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 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * $Id$ 34 */ 35 36 #ifndef _MACHINE_ASMACROS_H_ 37 #define _MACHINE_ASMACROS_H_ 38 39 #ifdef KERNEL 40 #include <sys/cdefs.h> 41 42 /* XXX too much duplication in various asm*.h's. */ 43 44 #define ALIGN_DATA .align 2 /* 4 byte alignment, zero filled */ 45 #ifdef GPROF 46 #define ALIGN_TEXT .align 4,0x90 /* 16-byte alignment, nop filled */ 47 #else 48 #define ALIGN_TEXT .align 2,0x90 /* 4-byte alignment, nop filled */ 49 #endif 50 #define SUPERALIGN_TEXT .align 4,0x90 /* 16-byte alignment, nop filled */ 51 52 #define GEN_ENTRY(name) ALIGN_TEXT; .globl __CONCAT(_,name); \ 53 __CONCAT(_,name): 54 #define NON_GPROF_ENTRY(name) GEN_ENTRY(name) 55 #define NON_GPROF_RET .byte 0xc3 /* opcode for `ret' */ 56 57 #ifdef GPROF 58 /* 59 * __mcount is like mcount except that doesn't require its caller to set 60 * up a frame pointer. It must be called before pushing anything onto the 61 * stack. gcc should eventually generate code to call __mcount in most 62 * cases. This would make -pg in combination with -fomit-frame-pointer 63 * useful. gcc has a configuration variable PROFILE_BEFORE_PROLOGUE to 64 * allow profiling before setting up the frame pointer, but this is 65 * inadequate for good handling of special cases, e.g., -fpic works best 66 * with profiling after the prologue. 67 * 68 * mexitcount is a new function to support non-statistical profiling if an 69 * accurate clock is available. For C sources, calls to it are generated 70 * by the FreeBSD extension `-mprofiler-epilogue' to gcc. It is best to 71 * call mexitcount at the end of a function like the MEXITCOUNT macro does, 72 * but gcc currently generates calls to it at the start of the epilogue to 73 * avoid problems with -fpic. 74 * 75 * mcount and __mexitcount may clobber the call-used registers and %ef. 76 * mexitcount may clobber %ecx and %ef. 77 * 78 * Cross-jumping makes non-statistical profiling timing more complicated. 79 * It is handled in many cases by calling mexitcount before jumping. It is 80 * handled for conditional jumps using CROSSJUMP() and CROSSJUMP_LABEL(). 81 * It is handled for some fault-handling jumps by not sharing the exit 82 * routine. 83 * 84 * ALTENTRY() must be before a corresponding ENTRY() so that it can jump to 85 * the main entry point. Note that alt entries are counted twice. They 86 * have to be counted as ordinary entries for gprof to get the call times 87 * right for the ordinary entries. 88 * 89 * High local labels are used in macros to avoid clashes with local labels 90 * in functions. 91 * 92 * Ordinary `ret' is used instead of a macro `RET' because there are a lot 93 * of `ret's. 0xc3 is the opcode for `ret' (`#define ret ... ret' can't 94 * be used because this file is sometimes preprocessed in traditional mode). 95 * `ret' clobbers eflags but this doesn't matter. 