1 files changed, 755 insertions, 0 deletions

diff --git a/contrib/llvm-project/llvm/lib/MC/MCParser/AsmLexer.cpp b/contrib/llvm-project/llvm/lib/MC/MCParser/AsmLexer.cpp
new file mode 100644
index 000000000000..9155ae05d29d
--- /dev/null
+++ b/contrib/llvm-project/llvm/lib/MC/MCParser/AsmLexer.cpp
@@ -0,0 +1,755 @@
+//===- AsmLexer.cpp - Lexer for Assembly Files ----------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This class implements the lexer for assembly files.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/MC/MCParser/AsmLexer.h"
+#include "llvm/ADT/APInt.h"
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/StringSwitch.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCParser/MCAsmLexer.h"
+#include "llvm/Support/SMLoc.h"
+#include "llvm/Support/SaveAndRestore.h"
+#include <cassert>
+#include <cctype>
+#include <cstdio>
+#include <cstring>
+#include <string>
+#include <tuple>
+#include <utility>
+
+using namespace llvm;
+
+AsmLexer::AsmLexer(const MCAsmInfo &MAI) : MAI(MAI) {
+  AllowAtInIdentifier = !StringRef(MAI.getCommentString()).startswith("@");
+}
+
+AsmLexer::~AsmLexer() = default;
+
+void AsmLexer::setBuffer(StringRef Buf, const char *ptr) {
+  CurBuf = Buf;
+
+  if (ptr)
+    CurPtr = ptr;
+  else
+    CurPtr = CurBuf.begin();
+
+  TokStart = nullptr;
+}
+
+/// 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, CurPtr - Loc));
+}
+
+int AsmLexer::getNextChar() {
+  if (CurPtr == CurBuf.end())
+    return EOF;
+  return (unsigned char)*CurPtr++;
+}
+
+/// The leading integral digit sequence and dot should have already been
+/// consumed, some or all of the fractional digit sequence *can* have been
+/// consumed.
+AsmToken AsmLexer::LexFloatLiteral() {
+  // Skip the fractional digit sequence.
+  while (isDigit(*CurPtr))
+    ++CurPtr;
+
+  if (*CurPtr == '-' || *CurPtr == '+')
+    return ReturnError(CurPtr, "Invalid sign in float literal");
+
+  // Check for exponent
+  if ((*CurPtr == 'e' || *CurPtr == 'E')) {
+    ++CurPtr;
+
+    if (*CurPtr == '-' || *CurPtr == '+')
+      ++CurPtr;
+
+    while (isDigit(*CurPtr))
+      ++CurPtr;
+  }
+
+  return AsmToken(AsmToken::Real,
+                  StringRef(TokStart, CurPtr - TokStart));
+}
+
+/// LexHexFloatLiteral matches essentially (.[0-9a-fA-F]*)?[pP][+-]?[0-9a-fA-F]+
+/// while making sure there are enough actual digits around for the constant to
+/// be valid.
+///
+/// The leading "0x[0-9a-fA-F]*" (i.e. integer part) has already been consumed
+/// before we get here.
+AsmToken AsmLexer::LexHexFloatLiteral(bool NoIntDigits) {
+  assert((*CurPtr == 'p' || *CurPtr == 'P' || *CurPtr == '.') &&
+         "unexpected parse state in floating hex");
+  bool NoFracDigits = true;
+
+  // Skip the fractional part if there is one
+  if (*CurPtr == '.') {
+    ++CurPtr;
+
+    const char *FracStart = CurPtr;
+    while (isHexDigit(*CurPtr))
+      ++CurPtr;
+
+    NoFracDigits = CurPtr == FracStart;
+  }
+
+  if (NoIntDigits && NoFracDigits)
+    return ReturnError(TokStart, "invalid hexadecimal floating-point constant: "
+                                 "expected at least one significand digit");
+
+  // Make sure we do have some kind of proper exponent part
+  if (*CurPtr != 'p' && *CurPtr != 'P')
+    return ReturnError(TokStart, "invalid hexadecimal floating-point constant: "
+                                 "expected exponent part 'p'");
+  ++CurPtr;
+
+  if (*CurPtr == '+' || *CurPtr == '-')
+    ++CurPtr;
+
+  // N.b. exponent digits are *not* hex
+  const char *ExpStart = CurPtr;
+  while (isDigit(*CurPtr))
+    ++CurPtr;
+
+  if (CurPtr == ExpStart)
+    return ReturnError(TokStart, "invalid hexadecimal floating-point constant: "
+                                 "expected at least one exponent digit");
+
+  return AsmToken(AsmToken::Real, StringRef(TokStart, CurPtr - TokStart));
+}
+
+/// LexIdentifier: [a-zA-Z_.][a-zA-Z0-9_$.@?]*
+static bool IsIdentifierChar(char c, bool AllowAt) {
+  return isAlnum(c) || c == '_' || c == '$' || c == '.' ||
+         (c == '@' && AllowAt) || c == '?';
+}
+
+AsmToken AsmLexer::LexIdentifier() {
+  // Check for floating point literals.
