| /* High precision, low overhead timing functions. Alpha version. |
| Copyright (C) 2001-2014 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, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #ifndef _HP_TIMING_H |
| #define _HP_TIMING_H 1 |
| |
| #include <string.h> |
| #include <sys/param.h> |
| #include <_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 */ |