1 /* -*- mode: asm -*- */
3 * SPDX-License-Identifier: BSD-3-Clause
5 * Copyright (c) 1993 The Regents of the University of California.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 #ifndef _MACHINE_ASMACROS_H_
36 #define _MACHINE_ASMACROS_H_
38 #include <sys/cdefs.h>
40 /* XXX too much duplication in various asm*.h's. */
43 * CNAME is used to manage the relationship between symbol names in C
44 * and the equivalent assembly language names. CNAME is given a name as
45 * it would be used in a C program. It expands to the equivalent assembly
48 #define CNAME(csym) csym
50 #define ALIGN_DATA .p2align 2 /* 4 byte alignment, zero filled */
52 #define ALIGN_TEXT .p2align 4,0x90 /* 16-byte alignment, nop filled */
54 #define ALIGN_TEXT .p2align 2,0x90 /* 4-byte alignment, nop filled */
56 #define SUPERALIGN_TEXT .p2align 4,0x90 /* 16-byte alignment, nop filled */
58 #define GEN_ENTRY(name) ALIGN_TEXT; .globl CNAME(name); \
59 .type CNAME(name),@function; CNAME(name):
60 #define NON_GPROF_ENTRY(name) GEN_ENTRY(name)
61 #define NON_GPROF_RET .byte 0xc3 /* opcode for `ret' */
63 #define END(name) .size name, . - name
67 * __mcount is like [.]mcount except that doesn't require its caller to set
68 * up a frame pointer. It must be called before pushing anything onto the
69 * stack. gcc should eventually generate code to call __mcount in most
70 * cases. This would make -pg in combination with -fomit-frame-pointer
71 * useful. gcc has a configuration variable PROFILE_BEFORE_PROLOGUE to
72 * allow profiling before setting up the frame pointer, but this is
73 * inadequate for good handling of special cases, e.g., -fpic works best
74 * with profiling after the prologue.
76 * [.]mexitcount is a new function to support non-statistical profiling if an
77 * accurate clock is available. For C sources, calls to it are generated
78 * by the FreeBSD extension `-mprofiler-epilogue' to gcc. It is best to
79 * call [.]mexitcount at the end of a function like the MEXITCOUNT macro does,
80 * but gcc currently generates calls to it at the start of the epilogue to
81 * avoid problems with -fpic.
83 * [.]mcount and __mcount may clobber the call-used registers and %ef.
84 * [.]mexitcount may clobber %ecx and %ef.
86 * Cross-jumping makes non-statistical profiling timing more complicated.
87 * It is handled in many cases by calling [.]mexitcount before jumping. It
88 * is handled for conditional jumps using CROSSJUMP() and CROSSJUMP_LABEL().
89 * It is handled for some fault-handling jumps by not sharing the exit
92 * ALTENTRY() must be before a corresponding ENTRY() so that it can jump to
93 * the main entry point. Note that alt entries are counted twice. They
94 * have to be counted as ordinary entries for gprof to get the call times
95 * right for the ordinary entries.
97 * High local labels are used in macros to avoid clashes with local labels
100 * Ordinary `ret' is used instead of a macro `RET' because there are a lot
101 * of `ret's. 0xc3 is the opcode for `ret' (`#define ret ... ret' can't
102 * be used because this file is sometimes preprocessed in traditional mode).
103 * `ret' clobbers eflags but this doesn't matter.
105 #define ALTENTRY(name) GEN_ENTRY(name) ; MCOUNT ; MEXITCOUNT ; jmp 9f
106 #define CROSSJUMP(jtrue, label, jfalse) \
107 jfalse 8f; MEXITCOUNT; jmp __CONCAT(to,label); 8:
108 #define CROSSJUMPTARGET(label) \
109 ALIGN_TEXT; __CONCAT(to,label): ; MCOUNT; jmp label
110 #define ENTRY(name) GEN_ENTRY(name) ; 9: ; MCOUNT
111 #define FAKE_MCOUNT(caller) pushl caller ; call *__mcountp ; popl %ecx
112 #define MCOUNT call *__mcountp
113 #define MCOUNT_LABEL(name) GEN_ENTRY(name) ; nop ; ALIGN_TEXT
115 #define MEXITCOUNT call *__mexitcountp
116 #define ret MEXITCOUNT ; NON_GPROF_RET
123 * ALTENTRY() has to align because it is before a corresponding ENTRY().
124 * ENTRY() has to align to because there may be no ALTENTRY() before it.
125 * If there is a previous ALTENTRY() then the alignment code for ENTRY()
128 #define ALTENTRY(name) GEN_ENTRY(name)
129 #define CROSSJUMP(jtrue, label, jfalse) jtrue label
130 #define CROSSJUMPTARGET(label)
131 #define ENTRY(name) GEN_ENTRY(name)
132 #define FAKE_MCOUNT(caller)
134 #define MCOUNT_LABEL(name)
140 #define GSEL_KPL 0x0020 /* GSEL(GCODE_SEL, SEL_KPL) */
141 #define SEL_RPL_MASK 0x0003
144 * Convenience macro for declaring interrupt entry points.
146 #define IDTVEC(name) ALIGN_TEXT; .globl __CONCAT(X,name); \
147 .type __CONCAT(X,name),@function; __CONCAT(X,name):
150 * Macros to create and destroy a trap frame.
163 pushl $0 /* dummy error code */
164 pushl $0 /* dummy trap type */
169 * Access per-CPU data.
171 #define PCPU(member) %fs:PC_ ## member
173 #define PCPU_ADDR(member, reg) \
174 movl %fs:PC_PRVSPACE, reg ; \
175 addl $PC_ ## member, reg
178 * Setup the kernel segment registers.
180 .macro SET_KERNEL_SREGS
181 movl $KDSEL, %eax /* reload with kernel's data segment */
184 movl $KPSEL, %eax /* reload with per-CPU data segment */
189 movl PCPU(KESP0), %edx
191 testl $PSL_VM, TF_EFLAGS(%esp)
193 addl $VM86_STACK_SPACE, %ecx
194 .L\@.1: subl %ecx, %edx
204 movl (tramp_idleptd - .L\@.1)(%eax), %eax
214 testl $PSL_VM, TF_EFLAGS(%esp)
217 movl PCPU(CURPCB), %eax
218 testl $PCB_VM86CALL, PCB_FLAGS(%eax)
221 movl $handle_ibrs_entry,%edx
224 .L\@.1: testb $SEL_RPL_MASK, TF_CS(%esp)
227 movl $handle_ibrs_entry,%edx
235 #define ELFNOTE(name, type, desctype, descdata...) \
236 .pushsection .note.name ; \
238 .long 2f - 1f /* namesz */ ; \
239 .long 4f - 3f /* descsz */ ; \
243 3:desctype descdata ; \
246 #else /* !__STDC__, i.e. -traditional */
247 #define ELFNOTE(name, type, desctype, descdata) \
248 .pushsection .note.name ; \
250 .long 2f - 1f /* namesz */ ; \
251 .long 4f - 3f /* descsz */ ; \
255 3:desctype descdata ; \
258 #endif /* __STDC__ */
260 #endif /* !_MACHINE_ASMACROS_H_ */