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diff --git a/lib/MC/MCParser/AsmLexer.cpp b/lib/MC/MCParser/AsmLexer.cpp
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+//===- AsmLexer.cpp - Lexer for Assembly Files ----------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This class implements the lexer for assembly files.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/MC/MCParser/AsmLexer.h"
+#include "llvm/Support/SMLoc.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include <cerrno>
+#include <cstdio>
+#include <cstdlib>
+using namespace llvm;
+
+AsmLexer::AsmLexer(const MCAsmInfo &_MAI) : MAI(_MAI) {
+ CurBuf = NULL;
+ CurPtr = NULL;
+ TokStart = 0;
+}
+
+AsmLexer::~AsmLexer() {
+}
+
+void AsmLexer::setBuffer(const MemoryBuffer *buf, const char *ptr) {
+ CurBuf = buf;
+
+ if (ptr)
+ CurPtr = ptr;
+ else
+ CurPtr = CurBuf->getBufferStart();
+
+ TokStart = 0;
+}
+
+SMLoc AsmLexer::getLoc() const {
+ return SMLoc::getFromPointer(TokStart);
+}
+
+/// ReturnError - Set the error to the specified string at the specified
+/// location. This is defined to always return AsmToken::Error.
+AsmToken AsmLexer::ReturnError(const char *Loc, const std::string &Msg) {
+ SetError(SMLoc::getFromPointer(Loc), Msg);
+
+ return AsmToken(AsmToken::Error, StringRef(Loc, 0));
+}
+
+int AsmLexer::getNextChar() {
+ char CurChar = *CurPtr++;
+ switch (CurChar) {
+ default:
+ return (unsigned char)CurChar;
+ case 0:
+ // A nul character in the stream is either the end of the current buffer or
+ // a random nul in the file. Disambiguate that here.
+ if (CurPtr-1 != CurBuf->getBufferEnd())
+ return 0; // Just whitespace.
+
+ // Otherwise, return end of file.
+ --CurPtr; // Another call to lex will return EOF again.
+ return EOF;
+ }
+}
+
+/// LexIdentifier: [a-zA-Z_.][a-zA-Z0-9_$.@]*
+AsmToken AsmLexer::LexIdentifier() {
+ while (isalnum(*CurPtr) || *CurPtr == '_' || *CurPtr == '$' ||
+ *CurPtr == '.' || *CurPtr == '@')
+ ++CurPtr;
+ return AsmToken(AsmToken::Identifier, StringRef(TokStart, CurPtr - TokStart));
+}
+
+/// LexSlash: Slash: /
+/// C-Style Comment: /* ... */
+AsmToken AsmLexer::LexSlash() {
+ switch (*CurPtr) {
+ case '*': break; // C style comment.
+ case '/': return ++CurPtr, LexLineComment();
+ default: return AsmToken(AsmToken::Slash, StringRef(CurPtr, 1));
+ }
+
+ // C Style comment.
+ ++CurPtr; // skip the star.
+ while (1) {
+ int CurChar = getNextChar();
+ switch (CurChar) {
+ case EOF:
+ return ReturnError(TokStart, "unterminated comment");
+ case '*':
+ // End of the comment?
+ if (CurPtr[0] != '/') break;
+
+ ++CurPtr; // End the */.
+ return LexToken();
+ }
+ }
+}
+
+/// LexLineComment: Comment: #[^\n]*
+/// : //[^\n]*
+AsmToken AsmLexer::LexLineComment() {
+ // FIXME: This is broken if we happen to a comment at the end of a file, which
+ // was .included, and which doesn't end with a newline.
+ int CurChar = getNextChar();
+ while (CurChar != '\n' && CurChar != '\n' && CurChar != EOF)
+ CurChar = getNextChar();
+
+ if (CurChar == EOF)
+ return AsmToken(AsmToken::Eof, StringRef(CurPtr, 0));
+ return AsmToken(AsmToken::EndOfStatement, StringRef(CurPtr, 0));
+}
+
+
+/// LexDigit: First character is [0-9].
+/// Local Label: [0-9][:]
+/// Forward/Backward Label: [0-9][fb]
+/// Binary integer: 0b[01]+
+/// Octal integer: 0[0-7]+
+/// Hex integer: 0x[0-9a-fA-F]+
+/// Decimal integer: [1-9][0-9]*
+/// TODO: FP literal.
