sysdeps/alpha/hp-timing.h

   1 /* High precision, low overhead timing functions.  Alpha version.
   2    Copyright (C) 2001-2024 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, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _HP_TIMING_ALPHA_H
  20 #define _HP_TIMING_ALPHA_H      1
  21
  22 #if IS_IN(rtld)
  23 /* We always have the timestamp register, but it's got only a 4 second
  24    range.  Use it for ld.so profiling only.  */
  25 # define HP_TIMING_INLINE       (1)
  26
  27 /* We use 32 bit values for the times.  */
  28 typedef unsigned int hp_timing_t;
  29
  30 /* The "rpcc" instruction returns a 32-bit counting half and a 32-bit
  31    "virtual cycle counter displacement".  Subtracting the two gives us
  32    a virtual cycle count.  */
  33 # define HP_TIMING_NOW(VAR) \
  34   do {                                                                        \
  35     unsigned long int x_;                                                     \
  36     asm volatile ("rpcc %0" : "=r"(x_));                                      \
  37     (VAR) = (int) (x_) - (int) (x_ >> 32);                                    \
  38   } while (0)
  39 # include <hp-timing-common.h>
  40
  41 #else
  42 # include <sysdeps/generic/hp-timing.h>
  43 #endif /* IS_IN(rtld)  */
  44
  45 #endif  /* hp-timing.h */