1 //===- llvm/unittest/MC/DwarfLineTables.cpp ------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 #include "llvm/Support/Dwarf.h" 11 #include "llvm/ADT/STLExtras.h" 12 #include "llvm/MC/MCAsmInfo.h" 13 #include "llvm/MC/MCContext.h" 14 #include "llvm/MC/MCDwarf.h" 15 #include "llvm/MC/MCRegisterInfo.h" 16 #include "llvm/Support/TargetRegistry.h" 17 #include "llvm/Support/TargetSelect.h" 18 #include "gtest/gtest.h" 19 20 using namespace llvm; 21 22 namespace { 23 struct Context { 24 const char *Triple = "x86_64-pc-linux"; 25 std::unique_ptr<MCRegisterInfo> MRI; 26 std::unique_ptr<MCAsmInfo> MAI; 27 std::unique_ptr<MCContext> Ctx; 28 29 Context() { 30 llvm::InitializeAllTargetInfos(); 31 llvm::InitializeAllTargetMCs(); 32 llvm::InitializeAllDisassemblers(); 33 34 // If we didn't build x86, do not run the test. 35 std::string Error; 36 const Target *TheTarget = TargetRegistry::lookupTarget(Triple, Error); 37 if (!TheTarget) 38 return; 39 40 MRI.reset(TheTarget->createMCRegInfo(Triple)); 41 MAI.reset(TheTarget->createMCAsmInfo(*MRI, Triple)); 42 Ctx = llvm::make_unique<MCContext>(MAI.get(), MRI.get(), nullptr); 43 } 44 45 operator bool() { return Ctx.get(); } 46 operator MCContext &() { return *Ctx; }; 47 }; 48 49 Context Ctxt; 50 } 51 52 void verifyEncoding(MCDwarfLineTableParams Params, int LineDelta, int AddrDelta, 53 ArrayRef<uint8_t> ExpectedEncoding) { 54 SmallString<16> Buffer; 55 raw_svector_ostream EncodingOS(Buffer); 56 MCDwarfLineAddr::Encode(Ctxt, Params, LineDelta, AddrDelta, EncodingOS); 57 ArrayRef<uint8_t> Encoding(reinterpret_cast<uint8_t *>(Buffer.data()), 58 Buffer.size()); 59 EXPECT_EQ(ExpectedEncoding, Encoding); 60 } 61 62 TEST(DwarfLineTables, TestDefaultParams) { 63 if (!Ctxt) 64 return; 65 66 MCDwarfLineTableParams Params; 67 68 // Minimal line offset expressible through extended opcode, 0 addr delta 69 const uint8_t Encoding0[] = {13}; // Special opcode Addr += 0, Line += -5 70 verifyEncoding(Params, -5, 0, Encoding0); 71 72 // Maximal line offset expressible through extended opcode, 73 const uint8_t Encoding1[] = {26}; // Special opcode Addr += 0, Line += +8 74 verifyEncoding(Params, 8, 0, Encoding1); 75 76 // Random value in the middle of the special ocode range 77 const uint8_t Encoding2[] = {146}; // Special opcode Addr += 9, Line += 2 78 verifyEncoding(Params, 2, 9, Encoding2); 79 80 // Minimal line offset expressible through extended opcode, max addr delta 81 const uint8_t Encoding3[] = {251}; // Special opcode Addr += 17, Line += -5 82 verifyEncoding(Params, -5, 17, Encoding3); 83 84 // Biggest special opcode 85 const uint8_t Encoding4[] = {255}; // Special opcode Addr += 17, Line += -1 86 verifyEncoding(Params, -1, 17, Encoding4); 87 88 // Line delta outside of the special opcode range, address delta in range 89 const uint8_t Encoding5[] = {dwarf::DW_LNS_advance_line, 9, 90 158}; // Special opcode Addr += 10, Line += 0 91 verifyEncoding(Params, 9, 10, Encoding5); 92 93 // Address delta outside of the special opcode range, but small 94 // enough to do DW_LNS_const_add_pc + special opcode. 