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dnl SPARC mpn_sub_n -- Subtract two limb vectors of the same length > 0 and
dnl store difference in a third limb vector.
dnl Copyright (C) 1995, 1996, 2000 Free Software Foundation, Inc.
dnl This file is part of the GNU MP Library.
dnl The GNU MP Library is free software; you can redistribute it and/or modify
dnl it under the terms of the GNU Lesser General Public License as published
dnl by the Free Software Foundation; either version 2.1 of the License, or (at
dnl your option) any later version.
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 Lesser General Public
dnl License for more details.
dnl You should have received a copy of the GNU Lesser General Public License
dnl along with the GNU MP Library; see the file COPYING.LIB. If not, write to
dnl the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
dnl MA 02111-1307, USA.
include(`../config.m4')
C INPUT PARAMETERS
define(res_ptr,%o0)
define(s1_ptr,%o1)
define(s2_ptr,%o2)
define(n,%o3)
ASM_START()
PROLOGUE(mpn_sub_n)
xor s2_ptr,res_ptr,%g1
andcc %g1,4,%g0
bne L(1) C branch if alignment differs
nop
C ** V1a **
andcc res_ptr,4,%g0 C res_ptr unaligned? Side effect: cy=0
be L(v1) C if no, branch
nop
C Add least significant limb separately to align res_ptr and s2_ptr
ld [s1_ptr],%g4
add s1_ptr,4,s1_ptr
ld [s2_ptr],%g2
add s2_ptr,4,s2_ptr
add n,-1,n
subcc %g4,%g2,%o4
st %o4,[res_ptr]
add res_ptr,4,res_ptr
L(v1): addx %g0,%g0,%o4 C save cy in register
cmp n,2 C if n < 2 ...
bl L(end2) C ... branch to tail code
subcc %g0,%o4,%g0 C restore cy
ld [s1_ptr+0],%g4
addcc n,-10,n
ld [s1_ptr+4],%g1
ldd [s2_ptr+0],%g2
blt L(fin1)
subcc %g0,%o4,%g0 C restore cy
C Add blocks of 8 limbs until less than 8 limbs remain
L(loop1):
subxcc %g4,%g2,%o4
ld [s1_ptr+8],%g4
subxcc %g1,%g3,%o5
ld [s1_ptr+12],%g1
ldd [s2_ptr+8],%g2
std %o4,[res_ptr+0]
subxcc %g4,%g2,%o4
ld [s1_ptr+16],%g4
subxcc %g1,%g3,%o5
ld [s1_ptr+20],%g1
ldd [s2_ptr+16],%g2
std %o4,[res_ptr+8]
subxcc %g4,%g2,%o4
ld [s1_ptr+24],%g4
subxcc %g1,%g3,%o5
ld [s1_ptr+28],%g1
ldd [s2_ptr+24],%g2
std %o4,[res_ptr+16]
subxcc %g4,%g2,%o4
ld [s1_ptr+32],%g4
subxcc %g1,%g3,%o5
ld [s1_ptr+36],%g1
ldd [s2_ptr+32],%g2
std %o4,[res_ptr+24]
addx %g0,%g0,%o4 C save cy in register
addcc n,-8,n
add s1_ptr,32,s1_ptr
add s2_ptr,32,s2_ptr
add res_ptr,32,res_ptr
bge L(loop1)
subcc %g0,%o4,%g0 C restore cy
L(fin1):
addcc n,8-2,n
blt L(end1)
subcc %g0,%o4,%g0 C restore cy
C Add blocks of 2 limbs until less than 2 limbs remain
L(loope1):
subxcc %g4,%g2,%o4
ld [s1_ptr+8],%g4
subxcc %g1,%g3,%o5
ld [s1_ptr+12],%g1
ldd [s2_ptr+8],%g2
std %o4,[res_ptr+0]
addx %g0,%g0,%o4 C save cy in register
addcc n,-2,n
add s1_ptr,8,s1_ptr
add s2_ptr,8,s2_ptr
