1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1993 The Regents of the University of California. 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. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * $FreeBSD$ 32 */ 33 34 #ifndef _MACHINE_ASMACROS_H_ 35 #define _MACHINE_ASMACROS_H_ 36 37 #include <sys/cdefs.h> 38 39 /* XXX too much duplication in various asm*.h's. */ 40 41 /* 42 * CNAME is used to manage the relationship between symbol names in C 43 * and the equivalent assembly language names. CNAME is given a name as 44 * it would be used in a C program. It expands to the equivalent assembly 45 * language name. 46 */ 47 #define CNAME(csym) csym 48 49 #define ALIGN_DATA .p2align 2 /* 4 byte alignment, zero filled */ 50 #ifdef GPROF 51 #define ALIGN_TEXT .p2align 4,0x90 /* 16-byte alignment, nop filled */ 52 #else 53 #define ALIGN_TEXT .p2align 2,0x90 /* 4-byte alignment, nop filled */ 54 #endif 55 #define SUPERALIGN_TEXT .p2align 4,0x90 /* 16-byte alignment, nop filled */ 56 57 #define GEN_ENTRY(name) ALIGN_TEXT; .globl CNAME(name); \ 58 .type CNAME(name),@function; CNAME(name): 59 #define NON_GPROF_ENTRY(name) GEN_ENTRY(name) 60 #define NON_GPROF_RET .byte 0xc3 /* opcode for `ret' */ 61 62 #define END(name) .size name, . - name 63 64 #ifdef GPROF 65 /* 66 * __mcount is like [.]mcount except that doesn't require its caller to set 67 * up a frame pointer. It must be called before pushing anything onto the 68 * stack. gcc should eventually generate code to call __mcount in most 69 * cases. This would make -pg in combination with -fomit-frame-pointer 70 * useful. gcc has a configuration variable PROFILE_BEFORE_PROLOGUE to 71 * allow profiling before setting up the frame pointer, but this is 72 * inadequate for good handling of special cases, e.g., -fpic works best 73 * with profiling after the prologue. 74 * 75 * [.]mexitcount is a new function to support non-statistical profiling if an 76 * accurate clock is available. For C sources, calls to it are generated 77 * by the FreeBSD extension `-mprofiler-epilogue' to gcc. It is best to 78 * call [.]mexitcount at the end of a function like the MEXITCOUNT macro does, 79 * but gcc currently generates calls to it at the start of the epilogue to 80 * avoid problems with -fpic. 81 * 82 * [.]mcount and __mcount may clobber the call-used registers and %ef. 83 * [.]mexitcount may clobber %ecx and %ef. 84 * 85 * Cross-jumping makes non-statistical profiling timing more complicated. 86 * It is handled in many cases by calling [.]mexitcount before jumping. It 87 * is handled for conditional jumps using CROSSJUMP() and CROSSJUMP_LABEL(). 88 * It is handled for some fault-handling jumps by not sharing the exit 89 * routine. 90 * 91 * ALTENTRY() must be before a corresponding ENTRY() so that it can jump to 92 * the main entry point. Note that alt entries are counted twice. They 93 * have to be counted as ordinary entries for gprof to get the call times 94 * right for the ordinary entries. 95 * 96 * High local labels are used in macros to avoid clashes with local labels 97 * in functions. 98 * 99 * Ordinary `ret' is used instead of a macro `RET' because there are a lot 100 * of `ret's. 0xc3 is the opcode for `ret' (`#define ret ... ret' can't 101 * be used because this file is sometimes preprocessed in traditional mode). 