+  if (CurPtr[-1] == '.' && isDigit(*CurPtr)) {
+    // Disambiguate a .1243foo identifier from a floating literal.
+    while (isDigit(*CurPtr))
+      ++CurPtr;
+
+    if (!IsIdentifierChar(*CurPtr, AllowAtInIdentifier) ||
+        *CurPtr == 'e' || *CurPtr == 'E')
+      return LexFloatLiteral();
+  }
+
+  while (IsIdentifierChar(*CurPtr, AllowAtInIdentifier))
+    ++CurPtr;
+
+  // Handle . as a special case.
+  if (CurPtr == TokStart+1 && TokStart[0] == '.')
+    return AsmToken(AsmToken::Dot, StringRef(TokStart, 1));
+
+  return AsmToken(AsmToken::Identifier, StringRef(TokStart, CurPtr - TokStart));
+}
+
+/// LexSlash: Slash: /
+///           C-Style Comment: /* ... */
+AsmToken AsmLexer::LexSlash() {
+  switch (*CurPtr) {
+  case '*':
+    IsAtStartOfStatement = false;
+    break; // C style comment.
+  case '/':
+    ++CurPtr;
+    return LexLineComment();
+  default:
+    IsAtStartOfStatement = false;
+    return AsmToken(AsmToken::Slash, StringRef(TokStart, 1));
+  }
+
+  // C Style comment.
+  ++CurPtr;  // skip the star.
+  const char *CommentTextStart = CurPtr;
+  while (CurPtr != CurBuf.end()) {
+    switch (*CurPtr++) {
+    case '*':
+      // End of the comment?
+      if (*CurPtr != '/')
+        break;
+      // If we have a CommentConsumer, notify it about the comment.
+      if (CommentConsumer) {
+        CommentConsumer->HandleComment(
+            SMLoc::getFromPointer(CommentTextStart),
+            StringRef(CommentTextStart, CurPtr - 1 - CommentTextStart));
+      }
+      ++CurPtr;   // End the */.
+      return AsmToken(AsmToken::Comment,
+                      StringRef(TokStart, CurPtr - TokStart));
+    }
+  }
+  return ReturnError(TokStart, "unterminated comment");
+}
+
+/// LexLineComment: Comment: #[^\n]*
+///                        : //[^\n]*
+AsmToken AsmLexer::LexLineComment() {
+  // Mark This as an end of statement with a body of the
+  // comment. While it would be nicer to leave this two tokens,
+  // backwards compatability with TargetParsers makes keeping this in this form
+  // better.
+  const char *CommentTextStart = CurPtr;
+  int CurChar = getNextChar();
+  while (CurChar != '\n' && CurChar != '\r' && CurChar != EOF)
+    CurChar = getNextChar();
+  if (CurChar == '\r' && CurPtr != CurBuf.end() && *CurPtr == '\n')
+    ++CurPtr;
+
+  // If we have a CommentConsumer, notify it about the comment.
+  if (CommentConsumer) {
+    CommentConsumer->HandleComment(
+        SMLoc::getFromPointer(CommentTextStart),
+        StringRef(CommentTextStart, CurPtr - 1 - CommentTextStart));
+  }
+
+  IsAtStartOfLine = true;
+  // This is a whole line comment. leave newline
+  if (IsAtStartOfStatement)
+    return AsmToken(AsmToken::EndOfStatement,
+                    StringRef(TokStart, CurPtr - TokStart));
+  IsAtStartOfStatement = true;
+
+  return AsmToken(AsmToken::EndOfStatement,
+                  StringRef(TokStart, CurPtr - 1 - TokStart));
+}
+
+static void SkipIgnoredIntegerSuffix(const char *&CurPtr) {
+  // Skip ULL, UL, U, L and LL suffices.
