+++ /dev/null
-//===-- llvm-mcmarkup.cpp - Parse the MC assembly markup tags -------------===//
-//
-// The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// Example simple parser implementation for the MC assembly markup language.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Support/CommandLine.h"
-#include "llvm/Support/ManagedStatic.h"
-#include "llvm/Support/MemoryBuffer.h"
-#include "llvm/Support/PrettyStackTrace.h"
-#include "llvm/Support/Signals.h"
-#include "llvm/Support/SourceMgr.h"
-#include "llvm/Support/raw_ostream.h"
-using namespace llvm;
-
-static cl::list<std::string>
- InputFilenames(cl::Positional, cl::desc("<input files>"),
- cl::ZeroOrMore);
-static cl::opt<bool>
-DumpTags("dump-tags", cl::desc("List all tags encountered in input"));
-
-static StringRef ToolName;
-
-/// Trivial lexer for the markup parser. Input is always handled a character
-/// at a time. The lexer just encapsulates EOF and lookahead handling.
-class MarkupLexer {
- StringRef::const_iterator Start;
- StringRef::const_iterator CurPtr;
- StringRef::const_iterator End;
-public:
- MarkupLexer(StringRef Source)
- : Start(Source.begin()), CurPtr(Source.begin()), End(Source.end()) {}
- // When processing non-markup, input is consumed a character at a time.
- bool isEOF() { return CurPtr == End; }
- int getNextChar() {
- if (CurPtr == End) return EOF;
- return *CurPtr++;
- }
- int peekNextChar() {
- if (CurPtr == End) return EOF;
- return *CurPtr;
- }
- StringRef::const_iterator getPosition() const { return CurPtr; }
-};
-
-/// A markup tag is a name and a (usually empty) list of modifiers.
-class MarkupTag {
- StringRef Name;
- StringRef Modifiers;
- SMLoc StartLoc;
-public:
- MarkupTag(StringRef n, StringRef m, SMLoc Loc)
- : Name(n), Modifiers(m), StartLoc(Loc) {}
- StringRef getName() const { return Name; }
- StringRef getModifiers() const { return Modifiers; }
- SMLoc getLoc() const { return StartLoc; }
-};
-
-/// A simple parser implementation for creating MarkupTags from input text.
-class MarkupParser {
- MarkupLexer &Lex;
- SourceMgr &SM;
-public:
- MarkupParser(MarkupLexer &lex, SourceMgr &SrcMgr) : Lex(lex), SM(SrcMgr) {}
- /// Create a MarkupTag from the current position in the MarkupLexer.
- /// The parseTag() method should be called when the lexer has processed
- /// the opening '<' character. Input will be consumed up to and including
- /// the ':' which terminates the tag open.
- MarkupTag parseTag();
- /// Issue a diagnostic and terminate program execution.
- void FatalError(SMLoc Loc, StringRef Msg);
-};
-
-void MarkupParser::FatalError(SMLoc Loc, StringRef Msg) {
- SM.PrintMessage(Loc, SourceMgr::DK_Error, Msg);
- exit(1);
-}
-
-// Example handler for when a tag is recognized.
-static void processStartTag(MarkupTag &Tag) {
- // If we're just printing the tags, do that, otherwise do some simple
- // colorization.
- if (DumpTags) {
- outs() << Tag.getName();
- if (Tag.getModifiers().size())
- outs() << " " << Tag.getModifiers();
- outs() << "\n";
- return;
- }
-
- if (!outs().has_colors())
- return;
- // Color registers as red and immediates as cyan. Those don't have nested
- // tags, so don't bother keeping a stack of colors to reset to.
- if (Tag.getName() == "reg")
- outs().changeColor(raw_ostream::RED);
- else if (Tag.getName() == "imm")
- outs().changeColor(raw_ostream::CYAN);
-}
-
-// Example handler for when the end of a tag is recognized.
-static void processEndTag(MarkupTag &Tag) {
- // If we're printing the tags, there's nothing more to do here. Otherwise,
- // set the color back the normal.