+AsmToken AsmLexer::LexDigit() {
+ if (*CurPtr == ':')
+ return ReturnError(TokStart, "FIXME: local label not implemented");
+ if (*CurPtr == 'f' || *CurPtr == 'b')
+ return ReturnError(TokStart, "FIXME: directional label not implemented");
+
+ // Decimal integer: [1-9][0-9]*
+ if (CurPtr[-1] != '0') {
+ while (isdigit(*CurPtr))
+ ++CurPtr;
+
+ StringRef Result(TokStart, CurPtr - TokStart);
+
+ long long Value;
+ if (Result.getAsInteger(10, Value))
+ return ReturnError(TokStart, "Invalid decimal number");
+ return AsmToken(AsmToken::Integer, Result, Value);
+ }
+
+ if (*CurPtr == 'b') {
+ ++CurPtr;
+ const char *NumStart = CurPtr;
+ while (CurPtr[0] == '0' || CurPtr[0] == '1')
+ ++CurPtr;
+
+ // Requires at least one binary digit.
+ if (CurPtr == NumStart)
+ return ReturnError(TokStart, "Invalid binary number");
+
+ StringRef Result(TokStart, CurPtr - TokStart);
+
+ long long Value;
+ if (Result.getAsInteger(2, Value))
+ return ReturnError(TokStart, "Invalid binary number");
+
+ return AsmToken(AsmToken::Integer, Result, Value);
+ }
+
+ if (*CurPtr == 'x') {
+ ++CurPtr;
+ const char *NumStart = CurPtr;
+ while (isxdigit(CurPtr[0]))
+ ++CurPtr;
+
+ // Requires at least one hex digit.
+ if (CurPtr == NumStart)
+ return ReturnError(CurPtr-2, "Invalid hexadecimal number");
+
+ unsigned long long Result;
+ if (StringRef(TokStart, CurPtr - TokStart).getAsInteger(0, Result))
+ return ReturnError(TokStart, "Invalid hexadecimal number");
+
+ return AsmToken(AsmToken::Integer, StringRef(TokStart, CurPtr - TokStart),
+ (int64_t)Result);
+ }
+
+ // Must be an octal number, it starts with 0.
+ while (*CurPtr >= '0' && *CurPtr <= '7')
+ ++CurPtr;
+
+ StringRef Result(TokStart, CurPtr - TokStart);
+ long long Value;
+ if (Result.getAsInteger(8, Value))
+ return ReturnError(TokStart, "Invalid octal number");
+
+ return AsmToken(AsmToken::Integer, Result, Value);
+}
+
+/// LexQuote: String: "..."
+AsmToken AsmLexer::LexQuote() {
+ int CurChar = getNextChar();
+ // TODO: does gas allow multiline string constants?
+ while (CurChar != '"') {
+ if (CurChar == '\\') {
+ // Allow \", etc.
+ CurChar = getNextChar();
+ }
+
+ if (CurChar == EOF)
+ return ReturnError(TokStart, "unterminated string constant");
+
+ CurChar = getNextChar();
+ }
+
+ return AsmToken(AsmToken::String, StringRef(TokStart, CurPtr - TokStart));
+}
+
+StringRef AsmLexer::LexUntilEndOfStatement() {
+ TokStart = CurPtr;
+
+ while (!isAtStartOfComment(*CurPtr) && // Start of line comment.
+ *CurPtr != ';' && // End of statement marker.
+ *CurPtr != '\n' &&
+ *CurPtr != '\r' &&
+ (*CurPtr != 0 || CurPtr != CurBuf->getBufferEnd())) {
+ ++CurPtr;
+ }
+ return StringRef(TokStart, CurPtr-TokStart);
+}
+
+bool AsmLexer::isAtStartOfComment(char Char) {
+ // FIXME: This won't work for multi-character comment indicators like "//".
+ return Char == *MAI.getCommentString();
+}
+
+AsmToken AsmLexer::LexToken() {
+ TokStart = CurPtr;
+ // This always consumes at least one character.
+ int CurChar = getNextChar();
+
+ if (isAtStartOfComment(CurChar))
+ return LexLineComment();
+
+ switch (CurChar) {
+ default:
+ // Handle identifier: [a-zA-Z_.][a-zA-Z0-9_$.@]*
+ if (isalpha(CurChar) || CurChar == '_' || CurChar == '.')
+ return LexIdentifier();
+
+ // Unknown character, emit an error.
