1 //===-- MSP430AsmPrinter.cpp - MSP430 LLVM assembly writer ----------------===// 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 // This file contains a printer that converts from our internal representation 10 // of machine-dependent LLVM code to the MSP430 assembly language. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "MCTargetDesc/MSP430InstPrinter.h" 15 #include "MSP430MCInstLower.h" 16 #include "MSP430TargetMachine.h" 17 #include "TargetInfo/MSP430TargetInfo.h" 18 #include "llvm/BinaryFormat/ELF.h" 19 #include "llvm/CodeGen/AsmPrinter.h" 20 #include "llvm/CodeGen/MachineConstantPool.h" 21 #include "llvm/CodeGen/MachineInstr.h" 22 #include "llvm/CodeGen/MachineModuleInfo.h" 23 #include "llvm/IR/Mangler.h" 24 #include "llvm/MC/MCAsmInfo.h" 25 #include "llvm/MC/MCInst.h" 26 #include "llvm/MC/MCSectionELF.h" 27 #include "llvm/MC/MCStreamer.h" 28 #include "llvm/MC/MCSymbol.h" 29 #include "llvm/MC/TargetRegistry.h" 30 #include "llvm/Support/Compiler.h" 31 #include "llvm/Support/raw_ostream.h" 32 using namespace llvm; 33 34 #define DEBUG_TYPE "asm-printer" 35 36 namespace { 37 class MSP430AsmPrinter : public AsmPrinter { 38 public: 39 MSP430AsmPrinter(TargetMachine &TM, std::unique_ptr<MCStreamer> Streamer) 40 : AsmPrinter(TM, std::move(Streamer), ID) {} 41 42 StringRef getPassName() const override { return "MSP430 Assembly Printer"; } 43 44 bool runOnMachineFunction(MachineFunction &MF) override; 45 46 void PrintSymbolOperand(const MachineOperand &MO, raw_ostream &O) override; 47 void printOperand(const MachineInstr *MI, int OpNum, raw_ostream &O, 48 bool PrefixHash = true); 49 void printSrcMemOperand(const MachineInstr *MI, int OpNum, 50 raw_ostream &O); 51 bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo, 52 const char *ExtraCode, raw_ostream &O) override; 53 bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo, 54 const char *ExtraCode, raw_ostream &O) override; 55 void emitInstruction(const MachineInstr *MI) override; 56 57 void EmitInterruptVectorSection(MachineFunction &ISR); 58 59 static char ID; 60 }; 61 } // end of anonymous namespace 62 63 void MSP430AsmPrinter::PrintSymbolOperand(const MachineOperand &MO, 64 raw_ostream &O) { 65 uint64_t Offset = MO.getOffset(); 66 if (Offset) 67 O << '(' << Offset << '+'; 68 69 getSymbol(MO.getGlobal())->print(O, MAI); 70 71 if (Offset) 72 O << ')'; 73 } 74 75 void MSP430AsmPrinter::printOperand(const MachineInstr *MI, int OpNum, 76 raw_ostream &O, bool PrefixHash) { 77 const MachineOperand &MO = MI->getOperand(OpNum); 78 switch (MO.getType()) { 79 default: llvm_unreachable("Not implemented yet!"); 80 case MachineOperand::MO_Register: 81 O << MSP430InstPrinter::getRegisterName(MO.getReg()); 82 return; 83 case MachineOperand::MO_Immediate: 84 if (PrefixHash) 85 O << '#'; 86 O << MO.getImm(); 87 return; 88 case MachineOperand::MO_MachineBasicBlock: 89 MO.getMBB()->getSymbol()->print(O, MAI); 90 return; 91 case MachineOperand::MO_GlobalAddress: { 92 // If the global address expression is a part of displacement field with a 93 // register base, we should not emit any prefix symbol here, e.g. 94 // mov.w glb(r1), r2 95 // Otherwise (!) msp430-as will silently miscompile the output :( 96 if (PrefixHash) 97 O << '#'; 98 PrintSymbolOperand(MO, O); 99 return; 100 } 101 } 102 } 103 104 void MSP430AsmPrinter::printSrcMemOperand(const MachineInstr *MI, int OpNum, 105 raw_ostream &O) { 106 const MachineOperand &Base = MI->getOperand(OpNum); 107 const MachineOperand &Disp = MI->getOperand(OpNum+1); 108 109 // Print displacement first 110 111 // Imm here is in fact global address - print extra modifier. 