add res_ptr,8,res_ptr
bge L(loope1)
subcc %g0,%o4,%g0 C restore cy
L(end1):
subxcc %g4,%g2,%o4
subxcc %g1,%g3,%o5
std %o4,[res_ptr+0]
addx %g0,%g0,%o4 C save cy in register
andcc n,1,%g0
be L(ret1)
subcc %g0,%o4,%g0 C restore cy
C Add last limb
ld [s1_ptr+8],%g4
ld [s2_ptr+8],%g2
subxcc %g4,%g2,%o4
st %o4,[res_ptr+8]
L(ret1):
retl
addx %g0,%g0,%o0 C return carry-out from most sign. limb
L(1): xor s1_ptr,res_ptr,%g1
andcc %g1,4,%g0
bne L(2)
nop
C ** V1b **
andcc res_ptr,4,%g0 C res_ptr unaligned? Side effect: cy=0
be L(v1b) C if no, branch
nop
C Add least significant limb separately to align res_ptr and s1_ptr
ld [s2_ptr],%g4
add s2_ptr,4,s2_ptr
ld [s1_ptr],%g2
add s1_ptr,4,s1_ptr
add n,-1,n
subcc %g2,%g4,%o4
st %o4,[res_ptr]
add res_ptr,4,res_ptr
L(v1b): addx %g0,%g0,%o4 C save cy in register
cmp n,2 C if n < 2 ...
bl L(end2) C ... branch to tail code
subcc %g0,%o4,%g0 C restore cy
ld [s2_ptr+0],%g4
addcc n,-10,n
ld [s2_ptr+4],%g1
ldd [s1_ptr+0],%g2
blt L(fin1b)
subcc %g0,%o4,%g0 C restore cy
C Add blocks of 8 limbs until less than 8 limbs remain
L(loop1b):
subxcc %g2,%g4,%o4
ld [s2_ptr+8],%g4
subxcc %g3,%g1,%o5
ld [s2_ptr+12],%g1
ldd [s1_ptr+8],%g2
std %o4,[res_ptr+0]
subxcc %g2,%g4,%o4
ld [s2_ptr+16],%g4
subxcc %g3,%g1,%o5
ld [s2_ptr+20],%g1
ldd [s1_ptr+16],%g2
std %o4,[res_ptr+8]
subxcc %g2,%g4,%o4
ld [s2_ptr+24],%g4
subxcc %g3,%g1,%o5
ld [s2_ptr+28],%g1
ldd [s1_ptr+24],%g2
std %o4,[res_ptr+16]
subxcc %g2,%g4,%o4
ld [s2_ptr+32],%g4
subxcc %g3,%g1,%o5
ld [s2_ptr+36],%g1
ldd [s1_ptr+32],%g2
std %o4,[res_ptr+24]
addx %g0,%g0,%o4 C save cy in register
addcc n,-8,n
add s1_ptr,32,s1_ptr
add s2_ptr,32,s2_ptr
add res_ptr,32,res_ptr
bge L(loop1b)
subcc %g0,%o4,%g0 C restore cy
L(fin1b):
addcc n,8-2,n
blt L(end1b)
subcc %g0,%o4,%g0 C restore cy
C Add blocks of 2 limbs until less than 2 limbs remain
L(loope1b):
subxcc %g2,%g4,%o4
ld [s2_ptr+8],%g4
subxcc %g3,%g1,%o5
ld [s2_ptr+12],%g1
ldd [s1_ptr+8],%g2
std %o4,[res_ptr+0]
addx %g0,%g0,%o4 C save cy in register
addcc n,-2,n
add s1_ptr,8,s1_ptr
add s2_ptr,8,s2_ptr
add res_ptr,8,res_ptr
bge L(loope1b)
subcc %g0,%o4,%g0 C restore cy
L(end1b):
subxcc %g2,%g4,%o4
subxcc %g3,%g1,%o5
std %o4,[res_ptr+0]
addx %g0,%g0,%o4 C save cy in register
andcc n,1,%g0
be L(ret1b)
subcc %g0,%o4,%g0 C restore cy
C Add last limb
ld [s2_ptr+8],%g4
ld [s1_ptr+8],%g2
subxcc %g2,%g4,%o4
st %o4,[res_ptr+8]
L(ret1b):
retl
addx %g0,%g0,%o0 C return carry-out from most sign. limb
C ** V2 **
C If we come here, the alignment of s1_ptr and res_ptr as well as the
C alignment of s2_ptr and res_ptr differ. Since there are only two ways
C things can be aligned (that we care about) we now know that the alignment
C of s1_ptr and s2_ptr are the same.
