From 5aa5d282eac56a21e74611c1cdbaa97bb5db2dca Mon Sep 17 00:00:00 2001 From: Vincent Ambo Date: Tue, 8 Feb 2022 02:05:36 +0300 Subject: chore(3p/abseil_cpp): unvendor abseil_cpp we weren't actually using these sources anymore, okay? Change-Id: If701571d9716de308d3512e1eb22c35db0877a66 Reviewed-on: https://cl.tvl.fyi/c/depot/+/5248 Tested-by: BuildkiteCI Reviewed-by: grfn Autosubmit: tazjin --- .../debugging/internal/stacktrace_aarch64-inl.inc | 199 --------------------- 1 file changed, 199 deletions(-) delete mode 100644 third_party/abseil_cpp/absl/debugging/internal/stacktrace_aarch64-inl.inc (limited to 'third_party/abseil_cpp/absl/debugging/internal/stacktrace_aarch64-inl.inc') diff --git a/third_party/abseil_cpp/absl/debugging/internal/stacktrace_aarch64-inl.inc b/third_party/abseil_cpp/absl/debugging/internal/stacktrace_aarch64-inl.inc deleted file mode 100644 index f4859d7c210a..000000000000 --- a/third_party/abseil_cpp/absl/debugging/internal/stacktrace_aarch64-inl.inc +++ /dev/null @@ -1,199 +0,0 @@ -#ifndef ABSL_DEBUGGING_INTERNAL_STACKTRACE_AARCH64_INL_H_ -#define ABSL_DEBUGGING_INTERNAL_STACKTRACE_AARCH64_INL_H_ - -// Generate stack tracer for aarch64 - -#if defined(__linux__) -#include -#include -#include -#endif - -#include -#include -#include -#include - -#include "absl/base/attributes.h" -#include "absl/debugging/internal/address_is_readable.h" -#include "absl/debugging/internal/vdso_support.h" // a no-op on non-elf or non-glibc systems -#include "absl/debugging/stacktrace.h" - -static const uintptr_t kUnknownFrameSize = 0; - -#if defined(__linux__) -// Returns the address of the VDSO __kernel_rt_sigreturn function, if present. -static const unsigned char* GetKernelRtSigreturnAddress() { - constexpr uintptr_t kImpossibleAddress = 1; - ABSL_CONST_INIT static std::atomic memoized{kImpossibleAddress}; - uintptr_t address = memoized.load(std::memory_order_relaxed); - if (address != kImpossibleAddress) { - return reinterpret_cast(address); - } - - address = reinterpret_cast(nullptr); - -#ifdef ABSL_HAVE_VDSO_SUPPORT - absl::debugging_internal::VDSOSupport vdso; - if (vdso.IsPresent()) { - absl::debugging_internal::VDSOSupport::SymbolInfo symbol_info; - auto lookup = [&](int type) { - return vdso.LookupSymbol("__kernel_rt_sigreturn", "LINUX_2.6.39", type, - &symbol_info); - }; - if ((!lookup(STT_FUNC) && !lookup(STT_NOTYPE)) || - symbol_info.address == nullptr) { - // Unexpected: VDSO is present, yet the expected symbol is missing - // or null. - assert(false && "VDSO is present, but doesn't have expected symbol"); - } else { - if (reinterpret_cast(symbol_info.address) != - kImpossibleAddress) { - address = reinterpret_cast(symbol_info.address); - } else { - assert(false && "VDSO returned invalid address"); - } - } - } -#endif - - memoized.store(address, std::memory_order_relaxed); - return reinterpret_cast(address); -} -#endif // __linux__ - -// Compute the size of a stack frame in [low..high). We assume that -// low < high. Return size of kUnknownFrameSize. -template -static inline uintptr_t ComputeStackFrameSize(const T* low, - const T* high) { - const char* low_char_ptr = reinterpret_cast(low); - const char* high_char_ptr = reinterpret_cast(high); - return low < high ? high_char_ptr - low_char_ptr : kUnknownFrameSize; -} - -// Given a pointer to a stack frame, locate and return the calling -// stackframe, or return null 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 -ABSL_ATTRIBUTE_NO_SANITIZE_ADDRESS // May read random elements from stack. -ABSL_ATTRIBUTE_NO_SANITIZE_MEMORY // May read random elements from stack. -static void **NextStackFrame(void **old_frame_pointer, const void *uc) { - void **new_frame_pointer = reinterpret_cast(*old_frame_pointer); - bool check_frame_size = true; - -#if defined(__linux__) - if (WITH_CONTEXT && uc != nullptr) { - // Check to see if next frame's return address is __kernel_rt_sigreturn. - if (old_frame_pointer[1] == GetKernelRtSigreturnAddress()) { - const ucontext_t *ucv = static_cast(uc); - // old_frame_pointer[0] is not suitable for unwinding, look at - // ucontext to discover frame pointer before signal. - void **const pre_signal_frame_pointer = - reinterpret_cast(ucv->uc_mcontext.regs[29]); - - // Check that alleged frame pointer is actually readable. This is to - // prevent "double fault" in case we hit the first fault due to e.g. - // stack corruption. - if (!absl::debugging_internal::AddressIsReadable( - pre_signal_frame_pointer)) - return nullptr; - - // Alleged frame pointer is readable, use it for further unwinding. - new_frame_pointer = pre_signal_frame_pointer; - - // Skip frame size check if we return from a signal. We may be using a - // an alternate stack for signals. - check_frame_size = false; - } - } -#endif - - // aarch64 ABI requires stack pointer to be 16-byte-aligned. - if ((reinterpret_cast(new_frame_pointer) & 15) != 0) - return nullptr; - - // Check frame size. In strict mode, we assume frames to be under - // 100,000 bytes. In non-strict mode, we relax the limit to 1MB. - if (check_frame_size) { - const uintptr_t max_size = STRICT_UNWINDING ? 100000 : 1000000; - const uintptr_t frame_size = - ComputeStackFrameSize(old_frame_pointer, new_frame_pointer); - if (frame_size == kUnknownFrameSize || frame_size > max_size) - return nullptr; - } - - return new_frame_pointer; -} - -template -ABSL_ATTRIBUTE_NO_SANITIZE_ADDRESS // May read random elements from stack. -ABSL_ATTRIBUTE_NO_SANITIZE_MEMORY // May read random elements from stack. -static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count, - const void *ucp, int *min_dropped_frames) { -#ifdef __GNUC__ - void **frame_pointer = reinterpret_cast(__builtin_frame_address(0)); -#else -# error reading stack point not yet supported on this platform. -#endif - - skip_count++; // Skip the frame for this function. - int n = 0; - - // The frame pointer points to low address of a frame. The first 64-bit - // word of a frame points to the next frame up the call chain, which normally - // is just after the high address of the current frame. The second word of - // a frame contains return adress of to the caller. To find a pc value - // associated with the current frame, we need to go down a level in the call - // chain. So we remember return the address of the last frame seen. This - // does not work for the first stack frame, which belongs to UnwindImp() but - // we skip the frame for UnwindImp() anyway. - void* prev_return_address = nullptr; - - while (frame_pointer && 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_frame_pointer = - NextStackFrame(frame_pointer, ucp); - - if (skip_count > 0) { - skip_count--; - } else { - result[n] = prev_return_address; - if (IS_STACK_FRAMES) { - sizes[n] = ComputeStackFrameSize(frame_pointer, next_frame_pointer); - } - n++; - } - prev_return_address = frame_pointer[1]; - frame_pointer = next_frame_pointer; - } - 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 (; frame_pointer != nullptr && j < kMaxUnwind; j++) { - frame_pointer = - NextStackFrame(frame_pointer, ucp); - } - *min_dropped_frames = j; - } - return n; -} - -namespace absl { -ABSL_NAMESPACE_BEGIN -namespace debugging_internal { -bool StackTraceWorksForTest() { - return true; -} -} // namespace debugging_internal -ABSL_NAMESPACE_END -} // namespace absl - -#endif // ABSL_DEBUGGING_INTERNAL_STACKTRACE_AARCH64_INL_H_ -- cgit 1.4.1