[PATCH] D127006: [pseudo] Invert rows/columns of LRTable storage for speedup. NFC

[Sam McCall via Phabricator via cfe-commits]

sammccall created this revision.
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There are more states than symbols.
This means first partioning the action list by state leaves us with a smaller
range to binary search over. This improves find() a lot and glrParse() by 7%.
The tradeoff is storing more smaller ranges increases the size of the offsets
array, overall grammar memory is +1% (337->340KB).

Before:
glrParse    188795975 ns    188778003 ns           77 bytes_per_second=1.98068M/s
After:
glrParse    175936203 ns    175916873 ns           81 bytes_per_second=2.12548M/s


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D127006

Files:
  clang-tools-extra/pseudo/include/clang-pseudo/LRTable.h
  clang-tools-extra/pseudo/lib/grammar/LRTable.cpp
  clang-tools-extra/pseudo/lib/grammar/LRTableBuild.cpp
  clang-tools-extra/pseudo/tool/ClangPseudo.cpp

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