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/* Copyright (C) 2004-2020 Free Software Foundation, Inc.
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 Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library. If not, see
<https://www.gnu.org/licenses/>. */
/* Common bits for implementing software divide. */
#include <sysdep.h>
#ifdef __linux__
# include <asm/gentrap.h>
# include <asm/pal.h>
#else
# include <machine/pal.h>
#endif
/* These are not normal C functions. Argument registers are t10 and t11;
the result goes in t12; the return address is in t9. Only t12 and AT
may be clobbered. */
#define X t10
#define Y t11
#define RV t12
#define RA t9
/* The secureplt format does not allow the division routines to be called
via plt; there aren't enough registers free to be clobbered. Avoid
setting the symbol type to STT_FUNC, so that the linker won't be tempted
to create a plt entry. */
#define funcnoplt notype
/* None of these functions should use implicit anything. */
.set nomacro
.set noat
/* Code fragment to invoke _mcount for profiling. This should be invoked
directly after allocation of the stack frame. */
.macro CALL_MCOUNT
#ifdef PROF
stq ra, 0(sp)
stq pv, 8(sp)
stq gp, 16(sp)
cfi_rel_offset (ra, 0)
cfi_rel_offset (pv, 8)
cfi_rel_offset (gp, 16)
br AT, 1f
.set macro
1: ldgp gp, 0(AT)
mov RA, ra
lda AT, _mcount
jsr AT, (AT), _mcount
.set nomacro
ldq ra, 0(sp)
ldq pv, 8(sp)
ldq gp, 16(sp)
cfi_restore (ra)
cfi_restore (pv)
cfi_restore (gp)
/* Realign subsequent code with what we'd have without this
macro at all. This means aligned with one arithmetic insn
used within the bundle. */
.align 4
nop
#endif
.endm
/* In order to make the below work, all top-level divide routines must
use the same frame size. */
#define FRAME 64
/* Code fragment to generate an integer divide-by-zero fault. When
building libc.so, we arrange for there to be one copy of this code
placed late in the dso, such that all branches are forward. When
building libc.a, we use multiple copies to avoid having an out of
range branch. Users should jump to DIVBYZERO. */
.macro DO_DIVBYZERO
#ifdef PIC
#define DIVBYZERO __divbyzero
.section .gnu.linkonce.t.divbyzero, "ax", @progbits
.globl __divbyzero
.type __divbyzero, @function
.usepv __divbyzero, no
.hidden __divbyzero
#else
#define DIVBYZERO $divbyzero
#endif
.align 4
DIVBYZERO:
cfi_startproc
cfi_return_column (RA)
cfi_def_cfa_offset (FRAME)
mov a0, RV
unop
lda a0, GEN_INTDIV
call_pal PAL_gentrap
mov RV, a0
clr RV
lda sp, FRAME(sp)
cfi_def_cfa_offset (0)
ret $31, (RA), 1
cfi_endproc
.size DIVBYZERO, .-DIVBYZERO
.endm
/* Like the ev6 instructions, but fall back to stack use on prior machines. */
.arch ev6
.macro _ITOFS gr, fr, slot
#ifdef __alpha_fix__
itofs \gr, \fr
#else
stl \gr, \slot(sp)
lds \fr, \slot(sp)
#endif
.endm
.macro _ITOFT gr, fr, slot
#ifdef __alpha_fix__
itoft \gr, \fr
#else
stq \gr, \slot(sp)
ldt \fr, \slot(sp)
#endif
.endm
.macro _FTOIT fr, gr, slot
#ifdef __alpha_fix__
ftoit \fr, \gr
#else
stt \fr, \slot(sp)
ldq \gr, \slot(sp)
#endif
.endm
/* Similarly, but move two registers. Schedules better for pre-ev6. */
.macro _ITOFT2 gr1, fr1, slot1, gr2, fr2, slot2
#ifdef __alpha_fix__
itoft \gr1, \fr1
itoft \gr2, \fr2
#else
stq \gr1, \slot1(sp)
stq \gr2, \slot2(sp)
ldt \fr1, \slot1(sp)
ldt \fr2, \slot2(sp)
#endif
.endm
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