+  if (CurPtr[0] == 'U')
+    ++CurPtr;
+  if (CurPtr[0] == 'L')
+    ++CurPtr;
+  if (CurPtr[0] == 'L')
+    ++CurPtr;
+}
+
+// Look ahead to search for first non-hex digit, if it's [hH], then we treat the
+// integer as a hexadecimal, possibly with leading zeroes.
+static unsigned doHexLookAhead(const char *&CurPtr, unsigned DefaultRadix,
+                               bool LexHex) {
+  const char *FirstNonDec = nullptr;
+  const char *LookAhead = CurPtr;
+  while (true) {
+    if (isDigit(*LookAhead)) {
+      ++LookAhead;
+    } else {
+      if (!FirstNonDec)
+        FirstNonDec = LookAhead;
+
+      // Keep going if we are looking for a 'h' suffix.
+      if (LexHex && isHexDigit(*LookAhead))
+        ++LookAhead;
+      else
+        break;
+    }
+  }
+  bool isHex = LexHex && (*LookAhead == 'h' || *LookAhead == 'H');
+  CurPtr = isHex || !FirstNonDec ? LookAhead : FirstNonDec;
+  if (isHex)
+    return 16;
+  return DefaultRadix;
+}
+
+static AsmToken intToken(StringRef Ref, APInt &Value)
+{
+  if (Value.isIntN(64))
+    return AsmToken(AsmToken::Integer, Ref, Value);
+  return AsmToken(AsmToken::BigNum, Ref, Value);
+}
+
+/// 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]+ or [0x]?[0-9][0-9a-fA-F]*[hH]
+///   Decimal integer: [1-9][0-9]*
+AsmToken AsmLexer::LexDigit() {
+  // MASM-flavor binary integer: [01]+[bB]
+  // MASM-flavor hexadecimal integer: [0-9][0-9a-fA-F]*[hH]
+  if (LexMasmIntegers && isdigit(CurPtr[-1])) {
+    const char *FirstNonBinary = (CurPtr[-1] != '0' && CurPtr[-1] != '1') ?
+                                   CurPtr - 1 : nullptr;
+    const char *OldCurPtr = CurPtr;
+    while (isHexDigit(*CurPtr)) {
+      if (*CurPtr != '0' && *CurPtr != '1' && !FirstNonBinary)
+        FirstNonBinary = CurPtr;
+      ++CurPtr;
+    }
+
+    unsigned Radix = 0;
+    if (*CurPtr == 'h' || *CurPtr == 'H') {
+      // hexadecimal number
+      ++CurPtr;
+      Radix = 16;
+    } else if (FirstNonBinary && FirstNonBinary + 1 == CurPtr &&
+               (*FirstNonBinary == 'b' || *FirstNonBinary == 'B'))
+      Radix = 2;
+
+    if (Radix == 2 || Radix == 16) {
+      StringRef Result(TokStart, CurPtr - TokStart);
+      APInt Value(128, 0, true);
+
+      if (Result.drop_back().getAsInteger(Radix, Value))
+        return ReturnError(TokStart, Radix == 2 ? "invalid binary number" :
+                             "invalid hexdecimal number");
+
+      // MSVC accepts and ignores type suffices on integer literals.
+      SkipIgnoredIntegerSuffix(CurPtr);
+
+      return intToken(Result, Value);
+   }
+
+    // octal/decimal integers, or floating point numbers, fall through
+    CurPtr = OldCurPtr;
+  }
+
+  // Decimal integer: [1-9][0-9]*
+  if (CurPtr[-1] != '0' || CurPtr[0] == '.') {
+    unsigned Radix = doHexLookAhead(CurPtr, 10, LexMasmIntegers);
+    bool isHex = Radix == 16;
+    // Check for floating point literals.
+    if (!isHex && (*CurPtr == '.' || *CurPtr == 'e' || *CurPtr == 'E')) {
+      if (*CurPtr == '.')
+        ++CurPtr;
+      return LexFloatLiteral();
+    }
+
+    StringRef Result(TokStart, CurPtr - TokStart);
+
+    APInt Value(128, 0, true);
+    if (Result.getAsInteger(Radix, Value))
+      return ReturnError(TokStart, !isHex ? "invalid decimal number" :
+                           "invalid hexdecimal number");
+
+    // Consume the [hH].