L(2): cmp n,1
be L(jone)
nop
andcc s1_ptr,4,%g0 C s1_ptr unaligned? Side effect: cy=0
be L(v2) C if no, branch
nop
C Add least significant limb separately to align s1_ptr and s2_ptr
ld [s1_ptr],%g4
add s1_ptr,4,s1_ptr
ld [s2_ptr],%g2
add s2_ptr,4,s2_ptr
add n,-1,n
subcc %g4,%g2,%o4
st %o4,[res_ptr]
add res_ptr,4,res_ptr
L(v2): addx %g0,%g0,%o4 C save cy in register
addcc n,-8,n
blt L(fin2)
subcc %g0,%o4,%g0 C restore cy
C Add blocks of 8 limbs until less than 8 limbs remain
L(loop2):
ldd [s1_ptr+0],%g2
ldd [s2_ptr+0],%o4
subxcc %g2,%o4,%g2
st %g2,[res_ptr+0]
subxcc %g3,%o5,%g3
st %g3,[res_ptr+4]
ldd [s1_ptr+8],%g2
ldd [s2_ptr+8],%o4
subxcc %g2,%o4,%g2
st %g2,[res_ptr+8]
subxcc %g3,%o5,%g3
st %g3,[res_ptr+12]
ldd [s1_ptr+16],%g2
ldd [s2_ptr+16],%o4
subxcc %g2,%o4,%g2
st %g2,[res_ptr+16]
subxcc %g3,%o5,%g3
st %g3,[res_ptr+20]
ldd [s1_ptr+24],%g2
ldd [s2_ptr+24],%o4
subxcc %g2,%o4,%g2
st %g2,[res_ptr+24]
subxcc %g3,%o5,%g3
st %g3,[res_ptr+28]
addx %g0,%g0,%o4 C save cy in register
addcc n,-8,n
add s1_ptr,32,s1_ptr
add s2_ptr,32,s2_ptr
add res_ptr,32,res_ptr
bge L(loop2)
subcc %g0,%o4,%g0 C restore cy
L(fin2):
addcc n,8-2,n
blt L(end2)
subcc %g0,%o4,%g0 C restore cy
L(loope2):
ldd [s1_ptr+0],%g2
ldd [s2_ptr+0],%o4
subxcc %g2,%o4,%g2
st %g2,[res_ptr+0]
subxcc %g3,%o5,%g3
st %g3,[res_ptr+4]
addx %g0,%g0,%o4 C save cy in register
addcc n,-2,n
add s1_ptr,8,s1_ptr
add s2_ptr,8,s2_ptr
add res_ptr,8,res_ptr
bge L(loope2)
subcc %g0,%o4,%g0 C restore cy
L(end2):
andcc n,1,%g0
be L(ret2)
subcc %g0,%o4,%g0 C restore cy
C Add last limb
L(jone):
ld [s1_ptr],%g4
ld [s2_ptr],%g2
subxcc %g4,%g2,%o4
st %o4,[res_ptr]
L(ret2):
retl
addx %g0,%g0,%o0 C return carry-out from most sign. limb
EPILOGUE(mpn_sub_n)
|
