/* -*-comment-start: "//";comment-end:""-*- * GNU Mes --- Maxwell Equations of Software * Copyright © 2018,2023 Jan (janneke) Nieuwenhuizen * Copyright © 2021 W. J. van der Laan * * This file is part of GNU Mes. * * GNU Mes is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 3 of the License, or (at * your option) any later version. * * GNU Mes is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with GNU Mes. If not, see . */ #include "mes/lib-mini.h" int main (int argc, char *argv[], char *envp[]); /* mesc will generate the following preamble: push ra push fp */ int _start () { // environ is &argv[argc + 1] asm ("mv_____%t1,%fp"); asm ("addi___%t1,%t1,$i8_8 !0x1"); // 0x10 to skip over pushed fp+ra, 0x8 to skip over argc asm ("addi___%t5,%fp,$i8_0 !0x1"); // 0x10 to skip over pushed fp+ra asm ("ld_____%t0,0(%t5)"); asm ("addi___%t0,%t0,1"); asm ("li_____%t5,$i32 %0x3"); // skip over all arguments and the final NULL asm ("sll____%t0,%t0,%t5"); asm ("add____%t0,%t0,%t1"); asm ("push___%t0"); // envp asm ("push___%t1"); // argv asm ("sd_____%t0,0(%t1)"); asm ("addi___%t5,%fp,$i8_0 !0x1"); // 0x10 to skip over pushed fp+ra asm ("ld_____%t0,0(%t5)"); asm ("push___%t0"); // argc __init_io (); main (); asm ("mv_____%a0,%t0"); asm ("li_____%a7,SYS_exit"); asm ("ecall"); asm ("ebreak"); }