about summary refs log tree commit diff
path: root/REORG.TODO/sysdeps/x86_64/x32/dl-machine.h
diff options
context:
space:
mode:
authorZack Weinberg <zackw@panix.com>2017-06-08 15:39:03 -0400
committerZack Weinberg <zackw@panix.com>2017-06-08 15:39:03 -0400
commit5046dbb4a7eba5eccfd258f92f4735c9ffc8d069 (patch)
tree4470480d904b65cf14ca524f96f79eca818c3eaf /REORG.TODO/sysdeps/x86_64/x32/dl-machine.h
parent199fc19d3aaaf57944ef036e15904febe877fc93 (diff)
downloadglibc-zack/build-layout-experiment.tar.gz
glibc-zack/build-layout-experiment.tar.xz
glibc-zack/build-layout-experiment.zip
Prepare for radical source tree reorganization. zack/build-layout-experiment
All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).
Diffstat (limited to 'REORG.TODO/sysdeps/x86_64/x32/dl-machine.h')
-rw-r--r--REORG.TODO/sysdeps/x86_64/x32/dl-machine.h86
1 files changed, 86 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/x86_64/x32/dl-machine.h b/REORG.TODO/sysdeps/x86_64/x32/dl-machine.h
new file mode 100644
index 0000000000..2c50688d94
--- /dev/null
+++ b/REORG.TODO/sysdeps/x86_64/x32/dl-machine.h
@@ -0,0 +1,86 @@
+/* Machine-dependent ELF dynamic relocation inline functions.  x32 version.
+   Copyright (C) 2012-2017 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, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* Must allow <sysdeps/x86_64/dl-machine.h> to be included more than once.
+   See #ifdef RESOLVE_MAP in sysdeps/x86_64/dl-machine.h.  */
+#include <sysdeps/x86_64/dl-machine.h>
+
+#ifndef _X32_DL_MACHINE_H
+#define _X32_DL_MACHINE_H
+
+#undef ARCH_LA_PLTENTER
+#undef ARCH_LA_PLTEXIT
+#undef RTLD_START
+
+/* Names of the architecture-specific auditing callback functions.  */
+#define ARCH_LA_PLTENTER x32_gnu_pltenter
+#define ARCH_LA_PLTEXIT x32_gnu_pltexit
+
+/* Initial entry point code for the dynamic linker.
+   The C function `_dl_start' is the real entry point;
+   its return value is the user program's entry point.  */
+#define RTLD_START asm ("\n\
+.text\n\
+	.p2align 4\n\
+.globl _start\n\
+.globl _dl_start_user\n\
+_start:\n\
+	movl %esp, %edi\n\
+	call _dl_start\n\
+_dl_start_user:\n\
+	# Save the user entry point address in %r12.\n\
+	movl %eax, %r12d\n\
+	# See if we were run as a command with the executable file\n\
+	# name as an extra leading argument.\n\
+	movl _dl_skip_args(%rip), %eax\n\
+	# Pop the original argument count.\n\
+	movl (%rsp), %edx\n\
+	# Adjust the stack pointer to skip _dl_skip_args words.\n\
+	lea 4(%rsp,%rax,4), %esp\n\
+	# Subtract _dl_skip_args from argc.\n\
+	subl %eax, %edx\n\
+	# Push argc back on the stack.\n\
+	subl $4, %esp\n\
+	movl %edx, (%rsp)\n\
+	# Call _dl_init (struct link_map *main_map, int argc, char **argv, char **env)\n\
+	# argc -> rsi\n\
+	movl %edx, %esi\n\
+	# Save %rsp value in %r13.\n\
+	movl %esp, %r13d\n\
+	# And align stack for the _dl_init call.\n\
+	and $-16, %esp\n\
+	# _dl_loaded -> rdi\n\
+	movl _rtld_local(%rip), %edi\n\
+	# env -> rcx\n\
+	lea 8(%r13,%rdx,4), %ecx\n\
+	# argv -> rdx\n\
+	lea 4(%r13), %edx\n\
+	# Clear %rbp to mark outermost frame obviously even for constructors.\n\
+	xorl %ebp, %ebp\n\
+	# Call the function to run the initializers.\n\
+	call _dl_init\n\
+	# Pass our finalizer function to the user in %rdx, as per ELF ABI.\n\
+	lea _dl_fini(%rip), %edx\n\
+	# And make sure %rsp points to argc stored on the stack.\n\
+	movl %r13d, %esp\n\
+	# Jump to the user's entry point.\n\
+	jmp *%r12\n\
+.previous\n\
+");
+
+#endif /* !_X32_DL_MACHINE_H */