+    if (LexMasmIntegers && Radix == 16)
+      ++CurPtr;
+
+    // The darwin/x86 (and x86-64) assembler accepts and ignores type
+    // suffices on integer literals.
+    SkipIgnoredIntegerSuffix(CurPtr);
+
+    return intToken(Result, Value);
+  }
+
+  if (!LexMasmIntegers && ((*CurPtr == 'b') || (*CurPtr == 'B'))) {
+    ++CurPtr;
+    // See if we actually have "0b" as part of something like "jmp 0b\n"
+    if (!isDigit(CurPtr[0])) {
+      --CurPtr;
+      StringRef Result(TokStart, CurPtr - TokStart);
+      return AsmToken(AsmToken::Integer, Result, 0);
+    }
+    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);
+
+    APInt Value(128, 0, true);
+    if (Result.substr(2).getAsInteger(2, Value))
+      return ReturnError(TokStart, "invalid binary number");
+
+    // The darwin/x86 (and x86-64) assembler accepts and ignores ULL and LL
+    // suffixes on integer literals.
+    SkipIgnoredIntegerSuffix(CurPtr);
+
+    return intToken(Result, Value);
+  }
+
+  if ((*CurPtr == 'x') || (*CurPtr == 'X')) {
+    ++CurPtr;
+    const char *NumStart = CurPtr;
+    while (isHexDigit(CurPtr[0]))
+      ++CurPtr;
+
+    // "0x.0p0" is valid, and "0x0p0" (but not "0xp0" for example, which will be
+    // diagnosed by LexHexFloatLiteral).
+    if (CurPtr[0] == '.' || CurPtr[0] == 'p' || CurPtr[0] == 'P')
+      return LexHexFloatLiteral(NumStart == CurPtr);
+
+    // Otherwise requires at least one hex digit.
+    if (CurPtr == NumStart)
+      return ReturnError(CurPtr-2, "invalid hexadecimal number");
+
+    APInt Result(128, 0);
+    if (StringRef(TokStart, CurPtr - TokStart).getAsInteger(0, Result))
+      return ReturnError(TokStart, "invalid hexadecimal number");
+
+    // Consume the optional [hH].
+    if (LexMasmIntegers && (*CurPtr == 'h' || *CurPtr == 'H'))
+      ++CurPtr;
+
+    // The darwin/x86 (and x86-64) assembler accepts and ignores ULL and LL
+    // suffixes on integer literals.
+    SkipIgnoredIntegerSuffix(CurPtr);
+
+    return intToken(StringRef(TokStart, CurPtr - TokStart), Result);
+  }
+
+  // Either octal or hexadecimal.
+  APInt Value(128, 0, true);
+  unsigned Radix = doHexLookAhead(CurPtr, 8, LexMasmIntegers);
+  bool isHex = Radix == 16;
+  StringRef Result(TokStart, CurPtr - TokStart);
+  if (Result.getAsInteger(Radix, Value))
+    return ReturnError(TokStart, !isHex ? "invalid octal number" :
+                       "invalid hexdecimal number");
+
+  // Consume the [hH].
+  if (Radix == 16)
+    ++CurPtr;
+
+  // The darwin/x86 (and x86-64) assembler accepts and ignores ULL and LL
+  // suffixes on integer literals.
+  SkipIgnoredIntegerSuffix(CurPtr);
+
+  return intToken(Result, Value);
+}
+
+/// LexSingleQuote: Integer: 'b'
+AsmToken AsmLexer::LexSingleQuote() {
+  int CurChar = getNextChar();
+
+  if (CurChar == '\\')
+    CurChar = getNextChar();
+
+  if (CurChar == EOF)
+    return ReturnError(TokStart, "unterminated single quote");
+
+  CurChar = getNextChar();
+
+  if (CurChar != '\'')
+    return ReturnError(TokStart, "single quote way too long");
+
+  // The idea here being that 'c' is basically just an integral
+  // constant.
