* inital implementation

2025-08-16 05:51:26 +02:00 · 2004-11-05 12:47:45 +00:00 · 2004-11-05 12:47:45 +00:00 · c8fcac29f0
commit c8fcac29f0
parent e2b9b82c7f
1 changed files with 137 additions and 0 deletions
--- a/rtl/linux/arm/crt0.as
+++ b/rtl/linux/arm/crt0.as
@ -0,0 +1,137 @@
+/* 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., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 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]
+
+        /* Fetch address of fini */
+        ldr ip, =__libc_csu_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, =__libc_csu_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 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
+
+/*
+  $Log$
+  Revision 1.2  2004-11-05 12:47:45  florian
+    * inital implementation
+*/