[PCH] Add an option to not write comments into PCH
Summary:
Will be used in clangd, see the follow-up change.
Clangd does not use comments read from PCH to avoid crashes due to
changed contents of the file. However, reading them considerably slows
down code completion on files with large preambles.
Reviewers: sammccall
Reviewed By: sammccall
Subscribers: ioeric, cfe-commits
Differential Revision: https://reviews.llvm.org/D48942
llvm-svn: 336539
diff --git a/clang/lib/Serialization/ASTWriter.cpp b/clang/lib/Serialization/ASTWriter.cpp
index 279960a..bc569d1 100644
--- a/clang/lib/Serialization/ASTWriter.cpp
+++ b/clang/lib/Serialization/ASTWriter.cpp
@@ -78,6 +78,7 @@
#include "llvm/ADT/Optional.h"
#include "llvm/ADT/PointerIntPair.h"
#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/ScopeExit.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/SmallVector.h"
@@ -3252,6 +3253,9 @@
void ASTWriter::WriteComments() {
Stream.EnterSubblock(COMMENTS_BLOCK_ID, 3);
+ auto _ = llvm::make_scope_exit([this] { Stream.ExitBlock(); });
+ if (!PP->getPreprocessorOpts().WriteCommentListToPCH)
+ return;
ArrayRef<RawComment *> RawComments = Context->Comments.getComments();
RecordData Record;
for (const auto *I : RawComments) {
@@ -3262,7 +3266,6 @@
Record.push_back(I->isAlmostTrailingComment());
Stream.EmitRecord(COMMENTS_RAW_COMMENT, Record);
}
- Stream.ExitBlock();
}
//===----------------------------------------------------------------------===//