sys/arch/sh3/include/asm.h

   1 /*      $NetBSD: asm.h,v 1.25 2006/01/20 22:02:40 christos Exp $        */
   2
   3 /*-
   4  * Copyright (c) 1990 The Regents of the University of California.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to Berkeley by
   8  * William Jolitz.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  *      @(#)asm.h       5.5 (Berkeley) 5/7/91
  35  */
  36
  37 #ifndef _SH3_ASM_H_
  38 #define _SH3_ASM_H_
  39
  40 /*
  41  * The old NetBSD/sh3 ELF toolchain used underscores.  The new
  42  * NetBSD/sh3 ELF toolchain does not.  The C pre-processor
  43  * defines __NO_LEADING_UNDERSCORES__ for the new ELF toolchain.
  44  */
  45
  46 #if defined(__ELF__) && defined(__NO_LEADING_UNDERSCORES__)
  47 # define _C_LABEL(x)    x
  48 #else
  49 #ifdef __STDC__
  50 # define _C_LABEL(x)    _ ## x
  51 #else
  52 # define _C_LABEL(x)    _/**/x
  53 #endif
  54 #endif
  55 #define _ASM_LABEL(x)   x
  56
  57 /* let kernels and others override entrypoint alignment */
  58 #ifndef _ALIGN_TEXT
  59 # define _ALIGN_TEXT .align 2
  60 #endif
  61
  62 #ifdef __ELF__
  63 #define _ENTRY(x)                                                       \
  64         .text                                                           ;\
  65         _ALIGN_TEXT                                                     ;\
  66         .globl x                                                        ;\
  67         .type x,@function                                               ;\
  68         x:
  69 #else /* !__ELF__ */
  70 #define _ENTRY(x)                                                       \
  71         .text                                                           ;\
  72         _ALIGN_TEXT                                                     ;\
  73         .globl x                                                        ;\
  74         x:
  75 #endif /* !__ELF__ */
  76
  77 #ifdef GPROF
  78 #define _PROF_PROLOGUE                            \
  79         mov.l   1f,r1                           ; \
  80         mova    2f,r0                           ; \
  81         jmp     @r1                             ; \
  82          nop                                    ; \
  83         .align  2                               ; \
  84 1:      .long   __mcount                        ; \
  85 2:
  86 #else  /* !GPROF */
  87 #define _PROF_PROLOGUE
  88 #endif /* !GPROF */
  89
  90 #define ENTRY(y)        _ENTRY(_C_LABEL(y)) _PROF_PROLOGUE
  91 #define NENTRY(y)       _ENTRY(_C_LABEL(y))
  92 #define ASENTRY(y)      _ENTRY(_ASM_LABEL(y)) _PROF_PROLOGUE
  93
  94 #define SET_ENTRY_SIZE(y) \
  95         .size   _C_LABEL(y), . - _C_LABEL(y)
  96
  97 #define SET_ASENTRY_SIZE(y) \
  98         .size   _ASM_LABEL(y), . - _ASM_LABEL(y)
  99
 100 #ifdef __ELF__
 101 #define ALTENTRY(name)                           \
 102         .globl _C_LABEL(name)                   ;\
 103         .type _C_LABEL(name),@function          ;\
 104         _C_LABEL(name):
 105 #else
 106 #define ALTENTRY(name)                           \
 107         .globl _C_LABEL(name)                   ;\
 108         _C_LABEL(name):
 109 #endif
 110
 111
 112 /*
 113  * Hide the gory details of PIC calls vs. normal calls.  Use as in the
 114  * following example:
 115  *
 116  *      sts.l   pr, @-sp
 117  *      PIC_PROLOGUE(.L_got, r0)        ! saves old r12 on stack
 118  *      ...
 119  *      mov.l   .L_function_1, r0
 120  * 1:   CALL    r0                      ! each call site needs a label
 121  *       nop
 122  *      ...
 123  *      mov.l   .L_function_2, r0
 124  * 2:   CALL    r0
 125  *       nop
 126  *      ...
