+ initial revision

rtl/linux/x86_64/prt0.as

@@ -0,0 +1,73 @@
+#
+#   $Id$
+#   This file is part of the Free Pascal run time library.
+#   Copyright (c) 2002 by Florian Klaempfl
+#   members of the Free Pascal development team.
+#
+#   See the file COPYING.FPC, included in this distribution,
+#   for details about the copyright.
+#
+#   This program 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.
+#
+#**********************************************************************}
+#
+# Linux ELF startup code for Free Pascal
+#
+
+/* This is the canonical entry point, usually the first thing in the text
+   segment.  The SVR4/i386 ABI (pages 3-31, 3-32) says that when the entry
+   point runs, most registers' values are unspecified, except for:
+
+   %rdx		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.
+
+   %rsp		The stack contains the arguments and environment:
+		0(%rsp)			argc
+		8(%rsp)			argv[0]
+		...
+		(8*argc)(%rsp)		NULL
+		(8*(argc+1))(%rsp)	envp[0]
+		...
+					NULL
+*/
+
+        .text
+	.globl _start
+	.type _start,@function
+_start:
+#       movq %rdx,%r9                 /* Address of the shared library termination
+#               	                 function.  */
+	popq     %rsi		      /* Pop the argument count.  */
+        movq     %rsi,U_SYSTEM_ARGC
+	movq     %rsp,U_SYSTEM_ARGV   /* argv starts just at the current stack top.  */
+        leaq     8(%rsi,,8),%rax
+        addq     %esp,%rax
+        movq     %rax,U_SYSTEM_ENVP
+        andq     $~15,%rsp            /* Align the stack to a 16 byte boundary to follow the ABI.  */
+
+/* !!!! CPU initialization? */
+
+        xorq    %rbp, %rbp
+        call    PASCALMAIN
+
+	hlt                           /* Crash if somehow `exit' does return.	 */
+
+/*!!!! hlt syscall? */
+
+/* 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
+#
+# $Log$
+# Revision 1.1  2003-01-06 19:33:10  florian
+#   + initial revision
+#
+#