1/* $NetBSD: asm.h,v 1.39.2.1 2026/04/02 19:12:03 martin Exp $ */
2
3/*-
4 * Copyright (c) 2014 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Matt Thomas of 3am Software Foundry.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32/*
33 * Copyright (c) 1990 The Regents of the University of California.
34 * All rights reserved.
35 *
36 * This code is derived from software contributed to Berkeley by
37 * William Jolitz.
38 *
39 * Redistribution and use in source and binary forms, with or without
40 * modification, are permitted provided that the following conditions
41 * are met:
42 * 1. Redistributions of source code must retain the above copyright
43 * notice, this list of conditions and the following disclaimer.
44 * 2. Redistributions in binary form must reproduce the above copyright
45 * notice, this list of conditions and the following disclaimer in the
46 * documentation and/or other materials provided with the distribution.
47 * 3. Neither the name of the University nor the names of its contributors
48 * may be used to endorse or promote products derived from this software
49 * without specific prior written permission.
50 *
51 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
52 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
53 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
54 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
55 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
56 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
57 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
58 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
59 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
60 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
61 * SUCH DAMAGE.
62 *
63 * from: @(#)asm.h 5.5 (Berkeley) 5/7/91
64 */
65
66#ifndef _ARM_ASM_H_
67#define _ARM_ASM_H_
68
69#include <arm/cdefs.h>
70#if defined(_KERNEL_OPT)
71#include "opt_cpuoptions.h"
72#endif
73
74#ifdef __thumb__
75#define THUMB_INSN(n) n
76#define _INSN_SIZE (2)
77#else
78#define THUMB_INSN(n)
79#define _INSN_SIZE (4)
80#endif
81
82#define __BIT(n) (1 << (n))
83#define __BITS(hi,lo) ((~((~0)<<((hi)+1)))&((~0)<<(lo)))
84
85#define __LOWEST_SET_BIT(__mask) ((((__mask) - 1) & (__mask)) ^ (__mask))
86#define __SHIFTOUT(__x, __mask) (((__x) & (__mask)) / __LOWEST_SET_BIT(__mask))
87#define __SHIFTIN(__x, __mask) ((__x) * __LOWEST_SET_BIT(__mask))
88
89#define _C_LABEL(x) x
90#define _ASM_LABEL(x) x
91
92#ifdef __STDC__
93# define __CONCAT(x,y) x ## y
94# define __STRING(x) #x
95#else
96# define __CONCAT(x,y) x/**/y
97# define __STRING(x) "x"
98#endif
99
100#ifndef _ALIGN_TEXT
101# define _ALIGN_TEXT .align 2
102#endif
103
104#ifndef _TEXT_SECTION
105#define _TEXT_SECTION .text
106#endif
107
108#ifdef __arm__
109
110 .syntax unified
111
112/*
113 * gas/arm uses @ as a single comment character and thus cannot be used here
114 * Instead it recognised the # instead of an @ symbols in .type directives
115 * We define a couple of macros so that assembly code will not be dependent
116 * on one or the other.
