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+/* 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 */