1 //===-- tsan_stack_trace.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 // This file is a part of ThreadSanitizer (TSan), a race detector.
10 //
11 //===----------------------------------------------------------------------===//
12 #include "tsan_stack_trace.h"
13 #include "tsan_rtl.h"
14 #include "tsan_mman.h"
15 
16 namespace __tsan {
17 
18 VarSizeStackTrace::VarSizeStackTrace()
19     : StackTrace(nullptr, 0), trace_buffer(nullptr) {}
20 
21 VarSizeStackTrace::~VarSizeStackTrace() {
22   ResizeBuffer(0);
23 }
24 
25 void VarSizeStackTrace::ResizeBuffer(uptr new_size) {
26   if (trace_buffer) {
27     internal_free(trace_buffer);
28   }
29   trace_buffer =
30       (new_size > 0)
31           ? (uptr *)internal_alloc(MBlockStackTrace,
32                                    new_size * sizeof(trace_buffer[0]))
33           : nullptr;
34   trace = trace_buffer;
35   size = new_size;
36 }
37 
38 void VarSizeStackTrace::Init(const uptr *pcs, uptr cnt, uptr extra_top_pc) {
39   ResizeBuffer(cnt + !!extra_top_pc);
40   internal_memcpy(trace_buffer, pcs, cnt * sizeof(trace_buffer[0]));
41   if (extra_top_pc)
42     trace_buffer[cnt] = extra_top_pc;
43 }
44 
45 void VarSizeStackTrace::ReverseOrder() {
46   for (u32 i = 0; i < (size >> 1); i++)
47     Swap(trace_buffer[i], trace_buffer[size - 1 - i]);
48 }
49 
50 }  // namespace __tsan
51 
52 #if !SANITIZER_GO
53 void __sanitizer::BufferedStackTrace::UnwindImpl(
54     uptr pc, uptr bp, void *context, bool request_fast, u32 max_depth) {
55   uptr top = 0;
56   uptr bottom = 0;
57   GetThreadStackTopAndBottom(false, &top, &bottom);
58   bool fast = StackTrace::WillUseFastUnwind(request_fast);
59   Unwind(max_depth, pc, bp, context, top, bottom, fast);
60 }
61 #endif  // SANITIZER_GO
62