- if (DumpTags)
- return;
- if (!outs().has_colors())
- return;
- // Just reset to basic white.
- outs().changeColor(raw_ostream::WHITE, false);
-}
-
-MarkupTag MarkupParser::parseTag() {
- // First off, extract the tag into it's own StringRef so we can look at it
- // outside of the context of consuming input.
- StringRef::const_iterator Start = Lex.getPosition();
- SMLoc Loc = SMLoc::getFromPointer(Start - 1);
- while(Lex.getNextChar() != ':') {
- // EOF is an error.
- if (Lex.isEOF())
- FatalError(SMLoc::getFromPointer(Start), "unterminated markup tag");
- }
- StringRef RawTag(Start, Lex.getPosition() - Start - 1);
- std::pair<StringRef, StringRef> SplitTag = RawTag.split(' ');
- return MarkupTag(SplitTag.first, SplitTag.second, Loc);
-}
-
-static void parseMCMarkup(StringRef Filename) {
- ErrorOr<std::unique_ptr<MemoryBuffer>> BufferPtr =
- MemoryBuffer::getFileOrSTDIN(Filename);
- if (std::error_code EC = BufferPtr.getError()) {
- errs() << ToolName << ": " << EC.message() << '\n';
- return;
- }
- std::unique_ptr<MemoryBuffer> &Buffer = BufferPtr.get();
-
- SourceMgr SrcMgr;
-
- StringRef InputSource = Buffer->getBuffer();
-
- // Tell SrcMgr about this buffer, which is what the parser will pick up.
- SrcMgr.AddNewSourceBuffer(std::move(Buffer), SMLoc());
-
- MarkupLexer Lex(InputSource);
- MarkupParser Parser(Lex, SrcMgr);
-
- SmallVector<MarkupTag, 4> TagStack;
-
- for (int CurChar = Lex.getNextChar();
- CurChar != EOF;
- CurChar = Lex.getNextChar()) {
- switch (CurChar) {
- case '<': {
- // A "<<" is output as a literal '<' and does not start a markup tag.
- if (Lex.peekNextChar() == '<') {
- (void)Lex.getNextChar();
- break;
- }
- // Parse the markup entry.
- TagStack.push_back(Parser.parseTag());
-
- // Do any special handling for the start of a tag.
- processStartTag(TagStack.back());
- continue;
- }
- case '>': {
- SMLoc Loc = SMLoc::getFromPointer(Lex.getPosition() - 1);
- // A ">>" is output as a literal '>' and does not end a markup tag.
- if (Lex.peekNextChar() == '>') {
- (void)Lex.getNextChar();
- break;
- }
- // Close out the innermost tag.
- if (TagStack.empty())
- Parser.FatalError(Loc, "'>' without matching '<'");
-
- // Do any special handling for the end of a tag.
- processEndTag(TagStack.back());
-
- TagStack.pop_back();
- continue;
- }
- default:
- break;
- }
- // For anything else, just echo the character back out.
- if (!DumpTags && CurChar != EOF)
- outs() << (char)CurChar;
- }
-
- // If there are any unterminated markup tags, issue diagnostics for them.
- while (!TagStack.empty()) {
- MarkupTag &Tag = TagStack.back();
- SrcMgr.PrintMessage(Tag.getLoc(), SourceMgr::DK_Error,
- "unterminated markup tag");
- TagStack.pop_back();
- }
-}
-
-int main(int argc, char **argv) {
- // Print a stack trace if we signal out.
- sys::PrintStackTraceOnErrorSignal(argv[0]);
- PrettyStackTraceProgram X(argc, argv);
-
- llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
- cl::ParseCommandLineOptions(argc, argv, "llvm MC markup parser\n");
-
- ToolName = argv[0];
-
- // If no input files specified, read from stdin.
- if (InputFilenames.size() == 0)
- InputFilenames.push_back("-");
-
- llvm::for_each(InputFilenames, parseMCMarkup);
- return 0;
-}
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