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Diffstat (limited to 'newlib/libc/sys/linux/machine/i386/hp-timing.h')
| -rw-r--r-- | newlib/libc/sys/linux/machine/i386/hp-timing.h | 187 |
1 files changed, 0 insertions, 187 deletions
diff --git a/newlib/libc/sys/linux/machine/i386/hp-timing.h b/newlib/libc/sys/linux/machine/i386/hp-timing.h deleted file mode 100644 index a34965ec8..000000000 --- a/newlib/libc/sys/linux/machine/i386/hp-timing.h +++ /dev/null @@ -1,187 +0,0 @@ -/* High precision, low overhead timing functions. i686 version. - Copyright (C) 1998 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998. - - 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. */ - -/* Modified for newlib by Jeff Johnston - June 27, 2002 */ - -#ifndef _HP_TIMING_H -#define _HP_TIMING_H 1 - -#include <string.h> -#include <stdio.h> -#include <sys/param.h> - -#ifdef __i686__ - -/* The macros defined here use the timestamp counter in i586 and up versions - of the x86 processors. 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. - - This version is for the i686 processors. The difference to the i586 - version is that the timerstamp register is unconditionally used. This is - not the case for the i586 version where we have to perform runtime test - whether the processor really has this capability. We have to make this - distinction since the sysdeps/i386/i586 code is supposed to work on all - platforms while the i686 already contains i686-specific code. - - 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 assume having the timestamp register. */ -#define HP_TIMING_AVAIL (1) - -/* We indeed have inlined functions. */ -#define HP_TIMING_INLINE (1) - -/* We use 64bit values for the times. */ -typedef unsigned long long int hp_timing_t; - -/* Internal variable used to store the overhead of the measurement - opcodes. */ -extern hp_timing_t __libc_hp_timing_overhead; - -/* Set timestamp value to zero. */ -#define HP_TIMING_ZERO(Var) (Var) = (0) - -/* That's quite simple. Use the `rdtsc' instruction. Note that the value - might not be 100% accurate since there might be some more instructions - running in this moment. This could be changed by using a barrier like - 'cpuid' right before the `rdtsc' instruciton. But we are not interested - in accurate clock cycles here so we don't do this. */ -#define HP_TIMING_NOW(Var) __asm__ __volatile__ ("rdtsc" : "=A" (Var)) - -/* Use two 'rdtsc' instructions in a row to find out how long it takes. */ -#define HP_TIMING_DIFF_INIT() \ - do { \ - int __cnt = 5; \ - __libc_hp_timing_overhead = ~0ull; \ - do \ - { \ - hp_timing_t __t1, __t2; \ - HP_TIMING_NOW (__t1); \ - HP_TIMING_NOW (__t2); \ - if (__t2 - __t1 < __libc_hp_timing_overhead) \ - __libc_hp_timing_overhead = __t2 - __t1; \ - } \ - while (--__cnt > 0); \ - } while (0) - -/* It's simple arithmetic for us. */ -#define HP_TIMING_DIFF(Diff, Start, End) (Diff) = ((End) - (Start)) - -/* We have to jump through hoops to get this correctly implemented. */ -#define HP_TIMING_ACCUM(Sum, Diff) \ - do { \ - char __not_done; \ - hp_timing_t __oldval = (Sum); \ - hp_timing_t __diff = (Diff) - __libc_hp_timing_overhead; \ - do \ - { \ - hp_timing_t __newval = __oldval + __diff; \ - int __temp0, __temp1; \ - __asm__ __volatile__ ("xchgl %4, %%ebx\n\t" \ - "lock; cmpxchg8b %1\n\t" \ - "sete %0\n\t" \ - "movl %4, %%ebx" \ - : "=q" (__not_done), "=m" (Sum), \ - "=A" (__oldval), "=c" (__temp0), \ - "=SD" (__temp1) \ - : "1" (Sum), "2" (__oldval), \ - "3" (__newval >> 32), \ - "4" (__newval & 0xffffffff) \ - : "memory"); \ - } \ - while (__not_done); \ - } while (0) - -/* 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 = __buf + sizeof (__buf); \ - int __len = (Len); \ - char *__dest = (Buf); \ - do { \ - *--__cp = Val % 10; \ - Val /= 10; \ - } while (Val > 0); \ - while (__len-- > 0 && __cp < __buf + sizeof (__buf)) \ - *__dest++ = *__cp++; \ - memcpy (__dest, " clock cycles", MIN (__len, sizeof (" clock cycles"))); \ - } while (0) - -#else /* !__i686__ */ - -/* Provide dummy definitions. */ -#define HP_TIMING_AVAIL (0) -#define HP_TIMING_INLINE (0) -typedef int hp_timing_t; -#define HP_TIMING_ZERO(Var) -#define HP_TIMING_NOW(var) -#define HP_TIMING_DIFF_INIT() -#define HP_TIMING_DIFF(Diff, Start, End) -#define HP_TIMING_ACCUM(Sum, Diff) -#define HP_TIMING_ACCUM_NT(Sum, Diff) -#define HP_TIMING_PRINT(Buf, Len, Val) - -/* Since this implementation is not available we tell the user about it. */ -#define HP_TIMING_NONAVAIL 1 - -#endif - -#endif /* hp-timing.h */ |