96 */ 97 #define ALTENTRY(name) GEN_ENTRY(name) ; MCOUNT ; MEXITCOUNT ; jmp 9f 98 #define CROSSJUMP(jtrue, label, jfalse) \ 99 jfalse 8f; MEXITCOUNT; jmp __CONCAT(to,label); 8: 100 #define CROSSJUMPTARGET(label) \ 101 ALIGN_TEXT; __CONCAT(to,label): ; MCOUNT; jmp label 102 #define ENTRY(name) GEN_ENTRY(name) ; 9: ; MCOUNT 103 #define FAKE_MCOUNT(caller) pushl caller ; call __mcount ; popl %ecx 104 #define MCOUNT call __mcount 105 #define MCOUNT_LABEL(name) GEN_ENTRY(name) ; nop ; ALIGN_TEXT 106 #define MEXITCOUNT call mexitcount 107 #define ret MEXITCOUNT ; NON_GPROF_RET 108 109 #else /* !GPROF */ 110 /* 111 * ALTENTRY() has to align because it is before a corresponding ENTRY(). 112 * ENTRY() has to align to because there may be no ALTENTRY() before it. 113 * If there is a previous ALTENTRY() then the alignment code for ENTRY() 114 * is empty. 115 */ 116 #define ALTENTRY(name) GEN_ENTRY(name) 117 #define CROSSJUMP(jtrue, label, jfalse) jtrue label 118 #define CROSSJUMPTARGET(label) 119 #define ENTRY(name) GEN_ENTRY(name) 120 #define FAKE_MCOUNT(caller) 121 #define MCOUNT 122 #define MCOUNT_LABEL(name) 123 #define MEXITCOUNT 124 #endif /* GPROF */ 125 126 #else /* !KERNEL */ 127 128 #include "/usr/src/lib/libc/i386/DEFS.h" /* XXX blech */ 129 130 /* 131 * In the !KERNEL case, this header is only (ab)used in lib/msun/i387. 132 * Use it to generate code to select between the generic math functions 133 * and the i387 ones. 134 */ 135 #undef ENTRY 136 #define ANAME(x) CNAME(__CONCAT(__i387_,x)) 137 #define ASELNAME(x) CNAME(__CONCAT(__arch_select_,x)) 138 #define AVECNAME(x) CNAME(__CONCAT(__arch_,x)) 139 #define GNAME(x) CNAME(__CONCAT(__generic_,x)) 140 141 /* Don't bother profiling this. */ 142 #ifdef PIC 143 #define ARCH_DISPATCH(x) \ 144 _START_ENTRY; \ 145 .globl CNAME(x); .type CNAME(x),@function; CNAME(x): ; \ 146 PIC_PROLOGUE; \ 147 movl PIC_GOT(AVECNAME(x)),%eax; \ 148 PIC_EPILOGUE; \ 149 jmpl *(%eax) 150 151 #define ARCH_SELECT(x) _START_ENTRY; \ 152 .type ASELNAME(x),@function; \ 153 ASELNAME(x): \ 154 PIC_PROLOGUE; \ 155 call PIC_PLT(CNAME(__get_hw_float)); \ 156 testl %eax,%eax; \ 157 movl PIC_GOT(ANAME(x)),%eax; \ 158 jne 8f; \ 159 movl PIC_GOT(GNAME(x)),%eax; \ 160 8: \ 161 movl PIC_GOT(AVECNAME(x)),%edx; \ 162 movl %eax,(%edx); \ 163 PIC_EPILOGUE; \ 164 jmpl *%eax 165 #else /* !PIC */ 166 #define ARCH_DISPATCH(x) \ 167 _START_ENTRY; \ 168 .globl CNAME(x); .type CNAME(x),@function; CNAME(x): ; \ 169 jmpl *AVECNAME(x) 170 171 #define ARCH_SELECT(x) _START_ENTRY; \ 172 .type ASELNAME(x),@function; \ 173 ASELNAME(x): \ 174 call CNAME(__get_hw_float); \ 175 testl %eax,%eax; \ 176 movl $ANAME(x),%eax; \ 177 jne 8f; \ 178 movl $GNAME(x),%eax; \ 179 8: \ 180 movl %eax,AVECNAME(x); \ 181 jmpl *%eax 182 #endif /* PIC */ 183 184 #define ARCH_VECTOR(x) .data; .align 2; \ 185 .globl AVECNAME(x); \ 186 .type AVECNAME(x),@object; \ 187 .size AVECNAME(x),4; \ 188 AVECNAME(x): .long ASELNAME(x) 189 190 #ifdef PROF 191 192 #define ALTENTRY(x) ENTRY(x); jmp 9f 193 #define ENTRY(x) ARCH_VECTOR(x); ARCH_SELECT(x); ARCH_DISPATCH(x); \ 194 _START_ENTRY; \ 195 .globl ANAME(x); .type ANAME(x),@function; ANAME(x):; \ 196 call HIDENAME(mcount); 9: 197 198 #else /* !PROF */ 199 200 #define ALTENTRY(x) ENTRY(x) 201 #define ENTRY(x) ARCH_VECTOR(x); ARCH_SELECT(x); ARCH_DISPATCH(x); \ 202 _START_ENTRY; \ 203 .globl ANAME(x); .type ANAME(x),@function; ANAME(x): 204 205 #endif /* PROF */ 206 207 #ifndef RCSID 208 #define RCSID(a) 209 #endif 210 211 #endif /* KERNEL */ 212 213 #endif /* !_MACHINE_ASMACROS_H_ */ 214