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/* Based on ../i386/crt0.S and newlib's libgloss/frv/crt0.S */
/*
When we enter this piece of code, the program stack looks like this:
argc argument counter (integer)
argv[0] program name (pointer)
argv[1...N] program args (pointers)
argv[argc-1] end of args (integer)
NULL
env[0...N] environment variables (pointers)
NULL
Also, GR16 holds a pointer to a memory map. */
#include <features.h>
.text
.global _start
.type _start,%function
#if defined L_crt0 || defined L_Scrt0 || ! defined __UCLIBC_CTOR_DTOR__
.type __uClibc_main,%function
#else
.weak _init
.weak _fini
.type __uClibc_start_main,%function
#endif
_start:
/* Make sure the stack pointer is properly aligned. Save the
original value in gr21 such that we can get to arguments and
such from there. */
mov.p sp, gr21
andi sp, #-8, sp
/* At program start-up, gr16 contains a pointer to a memory
map, that we use to relocate addresses. */
call .Lcall
.Lcall:
movsg lr, gr4
sethi.p #gprelhi(.Lcall), gr5
setlo #gprello(.Lcall), gr5
sub.p gr4, gr5, gr4
/* gr4 now holds the _gp address. */
mov gr16, gr8
sethi.p #gprelhi(__ROFIXUP_LIST__), gr9
sethi #gprelhi(__ROFIXUP_END__), gr10
setlo.p #gprello(__ROFIXUP_LIST__), gr9
setlo #gprello(__ROFIXUP_END__), gr10
add.p gr9, gr4, gr9
add gr10, gr4, gr10
call __self_reloc
mov.p gr8, gr17
mov gr8, gr15
/*add-----------------------*/
sethi.p #gprelhi(__g_mem_map1), gr8
setlo #gprello(__g_mem_map1), gr8
/*
sethi.p 0x0,gr9
setlo 0x0,gr9
*/
st gr16, @(gr15, gr8)
/* ------------------------------------ */
/* gr17 now holds the self-relocated _GLOBAL_OFFSET_TABLE_
address, because the linker added its unrelocated address as
the last entry in the ROFIXUP list, and __self_reloc returns
the last entry, relocated. */
/* Prepare arguments for uClibc main. */
ld @(gr21, gr0), gr8
slli gr8, #2, gr10
add gr21, gr10, gr10
addi.p gr21, #4, gr9
addi gr10, #8, gr10
/* Set up an invalid (NULL return address, NULL frame pointer)
callers stack frame so anybody unrolling the stack knows where
to stop */
mov gr0, fp
movgs gr0, lr
#if (defined L_crt1 || defined L_gcrt1 || defined L_Scrt1) && defined __UCLIBC_CTOR_DTOR__
/* Pass .init and .fini arguments to __uClibc_start_main(). */
sethi.p #gotfuncdeschi(_init), gr11
sethi #gotfuncdeschi(_fini), gr12
setlo.p #gotfuncdesclo(_init), gr11
setlo #gotfuncdesclo(_fini), gr12
ld.p @(gr11, gr17), gr11
mov gr17, gr15
ld.p @(gr12, gr17), gr12
call __uClibc_start_main
#else
mov.p gr17, gr15
call __uClibc_main
#endif
/* Crash if somehow `exit' returns anyways. */
jmpl @(gr0,gr0)
.size _start,.-_start
#if 1
/* defined by sheng yu*/
.data
.globl __data_start
__data_start:
.global __g_mem_map1
// .hidden __g_mem_map1
__g_mem_map1:
.long 8
.weak __g_mem_map = __data_start
#endif
#if 0
.data
.globl __g_mem_map
__g_mem_map:
.long 0
.globl __g_sr_got
__g_sr_got:
.long 0
#endif
#if defined L_gcrt1 && defined __UCLIBC_PROFILING__
# include "./gmon-start.S"
#endif