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 #ifdef  __ASSEMBLER__
  23
  24 /* Syntactic details of assembler.  */
  25
  26 #ifdef HAVE_ELF
  27
  28 #define ALIGNARG(log2) log2
  29 /* For ELF we need the `.type' directive to make shared libs work right.  */
  30 #define ASM_TYPE_DIRECTIVE(name,typearg) .type name,%##typearg;
  31 #define ASM_SIZE_DIRECTIVE(name) .size name,.-name
  32
  33 /* In ELF C symbols are asm symbols.  */
  34 #undef  NO_UNDERSCORES
  35 #define NO_UNDERSCORES
  36
  37 #define PLTJMP(_x)      _x##(PLT)
  38
  39 #else
  40
  41 #define ALIGNARG(log2) log2
  42 #define ASM_TYPE_DIRECTIVE(name,type)   /* Nothing is specified.  */
  43 #define ASM_SIZE_DIRECTIVE(name)        /* Nothing is specified.  */
  44
  45 #define PLTJMP(_x)      _x
  46
  47 #endif
  48
  49 /* APCS-32 doesn't preserve the condition codes across function call. */
  50 #ifdef __APCS_32__
  51 #define LOADREGS(cond, base, reglist...)\
  52         ldm##cond       base,reglist
  53 #define RETINSTR(instr, regs...)\
  54         instr   regs
  55 #ifdef __THUMB_INTERWORK__
  56 #define DO_RET(_reg)            \
  57         bx _reg
  58 #else
  59 #define DO_RET(_reg)            \
  60         mov pc, _reg
  61 #endif
  62 #else  /* APCS-26 */
  63 #define LOADREGS(cond, base, reglist...)\
  64         ldm##cond       base,reglist^
  65 #define RETINSTR(instr, regs...)\
  66         instr##s        regs
  67 #define DO_RET(_reg)            \
  68         movs pc, _reg
  69 #endif
  70
  71 /* Define an entry point visible from C.  */
  72 #define ENTRY(name)                                                           \
  73   ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(name);                                   \
  74   ASM_TYPE_DIRECTIVE (C_SYMBOL_NAME(name),function)                           \
  75   .align ALIGNARG(4);                                                         \
  76   C_LABEL(name)                                                               \
  77   CALL_MCOUNT
  78
  79 #undef  END
  80 #define END(name)                                                             \
  81   ASM_SIZE_DIRECTIVE(name)
  82
  83 /* If compiled for profiling, call `mcount' at the start of each function.  */
  84 #ifdef  PROF
  85 #define CALL_MCOUNT                     \
  86         str     lr,[sp, #-4]!   ;       \
  87         bl      PLTJMP(mcount)  ;       \
  88         ldr     lr, [sp], #4    ;
  89 #else
  90 #define CALL_MCOUNT             /* Do nothing.  */
  91 #endif
  92
  93 #ifdef  NO_UNDERSCORES
  94 /* Since C identifiers are not normally prefixed with an underscore
  95    on this system, the asm identifier `syscall_error' intrudes on the
  96    C name space.  Make sure we use an innocuous name.  */
  97 #define syscall_error   __syscall_error
  98 #define mcount          _mcount
  99 #endif
 100
 101 #endif  /* __ASSEMBLER__ */