mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-23 13:30:06 +00:00
119 lines
4.4 KiB
C
119 lines
4.4 KiB
C
/* High precision, low overhead timing functions. Alpha version.
|
|
Copyright (C) 2001 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
Contributed by Richard Henderson <rth@redhat.com>, 2001.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, write to the Free
|
|
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
|
|
02111-1307 USA. */
|
|
|
|
#ifndef _HP_TIMING_H
|
|
#define _HP_TIMING_H 1
|
|
|
|
#include <string.h>
|
|
#include <sys/param.h>
|
|
#include <stdio-common/_itoa.h>
|
|
|
|
/* The macros defined here use the timestamp counter in IA-64. They
|
|
provide a very accurate way to measure the time with very little
|
|
overhead. The time values themself have no real meaning, only
|
|
differences are interesting.
|
|
|
|
The list of macros we need includes the following:
|
|
|
|
- HP_TIMING_AVAIL: test for availability.
|
|
|
|
- HP_TIMING_INLINE: this macro is non-zero if the functionality is not
|
|
implemented using function calls but instead uses some inlined code
|
|
which might simply consist of a few assembler instructions. We have to
|
|
know this since we might want to use the macros here in places where we
|
|
cannot make function calls.
|
|
|
|
- hp_timing_t: This is the type for variables used to store the time
|
|
values.
|
|
|
|
- HP_TIMING_ZERO: clear `hp_timing_t' object.
|
|
|
|
- HP_TIMING_NOW: place timestamp for current time in variable given as
|
|
parameter.
|
|
|
|
- HP_TIMING_DIFF_INIT: do whatever is necessary to be able to use the
|
|
HP_TIMING_DIFF macro.
|
|
|
|
- HP_TIMING_DIFF: compute difference between two times and store it
|
|
in a third. Source and destination might overlap.
|
|
|
|
- HP_TIMING_ACCUM: add time difference to another variable. This might
|
|
be a bit more complicated to implement for some platforms as the
|
|
operation should be thread-safe and 64bit arithmetic on 32bit platforms
|
|
is not.
|
|
|
|
- HP_TIMING_ACCUM_NT: this is the variant for situations where we know
|
|
there are no threads involved.
|
|
|
|
- HP_TIMING_PRINT: write decimal representation of the timing value into
|
|
the given string. This operation need not be inline even though
|
|
HP_TIMING_INLINE is specified.
|
|
*/
|
|
|
|
/* We always have the timestamp register, but it's got only a 4 second
|
|
range. Use it for ld.so profiling only. */
|
|
#define HP_TIMING_AVAIL (0)
|
|
#define HP_SMALL_TIMING_AVAIL (1)
|
|
|
|
/* We indeed have inlined functions. */
|
|
#define HP_TIMING_INLINE (1)
|
|
|
|
/* We use 32 bit values for the times. */
|
|
typedef unsigned int hp_timing_t;
|
|
|
|
/* Set timestamp value to zero. */
|
|
#define HP_TIMING_ZERO(VAR) (VAR) = (0)
|
|
|
|
/* The "rpcc" instruction returns a 32-bit counting half and a 32-bit
|
|
"virtual cycle counter displacement". Subtracting the two gives us
|
|
a virtual cycle count. */
|
|
#define HP_TIMING_NOW(VAR) \
|
|
do { \
|
|
unsigned long int x_; \
|
|
asm volatile ("rpcc %0" : "=r"(x_)); \
|
|
(VAR) = (int) (x_) - (int) (x_ >> 32); \
|
|
} while (0)
|
|
|
|
/* ??? Two rpcc instructions can be scheduled simultaneously. */
|
|
#define HP_TIMING_DIFF_INIT() do { } while (0)
|
|
|
|
/* It's simple arithmetic for us. */
|
|
#define HP_TIMING_DIFF(Diff, Start, End) (Diff) = ((End) - (Start))
|
|
|
|
/* ??? Don't bother, since we're only used for ld.so. */
|
|
#define HP_TIMING_ACCUM(Sum, Diff) not implemented
|
|
|
|
/* No threads, no extra work. */
|
|
#define HP_TIMING_ACCUM_NT(Sum, Diff) (Sum) += (Diff)
|
|
|
|
/* Print the time value. */
|
|
#define HP_TIMING_PRINT(Buf, Len, Val) \
|
|
do { \
|
|
char __buf[20]; \
|
|
char *__cp = _itoa_word (Val, __buf + sizeof (__buf), 10, 0); \
|
|
int __len = (Len); \
|
|
char *__dest = (Buf); \
|
|
while (__len-- > 0 && __cp < __buf + sizeof (__buf)) \
|
|
*__dest++ = *__cp++; \
|
|
memcpy (__dest, " clock cycles", MIN (__len, sizeof (" clock cycles"))); \
|
|
} while (0)
|
|
|
|
#endif /* hp-timing.h */
|