binutils-gdb/gprof/hist.c

594 lines
15 KiB
C

/*
* Histogram related operations.
*/
#include <stdio.h>
#include "libiberty.h"
#include "gprof.h"
#include "core.h"
#include "gmon_io.h"
#include "gmon_out.h"
#include "hist.h"
#include "symtab.h"
#include "sym_ids.h"
#include "utils.h"
static void scale_and_align_entries PARAMS ((void));
/* declarations of automatically generated functions to output blurbs: */
extern void flat_blurb PARAMS ((FILE * fp));
bfd_vma s_lowpc; /* lowest address in .text */
bfd_vma s_highpc = 0; /* highest address in .text */
bfd_vma lowpc, highpc; /* same, but expressed in UNITs */
int hist_num_bins = 0; /* number of histogram samples */
int *hist_sample = 0; /* histogram samples (shorts in the file!) */
double hist_scale;
char hist_dimension[sizeof (((struct gmon_hist_hdr *) 0)->dimen) + 1] =
"seconds";
char hist_dimension_abbrev = 's';
static double accum_time; /* accumulated time so far for print_line() */
static double total_time; /* total time for all routines */
/*
* Table of SI prefixes for powers of 10 (used to automatically
* scale some of the values in the flat profile).
*/
const struct
{
char prefix;
double scale;
}
SItab[] =
{
{
'T', 1e-12
}
, /* tera */
{
'G', 1e-09
}
, /* giga */
{
'M', 1e-06
}
, /* mega */
{
'K', 1e-03
}
, /* kilo */
{
' ', 1e-00
}
,
{
'm', 1e+03
}
, /* milli */
{
'u', 1e+06
}
, /* micro */
{
'n', 1e+09
}
, /* nano */
{
'p', 1e+12
}
, /* pico */
{
'f', 1e+15
}
, /* femto */
{
'a', 1e+18
}
, /* ato */
};
/*
* Read the histogram from file IFP. FILENAME is the name of IFP and
* is provided for formatting error messages only.
*/
void
DEFUN (hist_read_rec, (ifp, filename), FILE * ifp AND const char *filename)
{
struct gmon_hist_hdr hdr;
bfd_vma n_lowpc, n_highpc;
int i, ncnt, profrate;
UNIT count;
if (fread (&hdr, sizeof (hdr), 1, ifp) != 1)
{
fprintf (stderr, "%s: %s: unexpected end of file\n",
whoami, filename);
done (1);
}
n_lowpc = (bfd_vma) get_vma (core_bfd, (bfd_byte *) hdr.low_pc);
n_highpc = (bfd_vma) get_vma (core_bfd, (bfd_byte *) hdr.high_pc);
ncnt = bfd_get_32 (core_bfd, (bfd_byte *) hdr.hist_size);
profrate = bfd_get_32 (core_bfd, (bfd_byte *) hdr.prof_rate);
strncpy (hist_dimension, hdr.dimen, sizeof (hdr.dimen));
hist_dimension[sizeof (hdr.dimen)] = '\0';
hist_dimension_abbrev = hdr.dimen_abbrev;
if (!s_highpc)
{
/* this is the first histogram record: */
s_lowpc = n_lowpc;
s_highpc = n_highpc;
lowpc = (bfd_vma) n_lowpc / sizeof (UNIT);
highpc = (bfd_vma) n_highpc / sizeof (UNIT);
hist_num_bins = ncnt;
hz = profrate;
}
DBG (SAMPLEDEBUG,
printf ("[hist_read_rec] n_lowpc 0x%lx n_highpc 0x%lx ncnt %d\n",
n_lowpc, n_highpc, ncnt);
printf ("[hist_read_rec] s_lowpc 0x%lx s_highpc 0x%lx nsamples %d\n",
s_lowpc, s_highpc, hist_num_bins);
printf ("[hist_read_rec] lowpc 0x%lx highpc 0x%lx\n",
lowpc, highpc));
if (n_lowpc != s_lowpc || n_highpc != s_highpc
|| ncnt != hist_num_bins || hz != profrate)
{
fprintf (stderr, "%s: `%s' is incompatible with first gmon file\n",
whoami, filename);
done (1);
}
if (!hist_sample)
{
hist_sample = (int *) xmalloc (hist_num_bins * sizeof (hist_sample[0]));
memset (hist_sample, 0, hist_num_bins * sizeof (hist_sample[0]));
}
for (i = 0; i < hist_num_bins; ++i)
{
if (fread (&count[0], sizeof (count), 1, ifp) != 1)
{
fprintf (stderr,
"%s: %s: unexpected EOF after reading %d of %d samples\n",
whoami, filename, i, hist_num_bins);
done (1);
}
hist_sample[i] += bfd_get_16 (core_bfd, (bfd_byte *) & count[0]);
}
}
/*
* Write execution histogram to file OFP. FILENAME is the name
* of OFP and is provided for formatting error-messages only.