+  StringRef Res = StringRef(TokStart,CurPtr - TokStart);
+  long long Value;
+
+  if (Res.startswith("\'\\")) {
+    char theChar = Res[2];
+    switch (theChar) {
+      default: Value = theChar; break;
+      case '\'': Value = '\''; break;
+      case 't': Value = '\t'; break;
+      case 'n': Value = '\n'; break;
+      case 'b': Value = '\b'; break;
+    }
+  } else
+    Value = TokStart[1];
+
+  return AsmToken(AsmToken::Integer, Res, 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.
+         !isAtStatementSeparator(CurPtr) && // End of statement marker.
+         *CurPtr != '\n' && *CurPtr != '\r' && CurPtr != CurBuf.end()) {
+    ++CurPtr;
+  }
+  return StringRef(TokStart, CurPtr-TokStart);
+}
+
+StringRef AsmLexer::LexUntilEndOfLine() {
+  TokStart = CurPtr;
+
+  while (*CurPtr != '\n' && *CurPtr != '\r' && CurPtr != CurBuf.end()) {
+    ++CurPtr;
+  }
+  return StringRef(TokStart, CurPtr-TokStart);
+}
+
+size_t AsmLexer::peekTokens(MutableArrayRef<AsmToken> Buf,
+                            bool ShouldSkipSpace) {
+  SaveAndRestore<const char *> SavedTokenStart(TokStart);
+  SaveAndRestore<const char *> SavedCurPtr(CurPtr);
+  SaveAndRestore<bool> SavedAtStartOfLine(IsAtStartOfLine);
+  SaveAndRestore<bool> SavedAtStartOfStatement(IsAtStartOfStatement);
+  SaveAndRestore<bool> SavedSkipSpace(SkipSpace, ShouldSkipSpace);
+  SaveAndRestore<bool> SavedIsPeeking(IsPeeking, true);
+  std::string SavedErr = getErr();
+  SMLoc SavedErrLoc = getErrLoc();
+
+  size_t ReadCount;
+  for (ReadCount = 0; ReadCount < Buf.size(); ++ReadCount) {
+    AsmToken Token = LexToken();
+
+    Buf[ReadCount] = Token;
+
+    if (Token.is(AsmToken::Eof))
+      break;
+  }
+
+  SetError(SavedErrLoc, SavedErr);
+  return ReadCount;
+}
+
+bool AsmLexer::isAtStartOfComment(const char *Ptr) {
+  StringRef CommentString = MAI.getCommentString();
+
+  if (CommentString.size() == 1)
+    return CommentString[0] == Ptr[0];
+
+  // Allow # preprocessor commments also be counted as comments for "##" cases
+  if (CommentString[1] == '#')
+    return CommentString[0] == Ptr[0];
+
+  return strncmp(Ptr, CommentString.data(), CommentString.size()) == 0;
+}
+
+bool AsmLexer::isAtStatementSeparator(const char *Ptr) {
+  return strncmp(Ptr, MAI.getSeparatorString(),
+                 strlen(MAI.getSeparatorString())) == 0;
+}
+
+AsmToken AsmLexer::LexToken() {
+  TokStart = CurPtr;
+  // This always consumes at least one character.
+  int CurChar = getNextChar();
+
+  if (!IsPeeking && CurChar == '#' && IsAtStartOfStatement) {
+    // If this starts with a '#', this may be a cpp
+    // hash directive and otherwise a line comment.
+    AsmToken TokenBuf[2];
+    MutableArrayRef<AsmToken> Buf(TokenBuf, 2);
+    size_t num = peekTokens(Buf, true);
+    // There cannot be a space preceding this
+    if (IsAtStartOfLine && num == 2 && TokenBuf[0].is(AsmToken::Integer) &&
+        TokenBuf[1].is(AsmToken::String)) {
+      CurPtr = TokStart; // reset curPtr;
+      StringRef s = LexUntilEndOfLine();
+      UnLex(TokenBuf[1]);
+      UnLex(TokenBuf[0]);
+      return AsmToken(AsmToken::HashDirective, s);
+    }
+    return LexLineComment();
+  }
+
+  if (isAtStartOfComment(TokStart))
+    return LexLineComment();
+
+  if (isAtStatementSeparator(TokStart)) {
+    CurPtr += strlen(MAI.getSeparatorString()) - 1;
+    IsAtStartOfLine = true;
+    IsAtStartOfStatement = true;
+    return AsmToken(AsmToken::EndOfStatement,
+                    StringRef(TokStart, strlen(MAI.getSeparatorString())));
+  }
+
+  // If we're missing a newline at EOF, make sure we still get an
+  // EndOfStatement token before the Eof token.
