PTH:
- Added a side-table per each token-cached file with the preprocessor conditional stack. This tracks what #if's are matched with what #endifs and where their respective tokens are in the PTH file. This will allow for quick skipping of excluded conditional branches in the Preprocessor.
- Performance testing shows the addition of this information (without actually utilizing it) leads to no performance regressions.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@60911 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Driver/CacheTokens.cpp b/Driver/CacheTokens.cpp
index ceb16b0..21e5ee0 100644
--- a/Driver/CacheTokens.cpp
+++ b/Driver/CacheTokens.cpp
@@ -27,7 +27,7 @@
typedef uint32_t Offset;
-typedef llvm::DenseMap<const FileEntry*,Offset> PCHMap;
+typedef llvm::DenseMap<const FileEntry*,std::pair<Offset,Offset> > PCHMap;
typedef llvm::DenseMap<const IdentifierInfo*,uint32_t> IDMap;
static void Emit32(llvm::raw_ostream& Out, uint32_t V) {
@@ -140,18 +140,25 @@
unsigned size = strlen(Name);
Emit32(Out, size);
EmitBuf(Out, Name, Name+size);
- Emit32(Out, I->second);
+ Emit32(Out, I->second.first);
+ Emit32(Out, I->second.second);
}
return off;
}
-static Offset LexTokens(llvm::raw_fd_ostream& Out, Lexer& L, Preprocessor& PP,
- uint32_t& idcount, IDMap& IM) {
+static std::pair<Offset,Offset>
+LexTokens(llvm::raw_fd_ostream& Out, Lexer& L, Preprocessor& PP,
+ uint32_t& idcount, IDMap& IM) {
// Record the location within the token file.
Offset off = (Offset) Out.tell();
SourceManager& SMgr = PP.getSourceManager();
+
+ // Keep track of matching '#if' ... '#endif'.
+ typedef std::vector<std::pair<Offset, unsigned> > PPCondTable;
+ PPCondTable PPCond;
+ std::vector<unsigned> PPStartCond;
Token Tok;
@@ -164,6 +171,7 @@
else if (Tok.is(tok::hash) && Tok.isAtStartOfLine()) {
// Special processing for #include. Store the '#' token and lex
// the next token.
+ Offset HashOff = (Offset) Out.tell();
EmitToken(Out, Tok, SMgr, idcount, IM);
L.LexFromRawLexer(Tok);
@@ -189,11 +197,52 @@
if (Tok.is(tok::identifier))
Tok.setIdentifierInfo(PP.LookUpIdentifierInfo(Tok));
}
+ else if (K == tok::pp_if || K == tok::pp_ifdef || K == tok::pp_ifndef) {
+ // Ad an entry for '#if' and friends. We initially set the target index
+ // to 0. This will get backpatched when we hit #endif.
+ PPStartCond.push_back(PPCond.size());
+ PPCond.push_back(std::make_pair((Offset) HashOff, 0U));
+ }
+ else if (K == tok::pp_endif) {
+ assert(!PPStartCond.empty());
+ // Add an entry for '#endif'. We set the target table index to itself.
+ unsigned index = PPCond.size();
+ PPCond.push_back(std::make_pair((Offset) HashOff, index));
+ // Backpatch the opening '#if' entry.
+ assert(PPCond[PPStartCond.back()].second == 0);
+ PPCond[PPStartCond.back()].second = index;
+ PPStartCond.pop_back();
+ }
+ else if (K == tok::pp_elif) {
+ assert(!PPStartCond.empty());
+ // Add an entry for '#elif'. This serves as both a closing and
+ // opening of a conditional block. This means that its entry
+ // will get backpatched later.
+ unsigned index = PPCond.size();
+ PPCond.push_back(std::make_pair((Offset) HashOff, 0U));
+ // Backpatch the previous '#if' entry.
+ assert(PPCond[PPStartCond.back()].second == 0);
+ PPCond[PPStartCond.back()].second = index;
+ PPStartCond.pop_back();
+ // Now add '#elif' as a new block opening.
+ PPStartCond.push_back(index);
+ }
}
}
while (EmitToken(Out, Tok, SMgr, idcount, IM), Tok.isNot(tok::eof));
+
+ // Next write out PPCond.
+ Offset PPCondOff = (Offset) Out.tell();
+ // Write out the size of PPCond so that clients can tell if the table is
+ // empty.
+ Emit32(Out, PPCond.size());
- return off;
+ for (PPCondTable::iterator I=PPCond.begin(), E=PPCond.end(); I!=E; ++I) {
+ Emit32(Out, I->first - off);
+ Emit32(Out, I->second);
+ }
+
+ return std::make_pair(off,PPCondOff);
}
void clang::CacheTokens(Preprocessor& PP, const std::string& OutFile) {
@@ -243,7 +292,7 @@
Lexer L(SourceLocation::getFileLoc(I.getFileID(), 0), LOpts,
B->getBufferStart(), B->getBufferEnd(), B);
-
+
PM[FE] = LexTokens(Out, L, PP, idcount, IM);
}