sysdeps/arm/machine-gmon.h

   1 /* Machine-dependent definitions for profiling support.  ARM version.
   2    Copyright (C) 1996, 1997, 1998 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 /* GCC for the ARM cannot compile __builtin_return_address(N) for N != 0,
  21    so we must use an assembly stub.  */
  22
  23 #include <sysdep.h>
  24 #ifndef NO_UNDERSCORES
  25 /* The asm symbols for C functions are `_function'.
  26    The canonical name for the counter function is `mcount', no _.  */
  27 void _mcount (void) asm ("mcount");
  28 #else
  29 /* The canonical name for the function is `_mcount' in both C and asm,
  30    but some old asm code might assume it's `mcount'.  */
  31 void _mcount (void);
  32 weak_alias (_mcount, mcount)
  33 #endif
  34
  35 static void mcount_internal (u_long frompc, u_long selfpc) __attribute_used__;
  36
  37 #define _MCOUNT_DECL(frompc, selfpc) \
  38 static void mcount_internal (u_long frompc, u_long selfpc)
  39
  40 /* This macro/func MUST save r0, r1 because the compiler inserts
  41         blind calls to _mount(), ignoring the fact that _mcount may
  42         clobber registers; therefore, _mcount may NOT clobber registers */
  43 /* if (this_fp!=0) {
  44         r0 = this_fp
  45         r1 = this_lr
  46         r1 = [r1-4] which is caller's lr
  47         if (r1!=0)
  48                 r1 = caller's lr
  49         call mcount_internal(this_lr, caller's_lr)
  50    }
  51 */
  52
  53 #define MCOUNT                                                          \
  54 void _mcount (void)                                                     \
  55 {                                                                       \
  56   __asm__("stmdb        sp!, {r0, r1, r2, r3};"                         \
  57           "movs         fp, fp;"                                        \
  58           "moveq        r1, #0;"                                        \
  59           "ldrne        r1, [fp, $-4];"                                 \
  60           "ldrne        r0, [fp, $-12];"                                \
  61           "movnes       r0, r0;"                                        \
  62           "ldrne        r0, [r0, $-4];"                                 \
  63           "movs         r0, r0;"                                        \
  64           "blne         mcount_internal;"                               \
  65           "ldmia        sp!, {r0, r1, r2, r3}");                        \
  66 }
  67