[cfe-commits] r50925 - /cfe/trunk/Driver/RewriteMacros.cpp
Chris Lattner
sabre at nondot.org
Fri May 9 17:02:33 PDT 2008
Author: lattner
Date: Fri May 9 19:02:33 2008
New Revision: 50925
URL: http://llvm.org/viewvc/llvm-project?rev=50925&view=rev
Log:
Implement -rewrite-macros, which is a crazy macro expander that expands
macros but doesn't expand #includes, remove comments, remove #defines
etc.
For example:
----
#include <stdio.h>
#define bbaa
#define funclike(x) x "a" x "b" x
bbaa bbaa
#if 1
funclike("gar")
foo /*blah*/ bar
bar
#endif
#if 0
funclike()
#endif
----
rewrites to:
----
#include <stdio.h>
#define bbaa
#define funclike(x) x "a" x "b" x
/*bbaa bbaa*/
#if 1
"gar" "a" "gar" "b" "gar"/*funclike*//*("gar")*/
foo /*blah*/ bar
bar
#endif
#if 0
/*funclike()*/
#endif
----
Modified:
cfe/trunk/Driver/RewriteMacros.cpp
Modified: cfe/trunk/Driver/RewriteMacros.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/Driver/RewriteMacros.cpp?rev=50925&r1=50924&r2=50925&view=diff
==============================================================================
--- cfe/trunk/Driver/RewriteMacros.cpp (original)
+++ cfe/trunk/Driver/RewriteMacros.cpp Fri May 9 19:02:33 2008
@@ -16,12 +16,33 @@
#include "clang/Rewrite/Rewriter.h"
#include "clang/Lex/Preprocessor.h"
#include "clang/Basic/SourceManager.h"
-#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/Streams.h"
#include "llvm/System/Path.h"
#include <fstream>
using namespace clang;
+/// isSameToken - Return true if the two specified tokens start have the same
+/// content.
+static bool isSameToken(Token &RawTok, Token &PPTok) {
+ if (PPTok.getKind() == RawTok.getKind())
+ return true;
+
+ if (PPTok.getIdentifierInfo() &&
+ PPTok.getIdentifierInfo() == RawTok.getIdentifierInfo())
+ return true;
+
+ return false;
+}
+
+static void GetNextRawTok(Lexer &RawLex, Token &RawTok, Preprocessor &PP) {
+ RawLex.LexRawToken(RawTok);
+
+ // If we have an identifier with no identifier info for our raw token, look
+ // up the indentifier info.
+ if (RawTok.is(tok::identifier) && !RawTok.getIdentifierInfo())
+ RawTok.setIdentifierInfo(PP.LookUpIdentifierInfo(RawTok));
+}
+
/// RewriteMacrosInInput - Implement -rewrite-macros mode.
void clang::RewriteMacrosInInput(Preprocessor &PP,const std::string &InFileName,
const std::string &OutFileName) {
@@ -29,16 +50,112 @@
Rewriter Rewrite;
Rewrite.setSourceMgr(SM);
+ RewriteBuffer &RB = Rewrite.getEditBuffer(SM.getMainFileID());
- // Get the ID and start/end of the main file.
- unsigned MainFileID = SM.getMainFileID();
- //const llvm::MemoryBuffer *MainBuf = SM.getBuffer(MainFileID);
- //const char *MainFileStart = MainBuf->getBufferStart();
- //const char *MainFileEnd = MainBuf->getBufferEnd();
-
+ const SourceManager &SourceMgr = PP.getSourceManager();
+ std::pair<const char*, const char*> File =
+ SourceMgr.getBufferData(SM.getMainFileID());
- // Create the output file.
+ // Create a lexer to lex all the tokens of the main file in raw mode. Even
+ // though it is in raw mode, it will not return comments.
+ Lexer RawLex(SourceLocation::getFileLoc(SM.getMainFileID(), 0),
+ PP.getLangOptions(), File.first, File.second);
+ Token RawTok;
+ GetNextRawTok(RawLex, RawTok, PP);
+
+ // Get the first preprocessing token.
+ PP.EnterMainSourceFile();
+ Token PPTok;
+ PP.Lex(PPTok);
+ // Preprocess the input file in parallel with raw lexing the main file. Ignore
+ // all tokens that are preprocessed from a file other than the main file (e.g.