117 */
118#define _ASM_TYPE_FUNCTION %function
119#define _ASM_TYPE_OBJECT %object
120#define _THUMB_ENTRY(x) \
121 _TEXT_SECTION; _ALIGN_TEXT; .globl x; .type x,_ASM_TYPE_FUNCTION; \
122 .thumb_func; .code 16; x:
123#define _ARM_ENTRY(x) \
124 _TEXT_SECTION; _ALIGN_TEXT; .globl x; .type x,_ASM_TYPE_FUNCTION; \
125 .code 32; x:
126#ifdef __thumb__
127#define _ENTRY(x) _THUMB_ENTRY(x)
128#else
129#define _ENTRY(x) _ARM_ENTRY(x)
130#endif
131#define _END(x) .size x,.-x
132
133#ifdef GPROF
134# define _PROF_PROLOGUE \
135 push {lr}; bl __gnu_mcount_nc
136#else
137# define _PROF_PROLOGUE
138#endif
139#endif
140
141#ifdef __aarch64__
142#define _ASM_TYPE_FUNCTION @function
143#define _ASM_TYPE_OBJECT @object
144#define _ENTRY(x) \
145 _TEXT_SECTION; _ALIGN_TEXT; .globl x; .type x,_ASM_TYPE_FUNCTION; x:
146#define _END(x) .size x,.-x
147
148#ifdef GPROF
149# define _PROF_PROLOGUE \
150 stp x29, x30, [sp, #-16]!; \
151 mov fp, sp; \
152 bl __mcount; \
153 ldp x29, x30, [sp], #16;
154#else
155# define _PROF_PROLOGUE
156#endif
157
158#ifdef __PIC__
159#define GOTREF(x) :got:x
160#define GOTLO12(x) :got_lo12:x
161#else
162#define GOTREF(x) x
163#define GOTLO12(x) :lo12:x
164#endif
165#endif
166
167#ifdef ARMV85_BTI
168#define _BTI_PROLOGUE \
169 .byte 0x5F, 0x24, 0x03, 0xD5 /* the "bti c" instruction */
170#else
171#define _BTI_PROLOGUE /* nothing */
172#endif
173
174#define ENTRY(y) _ENTRY(_C_LABEL(y)); _BTI_PROLOGUE ; _PROF_PROLOGUE
175#define ENTRY_NP(y) _ENTRY(_C_LABEL(y)); _BTI_PROLOGUE
176#define ENTRY_NBTI(y) _ENTRY(_C_LABEL(y))
177#define END(y) _END(_C_LABEL(y))
178#define ARM_ENTRY(y) _ARM_ENTRY(_C_LABEL(y)); _PROF_PROLOGUE
179#define ARM_ENTRY_NP(y) _ARM_ENTRY(_C_LABEL(y))
180#define THUMB_ENTRY(y) _THUMB_ENTRY(_C_LABEL(y)); _PROF_PROLOGUE
181#define THUMB_ENTRY_NP(y) _THUMB_ENTRY(_C_LABEL(y))
182#define ASENTRY(y) _ENTRY(_ASM_LABEL(y)); _PROF_PROLOGUE
183#define ASENTRY_NP(y) _ENTRY(_ASM_LABEL(y))
184#define ASEND(y) _END(_ASM_LABEL(y))
185#define ARM_ASENTRY(y) _ARM_ENTRY(_ASM_LABEL(y)); _PROF_PROLOGUE
186#define ARM_ASENTRY_NP(y) _ARM_ENTRY(_ASM_LABEL(y))
187#define THUMB_ASENTRY(y) _THUMB_ENTRY(_ASM_LABEL(y)); _PROF_PROLOGUE
188#define THUMB_ASENTRY_NP(y) _THUMB_ENTRY(_ASM_LABEL(y))
189
190#define ASMSTR .asciz
191
192#ifdef __PIC__
193#define REL_SYM(a, b) ((a) - (b))
194#define PLT_SYM(x) x
195#define GOT_SYM(x) PIC_SYM(x, GOT)
196#define GOT_GET(x,got,sym) \
197 ldr x, sym; \
198 ldr x, [x, got]
199
200/*
201 * Load _GLOBAL_OFFSET_TABLE_ address into register:
202 *
203 * 0: GOT_INIT(rX, .Lgot)
204 * ...
