EXTERNAL_HEADERS/architecture/i386/asm_help.h

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /* Copyright (c) 1991 NeXT Computer, Inc.  All rights reserved.
  29  *
  30  *      File:   architecture/i386/asm_help.h
  31  *      Author: Mike DeMoney, NeXT Computer, Inc.
  32  *      Modified for i386 by: Bruce Martin, NeXT Computer, Inc.
  33  *
  34  *      This header file defines macros useful when writing assembly code
  35  *      for the Intel i386 family processors.
  36  *
  37  * HISTORY
  38  * 10-Mar-92  Bruce Martin (bmartin@next.com)
  39  *      Adapted to i386
  40  * 23-Jan-91  Mike DeMoney (mike@next.com)
  41  *      Created.
  42  */
  43
  44 #ifndef _ARCH_I386_ASM_HELP_H_
  45 #define _ARCH_I386_ASM_HELP_H_
  46
  47 #include        <architecture/i386/reg_help.h>
  48
  49
  50 #ifdef  __ASSEMBLER__
  51
  52 #define ALIGN                                           \
  53         .align  2, 0x90
  54
  55 /* Note that ROUND_TO_STACK rounds to Intel's stack alignment requirement,
  56  * but it is not sufficient for the Apple ABI which requires a 16-byte
  57  * aligned stack.  Various parts of the OS depend on this requirement,
  58  * including dyld.
  59  */
  60 #define ROUND_TO_STACK(len)                             \
  61         (((len) + STACK_INCR - 1) / STACK_INCR * STACK_INCR)
  62
  63 #ifdef notdef
  64 #define CALL_MCOUNT                                             \
  65         pushl   %ebp                                            ;\
  66         movl    %esp, %ebp                                      ;\
  67         .data                                                   ;\
  68         1: .long 0                                              ;\
  69         .text                                                   ;\
  70         lea 9b,%edx                                             ;\
  71         call mcount                                             ;\
  72         popl    %ebp                                            ;
  73 #else
  74 #define CALL_MCOUNT
  75 #endif
  76
  77 /*
  78  * Prologue for functions that may call other functions.  Saves
  79  * registers and sets up a C frame.
  80  */
  81 #define NESTED_FUNCTION_PROLOGUE(localvarsize)                  \
  82         .set    __framesize,ROUND_TO_STACK(localvarsize)        ;\
  83         .set    __nested_function, 1                            ;\
  84         CALL_MCOUNT                                             \
  85         .if __framesize                                         ;\
  86           pushl %ebp                                            ;\
  87           movl  %esp, %ebp                                      ;\
  88           subl  $__framesize, %esp                              ;\
  89         .endif                                                  ;\
  90         pushl   %edi                                            ;\
  91         pushl   %esi                                            ;\
  92         pushl   %ebx
  93
  94 /*
  95  * Prologue for functions that do not call other functions.  Does not
  96  * save registers (this is the functions responsibility).  Does set
  97  * up a C frame.
  98  */
  99 #define LEAF_FUNCTION_PROLOGUE(localvarsize)                    \
 100         .set    __framesize,ROUND_TO_STACK(localvarsize)        ;\
 101         .set    __nested_function, 0                            ;\
 102         CALL_MCOUNT                                             \
 103         .if __framesize                                         ;\
 104           pushl %ebp                                            ;\
 105           movl  %esp, %ebp                                      ;\
 106           subl  $__framesize, %esp                              ;\
 107         .endif
 108
 109 /*
 110  * Prologue for any function.
 111  *
 112  * We assume that all Leaf functions will be responsible for saving any
 113  * local registers they clobber.
 114  */
 115 #define FUNCTION_EPILOGUE                                       \
 116         .if __nested_function                                   ;\
 117           popl  %ebx                                            ;\
 118           popl  %esi                                            ;\
 119           popl  %edi                                            ;\
 120         .endif                                                  ;\
 121         .if __framesize                                         ;\
 122           movl  %ebp, %esp                                      ;\
 123           popl  %ebp                                            ;\
 124         .endif                                                  ;\
 125         ret
 126
 127
 128 /*
 129  * Macros for declaring procedures
 130  *
 131  * Use of these macros allows ctags to have a predictable way
 132  * to find various types of declarations.  They also simplify
 133  * inserting appropriate symbol table information.
 134  *
 135  * NOTE: these simple stubs will be replaced with more
 136  * complicated versions once we know what the linker and gdb
 137  * will require as far as register use masks and frame declarations.
 138  * These macros may also be ifdef'ed in the future to contain profiling
 139  * code.
 140  *
 141  */
 142
 143 /*
 144  * TEXT -- declare start of text segment
 145  */
 146 #define TEXT                                            \
 147         .text
 148
 149 /*
 150  * DATA -- declare start of data segment
 151  */
 152 #define DATA                                            \
 153         .data
 154
 155 /*
 156  * LEAF -- declare global leaf procedure
 157  * NOTE: Control SHOULD NOT FLOW into a LEAF!  A LEAF should only
 158  * be jumped to.  (A leaf may do an align.)  Use a LABEL() if you
 159  * need control to flow into the label.