+ // a header). If we see tokens that are in the preprocessed file bug not the
+ // lexed file, we have a macro expansion. If we see tokens in the lexed file
+ // that aren't in the preprocessed view, we have macros that expand to no
+ // tokens, or macro arguments etc.
+ while (RawTok.isNot(tok::eof) || PPTok.isNot(tok::eof)) {
+ SourceLocation PPLoc = SM.getLogicalLoc(PPTok.getLocation());
+
+ // If PPTok is from a different source file, ignore it.
+ if (!SM.isFromMainFile(PPLoc)) {
+ PP.Lex(PPTok);
+ continue;
+ }
+
+ // If the raw file hits a preprocessor directive, they will be extra tokens
+ // in the input file, but we don't want to treat them as such... just ignore
+ // them.
+ if (RawTok.is(tok::hash) && RawTok.isAtStartOfLine()) {
+ GetNextRawTok(RawLex, RawTok, PP);
+ while (!RawTok.isAtStartOfLine() && RawTok.isNot(tok::eof))
+ GetNextRawTok(RawLex, RawTok, PP);
+ continue;
+ }
+
+ // Okay, both tokens are from the same file. Get their offsets from the
+ // start of the file.
+ unsigned PPOffs = SM.getFullFilePos(PPLoc);
+ unsigned RawOffs = SM.getFullFilePos(RawTok.getLocation());
+
+ // If the offsets are the same and the token kind is the same, ignore them.
+ if (PPOffs == RawOffs && isSameToken(RawTok, PPTok)) {
+ GetNextRawTok(RawLex, RawTok, PP);
+ PP.Lex(PPTok);
+ continue;
+ }
+
+ // If the PP token is farther along than the raw token, something was
+ // deleted. Comment out the raw token.
+ if (RawOffs <= PPOffs) {
+ // Comment out a whole run of tokens instead of bracketing each one with
+ // comments.
+ RB.InsertTextAfter(RawOffs, "/*", 2);
+ unsigned EndPos;
+
+ // Switch on comment lexing. If we get a comment, we don't want to
+ // include it as part of our run of tokens, because we don't want to
+ // nest /* */ comments.
+ RawLex.SetCommentRetentionState(true);
+
+ do {
+ EndPos = RawOffs+RawTok.getLength();
+
+ GetNextRawTok(RawLex, RawTok, PP);
+ RawOffs = SM.getFullFilePos(RawTok.getLocation());
+
+ if (RawTok.is(tok::comment)) {
+ RawLex.SetCommentRetentionState(false);
+ // Skip past the comment.
+ GetNextRawTok(RawLex, RawTok, PP);
+ break;
+ }
+
+ } while (RawOffs <= PPOffs && !RawTok.isAtStartOfLine() &&
+ (PPOffs != RawOffs || !isSameToken(RawTok, PPTok)));
+
+ RawLex.SetCommentRetentionState(false);
+
+ RB.InsertTextBefore(EndPos, "*/", 2);
+ continue;
+ }
+
+ // Otherwise, there was a replacement an expansion. Insert the new token
+ // in the output buffer. Insert the whole run of new tokens at once to get
+ // them in the right order.
+ unsigned InsertPos = PPOffs;
+ std::string Expansion;
+ while (PPOffs < RawOffs) {
+ Expansion += ' ' + PP.getSpelling(PPTok);
+ PP.Lex(PPTok);
+ PPLoc = SM.getLogicalLoc(PPTok.getLocation());
+ PPOffs = SM.getFullFilePos(PPLoc);
+ }
+ Expansion += ' ';
+ RB.InsertTextBefore(InsertPos, &Expansion[0], Expansion.size());
+ }
+
+ // Create the output file.
std::ostream *OutFile;
if (OutFileName == "-") {
OutFile = llvm::cout.stream();
@@ -58,7 +175,7 @@
// Get the buffer corresponding to MainFileID. If we haven't changed it, then
// we are done.
if (const RewriteBuffer *RewriteBuf =
- Rewrite.getRewriteBufferFor(MainFileID)) {
+ Rewrite.getRewriteBufferFor(SM.getMainFileID())) {
//printf("Changed:\n");
*OutFile << std::string(RewriteBuf->begin(), RewriteBuf->end());
} else {
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