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.section ".data"
.comm environ, 4
.globl __progname
__progname:
.long L1
L1: .long 0 # null string plus padding
.section ".text"
.globl start
start:
.globl _start
.type _start,@function
_start:
# squirrel away the arguments for main
mr 13, 3
mr 14, 4
mr 15, 5
mr 16, 6
# make certain space exists on the stack for the
# 'stw X, 4(1)' at the beginning of functions.
subi 1, 1, 16
li 0, 0
stw 0, 0(1)
# determine the program name (__progname)
mr 4, 14
lwz 28, 0(4) # r28 = argv[0] (program name)
cmpwi 28, 0 # argv[0] == NULL?
beq call_main # yep forget setup of progname
mr 3, 28 # r3 = argv[0]
li 4, '/' # r4 = '/'
.extern strrchr
bl strrchr # strrchr(argv[0], '/')
cmpwi 3, 0 # == 0?
beq no_slash_found # not found, use argv[0] still in r28
addi 28, 3, 1 # was found, point at char after '/'
no_slash_found:
# store the address of the basename found in argv[0]
lis 31, __progname@HA
stw 28, __progname@L(31)
lis 26, environ@HA
stw 15, environ@L(26)
.globl __init
call_main:
#ifdef MCRT0
addis 3, 3, _mcleanup@ha
addi 3, 3, _mcleanup@l
bl atexit
addis 3, 3, eprol@ha
addi 3, 3, eprol@l
addis 4, 4, _etext@ha
addi 4, 4, _etext@l
bl monstartup
#endif
bl __init
# recover those saved registers
mr 3, 13
mr 4, 14
mr 5, 15
mr 6, 16
bl main
.extern exit
mr 13, 3
bl __fini
mr 3, 13
bl exit
eprol:
#if 0
.globl __main
__main:
#endif
.globl __eabi
.type __eabi,@function
__eabi:
blr
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