 160  */
 161 #define LEAF(name, localvarsize)                        \
 162         .globl  name                                    ;\
 163         ALIGN                                           ;\
 164 name:                                                   ;\
 165         LEAF_FUNCTION_PROLOGUE(localvarsize)
 166
 167 /*
 168  * X_LEAF -- declare alternate global label for leaf
 169  */
 170 #define X_LEAF(name, value)                             \
 171         .globl  name                                    ;\
 172         .set    name,value
 173
 174 /*
 175  * P_LEAF -- declare private leaf procedure
 176  */
 177 #define P_LEAF(name, localvarsize)                      \
 178         ALIGN                                           ;\
 179 name:                                                   ;\
 180         LEAF_FUNCTION_PROLOGUE(localvarsize)
 181
 182 /*
 183  * LABEL -- declare a global code label
 184  * MUST be used (rather than LEAF, NESTED, etc) if control
 185  * "flows into" the label.
 186  */
 187 #define LABEL(name)                                     \
 188         .globl  name                                    ;\
 189 name:
 190
 191 /*
 192  * NESTED -- declare procedure that invokes other procedures
 193  */
 194 #define NESTED(name, localvarsize)                      \
 195         .globl  name                                    ;\
 196         ALIGN                                           ;\
 197 name:                                                   ;\
 198         NESTED_FUNCTION_PROLOGUE(localvarsize)
 199
 200 /*
 201  * X_NESTED -- declare alternate global label for nested proc
 202  */
 203 #define X_NESTED(name, value)                           \
 204         .globl  name                                    ;\
 205         .set    name,value
 206
 207 /*
 208  * P_NESTED -- declare private nested procedure
 209  */
 210 #define P_NESTED(name, localvarsize)                    \
 211         ALIGN                                           ;\
 212 name:                                                   ;\
 213         NESTED_FUNCTION_PROLOGUE(localvarsize)
 214
 215 /*
 216  * END -- mark end of procedure
 217  */
 218 #define END(name)                                       \
 219         FUNCTION_EPILOGUE
 220
 221
 222 /*
 223  * Storage definition macros
 224  * The main purpose of these is to allow an easy handle for ctags
 225  */
 226
 227 /*
 228  * IMPORT -- import symbol
 229  */
 230 #define IMPORT(name)                                    \
 231         .reference      name
 232
 233 /*
 234  * ABS -- declare global absolute symbol
 235  */
 236 #define ABS(name, value)                                \
 237         .globl  name                                    ;\
 238         .set    name,value
 239
 240 /*
 241  * P_ABS -- declare private absolute symbol
 242  */
 243 #define P_ABS(name, value)                              \
 244         .set    name,value
 245
 246 /*
 247  * EXPORT -- declare global label for data
 248  */
 249 #define EXPORT(name)                                    \
 250         .globl  name                                    ;\
 251 name:
 252
 253 /*
 254  * BSS -- declare global zero'ed storage
 255  */
 256 #define BSS(name,size)                                  \
 257         .comm   name,size
 258
 259
 260 /*
 261  * P_BSS -- declare private zero'ed storage
 262  */
 263 #define P_BSS(name,size)                                \
 264         .lcomm  name,size
 265
 266 /*
 267  * dynamic/PIC macros for routines which reference external symbols
 268  */
 269
 270 #if defined(__DYNAMIC__)
 271 #define PICIFY(var)                                     \
 272         call    1f                                      ; \
 273 1:                                                      ; \
 274         popl    %edx                                    ; \
 275         movl    L ## var ## $non_lazy_ptr-1b(%edx),%edx
 276
 277 #define CALL_EXTERN_AGAIN(func) \
 278         PICIFY(func)            ; \
 279         call    %edx
 280
 281 #define NON_LAZY_STUB(var)      \
 282 .non_lazy_symbol_pointer        ; \
 283 L ## var ## $non_lazy_ptr:      ; \
 284 .indirect_symbol var            ; \
 285 .long 0                         ; \
 286 .text
 287
 288 #define CALL_EXTERN(func)       \
 289         CALL_EXTERN_AGAIN(func) ; \
 290         NON_LAZY_STUB(func)
 291
 292 #define BRANCH_EXTERN(func)     \
 293         PICIFY(func)            ; \
 294         jmp     %edx            ; \
 295         NON_LAZY_STUB(func)
 296
 297 #define PUSH_EXTERN(var)        \
 298         PICIFY(var)             ; \
 299         movl    (%edx),%edx     ; \
 300         pushl   %edx            ; \
 301         NON_LAZY_STUB(var)
 302
 303 #define REG_TO_EXTERN(reg, var) \
 304         PICIFY(var)             ; \
 305         movl    reg, (%edx)     ; \
 306         NON_LAZY_STUB(var)
 307
 308 #define EXTERN_TO_REG(var, reg)                         \
 309         call    1f                                      ; \
 310 1:                                                      ; \
 311         popl    %edx                                    ; \
 312         movl    L ## var ##$non_lazy_ptr-1b(%edx),reg   ; \
 313         NON_LAZY_STUB(var)
 314
 315
 316 #else
 317 #define BRANCH_EXTERN(func)     jmp     func
 318 #define PUSH_EXTERN(var)        pushl   var
 319 #define CALL_EXTERN(func)       call    func
 320 #define CALL_EXTERN_AGAIN(func) call    func
 321 #define REG_TO_EXTERN(reg, var) movl    reg, var
 322 #define EXTERN_TO_REG(var, reg) movl    $ ## var, reg
 323 #endif
 324
 325 #endif  /* __ASSEMBLER__ */
 326
 327 #endif  /* _ARCH_I386_ASM_HELP_H_ */