1/*===-- OptimalEdgeProfiling.c - Support library for opt. edge profiling --===*\
2|*
3|*                     The LLVM Compiler Infrastructure
4|*
5|* This file is distributed under the University of Illinois Open Source
6|* License. See LICENSE.TXT for details.
7|*
8|*===----------------------------------------------------------------------===*|
9|*
10|* This file implements the call back routines for the edge profiling
11|* instrumentation pass.  This should be used with the
12|* -insert-opt-edge-profiling LLVM pass.
13|*
14\*===----------------------------------------------------------------------===*/
15
16#include "Profiling.h"
17#include <stdlib.h>
18
19static unsigned *ArrayStart;
20static unsigned NumElements;
21
22/* OptEdgeProfAtExitHandler - When the program exits, just write out the
23 * profiling data.
24 */
25static void OptEdgeProfAtExitHandler(void) {
26  /* Note that, although the array has a counter for each edge, not all
27   * counters are updated, the ones that are not used are initialised with -1.
28   * When loading this information the counters with value -1 have to be
29   * recalculated, it is guaranteed that this is possible.
30   */
31  write_profiling_data(OptEdgeInfo, ArrayStart, NumElements);
32}
33
34
35/* llvm_start_opt_edge_profiling - This is the main entry point of the edge
36 * profiling library.  It is responsible for setting up the atexit handler.
37 */
38int llvm_start_opt_edge_profiling(int argc, const char **argv,
39                                  unsigned *arrayStart, unsigned numElements) {
40  int Ret = save_arguments(argc, argv);
41  ArrayStart = arrayStart;
42  NumElements = numElements;
43  atexit(OptEdgeProfAtExitHandler);
44  return Ret;
45}
46