dnl Intel Atom mpn_bdiv_dbm1.
dnl Contributed to the GNU project by Torbjorn Granlund and Marco Bodrato.
dnl Copyright 2011 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 cycles/limb
C P5 -
C P6 model 0-8,10-12 -
C P6 model 9 (Banias) 9.75
C P6 model 13 (Dothan)
C P4 model 0 (Willamette)
C P4 model 1 (?)
C P4 model 2 (Northwood) 8.25
C P4 model 3 (Prescott)
C P4 model 4 (Nocona)
C Intel Atom 8
C AMD K6 -
C AMD K7 -
C AMD K8
C AMD K10
C TODO: This code was optimised for atom-32, consider moving it back to atom
C dir(atom currently grabs this code), and write a 4-way version(7c/l).
defframe(PARAM_CARRY,20)
defframe(PARAM_MUL, 16)
defframe(PARAM_SIZE, 12)
defframe(PARAM_SRC, 8)
defframe(PARAM_DST, 4)
dnl re-use parameter space
define(SAVE_RP,`PARAM_MUL')
define(SAVE_UP,`PARAM_SIZE')
define(`rp', `%edi')
define(`up', `%esi')
define(`n', `%ecx')
define(`reg', `%edx')
define(`cy', `%eax') C contains the return value
ASM_START()
TEXT
ALIGN(16)
deflit(`FRAME',0)
PROLOGUE(mpn_bdiv_dbm1c)
mov PARAM_SIZE, n C size
mov up, SAVE_UP
mov PARAM_SRC, up
movd PARAM_MUL, %mm7
mov rp, SAVE_RP
mov PARAM_DST, rp
movd (up), %mm0
pmuludq %mm7, %mm0
shr n
mov PARAM_CARRY, cy
jz L(eq1)
movd 4(up), %mm1
jc L(odd)
lea 4(up), up
pmuludq %mm7, %mm1
movd %mm0, reg
psrlq $32, %mm0
sub reg, cy
movd %mm0, reg
movq %mm1, %mm0
dec n
mov cy, (rp)
lea 4(rp), rp
jz L(end)
C ALIGN(16)
L(top): movd 4(up), %mm1
sbb reg, cy
L(odd): movd %mm0, reg
psrlq $32, %mm0
pmuludq %mm7, %mm1
sub reg, cy
lea 8(up), up
movd %mm0, reg
movd (up), %mm0
mov cy, (rp)
sbb reg, cy
movd %mm1, reg
psrlq $32, %mm1
sub reg, cy
movd %mm1, reg
pmuludq %mm7, %mm0
dec n
mov cy, 4(rp)
lea 8(rp), rp
jnz L(top)
L(end): sbb reg, cy
L(eq1): movd %mm0, reg
psrlq $32, %mm0
mov SAVE_UP, up
sub reg, cy
movd %mm0, reg
emms
mov cy, (rp)
sbb reg, cy
mov SAVE_RP, rp
ret
EPILOGUE()
ASM_END()