dnl PowerPC-64 mpn_add_n/mpn_sub_n -- mpn addition
and subtraction.
dnl Copyright 1999-2001, 2003-2005, 2007, 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 POWER3/PPC630 1.5
C POWER4/PPC970 2
C POWER5 2
C POWER6 2.63
C POWER7 2.25-2.87
C
This code is a little bit slower
for POWER3/PPC630 than the simple
code used
C previously, but it is much faster
for POWER4/PPC970. The reason
for the
C POWER3/PPC630 slowdown can be attributed to the saving
and restoring of 4
C registers.
C INPUT PARAMETERS
C rp r3
C up r4
C vp r5
C n r6
ifdef(`OPERATION_add_n
',`
define(ADDSUBC, adde)
define(ADDSUB, addc)
define(func, mpn_add_n)
define(func_nc, mpn_add_nc)
define(GENRVAL, `addi r3, r3, 1
')
define(SETCBR, `addic r0, $1, -1
')
define(CLRCB, `addic r0, r0, 0
')
')
ifdef(`OPERATION_sub_n
',`
define(ADDSUBC, subfe)
define(ADDSUB, subfc)
define(func, mpn_sub_n)
define(func_nc, mpn_sub_nc)
define(GENRVAL, `
neg r3, r3
')
define(SETCBR, `subfic r0, $1, 0
')
define(CLRCB, `addic r0, r1, -1
')
')
MULFUNC_PROLOGUE(mpn_add_n mpn_add_nc mpn_sub_n mpn_sub_nc)
ASM_START()
PROLOGUE(func_nc)
SETCBR(r7)
b L(ent)
EPILOGUE()
PROLOGUE(func)
CLRCB
L(ent): std r31, -8(r1)
std r30, -16(r1)
std r29, -24(r1)
std r28, -32(r1)
rldicl. r0, r6, 0,62 C r0 = n & 3, set cr0
cmpdi cr6, r0, 2
addi r6, r6, 3 C compute count...
srdi r6, r6, 2 C ...
for ctr
mtctr r6 C copy count into ctr
beq cr0, L(b00)
blt cr6, L(b01)
beq cr6, L(b10)
L(b11): ld r8, 0(r4) C load s1 limb
ld r9, 0(r5) C load s2 limb
ld r10, 8(r4) C load s1 limb
ld r11, 8(r5) C load s2 limb
ld r12, 16(r4) C load s1 limb
addi r4, r4, 24
ld r0, 16(r5) C load s2 limb
addi r5, r5, 24
ADDSUBC r29, r9, r8
ADDSUBC r30, r11, r10
ADDSUBC r31, r0, r12
std r29, 0(r3)
std r30, 8(r3)
std r31, 16(r3)
addi r3, r3, 24
bdnz L(go)
b L(
ret)
L(b01): ld r12, 0(r4) C load s1 limb
addi r4, r4, 8
ld r0, 0(r5) C load s2 limb
addi r5, r5, 8
ADDSUBC r31, r0, r12 C
add
std r31, 0(r3)
addi r3, r3, 8
bdnz L(go)
b L(
ret)
L(b10): ld r10, 0(r4) C load s1 limb
ld r11, 0(r5) C load s2 limb
ld r12, 8(r4) C load s1 limb
addi r4, r4, 16
ld r0, 8(r5) C load s2 limb
addi r5, r5, 16
ADDSUBC r30, r11, r10 C
add
ADDSUBC r31, r0, r12 C
add
std r30, 0(r3)
std r31, 8(r3)
addi r3, r3, 16
bdnz L(go)
b L(
ret)
L(b00): C INITCY C clear/set cy
L(go): ld r6, 0(r4) C load s1 limb
ld r7, 0(r5) C load s2 limb
ld r8, 8(r4) C load s1 limb
ld r9, 8(r5) C load s2 limb
ld r10, 16(r4) C load s1 limb
ld r11, 16(r5) C load s2 limb
ld r12, 24(r4) C load s1 limb
ld r0, 24(r5) C load s2 limb
bdz L(
end)
addi r4, r4, 32
addi r5, r5, 32
ALIGN(16)
L(top): ADDSUBC r28, r7, r6
ld r6, 0(r4) C load s1 limb
ld r7, 0(r5) C load s2 limb
ADDSUBC r29, r9, r8
ld r8, 8(r4) C load s1 limb
ld r9, 8(r5) C load s2 limb
ADDSUBC r30, r11, r10
ld r10, 16(r4) C load s1 limb
ld r11, 16(r5) C load s2 limb
ADDSUBC r31, r0, r12
ld r12, 24(r4) C load s1 limb
ld r0, 24(r5) C load s2 limb
std r28, 0(r3)
addi r4, r4, 32
std r29, 8(r3)
addi r5, r5, 32
std r30, 16(r3)
std r31, 24(r3)
addi r3, r3, 32
bdnz L(top) C decrement ctr
and loop back
L(
end): ADDSUBC r28, r7, r6
ADDSUBC r29, r9, r8
ADDSUBC r30, r11, r10
ADDSUBC r31, r0, r12
std r28, 0(r3)
std r29, 8(r3)
std r30, 16(r3)
std r31, 24(r3)
L(
ret): ld r31, -8(r1)
ld r30, -16(r1)
ld r29, -24(r1)
ld r28, -32(r1)
subfe r3, r0, r0 C -cy
GENRVAL
blr
EPILOGUE()
