nsz Git - libfirm/blob - support/libfirmprof/instrument.c

   1 /**
   2  * Helper code to output instrumentation results
   3  *  @author Matthias Braun, Steven Schaefer
   4  */
   5 #include <stdio.h>
   6 #include <string.h>
   7 #include <stdlib.h>
   8
   9 /* Prevent the compiler from mangling the name of this function. */
  10 void __init_firmprof(const char*, unsigned int*, size_t)
  11      asm("__init_firmprof");
  12
  13 typedef struct _profile_counter_t {
  14         const char *filename;
  15         unsigned   *counters;
  16         unsigned    len;
  17         struct _profile_counter_t *next;
  18 } profile_counter_t;
  19
  20 static profile_counter_t *counters = NULL;
  21
  22 static void write_profiles(void)
  23 {
  24         profile_counter_t *counter = counters;
  25         while(counter != NULL) {
  26                 profile_counter_t *next = counter->next;
  27                 FILE *f = fopen(counter->filename, "wb");
  28                 if (f == NULL) {
  29                         perror("Warning: couldn't open file for writing profiling data");
  30                 } else {
  31                         fputs("firmprof", f);
  32                         fwrite(counter->counters, counter->len * sizeof(unsigned), 1, f);
  33                         fclose(f);
  34                 }
  35                 free(counter);
  36                 counter = next;
  37         }
  38 }
  39
  40 /**
  41  * Register a new profile counter. This is called by separate constructors
  42  * for each translation unit. Incidentally, referring to this function as
  43  * "__init_firmprof" is perfectly linker friendly.
  44  */
  45 void __init_firmprof(const char *filename,
  46                       unsigned int *counts, size_t len)
  47 {
  48         static int initialized = 0;
  49         profile_counter_t *counter;
  50
  51         if (!initialized) {
  52                 initialized = 1;
  53                 atexit(write_profiles);
  54         }
  55
  56         counter = (profile_counter_t*) malloc(sizeof(*counter));
  57         if (counter == NULL)
  58                 return;
  59
  60         counter->filename = filename;
  61         counter->counters = counts;
  62         counter->next     = counters;
  63         counter->len      = len;
  64
  65         counters = counter;
  66 }