| /* 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 FreeBSD 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 |
