xref: /openbsd/lib/csu/i386/md_init.h (revision 510d2225)
1 /* $OpenBSD: md_init.h,v 1.13 2023/11/18 16:26:16 deraadt Exp $ */
2 
3 /*-
4  * Copyright (c) 2001 Ross Harvey
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *      This product includes software developed by the NetBSD
18  *      Foundation, Inc. and its contributors.
19  * 4. Neither the name of The NetBSD Foundation nor the names of its
20  *    contributors may be used to endorse or promote products derived
21  *    from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
24  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
25  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
26  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
27  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
30  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
31  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
33  * POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 #define MD_SECT_CALL_FUNC(section, func) \
37 	__asm (".section "#section", \"ax\"\n"	\
38 	"	call " #func "\n"		\
39 	"	.previous")
40 
41 #define MD_SECTION_PROLOGUE(sect, entry_pt)	\
42 	__asm (					\
43 	".section "#sect",\"ax\",@progbits	\n" \
44 	"	.globl " #entry_pt "		\n" \
45 	"	.type " #entry_pt ",@function	\n" \
46 	"	.align 16			\n" \
47 	#entry_pt":				\n" \
48 	"	pushl	%ebp			\n" \
49 	"	movl	%esp,%ebp		\n" \
50 	"	andl	$~15,%esp		\n" \
51 	"	.previous")
52 
53 
54 #define MD_SECTION_EPILOGUE(sect)		\
55 	__asm (					\
56 	".section "#sect",\"ax\",@progbits	\n" \
57 	"	leave				\n" \
58 	"	ret				\n" \
59 	"	.previous")
60 
61 
62 #define	MD_CRT0_START				\
63 	__asm(					\
64 	".text					\n" \
65 	"	.align	4			\n" \
66 	"	.globl	__start			\n" \
67 	"	.globl	_start			\n" \
68 	"_start:				\n" \
69 	"__start:				\n" \
70 	"	movl	%esp,%ebp		\n" \
71 	"	andl	$~15,%esp	# align stack\n" \
72 	"	pushl	%edx		# cleanup\n" \
73 	"	movl	0(%ebp),%eax		\n" \
74 	"	leal	8(%ebp,%eax,4),%ecx	\n" \
75 	"	leal	4(%ebp),%edx		\n" \
76 	"	pushl	%ecx			\n" \
77 	"	pushl	%edx			\n" \
78 	"	pushl	%eax			\n" \
79 	"	xorl	%ebp,%ebp	# mark deepest stack frame\n" \
80 	"	call	___start		\n" \
81 	"	.previous")
82 
83 #define	MD_RCRT0_START				\
84 	__asm(					\
85 	".text					\n" \
86 	"	.align	4			\n" \
87 	"	.globl	__start			\n" \
88 	"	.globl	_start			\n" \
89 	"_start:				\n" \
90 	"__start:				\n" \
91 	"	movl	%esp,%eax	# save SP for dl_boot_bind \n" \
92 	"	subl	$16*4,%esp 	# allocate dl_data \n" \
93 	"	call	1f		# push &_DYNAMIC... \n" \
94 	"1:	addl	$(_DYNAMIC-1b),(%esp)	# ...for dl_boot_bind \n" \
95 	"	movl	%esp,%ebx		\n" \
96 	"	pushl	%ebx		# push dl_data for dl_boot_bind \n" \
97 	"					\n" \
98 	"	mov	%eax, %esi	# save stack for ___start \n" \
99 	"	pushl	%eax		# push saved SP for dl_boot_bind \n" \
100 	"					\n" \
101 	"	call	_dl_boot_bind@PLT # _dl_boot_bind(sp,dl_data,0) \n" \
102 	"	addl	$3*4,%esp	# pop args \n" \
103 	"					\n" \
104 	"	movl	%esi,%ebp		\n" \
105 	"	andl	$~15,%esp	# align stack\n" \
106 	"	pushl	$0		# cleanup\n" \
107 	"	movl	0(%ebp),%eax	# argc	\n" \
108 	"	leal	8(%ebp,%eax,4),%ecx #envp \n" \
109 	"	leal	4(%ebp),%edx	# argv	\n" \
110 	"	pushl	%ecx			\n" \
111 	"	pushl	%edx			\n" \
112 	"	pushl	%eax			\n" \
113 	"	xorl	%ebp,%ebp	# mark deepest stack frame\n" \
114 	"	call	___start	# ___start(argc,argv,envp,0) \n" \
115 	"					\n" \
116 	"	.align	4			\n" \
117 	"	.globl	_csu_abort		\n" \
118 	"	.type	_csu_abort,@function	\n" \
119 	"_csu_abort:				\n" \
120 	"	int3				\n" \
121 	"	.previous")
122