xref: /freebsd/contrib/llvm-project/compiler-rt/lib/stats/stats_client.cpp (revision 924226fba12cc9a228c73b956e1b7fa24c60b055)
1 //===-- stats_client.cpp --------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // Sanitizer statistics gathering. Manages statistics for a module (executable
10 // or DSO) and registers statistics with the process.
11 //
12 // This is linked into each individual modle and cannot directly use functions
13 // declared in sanitizer_common.
14 //
15 //===----------------------------------------------------------------------===//
16 
17 #ifdef _WIN32
18 #define WIN32_LEAN_AND_MEAN
19 #include <windows.h>
20 #else
21 #include <dlfcn.h>
22 #endif
23 #include <stdint.h>
24 #include <stdio.h>
25 
26 #include "sanitizer_common/sanitizer_internal_defs.h"
27 #include "stats/stats.h"
28 
29 using namespace __sanitizer;
30 
31 namespace {
32 
33 void *LookupSymbolFromMain(const char *name) {
34 #ifdef _WIN32
35   return reinterpret_cast<void *>(GetProcAddress(GetModuleHandle(0), name));
36 #else
37   return dlsym(RTLD_DEFAULT, name);
38 #endif
39 }
40 
41 StatModule *list;
42 
43 struct RegisterSanStats {
44   unsigned module_id;
45 
46   RegisterSanStats() {
47     typedef unsigned (*reg_func_t)(StatModule **);
48     reg_func_t reg_func = reinterpret_cast<reg_func_t>(
49         LookupSymbolFromMain("__sanitizer_stats_register"));
50     if (reg_func)
51       module_id = reg_func(&list);
52   }
53 
54   ~RegisterSanStats() {
55     typedef void (*unreg_func_t)(unsigned);
56     unreg_func_t unreg_func = reinterpret_cast<unreg_func_t>(
57         LookupSymbolFromMain("__sanitizer_stats_unregister"));
58     if (unreg_func)
59       unreg_func(module_id);
60   }
61 } reg;
62 
63 }
64 
65 extern "C" void __sanitizer_stat_init(StatModule *mod) {
66   mod->next = list;
67   list = mod;
68 }
69 
70 extern "C" void __sanitizer_stat_report(StatInfo *s) {
71   s->addr = GET_CALLER_PC();
72 #if defined(_WIN64) && !defined(__clang__)
73   uptr old_data = InterlockedIncrement64(reinterpret_cast<LONG64 *>(&s->data));
74 #elif defined(_WIN32) && !defined(__clang__)
75   uptr old_data = InterlockedIncrement(&s->data);
76 #else
77   uptr old_data = __sync_fetch_and_add(&s->data, 1);
78 #endif
79 
80   // Overflow check.
81   if (CountFromData(old_data + 1) == 0)
82     Trap();
83 }
84