sysdeps/arm/sysdep.h

   1 /* Assembler macros for ARM.
   2    Copyright (C) 1997, 1998, 2003 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <sysdeps/generic/sysdep.h>
  21
  22 #if (!defined (__ARM_ARCH_2__) && !defined (__ARM_ARCH_3__) \
  23      && !defined (__ARM_ARCH_3M__) && !defined (__ARM_ARCH_4__))
  24 # define __USE_BX__
  25 #endif
  26
  27 #ifdef  __ASSEMBLER__
  28
  29 /* Syntactic details of assembler.  */
  30
  31 #ifdef HAVE_ELF
  32
  33 #define ALIGNARG(log2) log2
  34 /* For ELF we need the `.type' directive to make shared libs work right.  */
  35 #define ASM_TYPE_DIRECTIVE(name,typearg) .type name,%##typearg;
  36 #define ASM_SIZE_DIRECTIVE(name) .size name,.-name
  37
  38 /* In ELF C symbols are asm symbols.  */
  39 #undef  NO_UNDERSCORES
  40 #define NO_UNDERSCORES
  41
  42 #define PLTJMP(_x)      _x##(PLT)
  43
  44 #else
  45
  46 #define ALIGNARG(log2) log2
  47 #define ASM_TYPE_DIRECTIVE(name,type)   /* Nothing is specified.  */
  48 #define ASM_SIZE_DIRECTIVE(name)        /* Nothing is specified.  */
  49
  50 #define PLTJMP(_x)      _x
  51
  52 #endif
  53
  54 /* APCS-32 doesn't preserve the condition codes across function call. */
  55 #ifdef __APCS_32__
  56 #define LOADREGS(cond, base, reglist...)\
  57         ldm##cond       base,reglist
  58 #ifdef __USE_BX__
  59 #define RETINSTR(cond, reg)     \
  60         bx##cond        reg
  61 #define DO_RET(_reg)            \
  62         bx _reg
  63 #else
  64 #define RETINSTR(cond, reg)     \
  65         mov##cond       pc, reg
  66 #define DO_RET(_reg)            \
  67         mov pc, _reg
  68 #endif
  69 #else  /* APCS-26 */
  70 #define LOADREGS(cond, base, reglist...)\
  71         ldm##cond       base,reglist^
  72 #define RETINSTR(cond, reg)     \
  73         mov##cond##s    pc, reg
  74 #define DO_RET(_reg)            \
  75         movs pc, _reg
  76 #endif
  77
  78 /* Define an entry point visible from C.  */
  79 #define ENTRY(name)                                                           \
  80   ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(name);                                   \
  81   ASM_TYPE_DIRECTIVE (C_SYMBOL_NAME(name),function)                           \
  82   .align ALIGNARG(4);                                                         \
  83   C_LABEL(name)                                                               \
  84   CALL_MCOUNT
  85
  86 #undef  END
  87 #define END(name)                                                             \
  88   ASM_SIZE_DIRECTIVE(name)
  89
  90 /* If compiled for profiling, call `mcount' at the start of each function.  */
  91 #ifdef  PROF
  92 #define CALL_MCOUNT                     \
  93         str     lr,[sp, #-4]!   ;       \
  94         bl      PLTJMP(mcount)  ;       \
  95         ldr     lr, [sp], #4    ;
  96 #else
  97 #define CALL_MCOUNT             /* Do nothing.  */
  98 #endif
  99
 100 #ifdef  NO_UNDERSCORES
 101 /* Since C identifiers are not normally prefixed with an underscore
 102    on this system, the asm identifier `syscall_error' intrudes on the
 103    C name space.  Make sure we use an innocuous name.  */
 104 #define syscall_error   __syscall_error
 105 #define mcount          _mcount
 106 #endif
 107
 108 #endif  /* __ASSEMBLER__ */