*/
void
DEFUN (hist_write_hist, (ofp, filename), FILE * ofp AND const char *filename)
{
struct gmon_hist_hdr hdr;
unsigned char tag;
UNIT count;
int i;
/* write header: */
tag = GMON_TAG_TIME_HIST;
put_vma (core_bfd, s_lowpc, (bfd_byte *) hdr.low_pc);
put_vma (core_bfd, s_highpc, (bfd_byte *) hdr.high_pc);
bfd_put_32 (core_bfd, hist_num_bins, (bfd_byte *) hdr.hist_size);
bfd_put_32 (core_bfd, hz, (bfd_byte *) hdr.prof_rate);
strncpy (hdr.dimen, hist_dimension, sizeof (hdr.dimen));
hdr.dimen_abbrev = hist_dimension_abbrev;
if (fwrite (&tag, sizeof (tag), 1, ofp) != 1
|| fwrite (&hdr, sizeof (hdr), 1, ofp) != 1)
{
perror (filename);
done (1);
}
for (i = 0; i < hist_num_bins; ++i)
{
bfd_put_16 (core_bfd, hist_sample[i], (bfd_byte *) & count[0]);
if (fwrite (&count[0], sizeof (count), 1, ofp) != 1)
{
perror (filename);
done (1);
}
}
}
/*
* Calculate scaled entry point addresses (to save time in
* hist_assign_samples), and, on architectures that have procedure
* entry masks at the start of a function, possibly push the scaled
* entry points over the procedure entry mask, if it turns out that
* the entry point is in one bin and the code for a routine is in the
* next bin.
*/
static void
scale_and_align_entries ()
{
Sym *sym;
bfd_vma bin_of_entry;
bfd_vma bin_of_code;
for (sym = symtab.base; sym < symtab.limit; sym++)
{
sym->hist.scaled_addr = sym->addr / sizeof (UNIT);
bin_of_entry = (sym->hist.scaled_addr - lowpc) / hist_scale;
bin_of_code = (sym->hist.scaled_addr + UNITS_TO_CODE - lowpc) / hist_scale;
if (bin_of_entry < bin_of_code)
{
DBG (SAMPLEDEBUG,
printf ("[scale_and_align_entries] pushing 0x%lx to 0x%lx\n",
sym->hist.scaled_addr,
sym->hist.scaled_addr + UNITS_TO_CODE));
sym->hist.scaled_addr += UNITS_TO_CODE;
}
}
}
/*
* Assign samples to the symbol to which they belong.
*
* Histogram bin I covers some address range [BIN_LOWPC,BIN_HIGH_PC)
* which may overlap one more symbol address ranges. If a symbol
* overlaps with the bin's address range by O percent, then O percent
* of the bin's count is credited to that symbol.
*
* There are three cases as to where BIN_LOW_PC and BIN_HIGH_PC can be
* with respect to the symbol's address range [SYM_LOW_PC,
* SYM_HIGH_PC) as shown in the following diagram. OVERLAP computes
* the distance (in UNITs) between the arrows, the fraction of the
* sample that is to be credited to the symbol which starts at
* SYM_LOW_PC.
*
* sym_low_pc sym_high_pc
* | |
* v v
*
* +-----------------------------------------------+
* | |
* | ->| |<- ->| |<- ->| |<- |
* | | | | | |
* +---------+ +---------+ +---------+
*
* ^ ^ ^ ^ ^ ^
* | | | | | |
* bin_low_pc bin_high_pc bin_low_pc bin_high_pc bin_low_pc bin_high_pc
*
* For the VAX we assert that samples will never fall in the first two
* bytes of any routine, since that is the entry mask, thus we call
* scale_and_align_entries() to adjust the entry points if the entry
* mask falls in one bin but the code for the routine doesn't start
* until the next bin. In conjunction with the alignment of routine
* addresses, this should allow us to have only one sample for every
* four bytes of text space and never have any overlap (the two end
* cases, above).
