libc/libgloss/lm32/crt0.S

65 lines
2.3 KiB
ArmAsm

/*
* Lattice Mico32 C startup code.
* Contributed by Jon Beniston <jon@beniston.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 THE AUTHOR OR CONTRIBUTORS 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.
*/
.section .boot, "ax", @progbits
/* Program starts here */
.global _start
_start:
/* Setup stack and global pointer */
mvhi sp, hi(_fstack)
ori sp, sp, lo(_fstack)
mvhi gp, hi(_gp)
ori gp, gp, lo(_gp)
/* Clear BSS */
mvhi r1, hi(_fbss)
ori r1, r1, lo(_fbss)
mvi r2, 0
mvhi r3, hi(_ebss)
ori r3, r3, lo(_ebss)
sub r3, r3, r1
calli memset
/* Call C++ constructors */
calli _init
/* Call C++ destructors on exit */
mvhi r1, hi(_fini)
ori r1, r1, lo(_fini)
calli atexit
/* Call main program */
mvi r1, 0
mvi r2, 0
mvi r3, 0
calli main
/* Call exit, which doesn't return, to perform any clean up */
calli exit