dnl AMD64 mpn_gcd_11 -- 1 x 1 gcd.
dnl Based on the K7 gcd_1.asm, by Kevin Ryde. Rehacked
for AMD64 by Torbjorn
dnl Granlund.
dnl Copyright 2000-2002, 2005, 2009, 2011, 2012, 2017 Free Software
dnl 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/bit
C AMD K8,K9 5.5
C AMD K10 ?
C AMD bd1 ?
C AMD bd2 ?
C AMD bd3 ?
C AMD bd4 ?
C AMD bt1 7.1
C AMD bt2 ?
C AMD zn1 ?
C AMD zn2 ?
C Intel P4 ?
C Intel CNR ?
C Intel PNR ?
C Intel NHM ?
C Intel WSM ?
C Intel SBR ?
C Intel IBR ?
C Intel HWL ?
C Intel BWL ?
C Intel SKL ?
C Intel atom 9.1
C Intel SLM 6.9
C Intel GLM 6.0
C Intel GLM+ 5.8
C VIA nano ?
C ctz_table[n] is the number of trailing zeros on n,
or MAXSHIFT
if n==0.
deflit(MAXSHIFT, 7)
deflit(
MASK, eval((m4_lshift(1,MAXSHIFT))-1))
DEF_OBJECT(ctz_table,64)
.
byte MAXSHIFT
forloop(i,1,
MASK,
` .
byte m4_count_trailing_zeros(i)
')
END_OBJECT(ctz_table)
define(`u0
', `%rdi')
define(`v0
', `%rsi')
ABI_SUPPORT(DOS64)
ABI_SUPPORT(STD64)
ASM_START()
TEXT
ALIGN(64)
PROLOGUE(mpn_gcd_11)
FUNC_ENTRY(2)
LEA( ctz_table, %r8)
jmp L(ent)
ALIGN(16)
L(top): cmovc %rdx, u0 C u = |u - v|
cmovc %rax, v0 C v = min(u,v)
L(mid):
and $
MASK, R32(%rdx)
movzbl (%r8,%rdx), R32(%rcx)
jz L(shift_alot)
shr R8(%rcx), u0
L(ent):
mov u0, %rax
mov v0, %rdx
sub u0, %rdx
sub v0, u0
jnz L(top)
L(
end): C rax = result
C rdx = 0
for the benefit of internal gcd_22
call
FUNC_EXIT()
ret
L(shift_alot):
shr $MAXSHIFT, u0
mov u0, %rdx
jmp L(mid)
EPILOGUE()
