1/*===- InstrProfiling.c - Support library for PGO instrumentation ---------===*\
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#include "InstrProfiling.h"
11#include <string.h>
12
13__attribute__((visibility("hidden")))
14uint64_t __llvm_profile_get_magic(void) {
15  /* Magic number to detect file format and endianness.
16   *
17   * Use 255 at one end, since no UTF-8 file can use that character.  Avoid 0,
18   * so that utilities, like strings, don't grab it as a string.  129 is also
19   * invalid UTF-8, and high enough to be interesting.
20   *
21   * Use "lprofr" in the centre to stand for "LLVM Profile Raw", or "lprofR"
22   * for 32-bit platforms.
23   */
24  unsigned char R = sizeof(void *) == sizeof(uint64_t) ? 'r' : 'R';
25  return
26    (uint64_t)255 << 56 |
27    (uint64_t)'l' << 48 |
28    (uint64_t)'p' << 40 |
29    (uint64_t)'r' << 32 |
30    (uint64_t)'o' << 24 |
31    (uint64_t)'f' << 16 |
32    (uint64_t) R  <<  8 |
33    (uint64_t)129;
34}
35
36__attribute__((visibility("hidden")))
37uint64_t __llvm_profile_get_version(void) {
38  /* This should be bumped any time the output format changes. */
39  return 1;
40}
41
42__attribute__((visibility("hidden")))
43void __llvm_profile_reset_counters(void) {
44  uint64_t *I = __llvm_profile_begin_counters();
45  uint64_t *E = __llvm_profile_end_counters();
46
47  memset(I, 0, sizeof(uint64_t)*(E - I));
48}
49