diff options
Diffstat (limited to 'riscv_new/rtl/linux/riscv32/cprt0.as')
| -rw-r--r-- | riscv_new/rtl/linux/riscv32/cprt0.as | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/riscv_new/rtl/linux/riscv32/cprt0.as b/riscv_new/rtl/linux/riscv32/cprt0.as new file mode 100644 index 0000000000..5b9474e9c3 --- /dev/null +++ b/riscv_new/rtl/linux/riscv32/cprt0.as @@ -0,0 +1,139 @@ +/* Startup code for ARM & ELF + Copyright (C) 1995, 1996, 1997, 1998, 2001, 2002 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, + MA 02110-1301, USA. */ + +/* This is the canonical entry point, usually the first thing in the text + segment. + + Note that the code in the .init section has already been run. + This includes _init and _libc_init + + + At this entry point, most registers' values are unspecified, except: + + a1 Contains a function pointer to be registered with `atexit'. + This is how the dynamic linker arranges to have DT_FINI + functions called for shared libraries that have been loaded + before this code runs. + + sp The stack contains the arguments and environment: + 0(sp) argc + 4(sp) argv[0] + ... + (4*argc)(sp) NULL + (4*(argc+1))(sp) envp[0] + ... + NULL +*/ + + .text + .globl _start + .type _start,function +_start: + /* Clear the frame pointer since this is the outermost frame. */ + mov fp, #0 + ldmia sp!, {a2} + + /* Pop argc off the stack and save a pointer to argv */ + ldr ip,=operatingsystem_parameter_argc + ldr a3,=operatingsystem_parameter_argv + str a2,[ip] + + /* calc envp */ + add a4,a2,#1 + add a4,sp,a4,LSL #2 + ldr ip,=operatingsystem_parameter_envp + + str sp,[a3] + str a4,[ip] + + /* Save initial stackpointer */ + ldr ip,=__stkptr + str sp,[ip] + + /* Fetch address of fini */ + ldr ip, =_fini + + /* argc already loaded to a2*/ + + /* load argv */ + mov a3, sp + + /* Push stack limit */ + str a3, [sp, #-4]! + + /* Push rtld_fini */ + str a1, [sp, #-4]! + + /* Set up the other arguments in registers */ + ldr a1, =PASCALMAIN + ldr a4, =_init + + /* Push fini */ + str ip, [sp, #-4]! + + /* __libc_start_main (main, argc, argv, init, fini, rtld_fini, stack_end) */ + + /* Let the libc call main and exit with its return code. */ + bl __libc_start_main + + /* should never get here....*/ + bl abort + + .globl _haltproc + .type _haltproc,function +_haltproc: + ldr r0,=operatingsystem_result + ldrb r0,[r0] + swi 0x900001 + b _haltproc + + /* Define a symbol for the first piece of initialized data. */ + .data + .globl __data_start +__data_start: + .long 0 + .weak data_start + data_start = __data_start + +.bss + .comm __stkptr,4 + + .comm operatingsystem_parameter_envp,4 + .comm operatingsystem_parameter_argc,4 + .comm operatingsystem_parameter_argv,4 + + .section ".comment" + .byte 0 + .ascii "generated by FPC http://www.freepascal.org\0" + +/* We need this stuff to make gdb behave itself, otherwise + gdb will chokes with SIGILL when trying to debug apps. +*/ + .section ".note.ABI-tag", "a" + .align 4 + .long 1f - 0f + .long 3f - 2f + .long 1 +0: .asciz "GNU" +1: .align 4 +2: .long 0 + .long 2,0,0 +3: .align 4 + +.section .note.GNU-stack,"",%progbits |