mirror of
git://sourceware.org/git/glibc.git
synced 2024-12-09 04:11:27 +08:00
111 lines
2.9 KiB
ArmAsm
111 lines
2.9 KiB
ArmAsm
|
/* Copyright (C) 1996 Free Software Foundation, Inc.
|
||
|
|
Contributed by Richard Henderson (rth@tamu.edu)
|
||
|
|
|
||
|
|
This file is part of the GNU C Library.
|
||
|
|
|
||
|
|
The GNU C Library is free software; you can redistribute it and/or
|
||
|
|
modify it under the terms of the GNU Library General Public License as
|
||
|
|
published by the Free Software Foundation; either version 2 of the
|
||
|
|
License, or (at your option) any later version.
|
||
|
|
|
||
|
|
The GNU C Library 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
|
||
|
|
Library General Public License for more details.
|
||
|
|
|
||
|
|
You should have received a copy of the GNU Library General Public
|
||
|
|
License along with the GNU C Library; see the file COPYING.LIB. If
|
||
|
|
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
|
||
|
|
Cambridge, MA 02139, USA. */
|
||
|
|
|
||
|
|
|
||
|
|
#include <sysdep.h>
|
||
|
|
|
||
|
|
#ifdef __linux__
|
||
|
|
# include <asm/gentrap.h>
|
||
|
|
# include <asm/pal.h>
|
||
|
|
#else
|
||
|
|
# include <machine/pal.h>
|
||
|
|
#endif
|
||
|
|
|
||
|
|
.set noat
|
||
|
|
|
||
|
|
.align 4
|
||
|
|
.globl div
|
||
|
|
.ent div
|
||
|
|
div:
|
||
|
|
.frame sp, 0, ra
|
||
|
|
#ifdef PROF
|
||
|
|
ldgp gp, 0(pv)
|
||
|
|
lda AT, _mcount
|
||
|
|
jsr AT, (AT), _mcount
|
||
|
|
.prologue 1
|
||
|
|
#else
|
||
|
|
.prologue 0
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#define dividend t0
|
||
|
|
#define divisor t1
|
||
|
|
#define mask t2
|
||
|
|
#define quotient t3
|
||
|
|
#define modulus t4
|
||
|
|
#define tmp1 t5
|
||
|
|
#define tmp2 t6
|
||
|
|
#define compare t7
|
||
|
|
|
||
|
|
/* find correct sign for input to unsigned divide loop. */
|
||
|
|
sextl a1, a1 # e0 :
|
||
|
|
sextl a2, a2 # .. e1 :
|
||
|
|
negl a1, dividend # e0 :
|
||
|
|
negl a2, divisor # .. e1 :
|
||
|
|
cmovge a1, a1, dividend # e0 :
|
||
|
|
cmovge a2, a2, divisor # .. e1 :
|
||
|
|
beq a2, $divbyzero # e1 :
|
||
|
|
unop # :
|
||
|
|
|
||
|
|
/* shift divisor left, using 3-bit shifts for 32-bit divides as we
|
||
|
|
can't overflow. Three-bit shifts will result in looping three
|
||
|
|
times less here, but can result in two loops more later. Thus
|
||
|
|
using a large shift isn't worth it (and s8addq pairs better than
|
||
|
|
a shift). */
|
||
|
|
|
||
|
|
1: cmpult divisor, modulus, compare # e0 :
|
||
|
|
s8addq divisor, zero, divisor # .. e1 :
|
||
|
|
s8addq mask, zero, mask # e0 :
|
||
|
|
bne compare, 1b # .. e1 :
|
||
|
|
|
||
|
|
/* start to go right again. */
|
||
|
|
2: addq quotient, mask, tmp2 # e1 :
|
||
|
|
srl mask, 1, mask # .. e0 :
|
||
|
|
cmpule divisor, modulus, compare # e0 :
|
||
|
|
subq modulus, divisor, tmp1 # .. e1 :
|
||
|
|
cmovne compare, tmp2, quotient # e1 :
|
||
|
|
srl divisor, 1, divisor # .. e0 :
|
||
|
|
cmovne compare, tmp1, modulus # e0 :
|
||
|
|
bne mask, 2b # .. e1 :
|
||
|
|
|
||
|
|
/* find correct sign for result. */
|
||
|
|
xor a1, a2, compare # e0 :
|
||
|
|
negl quotient, tmp1 # .. e1 :
|
||
|
|
negl modulus, tmp2 # e0 :
|
||
|
|
cmovlt compare, tmp1, quotient # .. e1 :
|
||
|
|
cmovlt a1, tmp2, modulus # e1 :
|
||
|
|
|
||
|
|
/* and store it away in the structure. */
|
||
|
|
stl quotient, 0(a0) # .. e0 :
|
||
|
|
mov a0, v0 # e1 :
|
||
|
|
stl modulus, 4(a0) # .. e0 :
|
||
|
|
ret # e1 :
|
||
|
|
|
||
|
|
$divbyzero:
|
||
|
|
mov a0, v0
|
||
|
|
ldiq a0, GEN_INTDIV
|
||
|
|
call_pal PAL_gentrap
|
||
|
|
|
||
|
|
/* if trap returns, return zero. */
|
||
|
|
stl zero, 0(v0)
|
||
|
|
stl zero, 4(v0)
|
||
|
|
ret
|
||
|
|
|
||
|
|
.end div
|