libc/libgloss/rx/crt0.S

205 lines
5.0 KiB
ArmAsm

/* Copyright (c) 2008, 2009, 2011 Red Hat Incorporated.
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
The name of Red Hat Incorporated may not be used to endorse
or promote products derived from this software without specific
prior written permission.
This software is provided by the copyright holders and contributors
"AS IS" and any express or implied warranties, including, but not
limited to, the implied warranties of merchantability and fitness for
a particular purpose are disclaimed. In no event shall Red Hat
incorporated be liable for any direct, indirect, incidental, special,
exemplary, or consequential damages (including, but not limited to,
procurement of substitute goods or services; loss of use, data, or
profits; or business interruption) however caused and on any theory of
liability, whether in contract, strict liability, or tort (including
negligence or otherwise) arising in any way out of the use of this
software, even if advised of the possibility of such damage. */
.text
.global _start
_start:
.LFB2:
mvtc #0, psw
/* Enable the DN bit - this should have been done for us by
the CPU reset, but it is best to make sure for ourselves. */
mvtc #0x100, fpsw
mov #__stack, r0
mvtc #__vectors, intb
/* Copy the .data section from ROM into RAM. */
mov #__datastart, r1
mov #__romdatastart, r2
mov #__romdatacopysize, r3
#ifdef __RX_DISALLOW_STRING_INSNS__
cmp #0, r3
beq 2f
1: mov.b [r2+], r5
mov.b r5, [r1+]
sub #1, r3
bne 1b
2:
#else
smovf
#endif
/* Initialise the contents of the .bss section. */
mov #__bssstart, r1
mov #0, r2
mov #__bsssize, r3
sstr.l
/* Initialize data pointer register(s).
Note: The registers used here should agree with the definition of
GP_BASE_REGNUM in gcc/config/rx/rx.h.
Note: We are assuming that -mint-register has not been used when
compiling the application. */
#ifdef _RX_PID
/* Initialise the constant data pointer and small data pointers. */
mov #__pid_base, r13
mov #__gp, r12
#else
/* Initialise the small data area pointer. */
mov #__gp, r13
#endif
bsr.a __rx_init
#ifdef PROFILE_SUPPORT /* Defined in gcrt0.S. */
mov # _start, r1
mov # _etext, r2
bsr.a __monstartup
#endif
mov #0, r1 /* argc */
mov #0, r2 /* argv */
mov #0, r3 /* envv */
bsr.a _main
.LFE2:
#ifdef PROFILE_SUPPORT
mov r1, r13 ; Save return code.
bsr.a __mcleanup
mov r13, r1
#endif
bsr.a _exit
.global _rx_run_preinit_array
.type _rx_run_preinit_array,@function
_rx_run_preinit_array:
mov #__preinit_array_start,r1
mov #__preinit_array_end,r2
bra.a _rx_run_inilist
.global _rx_run_init_array
.type _rx_run_init_array,@function
_rx_run_init_array:
mov #__init_array_start,r1
mov #__init_array_end,r2
mov #4, r3
bra.a _rx_run_inilist
.global _rx_run_fini_array
.type _rx_run_fini_array,@function
_rx_run_fini_array:
mov #__fini_array_start,r2
mov #__fini_array_end,r1
mov #-4, r3
/* fall through */
_rx_run_inilist:
next_inilist:
cmp r1,r2
beq.b done_inilist
mov.l [r1],r4
cmp #-1, r4
beq.b skip_inilist
cmp #0, r4
beq.b skip_inilist
pushm r1-r3
jsr r4
popm r1-r3
skip_inilist:
add r3,r1
bra.b next_inilist
done_inilist:
rts
.section .init,"ax"
.global __rx_init
__rx_init:
.section .fini,"ax"
.global __rx_fini
__rx_fini:
bsr.a _rx_run_fini_array
.section .rodata
.balign 4
.global __pid_base
.weak __pid_base
__pid_base:
.section .sdata
.balign 4
.global __gp
.weak __gp
__gp:
.section .data
.global ___dso_handle
.weak ___dso_handle
___dso_handle:
.long 0
;;; Provide Dwarf unwinding information that will help GDB stop
;;; backtraces at the right place. This is stolen from assembly
;;; code generated by GCC with -dA.
.section .debug_frame,"",@progbits
.Lframe0:
.4byte .LECIE0-.LSCIE0 ; Length of Common Information Entry
.LSCIE0:
.4byte 0xffffffff ; CIE Identifier Tag
.byte 0x1 ; CIE Version
.ascii "\0" ; CIE Augmentation
.uleb128 0x1 ; CIE Code Alignment Factor
.sleb128 -1 ; CIE Data Alignment Factor
.byte 0xd ; CIE RA Column
.byte 0xc ; DW_CFA_def_cfa
.uleb128 0xc
.uleb128 0x3
.byte 0x8d ; DW_CFA_offset, column 0xd
.uleb128 0x3
.p2align 2
.LECIE0:
.LSFDE0:
.4byte .LEFDE0-.LASFDE0 ; FDE Length
.LASFDE0:
.4byte .Lframe0 ; FDE CIE offset
.4byte .LFB2 ; FDE initial location
.4byte .LFE2-.LFB2 ; FDE address range
.byte 0xf ; DW_CFA_def_cfa_expression
.uleb128 1 ; length of expression
.byte 0x30 ; DW_OP_lit0
.p2align 2
.LEFDE0:
.text