Index: lldb/source/Expression/DWARFExpression.cpp =================================================================== --- lldb/source/Expression/DWARFExpression.cpp +++ lldb/source/Expression/DWARFExpression.cpp @@ -944,6 +944,80 @@ } } // namespace +/// Helper function to move common code used to resolve a file address and turn +/// into a load address. +/// +/// \param exe_ctx Pointer to the execution context +/// \param module_sp shared_ptr contains the module if we have one +/// \param error_ptr pointer to Status object if we have one +/// \param dw_op_type C-style string used to vary the error output +/// \param file_addr the file address we are trying to resolve and turn into a +/// load address +/// \param so_addr out parameter, will be set to load addresss or section offset +/// \param check_sectionoffset bool which determines if having a section offset +/// but not a load address is considerd a success +/// \returns llvm::Optional containing the load address if resolving and getting +/// the load address succeed or an empty Optinal otherwise. If +/// check_sectionoffset is true we consider LLDB_INVALID_ADDRESS a +/// success if so_addr.IsSectionOffset() is true. +static llvm::Optional +ResolveAndLoadFileAddress(ExecutionContext *exe_ctx, lldb::ModuleSP module_sp, + Status *error_ptr, const char *dw_op_type, + lldb::addr_t file_addr, Address &so_addr, + bool check_sectionoffset = false) { + if (!module_sp) { + if (error_ptr) + error_ptr->SetErrorStringWithFormat( + "need module to resolve file address for %s", dw_op_type); + return {}; + } + + if (!module_sp->ResolveFileAddress(file_addr, so_addr)) { + if (error_ptr) + error_ptr->SetErrorString("failed to resolve file address in module"); + return {}; + } + + addr_t load_addr = so_addr.GetLoadAddress(exe_ctx->GetTargetPtr()); + + if (load_addr == LLDB_INVALID_ADDRESS && + (check_sectionoffset && !so_addr.IsSectionOffset())) { + if (error_ptr) + error_ptr->SetErrorString("failed to resolve load address"); + return {}; + } + + return load_addr; +} + +/// Helper function to move common code used to load sized data from a uint8_t +/// buffer. +/// +/// \param addr_bytes uint8_t buffer containg raw data +/// \param size_addr_bytes how large is the underlying raw data +/// \param byte_order what is the byter order of the underlyig data +/// \param size How much of the underlying data we want to use +/// \return The underlying data converted into a Scalar +static Scalar DerefSizeExtractDataHelper(uint8_t *addr_bytes, + size_t size_addr_bytes, + ByteOrder byte_order, size_t size) { + DataExtractor addr_data(addr_bytes, size_addr_bytes, byte_order, size); + + lldb::offset_t addr_data_offset = 0; + switch (size) { + case 1: + return addr_data.GetU8(&addr_data_offset); + case 2: + return addr_data.GetU16(&addr_data_offset); + case 4: + return addr_data.GetU32(&addr_data_offset); + case 8: + return addr_data.GetU64(&addr_data_offset); + default: + return addr_data.GetAddress(&addr_data_offset); + } +} + bool DWARFExpression::Evaluate( ExecutionContext *exe_ctx, RegisterContext *reg_ctx, lldb::ModuleSP module_sp, const DataExtractor &opcodes, @@ -1026,6 +1100,7 @@ if (frame) stack.back().ConvertToLoadAddress(module_sp.get(), frame->CalculateTarget().get()); + break; // The DW_OP_addr_sect_offset4 is used for any location expressions in @@ -1089,26 +1164,15 @@ case Value::ValueType::FileAddress: { auto file_addr = stack.back().GetScalar().ULongLong( LLDB_INVALID_ADDRESS); - if (!module_sp) { - if (error_ptr) - error_ptr->SetErrorString( - "need module to resolve file address for DW_OP_deref"); - return false; - } + Address so_addr; - if (!module_sp->ResolveFileAddress(file_addr, so_addr)) { - if (error_ptr) - error_ptr->SetErrorString( - "failed to resolve file address in module"); - return false; - } - addr_t load_Addr = so_addr.GetLoadAddress(exe_ctx->GetTargetPtr()); - if (load_Addr == LLDB_INVALID_ADDRESS) { - if (error_ptr) - error_ptr->SetErrorString("failed to resolve load address"); + auto maybe_load_addr = ResolveAndLoadFileAddress( + exe_ctx, module_sp, error_ptr, "DW_OP_deref", file_addr, so_addr); + + if (!maybe_load_addr) return false; - } - stack.back().GetScalar() = load_Addr; + + stack.back().GetScalar() = *maybe_load_addr; // Fall through to load address promotion code below. } LLVM_FALLTHROUGH; case Value::ValueType::Scalar: @@ -1219,6 +1283,47 @@ stack.back().GetScalar() = ptr; stack.back().ClearContext(); } break; + case Value::ValueType::FileAddress: { + auto file_addr = + stack.back().GetScalar().ULongLong(LLDB_INVALID_ADDRESS); + Address so_addr; + auto maybe_load_addr = + ResolveAndLoadFileAddress(exe_ctx, module_sp, error_ptr, + "DW_OP_deref_size", file_addr, so_addr, + /*check_sectionoffset=*/true); + + if (!maybe_load_addr) + return false; + + addr_t load_addr = *maybe_load_addr; + + if (load_addr == LLDB_INVALID_ADDRESS && so_addr.IsSectionOffset()) { + uint8_t addr_bytes[size]; + Status error; + + if (exe_ctx->GetTargetRef().ReadMemory( + so_addr, &addr_bytes, size, error, + /*force_live_memory=*/false) == size) { + ObjectFile *objfile = module_sp->GetObjectFile(); + + stack.back().GetScalar() = DerefSizeExtractDataHelper( + addr_bytes, sizeof(addr_bytes), objfile->GetByteOrder(), size); + stack.back().ClearContext(); + break; + } else { + if (error_ptr) + error_ptr->SetErrorStringWithFormat( + "Failed to dereference pointer for for DW_OP_deref_size: " + "%s\n", + error.AsCString()); + return false; + } + } + stack.back().GetScalar() = load_addr; + // Fall through to load address promotion code below. + } + + LLVM_FALLTHROUGH; case Value::ValueType::Scalar: case Value::ValueType::LoadAddress: if (exe_ctx) { @@ -1229,26 +1334,10 @@ Status error; if (process->ReadMemory(pointer_addr, &addr_bytes, size, error) == size) { - DataExtractor addr_data(addr_bytes, sizeof(addr_bytes), - process->GetByteOrder(), size); - lldb::offset_t addr_data_offset = 0; - switch (size) { - case 1: - stack.back().GetScalar() = addr_data.GetU8(&addr_data_offset); - break; - case 2: - stack.back().GetScalar() = addr_data.GetU16(&addr_data_offset); - break; - case 4: - stack.back().GetScalar() = addr_data.GetU32(&addr_data_offset); - break; - case 8: - stack.back().GetScalar() = addr_data.GetU64(&addr_data_offset); - break; - default: - stack.back().GetScalar() = - addr_data.GetAddress(&addr_data_offset); - } + + stack.back().GetScalar() = + DerefSizeExtractDataHelper(addr_bytes, sizeof(addr_bytes), + process->GetByteOrder(), size); stack.back().ClearContext(); } else { if (error_ptr) @@ -1271,7 +1360,7 @@ } break; - case Value::ValueType::FileAddress: + // case Value::ValueType::FileAddress: case Value::ValueType::Invalid: if (error_ptr) error_ptr->SetErrorString("Invalid value for DW_OP_deref_size.\n"); Index: lldb/test/Shell/SymbolFile/DWARF/x86/DW_OP_deref_size_static_var.s =================================================================== --- lldb/test/Shell/SymbolFile/DWARF/x86/DW_OP_deref_size_static_var.s +++ lldb/test/Shell/SymbolFile/DWARF/x86/DW_OP_deref_size_static_var.s @@ -3,7 +3,7 @@ # CHECK: (lldb) target variable ug # CHECK: (U) ug = { -# CHECK: raw = 0 +# CHECK: raw = 0 # CHECK: = (a = 0, b = 0, c = 0, d = 0, e = 0, f = 0) # CHECK: } @@ -48,7 +48,7 @@ # clang -O1 -gdwarf-4 dw_op_deref_size_test.c -S -o dw_op_deref_size_test.s # # Hand modified .s file to remoce various section that are not needed for this -# test +# test .zerofill __DATA,__bss,_ug.0,1,2 ## @ug.0 .zerofill __DATA,__bss,__type_anchor,4,2 ## @_type_anchor @@ -199,7 +199,7 @@ .long 105 ## DW_AT_name .long 129 ## DW_AT_LLVM_sysroot .long 185 ## DW_AT_APPLE_sdk - .long 0 + .long 0 .long 200 ## DW_AT_comp_dir ## DW_AT_APPLE_optimized .byte 2 ## Abbrev [2] 0x26:0x15 DW_TAG_variable