Retro68/gcc/libgcc/config/rl78/mulsi3.S
Wolfgang Thaller aaf905ce07 add gcc 4.70
2012-03-28 01:13:14 +02:00

236 lines
3.7 KiB
ArmAsm

; Copyright (C) 2011 Free Software Foundation, Inc.
; Contributed by Red Hat.
;
; This file 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.
;
; This file 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/>.
;; 32x32=32 multiply
; real
; GAS defines r0..r7 as aliases for real registers; we want the saddr
; forms here.
r_0 = 0xffef8
r_1 = 0xffef9
r_2 = 0xffefa
r_3 = 0xffefb
r_4 = 0xffefc
r_5 = 0xffefd
r_6 = 0xffefe
r_7 = 0xffeff
; clobberable
r8 = 0xffef0
r9 = 0xffef1
r10 = 0xffef2
r11 = 0xffef3
r12 = 0xffef4
r13 = 0xffef5
r14 = 0xffef6
r15 = 0xffef7
; preserved
r16 = 0xffee8
r17 = 0xffee9
r18 = 0xffeea
r19 = 0xffeeb
r20 = 0xffeec
r21 = 0xffeed
r22 = 0xffeee
r23 = 0xffeef
;----------------------------------------------------------------------
; Register use:
; RB0 RB1 RB2
; AX op2L res32L res32H
; BC op2H (resH) op1
; DE count (resL-tmp)
; HL [sp+4]
.text
nop
.global ___mulsi3 ; (USI a, USI b)
___mulsi3:
;; A is at [sp+4]
;; B is at [sp+8]
;; result is in R8..R11
movw ax, sp
addw ax, #4
movw hl, ax
sel rb2
push ax
push bc
sel rb0
clrw ax
movw r8, ax
movw r16, ax
movw ax, [hl+6]
cmpw ax, #0
bz $1f
cmpw ax, #0xffff
bnz $2f
movw ax, [hl]
sel rb1
subw ax, r_0
sel rb0
br $1f
2:
movw bc, ax
movw ax, [hl]
cmpw ax, #0
skz
call !.Lmul_hi
1:
movw ax, [hl+2]
cmpw ax, #0
bz $1f
cmpw ax, #0xffff
bnz $2f
movw ax, [hl+4]
sel rb1
subw ax, r_0
sel rb0
br $1f
2:
movw bc, ax
movw ax, [hl+4]
cmpw ax, #0
skz
call !.Lmul_hi
1:
movw ax, r8
movw r16, ax
clrw ax
movw r8, ax
;; now do R16:R8 += op1L * op2L
;; op1 is in AX.0 (needs to shrw)
;; op2 is in BC.2 and BC.1 (bc can shlw/rolcw)
;; res is in AX.2 and AX.1 (needs to addw)
movw ax, [hl]
movw r10, ax ; BC.1
movw ax, [hl+4]
cmpw ax, r10
bc $.Lmul_hisi_top
movw bc, r10
movw r10, ax
movw ax, bc
.Lmul_hisi_top:
movw bc, #0
.Lmul_hisi_loop:
shrw ax, 1
bnc $.Lmul_hisi_no_add
sel rb1
addw ax, bc
sel rb2
sknc
incw ax
addw ax, r_2
.Lmul_hisi_no_add:
sel rb1
shlw bc, 1
sel rb0
rolwc bc, 1
cmpw ax, #0
bz $.Lmul_hisi_done
shrw ax, 1
bnc $.Lmul_hisi_no_add2
sel rb1
addw ax, bc
sel rb2
sknc
incw ax
addw ax, r_2
.Lmul_hisi_no_add2:
sel rb1
shlw bc, 1
sel rb0
rolwc bc, 1
cmpw ax, #0
bnz $.Lmul_hisi_loop
.Lmul_hisi_done:
movw ax, r16
movw r10, ax
sel rb2
pop bc
pop ax
sel rb0
ret
;----------------------------------------------------------------------
;; R8 += AX * BC
.Lmul_hi:
cmpw ax, bc
skc
xchw ax, bc
br $.Lmul_hi_loop
.Lmul_hi_top:
sel rb1
addw ax, r_2
sel rb0
.Lmul_hi_no_add:
shlw bc, 1
.Lmul_hi_loop:
shrw ax, 1
bc $.Lmul_hi_top
cmpw ax, #0
bz $.Lmul_hi_done
shlw bc, 1
shrw ax, 1
bc $.Lmul_hi_top
cmpw ax, #0
bnz $.Lmul_hi_no_add
.Lmul_hi_done:
ret
;----------------------------------------------------------------------
.global ___mulhi3
___mulhi3:
sel rb1
clrw ax
sel rb0
movw ax, sp
addw ax, #4
movw hl, ax
movw ax, [hl+2]
movw bc, ax
movw ax, [hl]
br $.Lmul_hi