+  if (CurChar == EOF && !IsAtStartOfStatement) {
+    IsAtStartOfLine = true;
+    IsAtStartOfStatement = true;
+    return AsmToken(AsmToken::EndOfStatement, StringRef(TokStart, 1));
+  }
+  IsAtStartOfLine = false;
+  bool OldIsAtStartOfStatement = IsAtStartOfStatement;
+  IsAtStartOfStatement = false;
+  switch (CurChar) {
+  default:
+    // Handle identifier: [a-zA-Z_.][a-zA-Z0-9_$.@]*
+    if (isalpha(CurChar) || CurChar == '_' || CurChar == '.')
+      return LexIdentifier();
+
+    // Unknown character, emit an error.
+    return ReturnError(TokStart, "invalid character in input");
+  case EOF:
+    IsAtStartOfLine = true;
+    IsAtStartOfStatement = true;
+    return AsmToken(AsmToken::Eof, StringRef(TokStart, 0));
+  case 0:
+  case ' ':
+  case '\t':
+    IsAtStartOfStatement = OldIsAtStartOfStatement;
+    while (*CurPtr == ' ' || *CurPtr == '\t')
+      CurPtr++;
+    if (SkipSpace)
+      return LexToken(); // Ignore whitespace.
+    else
+      return AsmToken(AsmToken::Space, StringRef(TokStart, CurPtr - TokStart));
+  case '\r': {
+    IsAtStartOfLine = true;
+    IsAtStartOfStatement = true;
+    // If this is a CR followed by LF, treat that as one token.
+    if (CurPtr != CurBuf.end() && *CurPtr == '\n')
+      ++CurPtr;
+    return AsmToken(AsmToken::EndOfStatement,
+                    StringRef(TokStart, CurPtr - TokStart));
+  }
+  case '\n':
+    IsAtStartOfLine = true;
+    IsAtStartOfStatement = true;
+    return AsmToken(AsmToken::EndOfStatement, StringRef(TokStart, 1));
+  case ':': return AsmToken(AsmToken::Colon, StringRef(TokStart, 1));
+  case '+': return AsmToken(AsmToken::Plus, StringRef(TokStart, 1));
+  case '~': return AsmToken(AsmToken::Tilde, StringRef(TokStart, 1));
+  case '(': return AsmToken(AsmToken::LParen, StringRef(TokStart, 1));
+  case ')': return AsmToken(AsmToken::RParen, StringRef(TokStart, 1));
+  case '[': return AsmToken(AsmToken::LBrac, StringRef(TokStart, 1));
+  case ']': return AsmToken(AsmToken::RBrac, StringRef(TokStart, 1));
+  case '{': return AsmToken(AsmToken::LCurly, StringRef(TokStart, 1));
+  case '}': return AsmToken(AsmToken::RCurly, StringRef(TokStart, 1));
+  case '*': return AsmToken(AsmToken::Star, StringRef(TokStart, 1));
+  case ',': return AsmToken(AsmToken::Comma, StringRef(TokStart, 1));
+  case '$': return AsmToken(AsmToken::Dollar, StringRef(TokStart, 1));
+  case '@': return AsmToken(AsmToken::At, StringRef(TokStart, 1));
+  case '\\': return AsmToken(AsmToken::BackSlash, StringRef(TokStart, 1));
+  case '=':
+    if (*CurPtr == '=') {
+      ++CurPtr;
+      return AsmToken(AsmToken::EqualEqual, StringRef(TokStart, 2));
+    }
+    return AsmToken(AsmToken::Equal, StringRef(TokStart, 1));
+  case '-':
+    if (*CurPtr == '>') {
+      ++CurPtr;
+      return AsmToken(AsmToken::MinusGreater, StringRef(TokStart, 2));
+    }
+    return AsmToken(AsmToken::Minus, StringRef(TokStart, 1));
+  case '|':
+    if (*CurPtr == '|') {
+      ++CurPtr;
+      return AsmToken(AsmToken::PipePipe, StringRef(TokStart, 2));
+    }
+    return AsmToken(AsmToken::Pipe, StringRef(TokStart, 1));
+  case '^': return AsmToken(AsmToken::Caret, StringRef(TokStart, 1));
+  case '&':
+    if (*CurPtr == '&') {
+      ++CurPtr;
+      return AsmToken(AsmToken::AmpAmp, StringRef(TokStart, 2));
+    }
