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 "MSP430.h" 16 #include "MSP430InstrInfo.h" 17 #include "MSP430MCInstLower.h" 18 #include "MSP430TargetMachine.h" 19 #include "TargetInfo/MSP430TargetInfo.h" 20 #include "llvm/BinaryFormat/ELF.h" 21 #include "llvm/CodeGen/AsmPrinter.h" 22 #include "llvm/CodeGen/MachineConstantPool.h" 23 #include "llvm/CodeGen/MachineFunctionPass.h" 24 #include "llvm/CodeGen/MachineInstr.h" 25 #include "llvm/CodeGen/MachineModuleInfo.h" 26 #include "llvm/IR/Constants.h" 27 #include "llvm/IR/DerivedTypes.h" 28 #include "llvm/IR/Mangler.h" 29 #include "llvm/IR/Module.h" 30 #include "llvm/MC/MCAsmInfo.h" 31 #include "llvm/MC/MCInst.h" 32 #include "llvm/MC/MCSectionELF.h" 33 #include "llvm/MC/MCStreamer.h" 34 #include "llvm/MC/MCSymbol.h" 35 #include "llvm/Support/TargetRegistry.h" 36 #include "llvm/Support/raw_ostream.h" 37 using namespace llvm; 38 39 #define DEBUG_TYPE "asm-printer" 40 41 namespace { 42 class MSP430AsmPrinter : public AsmPrinter { 43 public: 44 MSP430AsmPrinter(TargetMachine &TM, std::unique_ptr<MCStreamer> Streamer) 45 : AsmPrinter(TM, std::move(Streamer)) {} 46 47 StringRef getPassName() const override { return "MSP430 Assembly Printer"; } 48 49 bool runOnMachineFunction(MachineFunction &MF) override; 50 51 void PrintSymbolOperand(const MachineOperand &MO, raw_ostream &O) override; 52 void printOperand(const MachineInstr *MI, int OpNum, 53 raw_ostream &O, const char* Modifier = nullptr); 54 void printSrcMemOperand(const MachineInstr *MI, int OpNum, 55 raw_ostream &O); 56 bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo, 57 const char *ExtraCode, raw_ostream &O) override; 58 bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo, 59 const char *ExtraCode, raw_ostream &O) override; 60 void emitInstruction(const MachineInstr *MI) override; 61 62 void EmitInterruptVectorSection(MachineFunction &ISR); 63 }; 64 } // end of anonymous namespace 65 66 void MSP430AsmPrinter::PrintSymbolOperand(const MachineOperand &MO, 67 raw_ostream &O) { 68 uint64_t Offset = MO.getOffset(); 69 if (Offset) 70 O << '(' << Offset << '+'; 71 72 getSymbol(MO.getGlobal())->print(O, MAI); 73 74 if (Offset) 75 O << ')'; 76 } 77 78 void MSP430AsmPrinter::printOperand(const MachineInstr *MI, int OpNum, 79 raw_ostream &O, const char *Modifier) { 80 const MachineOperand &MO = MI->getOperand(OpNum); 81 switch (MO.getType()) { 82 default: llvm_unreachable("Not implemented yet!"); 83 case MachineOperand::MO_Register: 84 O << MSP430InstPrinter::getRegisterName(MO.getReg()); 85 return; 86 case MachineOperand::MO_Immediate: 87 if (!Modifier || strcmp(Modifier, "nohash")) 88 O << '#'; 89 O << MO.getImm(); 90 return; 91 case MachineOperand::MO_MachineBasicBlock: 92 MO.getMBB()->getSymbol()->print(O, MAI); 93 return; 94 case MachineOperand::MO_GlobalAddress: { 95 // If the global address expression is a part of displacement field with a 96 // register base, we should not emit any prefix symbol here, e.g. 97 // mov.w glb(r1), r2 98 // Otherwise (!) msp430-as will silently miscompile the output :( 99 if (!Modifier || strcmp(Modifier, "nohash")) 100 O << '#'; 101 PrintSymbolOperand(MO, O); 102 return; 103 } 104 } 105 } 106 107 void MSP430AsmPrinter::printSrcMemOperand(const MachineInstr *MI, int OpNum, 108 raw_ostream &O) { 109 const MachineOperand &Base = MI->getOperand(OpNum); 110 const MachineOperand &Disp = MI->getOperand(OpNum+1); 111 112 // Print displacement first 113 114 // Imm here is in fact global address - print extra modifier. 115 if (Disp.isImm() && Base.getReg() == MSP430::SR) 116 O << '&'; 117 printOperand(MI, OpNum+1, O, "nohash"); 118 119 // Print register base field 120 if (Base.getReg() != MSP430::SR && Base.getReg() != MSP430::PC) { 121 O << '('; 122 printOperand(MI, OpNum, O); 123 O << ')'; 124 } 125 } 126 127 /// PrintAsmOperand - Print out an operand for an inline asm expression. 128 /// 129 bool MSP430AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo, 130 const char *ExtraCode, raw_ostream &O) { 131 // Does this asm operand have a single letter operand modifier? 132 if (ExtraCode && ExtraCode[0]) 133 return AsmPrinter::PrintAsmOperand(MI, OpNo, ExtraCode, O); 134 135 printOperand(MI, OpNo, O); 136 return false; 137 } 138 139 bool MSP430AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, 140 unsigned OpNo, 141 const char *ExtraCode, 142 raw_ostream &O) { 143 if (ExtraCode && ExtraCode[0]) { 144 return true; // Unknown modifier. 145 } 146 printSrcMemOperand(MI, OpNo, O); 147 return false; 148 } 149 150 //===----------------------------------------------------------------------===// 151 void MSP430AsmPrinter::emitInstruction(const MachineInstr *MI) { 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 // Force static initialization. 188 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeMSP430AsmPrinter() { 189 RegisterAsmPrinter<MSP430AsmPrinter> X(getTheMSP430Target()); 190 } 191