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
19 static unsigned *ArrayStart;
20 static unsigned NumElements;
21
22 /* OptEdgeProfAtExitHandler - When the program exits, just write out the
23 * profiling data.
24 */
OptEdgeProfAtExitHandler(void)25 static 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 */
llvm_start_opt_edge_profiling(int argc,const char ** argv,unsigned * arrayStart,unsigned numElements)38 int 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