*/
void
DEFUN_VOID (hist_assign_samples)
{
bfd_vma bin_low_pc, bin_high_pc;
bfd_vma sym_low_pc, sym_high_pc;
bfd_vma overlap, addr;
int bin_count, i, j;
double time, credit;
/* read samples and assign to symbols: */
hist_scale = highpc - lowpc;
hist_scale /= hist_num_bins;
scale_and_align_entries ();
/* iterate over all sample bins: */
for (i = 0, j = 1; i < hist_num_bins; ++i)
{
bin_count = hist_sample[i];
if (!bin_count)
{
continue;
}
bin_low_pc = lowpc + (bfd_vma) (hist_scale * i);
bin_high_pc = lowpc + (bfd_vma) (hist_scale * (i + 1));
time = bin_count;
DBG (SAMPLEDEBUG,
printf (
"[assign_samples] bin_low_pc=0x%lx, bin_high_pc=0x%lx, bin_count=%d\n",
sizeof (UNIT) * bin_low_pc, sizeof (UNIT) * bin_high_pc,
bin_count));
total_time += time;
/* credit all symbols that are covered by bin I: */
for (j = j - 1; j < symtab.len; ++j)
{
sym_low_pc = symtab.base[j].hist.scaled_addr;
sym_high_pc = symtab.base[j + 1].hist.scaled_addr;
/*
* If high end of bin is below entry address, go for next
* bin:
*/
if (bin_high_pc < sym_low_pc)
{
break;
}
/*
* If low end of bin is above high end of symbol, go for
* next symbol.
*/
if (bin_low_pc >= sym_high_pc)
{
continue;
}
overlap =
MIN (bin_high_pc, sym_high_pc) - MAX (bin_low_pc, sym_low_pc);
if (overlap > 0)
{
DBG (SAMPLEDEBUG,
printf (
"[assign_samples] [0x%lx,0x%lx) %s gets %f ticks %ld overlap\n",
symtab.base[j].addr, sizeof (UNIT) * sym_high_pc,
symtab.base[j].name, overlap * time / hist_scale,
overlap));
addr = symtab.base[j].addr;
credit = overlap * time / hist_scale;
/*
* Credit symbol if it appears in INCL_FLAT or that
* table is empty and it does not appear it in
* EXCL_FLAT.
*/
if (sym_lookup (&syms[INCL_FLAT], addr)
|| (syms[INCL_FLAT].len == 0
&& !sym_lookup (&syms[EXCL_FLAT], addr)))
{
symtab.base[j].hist.time += credit;
}
else
{
total_time -= credit;
}
}
}
}
DBG (SAMPLEDEBUG, printf ("[assign_samples] total_time %f\n",
total_time));
}
/*
* Print header for flag histogram profile:
*/
static void
DEFUN (print_header, (prefix), const char prefix)
{
char unit[64];
sprintf (unit, "%c%c/call", prefix, hist_dimension_abbrev);
if (bsd_style_output)
{
printf ("\ngranularity: each sample hit covers %ld byte(s)",
(long) hist_scale * sizeof (UNIT));
if (total_time > 0.0)
{
printf (" for %.2f%% of %.2f %s\n\n",
100.0 / total_time, total_time / hz, hist_dimension);
}
}
else
{
printf ("\nEach sample counts as %g %s.\n", 1.0 / hz, hist_dimension);
}
if (total_time <= 0.0)
{
printf (" no time accumulated\n\n");
/* this doesn't hurt since all the numerators will be zero: */
total_time = 1.0;
}
printf ("%5.5s %10.10s %8.8s %8.8s %8.8s %8.8s %-8.8s\n",
"% ", "cumulative", "self ", "", "self ", "total ", "");
printf ("%5.5s %9.9s %8.8s %8.8s %8.8s %8.8s %-8.8s\n",
"time", hist_dimension, hist_dimension, "calls", unit, unit,
"name");
}
static void
DEFUN (print_line, (sym, scale), Sym * sym AND double scale)
{
if (ignore_zeros && sym->ncalls == 0 && sym->hist.time == 0)
{
return;
}
accum_time += sym->hist.time;
if (bsd_style_output)
{
printf ("%5.1f %10.2f %8.2f",
total_time > 0.0 ? 100 * sym->hist.time / total_time : 0.0,
accum_time / hz, sym->hist.time / hz);
}
else
{
printf ("%6.2f %9.2f %8.2f",
total_time > 0.0 ? 100 * sym->hist.time / total_time : 0.0,
accum_time / hz, sym->hist.time / hz);
}
if (sym->ncalls)
{
printf (" %8d %8.2f %8.2f ",
sym->ncalls, scale * sym->hist.time / hz / sym->ncalls,
scale * (sym->hist.time + sym->cg.child_time) / hz / sym->ncalls);
}
else
{
printf (" %8.8s %8.8s %8.8s ", "", "", "");
}
if (bsd_style_output)
{
print_name (sym);
}
else
{
print_name_only (sym);
}
printf ("\n");
}
/*
* Compare LP and RP. The primary comparison key is execution time,
* the secondary is number of invocation, and the tertiary is the
* lexicographic order of the function names.