102 * `ret' clobbers eflags but this doesn't matter. 103 */ 104 #define ALTENTRY(name) GEN_ENTRY(name) ; MCOUNT ; MEXITCOUNT ; jmp 9f 105 #define CROSSJUMP(jtrue, label, jfalse) \ 106 jfalse 8f; MEXITCOUNT; jmp __CONCAT(to,label); 8: 107 #define CROSSJUMPTARGET(label) \ 108 ALIGN_TEXT; __CONCAT(to,label): ; MCOUNT; jmp label 109 #define ENTRY(name) GEN_ENTRY(name) ; 9: ; MCOUNT 110 #define FAKE_MCOUNT(caller) pushl caller ; call __mcount ; popl %ecx 111 #define MCOUNT call __mcount 112 #define MCOUNT_LABEL(name) GEN_ENTRY(name) ; nop ; ALIGN_TEXT 113 #ifdef GUPROF 114 #define MEXITCOUNT call .mexitcount 115 #define ret MEXITCOUNT ; NON_GPROF_RET 116 #else 117 #define MEXITCOUNT 118 #endif 119 120 #else /* !GPROF */ 121 /* 122 * ALTENTRY() has to align because it is before a corresponding ENTRY(). 123 * ENTRY() has to align to because there may be no ALTENTRY() before it. 124 * If there is a previous ALTENTRY() then the alignment code for ENTRY() 125 * is empty. 126 */ 127 #define ALTENTRY(name) GEN_ENTRY(name) 128 #define CROSSJUMP(jtrue, label, jfalse) jtrue label 129 #define CROSSJUMPTARGET(label) 130 #define ENTRY(name) GEN_ENTRY(name) 131 #define FAKE_MCOUNT(caller) 132 #define MCOUNT 133 #define MCOUNT_LABEL(name) 134 #define MEXITCOUNT 135 #endif /* GPROF */ 136 137 #ifdef LOCORE 138 /* 139 * Convenience macro for declaring interrupt entry points. 140 */ 141 #define IDTVEC(name) ALIGN_TEXT; .globl __CONCAT(X,name); \ 142 .type __CONCAT(X,name),@function; __CONCAT(X,name): 143 144 /* 145 * Macros to create and destroy a trap frame. 146 */ 147 #define PUSH_FRAME \ 148 pushl $0 ; /* dummy error code */ \ 149 pushl $0 ; /* dummy trap type */ \ 150 pushal ; /* 8 ints */ \ 151 pushl $0 ; /* save data and extra segments ... */ \ 152 movw %ds,(%esp) ; \ 153 pushl $0 ; \ 154 movw %es,(%esp) ; \ 155 pushl $0 ; \ 156 movw %fs,(%esp) 157 158 /* 159 * Access per-CPU data. 160 */ 161 #define PCPU(member) %fs:PC_ ## member 162 163 #define PCPU_ADDR(member, reg) \ 164 movl %fs:PC_PRVSPACE, reg ; \ 165 addl $PC_ ## member, reg 166 167 /* 168 * Setup the kernel segment registers. 169 */ 170 #define SET_KERNEL_SREGS \ 171 movl $KDSEL, %eax ; /* reload with kernel's data segment */ \ 172 movl %eax, %ds ; \ 173 movl %eax, %es ; \ 174 movl $KPSEL, %eax ; /* reload with per-CPU data segment */ \ 175 movl %eax, %fs 176 177 #endif /* LOCORE */ 178 179 #ifdef __STDC__ 180 #define ELFNOTE(name, type, desctype, descdata...) \ 181 .pushsection .note.name ; \ 182 .align 4 ; \ 183 .long 2f - 1f /* namesz */ ; \ 184 .long 4f - 3f /* descsz */ ; \ 185 .long type ; \ 186 1:.asciz #name ; \ 187 2:.align 4 ; \ 188 3:desctype descdata ; \ 189 4:.align 4 ; \ 190 .popsection 191 #else /* !__STDC__, i.e. -traditional */ 192 #define ELFNOTE(name, type, desctype, descdata) \ 193 .pushsection .note.name ; \ 194 .align 4 ; \ 195 .long 2f - 1f /* namesz */ ; \ 196 .long 4f - 3f /* descsz */ ; \ 197 .long type ; \ 198 1:.asciz "name" ; \ 199 2:.align 4 ; \ 200 3:desctype descdata ; \ 201 4:.align 4 ; \ 202 .popsection 203 #endif /* __STDC__ */ 204 205 #endif /* !_MACHINE_ASMACROS_H_ */ 206