1//===-- sanitizer_stacktrace_libcdep.cc -----------------------------------===//
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 is shared between AddressSanitizer and ThreadSanitizer
11// run-time libraries.
12//===----------------------------------------------------------------------===//
13
14#include "sanitizer_common.h"
15#include "sanitizer_placement_new.h"
16#include "sanitizer_stacktrace.h"
17#include "sanitizer_stacktrace_printer.h"
18#include "sanitizer_symbolizer.h"
19
20namespace __sanitizer {
21
22void StackTrace::Print() const {
23  if (trace == nullptr || size == 0) {
24    Printf("    <empty stack>\n\n");
25    return;
26  }
27  InternalScopedString frame_desc(GetPageSizeCached() * 2);
28  uptr frame_num = 0;
29  for (uptr i = 0; i < size && trace[i]; i++) {
30    // PCs in stack traces are actually the return addresses, that is,
31    // addresses of the next instructions after the call.
32    uptr pc = GetPreviousInstructionPc(trace[i]);
33    SymbolizedStack *frames = Symbolizer::GetOrInit()->SymbolizePC(pc);
34    CHECK(frames);
35    for (SymbolizedStack *cur = frames; cur; cur = cur->next) {
36      frame_desc.clear();
37      RenderFrame(&frame_desc, common_flags()->stack_trace_format, frame_num++,
38                  cur->info, common_flags()->symbolize_vs_style,
39                  common_flags()->strip_path_prefix);
40      Printf("%s\n", frame_desc.data());
41    }
42    frames->ClearAll();
43  }
44  // Always print a trailing empty line after stack trace.
45  Printf("\n");
46}
47
48void BufferedStackTrace::Unwind(u32 max_depth, uptr pc, uptr bp, void *context,
49                                uptr stack_top, uptr stack_bottom,
50                                bool request_fast_unwind) {
51  top_frame_bp = (max_depth > 0) ? bp : 0;
52  // Avoid doing any work for small max_depth.
53  if (max_depth == 0) {
54    size = 0;
55    return;
56  }
57  if (max_depth == 1) {
58    size = 1;
59    trace_buffer[0] = pc;
60    return;
61  }
62  if (!WillUseFastUnwind(request_fast_unwind)) {
63#if SANITIZER_CAN_SLOW_UNWIND
64    if (context)
65      SlowUnwindStackWithContext(pc, context, max_depth);
66    else
67      SlowUnwindStack(pc, max_depth);
68#else
69    UNREACHABLE("slow unwind requested but not available");
70#endif
71  } else {
72    FastUnwindStack(pc, bp, stack_top, stack_bottom, max_depth);
73  }
74}
75
76}  // namespace __sanitizer
77