95 const uint8_t Encoding6[] = {dwarf::DW_LNS_const_add_pc, // pc += 17 96 62}; // Special opcode Addr += 3, Line += 2 97 verifyEncoding(Params, 2, 20, Encoding6); 98 99 // Address delta big enough to require the use of DW_LNS_advance_pc 100 // Line delta in special opcode range 101 const uint8_t Encoding7[] = {dwarf::DW_LNS_advance_pc, 100, 102 20}; // Special opcode Addr += 0, Line += 2 103 verifyEncoding(Params, 2, 100, Encoding7); 104 105 // No special opcode possible. 106 const uint8_t Encoding8[] = {dwarf::DW_LNS_advance_line, 20, 107 dwarf::DW_LNS_advance_pc, 100, 108 dwarf::DW_LNS_copy}; 109 verifyEncoding(Params, 20, 100, Encoding8); 110 } 111 112 TEST(DwarfLineTables, TestCustomParams) { 113 if (!Ctxt) 114 return; 115 116 // Some tests against the example values given in the standard. 117 MCDwarfLineTableParams Params; 118 Params.DWARF2LineOpcodeBase = 13; 119 Params.DWARF2LineBase = -3; 120 Params.DWARF2LineRange = 12; 121 122 // Minimal line offset expressible through extended opcode, 0 addr delta 123 const uint8_t Encoding0[] = {13}; // Special opcode Addr += 0, Line += -5 124 verifyEncoding(Params, -3, 0, Encoding0); 125 126 // Maximal line offset expressible through extended opcode, 127 const uint8_t Encoding1[] = {24}; // Special opcode Addr += 0, Line += +8 128 verifyEncoding(Params, 8, 0, Encoding1); 129 130 // Random value in the middle of the special ocode range 131 const uint8_t Encoding2[] = {126}; // Special opcode Addr += 9, Line += 2 132 verifyEncoding(Params, 2, 9, Encoding2); 133 134 // Minimal line offset expressible through extended opcode, max addr delta 135 const uint8_t Encoding3[] = {253}; // Special opcode Addr += 20, Line += -3 136 verifyEncoding(Params, -3, 20, Encoding3); 137 138 // Biggest special opcode 139 const uint8_t Encoding4[] = {255}; // Special opcode Addr += 17, Line += -1 140 verifyEncoding(Params, -1, 20, Encoding4); 141 142 // Line delta outside of the special opcode range, address delta in range 143 const uint8_t Encoding5[] = {dwarf::DW_LNS_advance_line, 9, 144 136}; // Special opcode Addr += 10, Line += 0 145 verifyEncoding(Params, 9, 10, Encoding5); 146 147 // Address delta outside of the special opcode range, but small 148 // enough to do DW_LNS_const_add_pc + special opcode. 149 const uint8_t Encoding6[] = {dwarf::DW_LNS_const_add_pc, // pc += 20 150 138}; // Special opcode Addr += 10, Line += 2 151 verifyEncoding(Params, 2, 30, Encoding6); 152 153 // Address delta big enough to require the use of DW_LNS_advance_pc 154 // Line delta in special opcode range 155 const uint8_t Encoding7[] = {dwarf::DW_LNS_advance_pc, 100, 156 18}; // Special opcode Addr += 0, Line += 2 157 verifyEncoding(Params, 2, 100, Encoding7); 158 159 // No special opcode possible. 160 const uint8_t Encoding8[] = {dwarf::DW_LNS_advance_line, 20, 161 dwarf::DW_LNS_advance_pc, 100, 162 dwarf::DW_LNS_copy}; 163 verifyEncoding(Params, 20, 100, Encoding8); 164 } 165 166 TEST(DwarfLineTables, TestCustomParams2) { 167 if (!Ctxt) 168 return; 169 170 // Corner case param values. 171 MCDwarfLineTableParams Params; 172 Params.DWARF2LineOpcodeBase = 13; 173 Params.DWARF2LineBase = 1; 174 Params.DWARF2LineRange = 255; 175 176 const uint8_t Encoding0[] = {dwarf::DW_LNS_advance_line, 248, 1, 177 dwarf::DW_LNS_copy}; 178 verifyEncoding(Params, 248, 0, Encoding0); 179 } 180