*/
static int
DEFUN (cmp_time, (lp, rp), const PTR lp AND const PTR rp)
{
const Sym *left = *(const Sym **) lp;
const Sym *right = *(const Sym **) rp;
double time_diff;
long call_diff;
time_diff = right->hist.time - left->hist.time;
if (time_diff > 0.0)
{
return 1;
}
if (time_diff < 0.0)
{
return -1;
}
call_diff = right->ncalls - left->ncalls;
if (call_diff > 0)
{
return 1;
}
if (call_diff < 0)
{
return -1;
}
return strcmp (left->name, right->name);
}
/*
* Print the flat histogram profile.
*/
void
DEFUN_VOID (hist_print)
{
Sym **time_sorted_syms, *top_dog, *sym;
int index, log_scale;
double top_time, time;
bfd_vma addr;
if (first_output)
{
first_output = FALSE;
}
else
{
printf ("\f\n");
}
accum_time = 0.0;
if (bsd_style_output)
{
if (print_descriptions)
{
printf ("\n\n\nflat profile:\n");
flat_blurb (stdout);
}
}
else
{
printf ("Flat profile:\n");
}
/*
* Sort the symbol table by time (call-count and name as secondary
* and tertiary keys):
*/
time_sorted_syms = (Sym **) xmalloc (symtab.len * sizeof (Sym *));
for (index = 0; index < symtab.len; ++index)
{
time_sorted_syms[index] = &symtab.base[index];
}
qsort (time_sorted_syms, symtab.len, sizeof (Sym *), cmp_time);
if (bsd_style_output)
{
log_scale = 5; /* milli-seconds is BSD-default */
}
else
{
/*
* Search for symbol with highest per-call execution time and
* scale accordingly:
*/
log_scale = 0;
top_dog = 0;
top_time = 0.0;
for (index = 0; index < symtab.len; ++index)
{
sym = time_sorted_syms[index];
if (sym->ncalls)
{
time = (sym->hist.time + sym->cg.child_time) / sym->ncalls;
if (time > top_time)
{
top_dog = sym;
top_time = time;
}
}
}
if (top_dog && top_dog->ncalls && top_time > 0.0)
{
top_time /= hz;
while (SItab[log_scale].scale * top_time < 1000.0
&& log_scale < sizeof (SItab) / sizeof (SItab[0]) - 1)
{
++log_scale;
}
}
}
/*
* For now, the dimension is always seconds. In the future, we
* may also want to support other (pseudo-)dimensions (such as
* I-cache misses etc.).
*/
print_header (SItab[log_scale].prefix);
for (index = 0; index < symtab.len; ++index)
{
addr = time_sorted_syms[index]->addr;
/*
* Print symbol if its in INCL_FLAT table or that table
* is empty and the symbol is not in EXCL_FLAT.
*/
if (sym_lookup (&syms[INCL_FLAT], addr)
|| (syms[INCL_FLAT].len == 0
&& !sym_lookup (&syms[EXCL_FLAT], addr)))
{
print_line (time_sorted_syms[index], SItab[log_scale].scale);
}
}
free (time_sorted_syms);
if (print_descriptions && !bsd_style_output)
{
flat_blurb (stdout);
}
}