175 lines · cpp
1//===-- DumpRegisterValue.cpp ---------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "lldb/Core/DumpRegisterValue.h"10#include "lldb/Core/DumpDataExtractor.h"11#include "lldb/DataFormatters/DumpValueObjectOptions.h"12#include "lldb/Target/RegisterFlags.h"13#include "lldb/Utility/DataExtractor.h"14#include "lldb/Utility/Endian.h"15#include "lldb/Utility/RegisterValue.h"16#include "lldb/Utility/StreamString.h"17#include "lldb/ValueObject/ValueObject.h"18#include "lldb/ValueObject/ValueObjectConstResult.h"19#include "lldb/lldb-private-types.h"20#include "llvm/ADT/bit.h"21 22using namespace lldb;23 24template <typename T>25static void dump_type_value(lldb_private::CompilerType &fields_type, T value,26 lldb_private::ExecutionContextScope *exe_scope,27 const lldb_private::RegisterInfo ®_info,28 lldb_private::Stream &strm) {29 lldb::ByteOrder target_order = exe_scope->CalculateProcess()->GetByteOrder();30 31 // For the bitfield types we generate, it is expected that the fields are32 // in what is usually a big endian order. Most significant field first.33 // This is also clang's internal ordering and the order we want to print34 // them. On a big endian host this all matches up, for a little endian35 // host we have to swap the order of the fields before display.36 if (target_order == lldb::ByteOrder::eByteOrderLittle) {37 value = reg_info.flags_type->ReverseFieldOrder(value);38 }39 40 // Then we need to match the target's endian on a byte level as well.41 if (lldb_private::endian::InlHostByteOrder() != target_order)42 value = llvm::byteswap(value);43 44 lldb_private::DataExtractor data_extractor{45 &value, sizeof(T), lldb_private::endian::InlHostByteOrder(), 8};46 47 lldb::ValueObjectSP vobj_sp = lldb_private::ValueObjectConstResult::Create(48 exe_scope, fields_type, lldb_private::ConstString(), data_extractor);49 lldb_private::DumpValueObjectOptions dump_options;50 lldb_private::DumpValueObjectOptions::ChildPrintingDecider decider =51 [](lldb_private::ConstString varname) {52 // Unnamed bit-fields are padding that we don't want to show.53 return varname.GetLength();54 };55 dump_options.SetChildPrintingDecider(decider).SetHideRootType(true);56 57 if (llvm::Error error = vobj_sp->Dump(strm, dump_options))58 strm << "error: " << toString(std::move(error));59}60 61void lldb_private::DumpRegisterValue(const RegisterValue ®_val, Stream &s,62 const RegisterInfo ®_info,63 bool prefix_with_name,64 bool prefix_with_alt_name, Format format,65 uint32_t reg_name_right_align_at,66 ExecutionContextScope *exe_scope,67 bool print_flags, TargetSP target_sp) {68 DataExtractor data;69 if (!reg_val.GetData(data))70 return;71 72 bool name_printed = false;73 // For simplicity, alignment of the register name printing applies only in74 // the most common case where:75 //76 // prefix_with_name^prefix_with_alt_name is true77 //78 StreamString format_string;79 if (reg_name_right_align_at && (prefix_with_name ^ prefix_with_alt_name))80 format_string.Printf("%%%us", reg_name_right_align_at);81 else82 format_string.Printf("%%s");83 std::string fmt = std::string(format_string.GetString());84 if (prefix_with_name) {85 if (reg_info.name) {86 s.Printf(fmt.c_str(), reg_info.name);87 name_printed = true;88 } else if (reg_info.alt_name) {89 s.Printf(fmt.c_str(), reg_info.alt_name);90 prefix_with_alt_name = false;91 name_printed = true;92 }93 }94 if (prefix_with_alt_name) {95 if (name_printed)96 s.PutChar('/');97 if (reg_info.alt_name) {98 s.Printf(fmt.c_str(), reg_info.alt_name);99 name_printed = true;100 } else if (!name_printed) {101 // No alternate name but we were asked to display a name, so show the102 // main name103 s.Printf(fmt.c_str(), reg_info.name);104 name_printed = true;105 }106 }107 if (name_printed)108 s.PutCString(" = ");109 110 if (format == eFormatDefault)111 format = reg_info.format;112 113 DumpDataExtractor(data, &s,114 0, // Offset in "data"115 format, // Format to use when dumping116 reg_info.byte_size, // item_byte_size117 1, // item_count118 UINT32_MAX, // num_per_line119 LLDB_INVALID_ADDRESS, // base_addr120 0, // item_bit_size121 0, // item_bit_offset122 exe_scope);123 124 if (!print_flags || !reg_info.flags_type || !exe_scope || !target_sp ||125 (reg_info.byte_size != 4 && reg_info.byte_size != 8))126 return;127 128 CompilerType fields_type = target_sp->GetRegisterType(129 reg_info.name, *reg_info.flags_type, reg_info.byte_size);130 131 // Use a new stream so we can remove a trailing newline later.132 StreamString fields_stream;133 134 if (reg_info.byte_size == 4) {135 dump_type_value(fields_type, reg_val.GetAsUInt32(), exe_scope, reg_info,136 fields_stream);137 } else {138 dump_type_value(fields_type, reg_val.GetAsUInt64(), exe_scope, reg_info,139 fields_stream);140 }141 142 // Registers are indented like:143 // (lldb) register read foo144 // foo = 0x12345678145 // So we need to indent to match that.146 147 // First drop the extra newline that the value printer added. The register148 // command will add one itself.149 llvm::StringRef fields_str = fields_stream.GetString().drop_back();150 151 // End the line that contains " foo = 0x12345678".152 s.EOL();153 154 // Then split the value lines and indent each one.155 bool first = true;156 while (fields_str.size()) {157 std::pair<llvm::StringRef, llvm::StringRef> split = fields_str.split('\n');158 fields_str = split.second;159 // Indent as far as the register name did.160 s.Printf(fmt.c_str(), "");161 162 // Lines after the first won't have " = " so compensate for that.163 if (!first)164 s << " ";165 first = false;166 167 s << split.first;168 169 // On the last line we don't want a newline because the command will add170 // one too.171 if (fields_str.size())172 s.EOL();173 }174}175