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Diffstat (limited to 'deps/v8/src/trap-handler/trap-handler-internal.h')
-rw-r--r-- | deps/v8/src/trap-handler/trap-handler-internal.h | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/deps/v8/src/trap-handler/trap-handler-internal.h b/deps/v8/src/trap-handler/trap-handler-internal.h new file mode 100644 index 0000000000..b4efd7ff9e --- /dev/null +++ b/deps/v8/src/trap-handler/trap-handler-internal.h @@ -0,0 +1,67 @@ +// Copyright 2016 the V8 project authors. All rights reserved. +// Use of this source code is governed by a BSD-style license that can be +// found in the LICENSE file. + +#ifndef TRAP_HANDLER_INTERNAL_H_ +#define TRAP_HANDLER_INTERNAL_H_ + +// This file should not be included (even transitively) by files outside of +// src/trap-handler. + +#include "src/trap-handler/trap-handler.h" + +#include <atomic> + +namespace v8 { +namespace internal { +namespace trap_handler { + +// This describes a chunk of code that the signal handler will be able to handle +// faults in. {base} points to the beginning of the chunk, and {size} is the +// number of bytes in the code chunk. The remainder of the struct is a list of +// protected memory access instructions and an offset to a landing pad to handle +// faults on that instruction. +struct CodeProtectionInfo { + void* base; + size_t size; + size_t num_protected_instructions; + ProtectedInstructionData instructions[1]; +}; + +class MetadataLock { + static std::atomic_flag spinlock_; + + public: + MetadataLock(); + ~MetadataLock(); + + // We'd normally use DISALLOW_COPY_AND_ASSIGN, but we're avoiding a dependency + // on base/macros.h + MetadataLock(const MetadataLock&) = delete; + void operator=(const MetadataLock&) = delete; +}; + +#if V8_TRAP_HANDLER_SUPPORTED +void HandleSignal(int signum, siginfo_t* info, void* context); +#endif + +// To enable constant time registration of handler data, we keep a free list of +// entries in the gCodeObjects table. Each entry contains a {next_free} field, +// which can be used to figure out where the next entry should be inserted. +// In order to avoid having to initialize all the links to start with, we use +// 0 to indicate that this is a fresh, never-used list entry and that therefore +// the next entry is known to be free. If {next_entry} is greater than zero, +// then {next_entry - 1} is the index that we should insert into next. +struct CodeProtectionInfoListEntry { + CodeProtectionInfo* code_info; + size_t next_free; +}; + +extern size_t gNumCodeObjects; +extern CodeProtectionInfoListEntry* gCodeObjects; + +} // namespace trap_handler +} // namespace internal +} // namespace v8 + +#endif // TRAP_HANDLER_INTERNAL_H_ |