about summary refs log tree commit diff
path: root/sysdeps/alpha/crti.S
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/alpha/crti.S')
-rw-r--r--sysdeps/alpha/crti.S99
1 files changed, 99 insertions, 0 deletions
diff --git a/sysdeps/alpha/crti.S b/sysdeps/alpha/crti.S
new file mode 100644
index 0000000000..f49d13648f
--- /dev/null
+++ b/sysdeps/alpha/crti.S
@@ -0,0 +1,99 @@
+/* Special .init and .fini section support for Alpha.
+   Copyright (C) 2001-2014 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.
+
+   In addition to the permissions in the GNU Lesser General Public
+   License, the Free Software Foundation gives you unlimited
+   permission to link the compiled version of this file with other
+   programs, and to distribute those programs without any restriction
+   coming from the use of this file. (The GNU Lesser General Public
+   License restrictions do apply in other respects; for example, they
+   cover modification of the file, and distribution when not linked
+   into another program.)
+
+   Note that people who make modified versions of this file are not
+   obligated to grant this special exception for their modified
+   versions; it is their choice whether to do so. The GNU Lesser
+   General Public License gives permission to release a modified
+   version without this exception; this exception also makes it
+   possible to release a modified version which carries forward this
+   exception.
+
+   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, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* crti.S puts a function prologue at the beginning of the .init and
+   .fini sections and defines global symbols for those addresses, so
+   they can be called as functions.  The symbols _init and _fini are
+   magic and cause the linker to emit DT_INIT and DT_FINI.
+
+   This differs from what would be generated for ordinary code in that
+   we save and restore the GP within the function.  In order for linker
+   relaxation to work, the value in the GP register on exit from a function
+   must be valid for the function entry point.  Normally, a function is
+   contained within one object file and this is not an issue, provided
+   that the function reloads the gp after making any function calls.
+   However, _init and _fini are constructed from pieces of many object
+   files, all of which may have different GP values.  So we must reload
+   the GP value from crti.o in crtn.o.  */
+
+#include <libc-symbols.h>
+#include <sysdep.h>
+
+#ifndef PREINIT_FUNCTION
+# define PREINIT_FUNCTION __gmon_start__
+#endif
+
+#ifndef PREINIT_FUNCTION_WEAK
+# define PREINIT_FUNCTION_WEAK 1
+#endif
+
+#if PREINIT_FUNCTION_WEAK
+        weak_extern (PREINIT_FUNCTION)
+#else
+        .hidden PREINIT_FUNCTION
+#endif
+
+	.section .init, "ax", @progbits
+	.globl	_init
+	.type	_init, @function
+	.usepv	_init, std
+_init:
+	ldgp	$29, 0($27)
+	subq	$30, 16, $30
+#if PREINIT_FUNCTION_WEAK
+	lda	$27, PREINIT_FUNCTION
+#endif
+	stq	$26, 0($30)
+	stq	$29, 8($30)
+#if PREINIT_FUNCTION_WEAK
+	beq	$27, 1f
+	jsr	$26, ($27), PREINIT_FUNCTION
+	ldq	$29, 8($30)
+1:
+#else
+	bsr	$26, PREINIT_FUNCTION !samegp
+#endif
+	.p2align 3
+
+	.section .fini, "ax", @progbits
+	.globl	_fini
+	.type	_fini,@function
+	.usepv	_fini,std
+_fini:
+	ldgp	$29, 0($27)
+	subq	$30, 16, $30
+	stq	$26, 0($30)
+	stq	$29, 8($30)
+	.p2align 3