lib/Target/ARM/AsmParser/ARMAsmLexer.cpp

   1 //===-- ARMAsmLexer.cpp - Tokenize ARM assembly to AsmTokens --------------===//
   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 "ARM.h"
  11 #include "ARMTargetMachine.h"
  12
  13 #include "llvm/MC/MCAsmInfo.h"
  14 #include "llvm/MC/MCParser/MCAsmLexer.h"
  15 #include "llvm/MC/MCParser/MCParsedAsmOperand.h"
  16
  17 #include "llvm/Target/TargetAsmLexer.h"
  18 #include "llvm/Target/TargetMachine.h"
  19 #include "llvm/Target/TargetRegistry.h"
  20
  21 #include "llvm/ADT/OwningPtr.h"
  22 #include "llvm/ADT/SmallVector.h"
  23 #include "llvm/ADT/StringExtras.h"
  24 #include "llvm/ADT/StringSwitch.h"
  25
  26 #include <string>
  27 #include <map>
  28
  29 using namespace llvm;
  30
  31 namespace {
  32
  33 class ARMBaseAsmLexer : public TargetAsmLexer {
  34   const MCAsmInfo &AsmInfo;
  35
  36   const AsmToken &lexDefinite() {
  37     return getLexer()->Lex();
  38   }
  39
  40   AsmToken LexTokenUAL();
  41 protected:
  42   typedef std::map <std::string, unsigned> rmap_ty;
  43
  44   rmap_ty RegisterMap;
  45
  46   void InitRegisterMap(const TargetRegisterInfo *info) {
  47     unsigned numRegs = info->getNumRegs();
  48
  49     for (unsigned i = 0; i < numRegs; ++i) {
  50       const char *regName = info->getName(i);
  51       if (regName)
  52         RegisterMap[regName] = i;
  53     }
  54   }
  55
  56   unsigned MatchRegisterName(StringRef Name) {
  57     rmap_ty::iterator iter = RegisterMap.find(Name.str());
  58     if (iter != RegisterMap.end())
  59       return iter->second;
  60     else
  61       return 0;
  62   }
  63
  64   AsmToken LexToken() {
  65     if (!Lexer) {
  66       SetError(SMLoc(), "No MCAsmLexer installed");
  67       return AsmToken(AsmToken::Error, "", 0);
  68     }
  69
  70     switch (AsmInfo.getAssemblerDialect()) {
  71     default:
  72       SetError(SMLoc(), "Unhandled dialect");
  73       return AsmToken(AsmToken::Error, "", 0);
  74     case 0:
  75       return LexTokenUAL();
  76     }
  77   }
  78 public:
  79   ARMBaseAsmLexer(const Target &T, const MCAsmInfo &MAI)
  80     : TargetAsmLexer(T), AsmInfo(MAI) {
  81   }
  82 };
  83
  84 class ARMAsmLexer : public ARMBaseAsmLexer {
  85 public:
  86   ARMAsmLexer(const Target &T, const MCAsmInfo &MAI)
  87     : ARMBaseAsmLexer(T, MAI) {
  88     std::string tripleString("arm-unknown-unknown");
  89     std::string featureString;
  90     std::string CPU;
  91     OwningPtr<const TargetMachine>
  92       targetMachine(T.createTargetMachine(tripleString, CPU, featureString));
  93     InitRegisterMap(targetMachine->getRegisterInfo());
  94   }
  95 };
  96
  97 class ThumbAsmLexer : public ARMBaseAsmLexer {
  98 public:
  99   ThumbAsmLexer(const Target &T, const MCAsmInfo &MAI)
 100     : ARMBaseAsmLexer(T, MAI) {
 101     std::string tripleString("thumb-unknown-unknown");
 102     std::string featureString;
 103     std::string CPU;
 104     OwningPtr<const TargetMachine>
 105       targetMachine(T.createTargetMachine(tripleString, CPU, featureString));
 106     InitRegisterMap(targetMachine->getRegisterInfo());
 107   }
 108 };
 109
 110 } // end anonymous namespace
 111
 112 AsmToken ARMBaseAsmLexer::LexTokenUAL() {
 113   const AsmToken &lexedToken = lexDefinite();
 114
 115   switch (lexedToken.getKind()) {
 116   default: break;
 117   case AsmToken::Error:
 118     SetError(Lexer->getErrLoc(), Lexer->getErr());
 119     break;
 120   case AsmToken::Identifier: {
 121     std::string upperCase = lexedToken.getString().str();
 122     std::string lowerCase = LowercaseString(upperCase);
 123     StringRef lowerRef(lowerCase);
 124
 125     unsigned regID = MatchRegisterName(lowerRef);
 126     // Check for register aliases.
 127     //   r13 -> sp
 128     //   r14 -> lr
 129     //   r15 -> pc
 130     //   ip  -> r12
 131     //   FIXME: Some assemblers support lots of others. Do we want them all?
 132     if (!regID) {
 133       regID = StringSwitch<unsigned>(lowerCase)
 134         .Case("r13", ARM::SP)
 135         .Case("r14", ARM::LR)
 136         .Case("r15", ARM::PC)
 137         .Case("ip", ARM::R12)
 138         .Default(0);
 139     }
 140
 141     if (regID)
 142       return AsmToken(AsmToken::Register,
 143                       lexedToken.getString(),
 144                       static_cast<int64_t>(regID));
 145   }
 146   }
 147
 148   return AsmToken(lexedToken);
 149 }
 150
 151 extern "C" void LLVMInitializeARMAsmLexer() {
 152   RegisterAsmLexer<ARMAsmLexer> X(TheARMTarget);
 153   RegisterAsmLexer<ThumbAsmLexer> Y(TheThumbTarget);
 154 }