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/* Copyright (c) 2017 SiFive Inc. All rights reserved.
This copyrighted material is made available to anyone wishing to use,
modify, copy, or redistribute it subject to the terms and conditions
of the BSD License. This program is distributed in the hope that
it will be useful, but WITHOUT ANY WARRANTY expressed or implied,
including the implied warranties of MERCHANTABILITY or FITNESS FOR
A PARTICULAR PURPOSE. A copy of this license is available at
http://www.opensource.org/licenses.
*/
#=========================================================================
# crt0.S : Entry point for RISC-V user programs
#=========================================================================
.text
.global _start
.type _start, @function
_start:
# Initialize global pointer
.option push
.option norelax
1:auipc gp, %pcrel_hi(__global_pointer$)
addi gp, gp, %pcrel_lo(1b)
.option pop
# Clear the bss segment
la a0, _edata
la a2, _end
sub a2, a2, a0
li a1, 0
call memset
la a0, __libc_fini_array # Register global termination functions
call atexit # to be called upon exit
call __libc_init_array # Run global initialization functions
lw a0, 0(sp) # a0 = argc
addi a1, sp, __SIZEOF_POINTER__ # a1 = argv
li a2, 0 # a2 = envp = NULL
call main
tail exit
.size _start, .-_start
.global _init
.type _init, @function
.global _fini
.type _fini, @function
_init:
_fini:
# These don't have to do anything since we use init_array/fini_array.
ret
.size _init, .-_init
.size _fini, .-_fini
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