tvl-depot/absl/debugging/stacktrace.cc
Abseil Team cf6ab6bb2b Changes imported from Abseil "staging" branch:
- b527a3e4b36b644ac424e3c525b1cd393f6f6c40 Fix some typos in the usage examples by Jorg Brown <jorg@google.com>
  - 82be4a9adf3bb0ddafc0d46274969c99afffe870 Fix typo in optional.h comment. by Abseil Team <absl-team@google.com>
  - d6ee63bf8fc51fba074c23b33cebc28c808d7f07 Remove internal-only identifiers from code. by Daniel Katz <katzdm@google.com>
  - f9c3ad2f0d73f53b21603638af8b4bed636e79f4 Use easier understandable names for absl::StartsWith and ... by Abseil Team <absl-team@google.com>
  - 7c16c14fefee89c927b8789d6043c4691bcffc9b Add -Wno-missing-prototypes back to the LLVM copts. by Derek Mauro <dmauro@google.com>
  - 2f4b7d2e50c7023240242f1e15db60ccd7e8768d IWYU | absl/strings by Juemin Yang <jueminyang@google.com>
  - a99cbcc1daa34a2d6a2bb26de275e05173cc77e9 IWYU | absl/type by Juemin Yang <jueminyang@google.com>
  - 12e1146d0fc76c071d7e0ebaabb62f0a984fae66 Use LLVM_FLAGS and LLVM_TEST_FLAGS when --compiler=llvm. by Derek Mauro <dmauro@google.com>
  - cd6bea616abda558d0bace5bd77455662a233688 IWYU | absl/debugging by Juemin Yang <jueminyang@google.com>
  - d9a7382e59d46a8581b6b7a31cd5a48bb89326e9 IWYU | absl/synchronization by Juemin Yang <jueminyang@google.com>
  - 07ec7d6d5a4a666f4183c5d0ed9c342baa7b24bc IWYU | absl/numeric by Juemin Yang <jueminyang@google.com>
  - 12bfe40051f4270f8707e191af5652f83f2f750c Remove the RoundTrip{Float,Double}ToBuffer routines from ... by Jorg Brown <jorg@google.com>
  - eeb4fd67c9d97f66cb9475c3c5e51ab132f1c810 Adds conversion functions for converting between absl/tim... by Greg Miller <jgm@google.com>
  - 59a2108d05d4ea85dc5cc11e49b2cd2335d4295a Change Substitute to use %.6g formatting rather than 15/1... by Jorg Brown <jorg@google.com>
  - 394becb48e0fcd161642cdaac5120d32567e0ef8 IWYU | absl/meta by Juemin Yang <jueminyang@google.com>
  - 1e5da6e8da336699b2469dcf6dda025b9b0ec4c9 Rewrite atomic_hook.h to not use std::atomic<T*> under Wi... by Greg Falcon <gfalcon@google.com>

GitOrigin-RevId: b527a3e4b36b644ac424e3c525b1cd393f6f6c40
Change-Id: I14e331d91c956ef045ac7927091a9f179716de0c
2017-09-25 10:12:29 -04:00

133 lines
4.8 KiB
C++

// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Produce stack trace.
//
// There are three different ways we can try to get the stack trace:
//
// 1) Our hand-coded stack-unwinder. This depends on a certain stack
// layout, which is used by gcc (and those systems using a
// gcc-compatible ABI) on x86 systems, at least since gcc 2.95.
// It uses the frame pointer to do its work.
//
// 2) The libunwind library. This is still in development, and as a
// separate library adds a new dependency, but doesn't need a frame
// pointer. It also doesn't call malloc.
//
// 3) The gdb unwinder -- also the one used by the c++ exception code.
// It's obviously well-tested, but has a fatal flaw: it can call
// malloc() from the unwinder. This is a problem because we're
// trying to use the unwinder to instrument malloc().
//
// Note: if you add a new implementation here, make sure it works
// correctly when absl::GetStackTrace() is called with max_depth == 0.
// Some code may do that.
#include "absl/debugging/stacktrace.h"
#include <atomic>
#include "absl/base/attributes.h"
#include "absl/base/port.h"
#include "absl/debugging/internal/stacktrace_config.h"
#if defined(ABSL_STACKTRACE_INL_HEADER)
#include ABSL_STACKTRACE_INL_HEADER
#else
# error Cannot calculate stack trace: will need to write for your environment
# include "absl/debugging/internal/stacktrace_aarch64-inl.inc"
# include "absl/debugging/internal/stacktrace_arm-inl.inc"
# include "absl/debugging/internal/stacktrace_generic-inl.inc"
# include "absl/debugging/internal/stacktrace_powerpc-inl.inc"
# include "absl/debugging/internal/stacktrace_unimplemented-inl.inc"
# include "absl/debugging/internal/stacktrace_win32-inl.inc"
# include "absl/debugging/internal/stacktrace_x86-inl.inc"
#endif
namespace absl {
namespace {
typedef int (*Unwinder)(void**, int*, int, int, const void*, int*);
std::atomic<Unwinder> custom;
template <bool IS_STACK_FRAMES, bool IS_WITH_CONTEXT>
ABSL_ATTRIBUTE_ALWAYS_INLINE inline int Unwind(void** result, int* sizes,
int max_depth, int skip_count,
const void* uc,
int* min_dropped_frames) {
Unwinder f = &UnwindImpl<IS_STACK_FRAMES, IS_WITH_CONTEXT>;
Unwinder g = custom.load(std::memory_order_acquire);
if (g != nullptr) f = g;
// Add 1 to skip count for the unwinder function itself
int size = (*f)(result, sizes, max_depth, skip_count + 1, uc,
min_dropped_frames);
// To disable tail call to (*f)(...)
ABSL_BLOCK_TAIL_CALL_OPTIMIZATION();
return size;
}
} // anonymous namespace
int GetStackFrames(void** result, int* sizes, int max_depth, int skip_count) {
return Unwind<true, false>(result, sizes, max_depth, skip_count, nullptr,
nullptr);
}
int GetStackFramesWithContext(void** result, int* sizes, int max_depth,
int skip_count, const void* uc,
int* min_dropped_frames) {
return Unwind<true, true>(result, sizes, max_depth, skip_count, uc,
min_dropped_frames);
}
int GetStackTrace(void** result, int max_depth, int skip_count) {
return Unwind<false, false>(result, nullptr, max_depth, skip_count, nullptr,
nullptr);
}
int GetStackTraceWithContext(void** result, int max_depth, int skip_count,
const void* uc, int* min_dropped_frames) {
return Unwind<false, true>(result, nullptr, max_depth, skip_count, uc,
min_dropped_frames);
}
void SetStackUnwinder(Unwinder w) {
custom.store(w, std::memory_order_release);
}
int DefaultStackUnwinder(void** pcs, int* sizes, int depth, int skip,
const void* uc, int* min_dropped_frames) {
skip++; // For this function
Unwinder f = nullptr;
if (sizes == nullptr) {
if (uc == nullptr) {
f = &UnwindImpl<false, false>;
} else {
f = &UnwindImpl<false, true>;
}
} else {
if (uc == nullptr) {
f = &UnwindImpl<true, false>;
} else {
f = &UnwindImpl<true, true>;
}
}
volatile int x = 0;
int n = (*f)(pcs, sizes, depth, skip, uc, min_dropped_frames);
x = 1; (void) x; // To disable tail call to (*f)(...)
return n;
}
} // namespace absl