1 /*- 2 * Copyright (c) 1993 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD$ 30 */ 31 32 #ifndef _MACHINE_ASMACROS_H_ 33 #define _MACHINE_ASMACROS_H_ 34 35 #include <sys/cdefs.h> 36 37 /* XXX too much duplication in various asm*.h's. */ 38 39 /* 40 * CNAME is used to manage the relationship between symbol names in C 41 * and the equivalent assembly language names. CNAME is given a name as 42 * it would be used in a C program. It expands to the equivalent assembly 43 * language name. 44 */ 45 #define CNAME(csym) csym 46 47 #define ALIGN_DATA .p2align 2 /* 4 byte alignment, zero filled */ 48 #ifdef GPROF 49 #define ALIGN_TEXT .p2align 4,0x90 /* 16-byte alignment, nop filled */ 50 #else 51 #define ALIGN_TEXT .p2align 2,0x90 /* 4-byte alignment, nop filled */ 52 #endif 53 #define SUPERALIGN_TEXT .p2align 4,0x90 /* 16-byte alignment, nop filled */ 54 55 #define GEN_ENTRY(name) ALIGN_TEXT; .globl CNAME(name); \ 56 .type CNAME(name),@function; CNAME(name): 57 #define NON_GPROF_ENTRY(name) GEN_ENTRY(name) 58 #define NON_GPROF_RET .byte 0xc3 /* opcode for `ret' */ 59 60 #define END(name) .size name, . - name 61 62 #ifdef GPROF 63 /* 64 * __mcount is like [.]mcount except that doesn't require its caller to set 65 * up a frame pointer. It must be called before pushing anything onto the 66 * stack. gcc should eventually generate code to call __mcount in most 67 * cases. This would make -pg in combination with -fomit-frame-pointer 68 * useful. gcc has a configuration variable PROFILE_BEFORE_PROLOGUE to 69 * allow profiling before setting up the frame pointer, but this is 70 * inadequate for good handling of special cases, e.g., -fpic works best 71 * with profiling after the prologue. 72 * 73 * [.]mexitcount is a new function to support non-statistical profiling if an 74 * accurate clock is available. For C sources, calls to it are generated 75 * by the FreeBSD extension `-mprofiler-epilogue' to gcc. It is best to 76 * call [.]mexitcount at the end of a function like the MEXITCOUNT macro does, 77 * but gcc currently generates calls to it at the start of the epilogue to 78 * avoid problems with -fpic. 79 * 80 * [.]mcount and __mcount may clobber the call-used registers and %ef. 81 * [.]mexitcount may clobber %ecx and %ef. 82 * 83 * Cross-jumping makes non-statistical profiling timing more complicated. 84 * It is handled in many cases by calling [.]mexitcount before jumping. It 85 * is handled for conditional jumps using CROSSJUMP() and CROSSJUMP_LABEL(). 86 * It is handled for some fault-handling jumps by not sharing the exit 87 * routine. 88 * 89 * ALTENTRY() must be before a corresponding ENTRY() so that it can jump to 90 * the main entry point. Note that alt entries are counted twice. They 91 * have to be counted as ordinary entries for gprof to get the call times 92 * right for the ordinary entries. 93 * 94 * High local labels are used in macros to avoid clashes with local labels 95 * in functions. 96 * 97 * Ordinary `ret' is used instead of a macro `RET' because there are a lot 98 * of `ret's. 0xc3 is the opcode for `ret' (`#define ret ... ret' can't 99 * be used because this file is sometimes preprocessed in traditional mode). 100 * `ret' clobbers eflags but this doesn't matter. 101 */ 102 #define ALTENTRY(name) GEN_ENTRY(name) ; MCOUNT ; MEXITCOUNT ; jmp 9f 103 #define CROSSJUMP(jtrue, label, jfalse) \ 104 jfalse 8f; MEXITCOUNT; jmp __CONCAT(to,label); 8: 105 #define CROSSJUMPTARGET(label) \ 106 ALIGN_TEXT; __CONCAT(to,label): ; MCOUNT; jmp label 107 #define ENTRY(name) GEN_ENTRY(name) ; 9: ; MCOUNT 108 #define FAKE_MCOUNT(caller) pushl caller ; call __mcount ; popl %ecx 109 #define MCOUNT call __mcount 110 #define MCOUNT_LABEL(name) GEN_ENTRY(name) ; nop ; ALIGN_TEXT 111 #ifdef GUPROF 112 #define MEXITCOUNT call .mexitcount 113 #define ret MEXITCOUNT ; NON_GPROF_RET 114 #else 115 #define MEXITCOUNT 116 #endif 117 118 #else /* !GPROF */ 119 /* 120 * ALTENTRY() has to align because it is before a corresponding ENTRY(). 121 * ENTRY() has to align to because there may be no ALTENTRY() before it. 122 * If there is a previous ALTENTRY() then the alignment code for ENTRY() 123 * is empty. 124 */ 125 #define ALTENTRY(name) GEN_ENTRY(name) 126 #define CROSSJUMP(jtrue, label, jfalse) jtrue label 127 #define CROSSJUMPTARGET(label) 128 #define ENTRY(name) GEN_ENTRY(name) 129 #define FAKE_MCOUNT(caller) 130 #define MCOUNT 131 #define MCOUNT_LABEL(name) 132 #define MEXITCOUNT 133 #endif /* GPROF */ 134 135 #ifdef LOCORE 136 /* 137 * Convenience macro for declaring interrupt entry points. 138 */ 139 #define IDTVEC(name) ALIGN_TEXT; .globl __CONCAT(X,name); \ 140 .type __CONCAT(X,name),@function; __CONCAT(X,name): 141 142 /* 143 * Macros to create and destroy a trap frame. 144 */ 145 #define PUSH_FRAME \ 146 pushl $0 ; /* dummy error code */ \ 147 pushl $0 ; /* dummy trap type */ \ 148 pushal ; /* 8 ints */ \ 149 pushl %ds ; /* save data and extra segments ... */ \ 150 pushl %es ; \ 151 pushl %fs 152 153 #define POP_FRAME \ 154 popl %fs ; \ 155 popl %es ; \ 156 popl %ds ; \ 157 popal ; \ 158 addl $4+4,%esp 159 160 /* 161 * Access per-CPU data. 162 */ 163 #define PCPU(member) %fs:PC_ ## member 164 165 #define PCPU_ADDR(member, reg) \ 166 movl %fs:PC_PRVSPACE, reg ; \ 167 addl $PC_ ## member, reg 168 169 /* 170 * Setup the kernel segment registers. 171 */ 172 #define SET_KERNEL_SREGS \ 173 movl $KDSEL, %eax ; /* reload with kernel's data segment */ \ 174 movl %eax, %ds ; \ 175 movl %eax, %es ; \ 176 movl $KPSEL, %eax ; /* reload with per-CPU data segment */ \ 177 movl %eax, %fs 178 179 #endif /* LOCORE */ 180 181 #endif /* !_MACHINE_ASMACROS_H_ */ 182