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-rw-r--r--sysdeps/posix/sprofil.c357
1 files changed, 357 insertions, 0 deletions
diff --git a/sysdeps/posix/sprofil.c b/sysdeps/posix/sprofil.c
new file mode 100644
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+++ b/sysdeps/posix/sprofil.c
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+/* Copyright (C) 2001 Free Software Foundation, Inc.
+   Contributed by David Mosberger-Tang <davidm@hpl.hp.com>.
+
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <assert.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <sys/time.h>
+#include <sys/profil.h>
+
+#ifndef SIGPROF
+# include <sysdeps/generic/sprofil.c>
+#else
+
+#include <libc-internal.h>
+
+struct region
+  {
+    size_t offset;
+    size_t nsamples;
+    unsigned int scale;
+    union
+      {
+	void *vp;
+	unsigned short *us;
+	unsigned int *ui;
+      }
+    sample;
+    size_t start;
+    size_t end;
+  };
+
+struct prof_info
+  {
+    unsigned int num_regions;
+    struct region *region;
+    struct region *last, *overflow;
+    struct itimerval saved_timer;
+    struct sigaction saved_action;
+  };
+
+static unsigned int overflow_counter;
+
+static struct region default_overflow_region =
+  {
+    offset:	0,
+    nsamples:	1,
+    scale:	2,
+    sample:	{ &overflow_counter },
+    start:	0,
+    end:	~(size_t) 0
+  };
+
+static struct prof_info prof_info;
+
+static inline unsigned long int
+pc_to_index (size_t pc, size_t offset, unsigned int scale, int prof_uint)
+{
+  size_t i = (pc - offset) / (prof_uint ? sizeof (int) : sizeof (short));
+
+  if (sizeof (unsigned long long int) > sizeof (size_t))
+    return (unsigned long long int) i * scale / 65536;
+  else
+    return i / 65536 * scale + i % 65536 * scale / 65536;
+}
+
+static inline size_t
+index_to_pc (unsigned long int n, size_t offset, unsigned int scale,
+	     int prof_uint)
+{
+  size_t pc, bin_size = (prof_uint ? sizeof (int) : sizeof (short));
+
+  if (sizeof (unsigned long long int) > sizeof (size_t))
+    pc = offset + (unsigned long long int) n * bin_size * 65536ull / scale;
+  else
+    pc = (offset + n * bin_size / scale * 65536
+	  + n * bin_size % scale * 65536 / scale);
+
+  if (pc_to_index (pc, offset, scale, prof_uint) < n)
+    /* Adjust for rounding error.  */
+    ++pc;
+
+  assert (pc_to_index (pc - 1, offset, scale, prof_uint) < n
+	  && pc_to_index (pc, offset, scale, prof_uint) >= n);
+
+  return pc;
+}
+
+static inline void
+profil_count (void *pcp, int prof_uint)
+{
+  struct region *region, *r = prof_info.last;
+  size_t lo, hi, mid, pc = (unsigned long int) pcp;
+  unsigned long int i;
+
+  /* Fast path: pc is in same region as before.  */
+  if (pc >= r->start && pc < r->end)
+    region = r;
+  else
+    {
+      /* Slow path: do a binary search for the right region.  */
+      lo = 0; hi = prof_info.num_regions - 1;
+      while (lo <= hi)
+	{
+	  mid = (lo + hi) / 2;
+
+	  r = prof_info.region + mid;
+	  if (pc >= r->start && pc < r->end)
+	    {
+	      prof_info.last = r;
+	      region = r;
+	      break;
+	    }
+
+	  if (pc < r->start)
+	    hi = mid - 1;
+	  else
+	    lo = mid + 1;
+	}
+
+      /* No matching region: increment overflow count.  There is no point
+	 in updating the cache here, as it won't hit anyhow.  */
+      region = prof_info.overflow;
+    }
+
+  i = pc_to_index (pc, region->offset, region->scale, prof_uint);
+  if (i < r->nsamples)
+    {
+      if (prof_uint)
+	{
+	  if (r->sample.ui[i] < (unsigned int) ~0)
+	    ++r->sample.ui[i];
+	}
+      else
+	{
+	  if (r->sample.us[i] < (unsigned short) ~0)
+	    ++r->sample.us[i];
+	}
+    }
+  else
+    {
+      if (prof_uint)
+	++prof_info.overflow->sample.ui[0];
+      else
+	++prof_info.overflow->sample.us[0];
+    }
+}
+
+static inline void
+profil_count_ushort (void *pcp)
+{
+  profil_count (pcp, 0);
+}
+
+static inline void
+profil_count_uint (void *pcp)
+{
+  profil_count (pcp, 1);
+}
+
+/* Get the machine-dependent definition of `profil_counter', the signal
+   handler for SIGPROF.  It calls `profil_count' (above) with the PC of the
+   interrupted code.  */
+#define profil_counter		profil_counter_ushort
+#define profil_count(pc)	profil_count (pc, 0)
+#include "profil-counter.h"
+
+#undef profil_counter
+#undef profil_count
+
+#define profil_counter		profil_counter_uint
