llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-lldb Author: Miro Bucko (mbucko) <details> <summary>Changes</summary> Summary: Moving CommandObjectMemoryFind::FastSearch() to Process::FindInMemory(). Plan to expose FindInMemory as public API in SBProcess. Test Plan: ninja check-lldb Reviewers: clayborg Subscribers: Tasks: lldb Tags: --- Full diff: https://github.com/llvm/llvm-project/pull/93688.diff 3 Files Affected: - (modified) lldb/include/lldb/Target/Process.h (+22) - (modified) lldb/source/Commands/CommandObjectMemory.cpp (+2-59) - (modified) lldb/source/Target/Process.cpp (+55) ``````````diff diff --git a/lldb/include/lldb/Target/Process.h b/lldb/include/lldb/Target/Process.h index 637d34c29715c1..f293d1e78494f7 100644 --- a/lldb/include/lldb/Target/Process.h +++ b/lldb/include/lldb/Target/Process.h @@ -2663,6 +2663,28 @@ void PruneThreadPlans(); return m_source_file_cache; } + /// Find a pattern within a memory region. + /// + /// This function searches for a pattern represented by the provided buffer + /// within the memory range specified by the low and high addresses. It uses + /// a bad character heuristic to optimize the search process. + /// + /// \param[in] low The starting address of the memory region to be searched. + /// (inclusive) + /// + /// \param[in] high The ending address of the memory region to be searched. + /// (exclusive) + /// + /// \param[in] buf A pointer to the buffer containing the pattern to be + /// searched. + /// + /// \param[in] buffer_size The size of the buffer in bytes. + /// + /// \return The address where the pattern was found or LLDB_INVALID_ADDRESS if + /// not found. + lldb::addr_t FindInMemory(lldb::addr_t low, lldb::addr_t high, + const uint8_t *buf, size_t size); + protected: friend class Trace; diff --git a/lldb/source/Commands/CommandObjectMemory.cpp b/lldb/source/Commands/CommandObjectMemory.cpp index b78a0492cca558..1c13484dede648 100644 --- a/lldb/source/Commands/CommandObjectMemory.cpp +++ b/lldb/source/Commands/CommandObjectMemory.cpp @@ -977,35 +977,6 @@ class CommandObjectMemoryFind : public CommandObjectParsed { Options *GetOptions() override { return &m_option_group; } protected: - class ProcessMemoryIterator { - public: - ProcessMemoryIterator(ProcessSP process_sp, lldb::addr_t base) - : m_process_sp(process_sp), m_base_addr(base) { - lldbassert(process_sp.get() != nullptr); - } - - bool IsValid() { return m_is_valid; } - - uint8_t operator[](lldb::addr_t offset) { - if (!IsValid()) - return 0; - - uint8_t retval = 0; - Status error; - if (0 == - m_process_sp->ReadMemory(m_base_addr + offset, &retval, 1, error)) { - m_is_valid = false; - return 0; - } - - return retval; - } - - private: - ProcessSP m_process_sp; - lldb::addr_t m_base_addr; - bool m_is_valid = true; - }; void DoExecute(Args &command, CommandReturnObject &result) override { // No need to check "process" for validity as eCommandRequiresProcess // ensures it is valid @@ -1106,8 +1077,8 @@ class CommandObjectMemoryFind : public CommandObjectParsed { found_location = low_addr; bool ever_found = false; while (count) { - found_location = FastSearch(found_location, high_addr, buffer.GetBytes(), - buffer.GetByteSize()); + found_location = process->FindInMemory( + found_location, high_addr, buffer.GetBytes(), buffer.GetByteSize()); if (found_location == LLDB_INVALID_ADDRESS) { if (!ever_found) { result.AppendMessage("data not found within the range.\n"); @@ -1144,34 +1115,6 @@ class CommandObjectMemoryFind : public CommandObjectParsed { result.SetStatus(lldb::eReturnStatusSuccessFinishResult); } - lldb::addr_t FastSearch(lldb::addr_t low, lldb::addr_t high, uint8_t *buffer, - size_t buffer_size) { - const size_t region_size = high - low; - - if (region_size < buffer_size) - return LLDB_INVALID_ADDRESS; - - std::vector<size_t> bad_char_heuristic(256, buffer_size); - ProcessSP process_sp = m_exe_ctx.GetProcessSP(); - ProcessMemoryIterator iterator(process_sp, low); - - for (size_t idx = 0; idx < buffer_size - 1; idx++) { - decltype(bad_char_heuristic)::size_type bcu_idx = buffer[idx]; - bad_char_heuristic[bcu_idx] = buffer_size - idx - 1; - } - for (size_t s = 0; s <= (region_size - buffer_size);) { - int64_t j = buffer_size - 1; - while (j >= 0 && buffer[j] == iterator[s + j]) - j--; - if (j < 0) - return low + s; - else - s += bad_char_heuristic[iterator[s + buffer_size - 1]]; - } - - return LLDB_INVALID_ADDRESS; - } - OptionGroupOptions m_option_group; OptionGroupFindMemory m_memory_options; OptionGroupMemoryTag m_memory_tag_options; diff --git a/lldb/source/Target/Process.cpp b/lldb/source/Target/Process.cpp index 216d2f21abfef0..2e0a96b07b3d55 100644 --- a/lldb/source/Target/Process.cpp +++ b/lldb/source/Target/Process.cpp @@ -112,6 +112,34 @@ class ProcessOptionValueProperties } }; +class ProcessMemoryIterator { +public: + ProcessMemoryIterator(Process &process, lldb::addr_t base) + : m_process(process), m_base_addr(base) { } + + bool IsValid() { return m_is_valid; } + + uint8_t operator[](lldb::addr_t offset) { + if (!IsValid()) + return 0; + + uint8_t retval = 0; + Status error; + if (0 == + m_process.ReadMemory(m_base_addr + offset, &retval, 1, error)) { + m_is_valid = false; + return 0; + } + + return retval; + } + + private: + Process &m_process; + const lldb::addr_t m_base_addr; + bool m_is_valid = true; +}; + static constexpr OptionEnumValueElement g_follow_fork_mode_values[] = { { eFollowParent, @@ -3191,6 +3219,33 @@ Status Process::Halt(bool clear_thread_plans, bool use_run_lock) { return Status(); } +lldb::addr_t Process::FindInMemory(lldb::addr_t low, lldb::addr_t high, + const uint8_t *buf, size_t size) { + const size_t region_size = high - low; + + if (region_size < size) + return LLDB_INVALID_ADDRESS; + + std::vector<size_t> bad_char_heuristic(256, size); + ProcessMemoryIterator iterator(*this, low); + + for (size_t idx = 0; idx < size - 1; idx++) { + decltype(bad_char_heuristic)::size_type bcu_idx = buf[idx]; + bad_char_heuristic[bcu_idx] = size - idx - 1; + } + for (size_t s = 0; s <= (region_size - size);) { + int64_t j = size - 1; + while (j >= 0 && buf[j] == iterator[s + j]) + j--; + if (j < 0) + return low + s; + else + s += bad_char_heuristic[iterator[s + size - 1]]; + } + + return LLDB_INVALID_ADDRESS; +} + Status Process::StopForDestroyOrDetach(lldb::EventSP &exit_event_sp) { Status error; `````````` </details> https://github.com/llvm/llvm-project/pull/93688 _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
