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-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "lldb/Core/DumpRegisterValue.h" 10 #include "lldb/Core/DumpDataExtractor.h" 11 #include "lldb/Core/ValueObject.h" 12 #include "lldb/Core/ValueObjectConstResult.h" 13 #include "lldb/DataFormatters/DumpValueObjectOptions.h" 14 #include "lldb/Target/RegisterFlags.h" 15 #include "lldb/Utility/DataExtractor.h" 16 #include "lldb/Utility/Endian.h" 17 #include "lldb/Utility/RegisterValue.h" 18 #include "lldb/Utility/StreamString.h" 19 #include "lldb/lldb-private-types.h" 20 #include "llvm/ADT/bit.h" 21 22 using namespace lldb; 23 24 template <typename T> 25 static 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 are 32 // 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 print 34 // them. On a big endian host this all matches up, for a little endian 35 // 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 vobj_sp->Dump(strm, dump_options); 58 } 59 60 void lldb_private::DumpRegisterValue(const RegisterValue ®_val, Stream &s, 61 const RegisterInfo ®_info, 62 bool prefix_with_name, 63 bool prefix_with_alt_name, Format format, 64 uint32_t reg_name_right_align_at, 65 ExecutionContextScope *exe_scope, 66 bool print_flags, TargetSP target_sp) { 67 DataExtractor data; 68 if (!reg_val.GetData(data)) 69 return; 70 71 bool name_printed = false; 72 // For simplicity, alignment of the register name printing applies only in 73 // the most common case where: 74 // 75 // prefix_with_name^prefix_with_alt_name is true 76 // 77 StreamString format_string; 78 if (reg_name_right_align_at && (prefix_with_name ^ prefix_with_alt_name)) 79 format_string.Printf("%%%us", reg_name_right_align_at); 80 else 81 format_string.Printf("%%s"); 82 std::string fmt = std::string(format_string.GetString()); 83 if (prefix_with_name) { 84 if (reg_info.name) { 85 s.Printf(fmt.c_str(), reg_info.name); 86 name_printed = true; 87 } else if (reg_info.alt_name) { 88 s.Printf(fmt.c_str(), reg_info.alt_name); 89 prefix_with_alt_name = false; 90 name_printed = true; 91 } 92 } 93 if (prefix_with_alt_name) { 94 if (name_printed) 95 s.PutChar('/'); 96 if (reg_info.alt_name) { 97 s.Printf(fmt.c_str(), reg_info.alt_name); 98 name_printed = true; 99 } else if (!name_printed) { 100 // No alternate name but we were asked to display a name, so show the 101 // main name 102 s.Printf(fmt.c_str(), reg_info.name); 103 name_printed = true; 104 } 105 } 106 if (name_printed) 107 s.PutCString(" = "); 108 109 if (format == eFormatDefault) 110 format = reg_info.format; 111 112 DumpDataExtractor(data, &s, 113 0, // Offset in "data" 114 format, // Format to use when dumping 115 reg_info.byte_size, // item_byte_size 116 1, // item_count 117 UINT32_MAX, // num_per_line 118 LLDB_INVALID_ADDRESS, // base_addr 119 0, // item_bit_size 120 0, // item_bit_offset 121 exe_scope); 122 123 if (!print_flags || !reg_info.flags_type || !exe_scope || !target_sp || 124 (reg_info.byte_size != 4 && reg_info.byte_size != 8)) 125 return; 126 127 CompilerType fields_type = target_sp->GetRegisterType( 128 reg_info.name, *reg_info.flags_type, reg_info.byte_size); 129 130 // Use a new stream so we can remove a trailing newline later. 131 StreamString fields_stream; 132 133 if (reg_info.byte_size == 4) { 134 dump_type_value(fields_type, reg_val.GetAsUInt32(), exe_scope, reg_info, 135 fields_stream); 136 } else { 137 dump_type_value(fields_type, reg_val.GetAsUInt64(), exe_scope, reg_info, 138 fields_stream); 139 } 140 141 // Registers are indented like: 142 // (lldb) register read foo 143 // foo = 0x12345678 144 // So we need to indent to match that. 145 146 // First drop the extra newline that the value printer added. The register 147 // command will add one itself. 148 llvm::StringRef fields_str = fields_stream.GetString().drop_back(); 149 150 // End the line that contains " foo = 0x12345678". 151 s.EOL(); 152 153 // Then split the value lines and indent each one. 154 bool first = true; 155 while (fields_str.size()) { 156 std::pair<llvm::StringRef, llvm::StringRef> split = fields_str.split('\n'); 157 fields_str = split.second; 158 // Indent as far as the register name did. 159 s.Printf(fmt.c_str(), ""); 160 161 // Lines after the first won't have " = " so compensate for that. 162 if (!first) 163 s << " "; 164 first = false; 165 166 s << split.first; 167 168 // On the last line we don't want a newline because the command will add 169 // one too. 170 if (fields_str.size()) 171 s.EOL(); 172 } 173 } 174