lib/Target/MSP430/MSP430AsmPrinter.cpp

   1 //===-- MSP430AsmPrinter.cpp - MSP430 LLVM assembly writer ----------------===//
   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 // This file contains a printer that converts from our internal representation
  11 // of machine-dependent LLVM code to the MSP430 assembly language.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #define DEBUG_TYPE "asm-printer"
  16 #include "MSP430.h"
  17 #include "MSP430InstrInfo.h"
  18 #include "MSP430MCAsmInfo.h"
  19 #include "MSP430MCInstLower.h"
  20 #include "MSP430TargetMachine.h"
  21 #include "InstPrinter/MSP430InstPrinter.h"
  22 #include "llvm/Constants.h"
  23 #include "llvm/DerivedTypes.h"
  24 #include "llvm/Module.h"
  25 #include "llvm/Assembly/Writer.h"
  26 #include "llvm/CodeGen/AsmPrinter.h"
  27 #include "llvm/CodeGen/MachineModuleInfo.h"
  28 #include "llvm/CodeGen/MachineFunctionPass.h"
  29 #include "llvm/CodeGen/MachineConstantPool.h"
  30 #include "llvm/CodeGen/MachineInstr.h"
  31 #include "llvm/MC/MCInst.h"
  32 #include "llvm/MC/MCStreamer.h"
  33 #include "llvm/MC/MCSymbol.h"
  34 #include "llvm/Target/Mangler.h"
  35 #include "llvm/Target/TargetData.h"
  36 #include "llvm/Target/TargetLoweringObjectFile.h"
  37 #include "llvm/Target/TargetRegistry.h"
  38 #include "llvm/Support/raw_ostream.h"
  39 using namespace llvm;
  40
  41 namespace {
  42   class MSP430AsmPrinter : public AsmPrinter {
  43   public:
  44     MSP430AsmPrinter(TargetMachine &TM, MCStreamer &Streamer)
  45       : AsmPrinter(TM, Streamer) {}
  46
  47     virtual const char *getPassName() const {
  48       return "MSP430 Assembly Printer";
  49     }
  50
  51     void printOperand(const MachineInstr *MI, int OpNum,
  52                       raw_ostream &O, const char* Modifier = 0);
  53     void printSrcMemOperand(const MachineInstr *MI, int OpNum,
  54                             raw_ostream &O);
  55     bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
  56                          unsigned AsmVariant, const char *ExtraCode,
  57                          raw_ostream &O);
  58     bool PrintAsmMemoryOperand(const MachineInstr *MI,
  59                                unsigned OpNo, unsigned AsmVariant,
  60                                const char *ExtraCode, raw_ostream &O);
  61     void EmitInstruction(const MachineInstr *MI);
  62   };
  63 } // end of anonymous namespace
  64
  65
  66 void MSP430AsmPrinter::printOperand(const MachineInstr *MI, int OpNum,
  67                                     raw_ostream &O, const char *Modifier) {
  68   const MachineOperand &MO = MI->getOperand(OpNum);
  69   switch (MO.getType()) {
  70   default: assert(0 && "Not implemented yet!");
  71   case MachineOperand::MO_Register:
  72     O << MSP430InstPrinter::getRegisterName(MO.getReg());
  73     return;
  74   case MachineOperand::MO_Immediate:
  75     if (!Modifier || strcmp(Modifier, "nohash"))
  76       O << '#';
  77     O << MO.getImm();
  78     return;
  79   case MachineOperand::MO_MachineBasicBlock:
  80     O << *MO.getMBB()->getSymbol();
  81     return;
  82   case MachineOperand::MO_GlobalAddress: {
  83     bool isMemOp  = Modifier && !strcmp(Modifier, "mem");
  84     uint64_t Offset = MO.getOffset();
  85
  86     // If the global address expression is a part of displacement field with a
  87     // register base, we should not emit any prefix symbol here, e.g.
  88     //   mov.w &foo, r1
  89     // vs
  90     //   mov.w glb(r1), r2
  91     // Otherwise (!) msp430-as will silently miscompile the output :(
  92     if (!Modifier || strcmp(Modifier, "nohash"))
  93       O << (isMemOp ? '&' : '#');
  94     if (Offset)
  95       O << '(' << Offset << '+';
  96
  97     O << *Mang->getSymbol(MO.getGlobal());
  98
  99     if (Offset)
 100       O << ')';
 101
 102     return;
 103   }
 104   case MachineOperand::MO_ExternalSymbol: {
 105     bool isMemOp  = Modifier && !strcmp(Modifier, "mem");
 106     O << (isMemOp ? '&' : '#');
 107     O << MAI->getGlobalPrefix() << MO.getSymbolName();
 108     return;
 109   }
 110   }
 111 }
 112
 113 void MSP430AsmPrinter::printSrcMemOperand(const MachineInstr *MI, int OpNum,
 114                                           raw_ostream &O) {
 115   const MachineOperand &Base = MI->getOperand(OpNum);
 116   const MachineOperand &Disp = MI->getOperand(OpNum+1);
 117
 118   // Print displacement first
 119
 120   // Imm here is in fact global address - print extra modifier.
 121   if (Disp.isImm() && !Base.getReg())
 122     O << '&';
 123   printOperand(MI, OpNum+1, O, "nohash");
 124
 125   // Print register base field
 126   if (Base.getReg()) {
 127     O << '(';
 128     printOperand(MI, OpNum, O);
 129     O << ')';
 130   }
 131 }
 132
 133 /// PrintAsmOperand - Print out an operand for an inline asm expression.
 134 ///
 135 bool MSP430AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
 136                                        unsigned AsmVariant,
 137                                        const char *ExtraCode, raw_ostream &O) {
 138   // Does this asm operand have a single letter operand modifier?
 139   if (ExtraCode && ExtraCode[0])
 140     return true; // Unknown modifier.
 141
 142   printOperand(MI, OpNo, O);
 143   return false;
 144 }
 145
 146 bool MSP430AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
 147                                              unsigned OpNo, unsigned AsmVariant,
 148                                              const char *ExtraCode,
 149                                              raw_ostream &O) {
 150   if (ExtraCode && ExtraCode[0]) {
 151     return true; // Unknown modifier.
 152   }
 153   printSrcMemOperand(MI, OpNo, O);
 154   return false;
 155 }
 156
 157 //===----------------------------------------------------------------------===//
 158 void MSP430AsmPrinter::EmitInstruction(const MachineInstr *MI) {
 159   MSP430MCInstLower MCInstLowering(OutContext, *Mang, *this);
 160
 161   MCInst TmpInst;
 162   MCInstLowering.Lower(MI, TmpInst);
 163   OutStreamer.EmitInstruction(TmpInst);
 164 }
 165
 166 static MCInstPrinter *createMSP430MCInstPrinter(const Target &T,
 167                                                 unsigned SyntaxVariant,
 168                                                 const MCAsmInfo &MAI) {
 169   if (SyntaxVariant == 0)
 170     return new MSP430InstPrinter(MAI);
 171   return 0;
 172 }
 173
 174 // Force static initialization.
 175 extern "C" void LLVMInitializeMSP430AsmPrinter() {
 176   RegisterAsmPrinter<MSP430AsmPrinter> X(TheMSP430Target);
 177   TargetRegistry::RegisterMCInstPrinter(TheMSP430Target,
 178                                         createMSP430MCInstPrinter);
 179 }