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| author | Duncan P. N. Exon Smith <dexonsmith@apple.com> | 2016-04-20 20:14:09 +0000 |
|---|---|---|
| committer | Duncan P. N. Exon Smith <dexonsmith@apple.com> | 2016-04-20 20:14:09 +0000 |
| commit | 3c406c2da52302eb5cced431373f240b9c037841 (patch) | |
| tree | 0036fa3b9a770cedd54db3a83bfd890cb2799c2a /llvm/lib/Bitcode/Reader/BitcodeReader.cpp | |
| parent | 07320e403001cc192f8565d77001d281d41f4572 (diff) | |
| download | bcm5719-llvm-3c406c2da52302eb5cced431373f240b9c037841.tar.gz bcm5719-llvm-3c406c2da52302eb5cced431373f240b9c037841.zip | |
IR: Use SmallVector instead of std::vector of TrackingMDRef
Don't use std::vector<TrackingMDRef>, since (at least in some versions
of libc++) std::vector apparently copies values on grow operations
instead of moving them. Found this when I was temporarily deleting the
copy constructor for TrackingMDRef to investigate a performance
bottleneck.
llvm-svn: 266909
Diffstat (limited to 'llvm/lib/Bitcode/Reader/BitcodeReader.cpp')
| -rw-r--r-- | llvm/lib/Bitcode/Reader/BitcodeReader.cpp | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp index 9c65eecad81..ae1f98f0fd6 100644 --- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp +++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp @@ -107,7 +107,12 @@ class BitcodeReaderMetadataList { bool AnyFwdRefs; unsigned MinFwdRef; unsigned MaxFwdRef; - std::vector<TrackingMDRef> MetadataPtrs; + + /// Array of metadata references. + /// + /// Don't use std::vector here. Some versions of libc++ copy (instead of + /// move) on resize, and TrackingMDRef is very expensive to copy. + SmallVector<TrackingMDRef, 1> MetadataPtrs; LLVMContext &Context; public: |
