gcc/libgcc/config/rl78/divmodsi.S
DJ Delorie ceb2fc49ce mulsi3.S: Remove a few unneeded moves and branches.
* config/rl78/mulsi3.S: Remove a few unneeded moves and branches.
* config/rl78/vregs.h: New.
* config/rl78/signbit.S: New file.  Implements signbit function.
* config/rl78/divmodsi.S: New.
* config/rl78/divmodhi.S: New.
* config/rl78/divmodqi.S: New.
* config/rl78/t-rl78: Build them here...
* config/rl78/lib2div.c: ...but not here.

Co-Authored-By: Nick Clifton <nickc@redhat.com>

From-SVN: r202588
2013-09-14 02:13:18 -04:00

522 lines
8.2 KiB
ArmAsm

/* SImode div/mod functions for the GCC support library for the Renesas RL78 processors.
Copyright (C) 2012,2013 Free Software Foundation, Inc.
Contributed by Red Hat.
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published
by the Free Software Foundation; either version 3, or (at your
option) any later version.
GCC is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
License for more details.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
#ifndef __RL78_G10__
#include "vregs.h"
.macro make_generic which,need_result
.if \need_result
quot = r8
num = r12
den = r16
bit = r20
.else
num = r8
quot = r12
den = r16
bit = r20
.endif
quotH = quot+2
quotL = quot
quotB0 = quot
quotB1 = quot+1
quotB2 = quot+2
quotB3 = quot+3
numH = num+2
numL = num
numB0 = num
numB1 = num+1
numB2 = num+2
numB3 = num+3
#define denH bc
denL = den
denB0 = den
denB1 = den+1
#define denB2 c
#define denB3 b
bitH = bit+2
bitL = bit
bitB0 = bit
bitB1 = bit+1
bitB2 = bit+2
bitB3 = bit+3
num_lt_den\which:
.if \need_result
movw r8, #0
movw r10, #0
.else
movw ax, [sp+8]
movw r8, ax
movw ax, [sp+10]
movw r10, ax
.endif
ret
shift_den_bit16\which:
movw ax, denL
movw denH, ax
movw denL, #0
.if \need_result
movw ax, bitL
movw bitH, ax
movw bitL, #0
.else
mov a, bit
add a, #16
mov bit, a
.endif
br $shift_den_bit\which
;; These routines leave DE alone - the signed functions use DE
;; to store sign information that must remain intact
.if \need_result
generic_div:
.else
generic_mod:
.endif
;; (quot,rem) = 8[sp] /% 12[sp]
movw hl, sp
movw ax, [hl+14] ; denH
cmpw ax, [hl+10] ; numH
movw ax, [hl+12] ; denL
sknz
cmpw ax, [hl+8] ; numL
bh $num_lt_den\which
sel rb2
push ax ; denL
; push bc ; denH
push de ; bitL
push hl ; bitH - stored in BC
sel rb0
;; (quot,rem) = 16[sp] /% 20[sp]
;; copy numerator
movw ax, [hl+8]
movw numL, ax
movw ax, [hl+10]
movw numH, ax
;; copy denomonator
movw ax, [hl+12]
movw denL, ax
movw ax, [hl+14]
movw denH, ax
movw ax, denL
or a, denB2
or a, denB3 ; not x
cmpw ax, #0
bnz $den_not_zero\which
movw numL, #0
movw numH, #0
ret
den_not_zero\which:
.if \need_result
;; zero out quot
movw quotL, #0
movw quotH, #0
.endif
;; initialize bit to 1
movw bitL, #1
movw bitH, #0
; while (den < num && !(den & (1L << BITS_MINUS_1)))
.if 1
;; see if we can short-circuit a bunch of shifts
movw ax, denH
cmpw ax, #0
bnz $shift_den_bit\which
movw ax, denL
cmpw ax, numH
bnh $shift_den_bit16\which
.endif
shift_den_bit\which:
movw ax, denH
mov1 cy,a.7
bc $enter_main_loop\which
cmpw ax, numH
movw ax, denL ; we re-use this below
sknz
cmpw ax, numL
bh $enter_main_loop\which
;; den <<= 1
; movw ax, denL ; already has it from the cmpw above
shlw ax, 1
movw denL, ax
; movw ax, denH
rolwc denH, 1
; movw denH, ax
;; bit <<= 1
.if \need_result
movw ax, bitL
shlw ax, 1
movw bitL, ax
movw ax, bitH
rolwc ax, 1
movw bitH, ax
.else
;; if we don't need to compute the quotent, we don't need an
;; actual bit *mask*, we just need to keep track of which bit
inc bitB0
.endif
br $shift_den_bit\which
;; while (bit)
main_loop\which:
;; if (num >= den) (cmp den > num)
movw ax, numH
cmpw ax, denH
movw ax, numL
sknz
cmpw ax, denL
skz
bnh $next_loop\which
;; num -= den
; movw ax, numL ; already has it from the cmpw above
subw ax, denL
movw numL, ax
movw ax, numH
sknc
decw ax
subw ax, denH
movw numH, ax
.if \need_result
;; res |= bit
