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Merge pull request #3825 from augusto2112/move-lldb-memory-reader-next
[lldb] Move LLDBMemoryReader to its own file
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4 files changed

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‎lldb/source/Plugins/LanguageRuntime/Swift/CMakeLists.txt

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add_lldb_library(lldbPluginSwiftLanguageRuntime PLUGIN
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LLDBMemoryReader.cpp
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SwiftLanguageRuntime.cpp
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SwiftLanguageRuntimeDynamicTypeResolution.cpp
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SwiftLanguageRuntimeNames.cpp

‎lldb/source/Plugins/LanguageRuntime/Swift/LLDBMemoryReader.cpp

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#include "LLDBMemoryReader.h"
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#include "lldb/Core/Section.h"
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#include "lldb/Utility/Log.h"
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#include "lldb/Utility/Logging.h"
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using namespace lldb;
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using namespace lldb_private;
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namespace lldb_private {
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bool LLDBMemoryReader::queryDataLayout(DataLayoutQueryType type, void *inBuffer,
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void *outBuffer) {
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switch (type) {
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// FIXME: add support for case DLQ_GetPtrAuthMask rdar://70729149
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case DLQ_GetPtrAuthMask:
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return false;
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case DLQ_GetObjCReservedLowBits: {
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auto *result = static_cast<uint8_t *>(outBuffer);
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auto &triple = m_process.GetTarget().GetArchitecture().GetTriple();
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if (triple.isMacOSX() && triple.getArch() == llvm::Triple::x86_64) {
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// Obj-C reserves low bit on 64-bit Intel macOS only.
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// Other Apple platforms don't reserve this bit (even when
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// running on x86_64-based simulators).
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*result = 1;
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} else {
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*result = 0;
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}
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return true;
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}
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case DLQ_GetPointerSize: {
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auto *result = static_cast<uint8_t *>(outBuffer);
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*result = m_process.GetAddressByteSize();
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return true;
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}
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case DLQ_GetSizeSize: {
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auto *result = static_cast<uint8_t *>(outBuffer);
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*result = m_process.GetAddressByteSize(); // FIXME: sizeof(size_t)
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return true;
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}
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case DLQ_GetLeastValidPointerValue: {
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auto *result = (uint64_t *)outBuffer;
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auto &triple = m_process.GetTarget().GetArchitecture().GetTriple();
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if (triple.isOSDarwin() && triple.isArch64Bit())
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*result = 0x100000000;
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else
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*result = 0x1000;
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return true;
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}
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}
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}
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swift::remote::RemoteAddress
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LLDBMemoryReader::getSymbolAddress(const std::string &name) {
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lldbassert(!name.empty());
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if (name.empty())
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return swift::remote::RemoteAddress(nullptr);
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Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_TYPES));
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LLDB_LOGV(log, "[MemoryReader] asked to retrieve the address of symbol {0}",
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name);
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ConstString name_cs(name.c_str(), name.size());
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SymbolContextList sc_list;
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m_process.GetTarget().GetImages().FindSymbolsWithNameAndType(
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name_cs, lldb::eSymbolTypeAny, sc_list);
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if (!sc_list.GetSize()) {
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LLDB_LOGV(log, "[MemoryReader] symbol resolution failed {0}", name);
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return swift::remote::RemoteAddress(nullptr);
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}
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SymbolContext sym_ctx;
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// Remove undefined symbols from the list.
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size_t num_sc_matches = sc_list.GetSize();
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if (num_sc_matches > 1) {
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SymbolContextList tmp_sc_list(sc_list);
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sc_list.Clear();
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for (size_t idx = 0; idx < num_sc_matches; idx++) {
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tmp_sc_list.GetContextAtIndex(idx, sym_ctx);
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if (sym_ctx.symbol &&
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sym_ctx.symbol->GetType() != lldb::eSymbolTypeUndefined) {
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sc_list.Append(sym_ctx);
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}
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}
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}
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if (sc_list.GetSize() == 1 && sc_list.GetContextAtIndex(0, sym_ctx)) {
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if (sym_ctx.symbol) {
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auto load_addr = sym_ctx.symbol->GetLoadAddress(&m_process.GetTarget());
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LLDB_LOGV(log, "[MemoryReader] symbol resolved to {0:x}", load_addr);
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return swift::remote::RemoteAddress(load_addr);
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}
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}
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// Empty list, resolution failed.
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if (sc_list.GetSize() == 0) {
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LLDB_LOGV(log, "[MemoryReader] symbol resolution failed {0}", name);
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return swift::remote::RemoteAddress(nullptr);
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}
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// If there's a single symbol, then we're golden. If there's more than
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// a symbol, then just make sure all of them agree on the value.
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Status error;
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auto load_addr = sym_ctx.symbol->GetLoadAddress(&m_process.GetTarget());
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uint64_t sym_value = m_process.GetTarget().ReadUnsignedIntegerFromMemory(
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load_addr, m_process.GetAddressByteSize(), 0, error, true);
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for (unsigned i = 1; i < sc_list.GetSize(); ++i) {
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uint64_t other_sym_value =
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m_process.GetTarget().ReadUnsignedIntegerFromMemory(
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load_addr, m_process.GetAddressByteSize(), 0, error, true);
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if (sym_value != other_sym_value) {
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LLDB_LOGV(log, "[MemoryReader] symbol resolution failed {0}", name);
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return swift::remote::RemoteAddress(nullptr);
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}
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}
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LLDB_LOGV(log, "[MemoryReader] symbol resolved to {0}", load_addr);
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return swift::remote::RemoteAddress(load_addr);
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}
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bool LLDBMemoryReader::readBytes(swift::remote::RemoteAddress address,
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uint8_t *dest, uint64_t size) {
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if (m_local_buffer) {
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auto addr = address.getAddressData();
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if (addr >= *m_local_buffer &&
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addr + size <= *m_local_buffer + m_local_buffer_size) {
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// If this crashes, the assumptions stated in
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// GetDynamicTypeAndAddress_Protocol() most likely no longer
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// hold.
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memcpy(dest, (void *)addr, size);
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return true;
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}
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}
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Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_TYPES));
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LLDB_LOGV(log, "[MemoryReader] asked to read {0} bytes at address {1:x}",
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size, address.getAddressData());
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if (size > m_max_read_amount) {
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LLDB_LOGV(log, "[MemoryReader] memory read exceeds maximum allowed size");
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return false;
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}
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Target &target(m_process.GetTarget());
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Address addr(address.getAddressData());
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Status error;
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if (size > target.ReadMemory(addr, dest, size, error, true)) {
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LLDB_LOGV(log,
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"[MemoryReader] memory read returned fewer bytes than asked for");
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return false;
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}
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if (error.Fail()) {
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LLDB_LOGV(log, "[MemoryReader] memory read returned error: {0}",
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error.AsCString());
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return false;
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}
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auto format_data = [](auto dest, auto size) {
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StreamString stream;
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for (uint64_t i = 0; i < size; i++) {
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stream.PutHex8(dest[i]);
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stream.PutChar(' ');
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}
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return stream.GetData();
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};
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LLDB_LOGV(log, "[MemoryReader] memory read returned data: {0}",
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format_data(dest, size));
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return true;
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}
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bool LLDBMemoryReader::readString(swift::remote::RemoteAddress address,
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std::string &dest) {
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Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_TYPES));
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LLDB_LOGV(log, "[MemoryReader] asked to read string data at address {0:x}",
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address.getAddressData());
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Target &target(m_process.GetTarget());
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Address addr(address.getAddressData());
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Status error;
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target.ReadCStringFromMemory(addr, dest, error);
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if (error.Success()) {
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auto format_string = [](const std::string &dest) {
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StreamString stream;
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for (auto c : dest) {
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if (c >= 32 && c <= 127) {
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stream << c;
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} else {
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stream << "\\0";
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stream.PutHex8(c);
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}
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}
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return stream.GetData();
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};
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LLDB_LOGV(log, "[MemoryReader] memory read returned data: \"{0}\"",
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format_string(dest));
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return true;
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} else {
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LLDB_LOGV(log, "[MemoryReader] memory read returned error: {0}",
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error.AsCString());
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return false;
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}
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}
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void LLDBMemoryReader::pushLocalBuffer(uint64_t local_buffer,
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uint64_t local_buffer_size) {
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lldbassert(!m_local_buffer);
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m_local_buffer = local_buffer;
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m_local_buffer_size = local_buffer_size;
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}
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void LLDBMemoryReader::popLocalBuffer() {
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lldbassert(m_local_buffer);
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m_local_buffer.reset();
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m_local_buffer_size = 0;
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}
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} // namespace lldb_private

