sysdeps/aarch64/sysdep.h

   1 /* Copyright (C) 1997-2016 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, #-80]!;                               \
  70         cfi_adjust_cfa_offset (80);                             \
  71         cfi_rel_offset (x30, 0);                                \
  72         stp     x0, x1, [sp, #16];                              \
  73         cfi_rel_offset (x0, 16);                                \
  74         cfi_rel_offset (x1, 24);                                \
  75         stp     x2, x3, [sp, #32];                              \
  76         cfi_rel_offset (x2, 32);                                \
  77         cfi_rel_offset (x3, 40);                                \
  78         stp     x4, x5, [sp, #48];                              \
  79         cfi_rel_offset (x4, 48);                                \
  80         cfi_rel_offset (x5, 56);                                \
  81         stp     x6, x7, [sp, #64];                              \
  82         cfi_rel_offset (x6, 64);                                \
  83         cfi_rel_offset (x7, 72);                                \
  84         mov     x0, x30;                                        \
  85         bl      mcount;                                         \
  86         ldp     x0, x1, [sp, #16];                              \
  87         cfi_restore (x0);                                       \
  88         cfi_restore (x1);                                       \
  89         ldp     x2, x3, [sp, #32];                              \
  90         cfi_restore (x2);                                       \
  91         cfi_restore (x3);                                       \
  92         ldp     x4, x5, [sp, #48];                              \
  93         cfi_restore (x4);                                       \
  94         cfi_restore (x5);                                       \
  95         ldp     x6, x7, [sp, #64];                              \
  96         cfi_restore (x6);                                       \
  97         cfi_restore (x7);                                       \
  98         ldr     x30, [sp], #80;                                 \
  99         cfi_adjust_cfa_offset (-80);                            \
 100         cfi_restore (x30);
 101 #else
 102 # define CALL_MCOUNT            /* Do nothing.  */
 103 #endif
 104
 105 /* Local label name for asm code.  */
 106 #ifndef L
 107 # define L(name)         .L##name
 108 #endif
 109
 110 /* Load or store to/from a pc-relative EXPR into/from R, using T.  */
 111 #define LDST_PCREL(OP, R, T, EXPR)  \
 112         adrp    T, EXPR;            \
 113         OP      R, [T, #:lo12:EXPR];\
 114
 115 /* Load or store to/from a got-relative EXPR into/from R, using T.  */
 116 #define LDST_GLOBAL(OP, R, T, EXPR)     \
 117         adrp    T, :got:EXPR;           \
 118         ldr     T, [T, #:got_lo12:EXPR];\
 119         OP      R, [T];
 120
 121 /* Since C identifiers are not normally prefixed with an underscore
 122    on this system, the asm identifier `syscall_error' intrudes on the
 123    C name space.  Make sure we use an innocuous name.  */
 124 #define syscall_error   __syscall_error
 125 #define mcount          _mcount
 126
 127 #endif  /* __ASSEMBLER__ */