+#define profil_count(pc)	profil_count (pc, 1)
+#include "profil-counter.h"
+
+static int
+insert (int i, unsigned long int start, unsigned long int end, struct prof *p,
+	int prof_uint)
+{
+  struct region *r;
+  size_t to_copy;
+
+  if (start >= end)
+    return 0;		/* don't bother with empty regions */
+
+  if (prof_info.num_regions == 0)
+    r = malloc (sizeof (*r));
+  else
+    r = realloc (prof_info.region, (prof_info.num_regions + 1) * sizeof (*r));
+  if (r == NULL)
+    return -1;
+
+  to_copy = prof_info.num_regions - i;
+  if (to_copy > 0)
+    memmove (r + i + 1, r + i, to_copy * sizeof (*r));
+
+  r[i].offset = p->pr_off;
+  r[i].nsamples = p->pr_size / (prof_uint ? sizeof (int) : sizeof (short));
+  r[i].scale = p->pr_scale;
+  r[i].sample.vp = p->pr_base;
+  r[i].start = start;
+  r[i].end = end;
+
+  prof_info.region = r;
+  ++prof_info.num_regions;
+
+  if (p->pr_off == 0 && p->pr_scale == 2)
+    prof_info.overflow = r;
+
+  return 0;
+}
+
+/* Add a new profiling region.  If the new region overlaps with
+   existing ones, this may add multiple subregions so that the final
+   data structure is free of overlaps.  The absence of overlaps makes
+   it possible to use a binary search in profil_count().  Note that
+   this function depends on new regions being presented in DECREASING
+   ORDER of starting address.  */
+
+static int
+add_region (struct prof *p, int prof_uint)
+{
+  unsigned long int nsamples;
+  size_t start, end;
+  int i;
+
+  if (p->pr_scale < 2)
+    return 0;
+
+  nsamples = p->pr_size / (prof_uint ? sizeof (int) : sizeof (short));
+
+  start = p->pr_off;
+  end = index_to_pc (nsamples, p->pr_off, p->pr_scale, prof_uint);
+
+  /* Merge with existing regions.  */
+  for (i = 0; i < prof_info.num_regions; ++i)
+    {
+      if (start < prof_info.region[i].start)
+	{
+	  if (end < prof_info.region[i].start)
+	    break;
+	  else if (insert (i, start, prof_info.region[i].start, p, prof_uint)
+		   < 0)
+	    return -1;
+	}
+      start = prof_info.region[i].end;
+    }
+  return insert (i, start, end, p, prof_uint);
+}
+
+static int
+pcmp (const void *left, const void *right)
+{
+  struct prof *l = *(struct prof **) left;
+  struct prof *r = *(struct prof **) right;
+
+  if (l->pr_off < r->pr_off)
+    return 1;
+  else if (l->pr_off > r->pr_off)
+    return -1;
+  return 0;
+}
+
+int
+__sprofil (struct prof *profp, int profcnt, struct timeval *tvp,
+	   unsigned int flags)
+{
+  struct prof *p[profcnt];
+  struct itimerval timer;
+  struct sigaction act;
+  int i;
+
+  if (tvp != NULL)
+    {
+      /* Return profiling period.  */
+      unsigned long int t = 1000000 / __profile_frequency ();
+      tvp->tv_sec  = t / 1000000;
+      tvp->tv_usec = t % 1000000;
+    }
+
+  if (prof_info.num_regions > 0)
+    {
+      /* Disable profiling.  */
+      if (__setitimer (ITIMER_PROF, &prof_info.saved_timer, NULL) < 0)
+	return -1;
+
+      if (__sigaction (SIGPROF, &prof_info.saved_action, NULL) < 0)
+	return -1;
+
+      free (prof_info.region);
+      return 0;
+    }
+
+  prof_info.num_regions = 0;
+  prof_info.region = NULL;
+  prof_info.overflow = &default_overflow_region;
+
+  for (i = 0; i < profcnt; ++i)
+    p[i] = profp + i;
+
+  /* Sort in order of decreasing starting address: */
+  qsort (p, profcnt, sizeof (p[0]), pcmp);
+
+  /* Add regions in order of decreasing starting address: */
+  for (i = 0; i < profcnt; ++i)
+    if (add_region (p[i], (flags & PROF_UINT) != 0) < 0)
+      {
+	if (prof_info.region)
+	  free (prof_info.region);
+	prof_info.num_regions = 0;
+	prof_info.region = NULL;
+	return -1;
+      }
+
+  if (prof_info.num_regions == 0)
+    return 0;
+
+  prof_info.last = prof_info.region;
+
+  /* Install SIGPROF handler.  */
+  if (flags & PROF_UINT)
+    act.sa_handler = (sighandler_t) &profil_counter_uint;
+  else
+    act.sa_handler = (sighandler_t) &profil_counter_ushort;
+  act.sa_flags = SA_RESTART;
+  sigfillset (&act.sa_mask);
+  if (__sigaction (SIGPROF, &act, &prof_info.saved_action) < 0)
+    return -1;
+
+  /* Setup profiling timer.  */
+  timer.it_value.tv_sec  = 0;
+  timer.it_value.tv_usec = 1;
+  timer.it_interval = timer.it_value;
+  return __setitimer (ITIMER_PROF, &timer, &prof_info.saved_timer);
+}
+
+weak_alias (__sprofil, sprofil)
+
+#endif /* SIGPROF */