sysdeps/aarch64/sysdep.h

   1 /* Copyright (C) 1997-2015 Free Software Foundation, Inc.
   2
   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 License as
   7    published by the Free Software Foundation; either version 2.1 of the
   8    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, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <sysdeps/generic/sysdep.h>
  20
  21 #ifdef  __ASSEMBLER__
  22
  23 /* Syntactic details of assembler.  */
  24
  25 #define ASM_SIZE_DIRECTIVE(name) .size name,.-name
  26
  27 /* Define an entry point visible from C.  */
  28 #define ENTRY(name)                                             \
  29   .globl C_SYMBOL_NAME(name);                                   \
  30   .type C_SYMBOL_NAME(name),%function;                          \
  31   .align 4;                                                     \
  32   C_LABEL(name)                                                 \
  33   cfi_startproc;                                                \
  34   CALL_MCOUNT
  35
  36 /* Define an entry point visible from C.  */
  37 #define ENTRY_ALIGN(name, align)                                \
  38   .globl C_SYMBOL_NAME(name);                                   \
  39   .type C_SYMBOL_NAME(name),%function;                          \
  40   .p2align align;                                               \
  41   C_LABEL(name)                                                 \
  42   cfi_startproc;                                                \
  43   CALL_MCOUNT
  44
  45 /* Define an entry point visible from C with a specified alignment and
  46    pre-padding with NOPs.  This can be used to ensure that a critical
  47    loop within a function is cache line aligned.  Note this version
  48    does not adjust the padding if CALL_MCOUNT is defined. */
  49
  50 #define ENTRY_ALIGN_AND_PAD(name, align, padding)               \
  51   .globl C_SYMBOL_NAME(name);                                   \
  52   .type C_SYMBOL_NAME(name),%function;                          \
  53   .p2align align;                                               \
  54   .rep padding;                                                 \
  55   nop;                                                          \
  56   .endr;                                                        \
  57   C_LABEL(name)                                                 \
  58   cfi_startproc;                                                \
  59   CALL_MCOUNT
  60
  61 #undef  END
  62 #define END(name)                                               \
  63   cfi_endproc;                                                  \
  64   ASM_SIZE_DIRECTIVE(name)
  65
  66 /* If compiled for profiling, call `mcount' at the start of each function.  */
  67 #ifdef  PROF
  68 # define CALL_MCOUNT                                            \
  69         str     x30, [sp, #-16]!;                               \
  70         bl      mcount;                                         \
  71         ldr     x30, [sp], #16  ;
  72 #else
  73 # define CALL_MCOUNT            /* Do nothing.  */
  74 #endif
  75
  76 /* Local label name for asm code.  */
  77 #ifndef L
  78 # define L(name)         .L##name
  79 #endif
  80
  81 /* Load or store to/from a pc-relative EXPR into/from R, using T.  */
  82 #define LDST_PCREL(OP, R, T, EXPR)  \
  83         adrp    T, EXPR;            \
  84         OP      R, [T, #:lo12:EXPR];\
  85
  86 /* Load or store to/from a got-relative EXPR into/from R, using T.  */
  87 #define LDST_GLOBAL(OP, R, T, EXPR)     \
  88         adrp    T, :got:EXPR;           \
  89         ldr     T, [T, #:got_lo12:EXPR];\
  90         OP      R, [T];
  91
  92 /* Since C identifiers are not normally prefixed with an underscore
  93    on this system, the asm identifier `syscall_error' intrudes on the
  94    C name space.  Make sure we use an innocuous name.  */
  95 #define syscall_error   __syscall_error
  96 #define mcount          _mcount
  97
  98 #endif  /* __ASSEMBLER__ */