+    return AsmToken(AsmToken::Amp, StringRef(TokStart, 1));
+  case '!':
+    if (*CurPtr == '=') {
+      ++CurPtr;
+      return AsmToken(AsmToken::ExclaimEqual, StringRef(TokStart, 2));
+    }
+    return AsmToken(AsmToken::Exclaim, StringRef(TokStart, 1));
+  case '%':
+    if (MAI.hasMipsExpressions()) {
+      AsmToken::TokenKind Operator;
+      unsigned OperatorLength;
+
+      std::tie(Operator, OperatorLength) =
+          StringSwitch<std::pair<AsmToken::TokenKind, unsigned>>(
+              StringRef(CurPtr))
+              .StartsWith("call16", {AsmToken::PercentCall16, 7})
+              .StartsWith("call_hi", {AsmToken::PercentCall_Hi, 8})
+              .StartsWith("call_lo", {AsmToken::PercentCall_Lo, 8})
+              .StartsWith("dtprel_hi", {AsmToken::PercentDtprel_Hi, 10})
+              .StartsWith("dtprel_lo", {AsmToken::PercentDtprel_Lo, 10})
+              .StartsWith("got_disp", {AsmToken::PercentGot_Disp, 9})
+              .StartsWith("got_hi", {AsmToken::PercentGot_Hi, 7})
+              .StartsWith("got_lo", {AsmToken::PercentGot_Lo, 7})
+              .StartsWith("got_ofst", {AsmToken::PercentGot_Ofst, 9})
+              .StartsWith("got_page", {AsmToken::PercentGot_Page, 9})
+              .StartsWith("gottprel", {AsmToken::PercentGottprel, 9})
+              .StartsWith("got", {AsmToken::PercentGot, 4})
+              .StartsWith("gp_rel", {AsmToken::PercentGp_Rel, 7})
+              .StartsWith("higher", {AsmToken::PercentHigher, 7})
+              .StartsWith("highest", {AsmToken::PercentHighest, 8})
+              .StartsWith("hi", {AsmToken::PercentHi, 3})
+              .StartsWith("lo", {AsmToken::PercentLo, 3})
+              .StartsWith("neg", {AsmToken::PercentNeg, 4})
+              .StartsWith("pcrel_hi", {AsmToken::PercentPcrel_Hi, 9})
+              .StartsWith("pcrel_lo", {AsmToken::PercentPcrel_Lo, 9})
+              .StartsWith("tlsgd", {AsmToken::PercentTlsgd, 6})
+              .StartsWith("tlsldm", {AsmToken::PercentTlsldm, 7})
+              .StartsWith("tprel_hi", {AsmToken::PercentTprel_Hi, 9})
+              .StartsWith("tprel_lo", {AsmToken::PercentTprel_Lo, 9})
+              .Default({AsmToken::Percent, 1});
+
+      if (Operator != AsmToken::Percent) {
+        CurPtr += OperatorLength - 1;
+        return AsmToken(Operator, StringRef(TokStart, OperatorLength));
+      }
+    }
+    return AsmToken(AsmToken::Percent, StringRef(TokStart, 1));
+  case '/':
+    IsAtStartOfStatement = OldIsAtStartOfStatement;
+    return LexSlash();
+  case '#': return AsmToken(AsmToken::Hash, StringRef(TokStart, 1));
+  case '\'': return LexSingleQuote();
+  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 '<':
+      ++CurPtr;
+      return AsmToken(AsmToken::LessLess, StringRef(TokStart, 2));
+    case '=':
+      ++CurPtr;
+      return AsmToken(AsmToken::LessEqual, StringRef(TokStart, 2));
+    case '>':
+      ++CurPtr;
+      return AsmToken(AsmToken::LessGreater, StringRef(TokStart, 2));
+    default:
+      return AsmToken(AsmToken::Less, StringRef(TokStart, 1));
+    }
+  case '>':
+    switch (*CurPtr) {
+    case '>':
+      ++CurPtr;
+      return AsmToken(AsmToken::GreaterGreater, StringRef(TokStart, 2));
+    case '=':
+      ++CurPtr;
+      return 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.
+  }
+}