mov a, quotB0
or a, bitB0
mov quotB0, a
mov a, quotB1
or a, bitB1
mov quotB1, a
mov a, quotB2
or a, bitB2
mov quotB2, a
mov a, quotB3
or a, bitB3
mov quotB3, a
.endif
next_loop\which:
;; den >>= 1
movw ax, denH
shrw ax, 1
movw denH, ax
mov a, denB1
rorc a, 1
mov denB1, a
mov a, denB0
rorc a, 1
mov denB0, a
;; bit >>= 1
.if \need_result
movw ax, bitH
shrw ax, 1
movw bitH, ax
mov a, bitB1
rorc a, 1
mov bitB1, a
mov a, bitB0
rorc a, 1
mov bitB0, a
.else
dec bitB0
.endif
enter_main_loop\which:
.if \need_result
movw ax, bitH
cmpw ax, #0
bnz $main_loop\which
.else
cmp bitB0, #15
bh $main_loop\which
.endif
;; bit is HImode now; check others
movw ax, numH ; numerator
cmpw ax, #0
bnz $bit_high_set\which
movw ax, denH ; denominator
cmpw ax, #0
bz $switch_to_himode\which
bit_high_set\which:
.if \need_result
movw ax, bitL
cmpw ax, #0
.else
cmp0 bitB0
.endif
bnz $main_loop\which
switch_to_himode\which:
.if \need_result
movw ax, bitL
cmpw ax, #0
.else
cmp0 bitB0
.endif
bz $main_loop_done_himode\which
;; From here on in, r22, r14, and r18 are all zero
;; while (bit)
main_loop_himode\which:
;; if (num >= den) (cmp den > num)
movw ax, denL
cmpw ax, numL
bh $next_loop_himode\which
;; num -= den
movw ax, numL
subw ax, denL
movw numL, ax
movw ax, numH
sknc
decw ax
subw ax, denH
movw numH, ax
.if \need_result
;; res |= bit
mov a, quotB0
or a, bitB0
mov quotB0, a
mov a, quotB1
or a, bitB1
mov quotB1, a
.endif
next_loop_himode\which:
;; den >>= 1
movw ax, denL
shrw ax, 1
movw denL, ax
.if \need_result
;; bit >>= 1
movw ax, bitL
shrw ax, 1
movw bitL, ax
.else
dec bitB0
.endif
.if \need_result
movw ax, bitL
cmpw ax, #0
.else
cmp0 bitB0
.endif
bnz $main_loop_himode\which
main_loop_done_himode\which:
sel rb2
pop hl ; bitH - stored in BC
pop de ; bitL
; pop bc ; denH
pop ax ; denL
sel rb0
ret
.endm
make_generic _d 1
make_generic _m 0
;----------------------------------------------------------------------
.global ___udivsi3
.type ___udivsi3,@function
___udivsi3:
;; r8 = 4[sp] / 8[sp]
call $!generic_div
ret
.size ___udivsi3, . - ___udivsi3
.global ___umodsi3
.type ___umodsi3,@function
___umodsi3:
;; r8 = 4[sp] % 8[sp]
call $!generic_mod
ret
.size ___umodsi3, . - ___umodsi3
;----------------------------------------------------------------------
.macro neg_ax
movw hl, ax
movw ax, #0
subw ax, [hl]
movw [hl], ax
movw ax, #0
sknc
decw ax
subw ax, [hl+2]
movw [hl+2], ax
.endm
.global ___divsi3
.type ___divsi3,@function
___divsi3:
;; r8 = 4[sp] / 8[sp]
movw de, #0
mov a, [sp+7]
mov1 cy, a.7
bc $div_signed_num
mov a, [sp+11]
mov1 cy, a.7
bc $div_signed_den
call $!generic_div
ret
div_signed_num:
;; neg [sp+4]
movw ax, sp
addw ax, #4
neg_ax
mov d, #1
mov a, [sp+11]
mov1 cy, a.7
bnc $div_unsigned_den
div_signed_den:
;; neg [sp+8]
movw ax, sp
addw ax, #8
neg_ax
mov e, #1
div_unsigned_den:
call $!generic_div
mov a, d
cmp0 a
bz $div_skip_restore_num
;; We have to restore the numerator [sp+4]
movw ax, sp
addw ax, #4
neg_ax
mov a, d
div_skip_restore_num:
xor a, e
bz $div_no_neg
movw ax, #r8
neg_ax
div_no_neg:
mov a, e
cmp0 a
bz $div_skip_restore_den
;; We have to restore the denominator [sp+8]
movw ax, sp
addw ax, #8
neg_ax
div_skip_restore_den:
ret
.size ___divsi3, . - ___divsi3
.global ___modsi3
.type ___modsi3,@function
___modsi3:
;; r8 = 4[sp] % 8[sp]
movw de, #0
mov a, [sp+7]
mov1 cy, a.7
bc $mod_signed_num
mov a, [sp+11]
mov1 cy, a.7
bc $mod_signed_den
call $!generic_mod
ret
mod_signed_num:
;; neg [sp+4]
movw ax, sp
addw ax, #4
neg_ax
mov d, #1
mov a, [sp+11]
mov1 cy, a.7
bnc $mod_unsigned_den
mod_signed_den:
;; neg [sp+8]
movw ax, sp
addw ax, #8
neg_ax
mov e, #1
mod_unsigned_den:
call $!generic_mod
mov a, d
cmp0 a
bz $mod_no_neg
movw ax, #r8
neg_ax
;; We have to restore [sp+4] as well.
movw ax, sp
addw ax, #4
neg_ax
mod_no_neg:
.if 1
mov a, e
cmp0 a
bz $mod_skip_restore_den
movw ax, sp
addw ax, #8
neg_ax
mod_skip_restore_den:
.endif
ret
.size ___modsi3, . - ___modsi3
#endif