Free Software Foundation,
Inc.
dnl
This file is part of the GNU MP Library.
dnl
dnl The GNU MP Library is free software
; you can redistribute it and/or modify
dnl it under the terms of either:
dnl
dnl * the GNU Lesser General
Public License as published by the Free
dnl Software Foundation
; either version 3 of the License, or (at your
dnl
option) any later
version.
dnl
dnl
or
dnl
dnl * the GNU General
Public License as published by the Free Software
dnl Foundation
; either version 2 of the License, or (at your option) any
dnl later
version.
dnl
dnl
or both in parallel, as here.
dnl
dnl The GNU MP Library is distributed in the hope that it will be useful, but
dnl WITHOUT ANY WARRANTY
; without even the implied warranty of MERCHANTABILITY
dnl
or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU General
Public License
dnl
for more details.
dnl
dnl You should have received copies of the GNU General
Public License
and the
dnl GNU Lesser General
Public License along with the GNU MP Library.
If not,
dnl see
https://www.gnu.org/licenses/.
include(`../config.m4
')
C cycles/limb
C StrongARM -
C XScale -
C Cortex-A7 ?
C Cortex-A8 ?
C Cortex-A9 9
C Cortex-A15 7
C Architecture requirements:
C v5 -
C v5t -
C v5te smulbb
C v6 umaal
C v6t2 -
C v7a -
define(`up
', `r0')
define(`n
', `r1')
define(`d
', `r2')
define(`cy
', `r3')
.protected binvert_limb_table
ASM_START()
PROLOGUE(mpn_modexact_1c_odd)
stmfd sp!, {r4, r5, r6, r7}
LEA( r4, binvert_limb_table)
ldr r6, [up], #4 C up[0]
and r12, d, #254
ldrb r4, [r4, r12, lsr #1]
smulbb r12, r4, r4
mul r12, d, r12
rsb r12, r12, r4, asl #1
mul r4, r12, r12
mul r4, d, r4
rsb r4, r4, r12, asl #1 C r4 = inverse
subs n, n, #1
sub r6, r6, cy
mul r6, r6, r4
beq L(
end)
rsb r5, r4, #0 C r5 = -inverse
L(top): ldr r7, [up], #4
mov r12, #0
umaal r12, cy, r6, d
mul r6, r7, r4
mla r6, cy, r5, r6
subs n, n, #1
bne L(top)
L(
end):
mov r12, #0
umaal r12, cy, r6, d
mov r0, cy
ldmfd sp!, {r4, r5, r6, r7}
bx r14
EPILOGUE()