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Diffstat (limited to 'third_party/abseil_cpp/absl/debugging/internal/stacktrace_arm-inl.inc')
| -rw-r--r-- | third_party/abseil_cpp/absl/debugging/internal/stacktrace_arm-inl.inc | 134 |
1 files changed, 0 insertions, 134 deletions
diff --git a/third_party/abseil_cpp/absl/debugging/internal/stacktrace_arm-inl.inc b/third_party/abseil_cpp/absl/debugging/internal/stacktrace_arm-inl.inc deleted file mode 100644 index 2a1bf2e886..0000000000 --- a/third_party/abseil_cpp/absl/debugging/internal/stacktrace_arm-inl.inc +++ /dev/null @@ -1,134 +0,0 @@ -// 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 -// -// https://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. -// -// This is inspired by Craig Silverstein's PowerPC stacktrace code. - -#ifndef ABSL_DEBUGGING_INTERNAL_STACKTRACE_ARM_INL_H_ -#define ABSL_DEBUGGING_INTERNAL_STACKTRACE_ARM_INL_H_ - -#include <cstdint> - -#include "absl/debugging/stacktrace.h" - -// WARNING: -// This only works if all your code is in either ARM or THUMB mode. With -// interworking, the frame pointer of the caller can either be in r11 (ARM -// mode) or r7 (THUMB mode). A callee only saves the frame pointer of its -// mode in a fixed location on its stack frame. If the caller is a different -// mode, there is no easy way to find the frame pointer. It can either be -// still in the designated register or saved on stack along with other callee -// saved registers. - -// Given a pointer to a stack frame, locate and return the calling -// stackframe, or return nullptr if no stackframe can be found. Perform sanity -// checks (the strictness of which is controlled by the boolean parameter -// "STRICT_UNWINDING") to reduce the chance that a bad pointer is returned. -template<bool STRICT_UNWINDING> -static void **NextStackFrame(void **old_sp) { - void **new_sp = (void**) old_sp[-1]; - - // Check that the transition from frame pointer old_sp to frame - // pointer new_sp isn't clearly bogus - if (STRICT_UNWINDING) { - // With the stack growing downwards, older stack frame must be - // at a greater address that the current one. - if (new_sp <= old_sp) return nullptr; - // Assume stack frames larger than 100,000 bytes are bogus. - if ((uintptr_t)new_sp - (uintptr_t)old_sp > 100000) return nullptr; - } else { - // In the non-strict mode, allow discontiguous stack frames. - // (alternate-signal-stacks for example). - if (new_sp == old_sp) return nullptr; - // And allow frames upto about 1MB. - if ((new_sp > old_sp) - && ((uintptr_t)new_sp - (uintptr_t)old_sp > 1000000)) return nullptr; - } - if ((uintptr_t)new_sp & (sizeof(void *) - 1)) return nullptr; - return new_sp; -} - -// This ensures that absl::GetStackTrace sets up the Link Register properly. -#ifdef __GNUC__ -void StacktraceArmDummyFunction() __attribute__((noinline)); -void StacktraceArmDummyFunction() { __asm__ volatile(""); } -#else -# error StacktraceArmDummyFunction() needs to be ported to this platform. -#endif - -template <bool IS_STACK_FRAMES, bool IS_WITH_CONTEXT> -static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count, - const void * /* ucp */, int *min_dropped_frames) { -#ifdef __GNUC__ - void **sp = reinterpret_cast<void**>(__builtin_frame_address(0)); -#else -# error reading stack point not yet supported on this platform. -#endif - - // On ARM, the return address is stored in the link register (r14). - // This is not saved on the stack frame of a leaf function. To - // simplify code that reads return addresses, we call a dummy - // function so that the return address of this function is also - // stored in the stack frame. This works at least for gcc. - StacktraceArmDummyFunction(); - - int n = 0; - while (sp && n < max_depth) { - // The absl::GetStackFrames routine is called when we are in some - // informational context (the failure signal handler for example). - // Use the non-strict unwinding rules to produce a stack trace - // that is as complete as possible (even if it contains a few bogus - // entries in some rare cases). - void **next_sp = NextStackFrame<!IS_STACK_FRAMES>(sp); - - if (skip_count > 0) { - skip_count--; - } else { - result[n] = *sp; - - if (IS_STACK_FRAMES) { - if (next_sp > sp) { - sizes[n] = (uintptr_t)next_sp - (uintptr_t)sp; - } else { - // A frame-size of 0 is used to indicate unknown frame size. - sizes[n] = 0; - } - } - n++; - } - sp = next_sp; - } - if (min_dropped_frames != nullptr) { - // Implementation detail: we clamp the max of frames we are willing to - // count, so as not to spend too much time in the loop below. - const int kMaxUnwind = 200; - int j = 0; - for (; sp != nullptr && j < kMaxUnwind; j++) { - sp = NextStackFrame<!IS_STACK_FRAMES>(sp); - } - *min_dropped_frames = j; - } - return n; -} - -namespace absl { -ABSL_NAMESPACE_BEGIN -namespace debugging_internal { -bool StackTraceWorksForTest() { - return false; -} -} // namespace debugging_internal -ABSL_NAMESPACE_END -} // namespace absl - -#endif // ABSL_DEBUGGING_INTERNAL_STACKTRACE_ARM_INL_H_ |