‎lldb/source/Plugins/LanguageRuntime/Swift/LLDBMemoryReader.h

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#ifndef liblldb_LLDBMemoryReader_h_
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#define liblldb_LLDBMemoryReader_h_
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#include "SwiftLanguageRuntime.h"
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#include "swift/Reflection/TypeLowering.h"
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#include "llvm/Support/Memory.h"
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namespace lldb_private {
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class LLDBMemoryReader : public swift::remote::MemoryReader {
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public:
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LLDBMemoryReader(Process &p, size_t max_read_amount = INT32_MAX)
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: m_process(p) {
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m_max_read_amount = max_read_amount;
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}
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virtual ~LLDBMemoryReader() = default;
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bool queryDataLayout(DataLayoutQueryType type, void *inBuffer,
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void *outBuffer) override;
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swift::remote::RemoteAddress
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getSymbolAddress(const std::string &name) override;
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bool readBytes(swift::remote::RemoteAddress address, uint8_t *dest,
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uint64_t size) override;
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bool readString(swift::remote::RemoteAddress address,
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std::string &dest) override;
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void pushLocalBuffer(uint64_t local_buffer, uint64_t local_buffer_size);
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void popLocalBuffer();
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private:
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Process &m_process;
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size_t m_max_read_amount;
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llvm::Optional<uint64_t> m_local_buffer;
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uint64_t m_local_buffer_size = 0;
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};
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} // namespace lldb_private
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#endif

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