Avoid copying the data of in-memory preambles
Summary: Preambles are large and we should avoid copying them.
Reviewers: bkramer, klimek
Reviewed By: bkramer
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D40302
llvm-svn: 318945
diff --git a/clang/lib/Frontend/PrecompiledPreamble.cpp b/clang/lib/Frontend/PrecompiledPreamble.cpp
index 130b904..c6ee4d0 100644
--- a/clang/lib/Frontend/PrecompiledPreamble.cpp
+++ b/clang/lib/Frontend/PrecompiledPreamble.cpp
@@ -699,9 +699,7 @@
StringRef PCHPath = getInMemoryPreamblePath();
PreprocessorOpts.ImplicitPCHInclude = PCHPath;
- // FIMXE(ibiryukov): Preambles can be large. We should allow shared access
- // to the preamble data instead of copying it here.
- auto Buf = llvm::MemoryBuffer::getMemBufferCopy(Storage.asMemory().Data);
+ auto Buf = llvm::MemoryBuffer::getMemBuffer(Storage.asMemory().Data);
VFS = createVFSOverlayForPreamblePCH(PCHPath, std::move(Buf), VFS);
}
}