 127  *      PIC_EPILOGUE                    ! restores r12 from stack
 128  *      lds.l   @sp+, pr                !  so call in right order
 129  *      rts
 130  *       nop
 131  *
 132  *      .align 2
 133  * .L_got:
 134  *      PIC_GOT_DATUM
 135  * .L_function_1:                       ! if you call the same function twice
 136  *      CALL_DATUM(function, 1b)        !  provide call datum for each call
 137  * .L_function_2:
 138  *      CALL_DATUM(function, 2b)
 139  */
 140
 141 #ifdef PIC
 142
 143 #define PIC_PLT(x)      x@PLT
 144 #define PIC_GOT(x)      x@GOT
 145 #define PIC_GOTOFF(x)   x@GOTOFF
 146
 147 #define PIC_PROLOGUE(got)                       \
 148                 mov.l   r12, @-sp;              \
 149                 PIC_PROLOGUE_NOSAVE(got)
 150
 151 /*
 152  * Functions that do non local jumps don't need to preserve r12,
 153  * so we can shave off two instructions to save/restore it.
 154  */
 155 #define PIC_PROLOGUE_NOSAVE(got)                \
 156                 mov.l   got, r12;               \
 157                 mova    got, r0;                \
 158                 add     r0, r12
 159
 160 #define PIC_EPILOGUE                            \
 161                 mov.l   @sp+, r12
 162
 163 #define PIC_EPILOGUE_SLOT                       \
 164                 PIC_EPILOGUE
 165
 166 #define PIC_GOT_DATUM \
 167                 .long   _GLOBAL_OFFSET_TABLE_
 168
 169 #define CALL    bsrf
 170 #define JUMP    braf
 171
 172 #define CALL_DATUM(function, lpcs) \
 173                 .long   PIC_PLT(function) - ((lpcs) + 4 - (.))
 174
 175 /*
 176  * This will result in text relocations in the shared library,
 177  * unless the function is local or has hidden or protected visibility.
 178  * Does not require PIC prologue.
 179  */
 180 #define CALL_DATUM_LOCAL(function, lpcs) \
 181                 .long   function - ((lpcs) + 4)
 182
 183 #else  /* !PIC */
 184
 185 #define PIC_PROLOGUE(label)
 186 #define PIC_PROLOGUE_NOSAVE(label)
 187 #define PIC_EPILOGUE
 188 #define PIC_EPILOGUE_SLOT       nop
 189 #define PIC_GOT_DATUM
 190
 191 #define CALL    jsr @
 192 #define JUMP    jmp @
 193
 194 #define CALL_DATUM(function, lpcs) \
 195                 .long   function
 196
 197 #define CALL_DATUM_LOCAL(function, lpcs) \
 198                 .long   function
 199
 200 #endif /* !PIC */
 201
 202
 203 #define ASMSTR          .asciz
 204
 205 #ifdef __ELF__
 206 #define RCSID(x)        .pushsection ".ident"; .asciz x; .popsection
 207 #else
 208 #define RCSID(x)        .text; .asciz x
 209 #endif
 210
 211 #ifdef NO_KERNEL_RCSIDS
 212 #define __KERNEL_RCSID(_n, _s)  /* nothing */
 213 #else
 214 #define __KERNEL_RCSID(_n, _s)  RCSID(_s)
 215 #endif
 216
 217 #ifdef __ELF__
 218 #define WEAK_ALIAS(alias,sym)                                           \
 219         .weak _C_LABEL(alias);                                          \
 220         _C_LABEL(alias) = _C_LABEL(sym)
 221 #endif
 222
 223 /*
 224  * STRONG_ALIAS: create a strong alias.
 225  */
 226 #define STRONG_ALIAS(alias,sym)                                         \
 227         .globl _C_LABEL(alias);                                         \
 228         _C_LABEL(alias) = _C_LABEL(sym)
 229
 230 #define WARN_REFERENCES(_sym,_msg)                              \
 231         .section .gnu.warning._sym; .ascii _msg; .previous
 232
 233 #endif /* !_SH3_ASM_H_ */