112 if (Disp.isImm() && Base.getReg() == MSP430::SR) 113 O << '&'; 114 printOperand(MI, OpNum + 1, O, /*PrefixHash=*/false); 115 116 // Print register base field 117 if (Base.getReg() != MSP430::SR && Base.getReg() != MSP430::PC) { 118 O << '('; 119 printOperand(MI, OpNum, O); 120 O << ')'; 121 } 122 } 123 124 /// PrintAsmOperand - Print out an operand for an inline asm expression. 125 /// 126 bool MSP430AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo, 127 const char *ExtraCode, raw_ostream &O) { 128 // Does this asm operand have a single letter operand modifier? 129 if (ExtraCode && ExtraCode[0]) 130 return AsmPrinter::PrintAsmOperand(MI, OpNo, ExtraCode, O); 131 132 printOperand(MI, OpNo, O); 133 return false; 134 } 135 136 bool MSP430AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, 137 unsigned OpNo, 138 const char *ExtraCode, 139 raw_ostream &O) { 140 if (ExtraCode && ExtraCode[0]) { 141 return true; // Unknown modifier. 142 } 143 printSrcMemOperand(MI, OpNo, O); 144 return false; 145 } 146 147 //===----------------------------------------------------------------------===// 148 void MSP430AsmPrinter::emitInstruction(const MachineInstr *MI) { 149 MSP430_MC::verifyInstructionPredicates(MI->getOpcode(), 150 getSubtargetInfo().getFeatureBits()); 151 152 MSP430MCInstLower MCInstLowering(OutContext, *this); 153 154 MCInst TmpInst; 155 MCInstLowering.Lower(MI, TmpInst); 156 EmitToStreamer(*OutStreamer, TmpInst); 157 } 158 159 void MSP430AsmPrinter::EmitInterruptVectorSection(MachineFunction &ISR) { 160 MCSection *Cur = OutStreamer->getCurrentSectionOnly(); 161 const auto *F = &ISR.getFunction(); 162 if (F->getCallingConv() != CallingConv::MSP430_INTR) { 163 report_fatal_error("Functions with 'interrupt' attribute must have msp430_intrcc CC"); 164 } 165 StringRef IVIdx = F->getFnAttribute("interrupt").getValueAsString(); 166 MCSection *IV = OutStreamer->getContext().getELFSection( 167 "__interrupt_vector_" + IVIdx, 168 ELF::SHT_PROGBITS, ELF::SHF_ALLOC | ELF::SHF_EXECINSTR); 169 OutStreamer->switchSection(IV); 170 171 const MCSymbol *FunctionSymbol = getSymbol(F); 172 OutStreamer->emitSymbolValue(FunctionSymbol, TM.getProgramPointerSize()); 173 OutStreamer->switchSection(Cur); 174 } 175 176 bool MSP430AsmPrinter::runOnMachineFunction(MachineFunction &MF) { 177 // Emit separate section for an interrupt vector if ISR 178 if (MF.getFunction().hasFnAttribute("interrupt")) { 179 EmitInterruptVectorSection(MF); 180 } 181 182 SetupMachineFunction(MF); 183 emitFunctionBody(); 184 return false; 185 } 186 187 char MSP430AsmPrinter::ID = 0; 188 189 INITIALIZE_PASS(MSP430AsmPrinter, "msp430-asm-printer", 190 "MSP430 Assembly Printer", false, false) 191 192 // Force static initialization. 193 extern "C" LLVM_ABI LLVM_EXTERNAL_VISIBILITY void 194 LLVMInitializeMSP430AsmPrinter() { 195 RegisterAsmPrinter<MSP430AsmPrinter> X(getTheMSP430Target()); 196 } 197