205 *
206 * // and in the data after the function
207 * GOT_INITSYM(.Lgot, 0b)
208 */
209#define GOT_INIT(Rgot, gotsym) \
210 ldr Rgot, gotsym ; \
211 add Rgot, Rgot, pc
212#define GOT_INITSYM(gotsym, initlabel) \
213 .align 0; \
214 gotsym: .word _C_LABEL(_GLOBAL_OFFSET_TABLE_) - (initlabel+(1+2)*_INSN_SIZE)
215
216#ifdef __STDC__
217#define PIC_SYM(x,y) x(y)
218#else
219#define PIC_SYM(x,y) x/**/(/**/y/**/)
220#endif
221
222#else
223#define REL_SYM(a, b) (a)
224#define PLT_SYM(x) x
225#define GOT_SYM(x) x
226#define GOT_GET(x,got,sym) \
227 ldr x, sym;
228#define GOT_INIT(Rgot, gotsym)
229#define GOT_INITSYM(gotsym, initlabel)
230#define PIC_SYM(x,y) x
231#endif /* __PIC__ */
232
233/*
234 * Annoyingly, gas on arm seems to generate _two_ NUL-terminated
235 * strings for
236 *
237 * .asciz "foo" "bar"
238 *
239 * instead of concatenating it into a single NUL-terminated string as
240 * on other architectures.
241 *
242 * To work around this, we concatenate into a single NUL-terminated by:
243 *
244 * .ascii "foo"
245 * .asciz "bar"
246 */
247#define _IDENTSTR(x) .pushsection ".ident","MS",%progbits,1; \
248 x; \
249 .popsection
250
251#ifdef _NETBSD_REVISIONID
252#define RCSID(_s) \
253 _IDENTSTR(.asciz _s); \
254 _IDENTSTR(.ascii "$"; .ascii "NetBSD: "; .ascii __FILE__; \
255 .ascii " "; .ascii _NETBSD_REVISIONID; .asciz " $")
256#else
257#define RCSID(_s) _IDENTSTR(.asciz _s)
258#endif
259
260#define WEAK_ALIAS(alias,sym) \
261 .weak alias; \
262 alias = sym
263
264/*
265 * STRONG_ALIAS: create a strong alias.
266 */
267#define STRONG_ALIAS(alias,sym) \
268 .globl alias; \
269 alias = sym
270
271#ifdef __STDC__
272#define WARN_REFERENCES(sym,msg) \
273 .pushsection .gnu.warning.sym; \
274 .ascii msg; \
275 .popsection
276#else
277#define WARN_REFERENCES(sym,msg) \
278 .pushsection .gnu.warning./**/sym; \
279 .ascii msg; \
280 .popsection
281#endif /* __STDC__ */
282
283#ifdef __thumb__
284# define XPUSH push
285# define XPOP pop
286# define XPOPRET pop {pc}
287#else
288# define XPUSH stmfd sp!,
289# define XPOP ldmfd sp!,
290# ifdef _ARM_ARCH_5
291# define XPOPRET ldmfd sp!, {pc}
292# else
293# define XPOPRET ldmfd sp!, {lr}; mov pc, lr
294# endif
295#endif
296
297#if defined(__aarch64__)
298# define RET ret
299#elif defined (_ARM_ARCH_4T)
300# define RET bx lr
301# define RETr(r) bx r
302# if defined(__thumb__)
303# if defined(_ARM_ARCH_7)
304# define RETc(c) it c; __CONCAT(bx,c) lr
305# endif
306# else
307# define RETc(c) __CONCAT(bx,c) lr
308# endif
309#else
310# define RET mov pc, lr
311# define RETr(r) mov pc, r
312# define RETc(c) __CONCAT(mov,c) pc, lr
313#endif
314
315#ifdef _ARM_ARCH_7
316#define KMODTRAMPOLINE(n) \
317_ENTRY(__wrap_ ## n) \
318 movw ip, #:lower16:n; \
319 movt ip, #:upper16:n; \
320 bx ip
321#elif defined(_ARM_ARCH_4T)
322#define KMODTRAMPOLINE(n) \
323_ENTRY(__wrap_ ## n) \
324 ldr ip, [pc]; \
325 bx ip; \
326 .word n
327#else
328#define KMODTRAMPOLINE(n) \
329_ENTRY(__wrap_ ## n) \
330 ldr pc, [pc, #-4]; \
331 .word n
332#endif
333
334#endif /* !_ARM_ASM_H_ */