+ return ReturnError(TokStart, "invalid character in input");
+ case EOF: return AsmToken(AsmToken::Eof, StringRef(TokStart, 0));
+ case 0:
+ case ' ':
+ case '\t':
+ // Ignore whitespace.
+ return LexToken();
+ case '\n': // FALL THROUGH.
+ case '\r': // FALL THROUGH.
+ case ';': return AsmToken(AsmToken::EndOfStatement, StringRef(TokStart, 1));
+ case ':': return AsmToken(AsmToken::Colon, StringRef(TokStart, 1));
+ case '+': return AsmToken(AsmToken::Plus, StringRef(TokStart, 1));
+ case '-': return AsmToken(AsmToken::Minus, StringRef(TokStart, 1));
+ case '~': return AsmToken(AsmToken::Tilde, StringRef(TokStart, 1));
+ case '(': return AsmToken(AsmToken::LParen, StringRef(TokStart, 1));
+ case ')': return AsmToken(AsmToken::RParen, StringRef(TokStart, 1));
+ case '[': return AsmToken(AsmToken::LBrac, StringRef(TokStart, 1));
+ case ']': return AsmToken(AsmToken::RBrac, StringRef(TokStart, 1));
+ case '{': return AsmToken(AsmToken::LCurly, StringRef(TokStart, 1));
+ case '}': return AsmToken(AsmToken::RCurly, StringRef(TokStart, 1));
+ case '*': return AsmToken(AsmToken::Star, StringRef(TokStart, 1));
+ case ',': return AsmToken(AsmToken::Comma, StringRef(TokStart, 1));
+ case '$': return AsmToken(AsmToken::Dollar, StringRef(TokStart, 1));
+ case '=':
+ if (*CurPtr == '=')
+ return ++CurPtr, AsmToken(AsmToken::EqualEqual, StringRef(TokStart, 2));
+ return AsmToken(AsmToken::Equal, StringRef(TokStart, 1));
+ case '|':
+ if (*CurPtr == '|')
+ return ++CurPtr, AsmToken(AsmToken::PipePipe, StringRef(TokStart, 2));
+ return AsmToken(AsmToken::Pipe, StringRef(TokStart, 1));
+ case '^': return AsmToken(AsmToken::Caret, StringRef(TokStart, 1));
+ case '&':
+ if (*CurPtr == '&')
+ return ++CurPtr, AsmToken(AsmToken::AmpAmp, StringRef(TokStart, 2));
+ return AsmToken(AsmToken::Amp, StringRef(TokStart, 1));
+ case '!':
+ if (*CurPtr == '=')
+ return ++CurPtr, AsmToken(AsmToken::ExclaimEqual, StringRef(TokStart, 2));
+ return AsmToken(AsmToken::Exclaim, StringRef(TokStart, 1));
+ case '%': return AsmToken(AsmToken::Percent, StringRef(TokStart, 1));
+ case '/': return LexSlash();
+ case '#': return AsmToken(AsmToken::Hash, StringRef(TokStart, 1));
+ case '"': return LexQuote();
+ case '0': case '1': case '2': case '3': case '4':
+ case '5': case '6': case '7': case '8': case '9':
+ return LexDigit();
+ case '<':
+ switch (*CurPtr) {
+ case '<': return ++CurPtr, AsmToken(AsmToken::LessLess,
+ StringRef(TokStart, 2));
+ case '=': return ++CurPtr, AsmToken(AsmToken::LessEqual,
+ StringRef(TokStart, 2));
+ case '>': return ++CurPtr, AsmToken(AsmToken::LessGreater,
+ StringRef(TokStart, 2));
+ default: return AsmToken(AsmToken::Less, StringRef(TokStart, 1));
+ }
+ case '>':
+ switch (*CurPtr) {
+ case '>': return ++CurPtr, AsmToken(AsmToken::GreaterGreater,
+ StringRef(TokStart, 2));
+ case '=': return ++CurPtr, AsmToken(AsmToken::GreaterEqual,
+ StringRef(TokStart, 2));
+ default: return AsmToken(AsmToken::Greater, StringRef(TokStart, 1));
+ }
+
+ // TODO: Quoted identifiers (objc methods etc)
+ // local labels: [0-9][:]
+ // Forward/backward labels: [0-9][fb]
+ // Integers, fp constants, character constants.
+ }
+}
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