* sysdeps/powerpc/powerpc32/power4/hp-timing.c: New file.

* sysdeps/powerpc/powerpc32/power4/hp-timing.h: New file. * sysdeps/powerpc/powerpc64/hp-timing.h [_ARCH_PWR4] (HP_TIMING_NOW): For ISA 2.01 and later replace mftb with mfspr 268. * sysdeps/i386/i686/memcpy.S: Optimize copying of equally aligned buffers.
git-mirror · Apr 10, 2008 · 13d8332 · 13d8332
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diff --git a/ChangeLog b/ChangeLog
@@ -1,3 +1,10 @@
+2008-04-03  Steven Munroe  <sjmunroe@us.ibm.com>
+
+	* sysdeps/powerpc/powerpc32/power4/hp-timing.c: New file.
+	* sysdeps/powerpc/powerpc32/power4/hp-timing.h: New file.
+	* sysdeps/powerpc/powerpc64/hp-timing.h [_ARCH_PWR4] (HP_TIMING_NOW):
+	For ISA 2.01 and later replace mftb with mfspr 268.
+
 2008-02-19  Steven Munroe  <sjmunroe@us.ibm.com>
 
 	[BZ #5768]
@@ -51,7 +58,8 @@
 2008-04-09  Ulrich Drepper  <drepper@redhat.com>
 
 	[BZ #4314]
-	* sysdeps/i386/i686/memcpy.S: Optimize copying of aligned buffers.
+	* sysdeps/i386/i686/memcpy.S: Optimize copying of equally aligned
+	buffers.
 
 	[BZ #5209]
 	* sysdeps/unix/sysv/syscalls.list: The times syscall doesn't return

diff --git a/sysdeps/powerpc/powerpc32/power4/hp-timing.c b/sysdeps/powerpc/powerpc32/power4/hp-timing.c
@@ -0,0 +1,25 @@
+/* Support for high precision, low overhead timing functions. 
+   powerpc64 version.
+   Copyright (C) 2005, 2008 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.  */
+
+#include <hp-timing.h>
+
+/* We have to define the variable for the overhead.  */
+hp_timing_t _dl_hp_timing_overhead;
diff --git a/sysdeps/powerpc/powerpc32/power4/hp-timing.h b/sysdeps/powerpc/powerpc32/power4/hp-timing.h
@@ -0,0 +1,152 @@
+/* High precision, low overhead timing functions.  powerpc64 version.
+   Copyright (C) 2005, 2008 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.  */
+
+#ifndef _HP_TIMING_H
+#define _HP_TIMING_H	1
+
+#include <string.h>
+#include <sys/param.h>
+#include <stdio-common/_itoa.h>
+#include <atomic.h>
+
+/* The macros defined here use the powerpc 64-bit time base register.
+   The time base is nominally clocked at 1/8th the CPU clock, but this
+   can vary.
+
+   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;
+
+/* Set timestamp value to zero.  */
+#define HP_TIMING_ZERO(Var)	(Var) = (0)
+
+/* That's quite simple.  Use the `mftb' 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
+   'lwsync' right before the `mftb' instruciton.  But we are not interested
+   in accurate clock cycles here so we don't do this.  */
+
+#define HP_TIMING_NOW(Var)						\
+  do {									\
+        union { long long ll; long ii[2]; } _var;			\
+	long tmp;							\
+        __asm__ __volatile__ (						\
+		"1:	mfspr	%0,269;"				\
+		"	mfspr	%1,268;"				\
+		"	mfspr	%2,269;"				\
+		"	cmpw	%0,%2;"					\
+		"	bne	1b;"					\
+		: "=r" (_var.ii[0]), "=r" (_var.ii[1]) , "=r" (tmp)	\
+		: : "cr0"						\
+		);							\
+	Var = _var.ll;							\
+  } while (0)
+
+
+/* Use two 'mftb' instructions in a row to find out how long it takes.
+   On current POWER4, POWER5, and 970 processors mftb take ~10 cycles.  */
+#define HP_TIMING_DIFF_INIT() \
+  do {									      \
+    if (GLRO(dl_hp_timing_overhead) == 0)				      \
+      {									      \
+	int __cnt = 5;							      \
+	GLRO(dl_hp_timing_overhead) = ~0ull;				      \
+	do								      \
+	  {								      \
+	    hp_timing_t __t1, __t2;					      \
+	    HP_TIMING_NOW (__t1);					      \
+	    HP_TIMING_NOW (__t2);					      \
+	    if (__t2 - __t1 < GLRO(dl_hp_timing_overhead))		      \
+	      GLRO(dl_hp_timing_overhead) = __t2 - __t1;		      \
+	  }								      \
+	while (--__cnt > 0);						      \
+      }									      \
+  } while (0)
+
+/* It's simple arithmetic in 64-bit.  */
+#define HP_TIMING_DIFF(Diff, Start, End)	(Diff) = ((End) - (Start))
+
+/* We need to insure that this add is atomic in threaded environments.  We use
+   __arch_atomic_exchange_and_add_64 from atomic.h to get thread safety.  */
+#define HP_TIMING_ACCUM(Sum, Diff) \
+  do {									      \
+    hp_timing_t __diff = (Diff) - GLRO(dl_hp_timing_overhead);		      \
+    __arch_atomic_exchange_and_add_64 (&(Sum), __diff);	                      \
+  } 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 = _itoa (Val, __buf + sizeof (__buf), 10, 0);		      \
+    size_t __len = (Len);						      \
+    char *__dest = (Buf);						      \
+    while (__len-- > 0 && __cp < __buf + sizeof (__buf))		      \
+      *__dest++ = *__cp++;						      \
+    memcpy (__dest, " ticks", MIN (__len, sizeof (" ticks")));  \
+  } while (0)
+
+#endif	/* hp-timing.h */
diff --git a/sysdeps/powerpc/powerpc64/hp-timing.h b/sysdeps/powerpc/powerpc64/hp-timing.h
@@ -1,5 +1,5 @@
 /* High precision, low overhead timing functions.  powerpc64 version.
-   Copyright (C) 2005 Free Software Foundation, Inc.
+   Copyright (C) 2005, 2008 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
 
@@ -85,7 +85,11 @@ typedef unsigned long long int hp_timing_t;
    running in this moment.  This could be changed by using a barrier like
    'lwsync' right before the `mftb' instruciton.  But we are not interested
    in accurate clock cycles here so we don't do this.  */
+#ifdef _ARCH_PWR4
+#define HP_TIMING_NOW(Var)	__asm__ __volatile__ ("mfspr %0,268" : "=r" (Var))
+#else
 #define HP_TIMING_NOW(Var)	__asm__ __volatile__ ("mftb %0" : "=r" (Var))
+#endif
 
 /* Use two 'mftb' instructions in a row to find out how long it takes.
    On current POWER4, POWER5, and 970 processors mftb take ~10 cycles.  */