llvm-project/llvm/utils/TableGen/TGLexer.h

134 lines
3.4 KiB
C++

//===- TGLexer.h - Lexer for TableGen Files ---------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This class represents the Lexer for tablegen files.
//
//===----------------------------------------------------------------------===//
#ifndef TGLEXER_H
#define TGLEXER_H
#include <vector>
#include <string>
#include <iosfwd>
#include <cassert>
namespace llvm {
class MemoryBuffer;
namespace tgtok {
enum TokKind {
// Markers
Eof, Error,
// Tokens with no info.
minus, plus, // - +
l_square, r_square, // [ ]
l_brace, r_brace, // { }
l_paren, r_paren, // ( )
less, greater, // < >
colon, semi, // ; :
comma, period, // , .
equal, question, // = ?
// Keywords.
Bit, Bits, Class, Code, Dag, Def, Defm, Field, In, Int, Let, List,
MultiClass, String,
// !keywords.
XConcat, XSRA, XSRL, XSHL, XStrConcat,
// Integer value.
IntVal,
// String valued tokens.
Id, StrVal, VarName, CodeFragment
};
}
/// TGLexer - TableGen Lexer class.
class TGLexer {
const char *CurPtr;
unsigned CurLineNo;
MemoryBuffer *CurBuf;
// Information about the current token.
const char *TokStart;
tgtok::TokKind CurCode;
std::string CurStrVal; // This is valid for ID, STRVAL, VARNAME, CODEFRAGMENT
int CurIntVal; // This is valid for INTVAL.
/// IncludeRec / IncludeStack - This captures the current set of include
/// directives we are nested within.
struct IncludeRec {
MemoryBuffer *Buffer;
const char *CurPtr;
unsigned LineNo;
IncludeRec(MemoryBuffer *buffer, const char *curPtr, unsigned lineNo)
: Buffer(buffer), CurPtr(curPtr), LineNo(lineNo) {}
};
std::vector<IncludeRec> IncludeStack;
// IncludeDirectories - This is the list of directories we should search for
// include files in.
std::vector<std::string> IncludeDirectories;
public:
TGLexer(MemoryBuffer *StartBuf);
~TGLexer();
void setIncludeDirs(const std::vector<std::string> &Dirs) {
IncludeDirectories = Dirs;
}
tgtok::TokKind Lex() {
return CurCode = LexToken();
}
tgtok::TokKind getCode() const { return CurCode; }
const std::string &getCurStrVal() const {
assert((CurCode == tgtok::Id || CurCode == tgtok::StrVal ||
CurCode == tgtok::VarName || CurCode == tgtok::CodeFragment) &&
"This token doesn't have a string value");
return CurStrVal;
}
int getCurIntVal() const {
assert(CurCode == tgtok::IntVal && "This token isn't an integer");
return CurIntVal;
}
typedef const char* LocTy;
LocTy getLoc() const { return TokStart; }
void PrintError(LocTy Loc, const std::string &Msg) const;
void PrintIncludeStack(std::ostream &OS) const;
private:
/// LexToken - Read the next token and return its code.
tgtok::TokKind LexToken();
tgtok::TokKind ReturnError(const char *Loc, const std::string &Msg);
int getNextChar();
void SkipBCPLComment();
bool SkipCComment();
tgtok::TokKind LexIdentifier();
bool LexInclude();
tgtok::TokKind LexString();
tgtok::TokKind LexVarName();
tgtok::TokKind LexNumber();
tgtok::TokKind LexBracket();
tgtok::TokKind LexExclaim();
};
} // end namespace llvm
#endif