[OptTable] Precompute OptTable prefixes union table through tablegen

This avoid rediscovering this table when reading each options, providing
a sensible 2% speedup when processing and empty file, and a measurable
speedup on typical workloads, see:

This is optional, the legacy, on-the-fly, approach can still be used
through the GenericOptTable class, while the new one is used through
PrecomputedOptTable.

https://llvm-compile-time-tracker.com/compare.php?from=4da6cb3202817ee2897d6b690e4af950459caea4&to=19a492b704e8f5c1dea120b9c0d3859bd78796be&stat=instructions:u

Differential Revision: https://reviews.llvm.org/D140800

1 files changed, 4 insertions, 4 deletions

diff --git a/llvm/tools/llvm-rc/llvm-rc.cpp b/llvm/tools/llvm-rc/llvm-rc.cpp
index 6f7cc09..8e525bd 100644
--- a/llvm/tools/llvm-rc/llvm-rc.cpp
+++ b/llvm/tools/llvm-rc/llvm-rc.cpp
@@ -76,9 +76,9 @@ static constexpr opt::OptTable::Info InfoTable[] = {
 };
 } // namespace rc_opt
 
-class RcOptTable : public opt::OptTable {
+class RcOptTable : public opt::GenericOptTable {
 public:
-  RcOptTable() : OptTable(rc_opt::InfoTable, /* IgnoreCase = */ true) {}
+  RcOptTable() : GenericOptTable(rc_opt::InfoTable, /* IgnoreCase = */ true) {}
 };
 
 enum Windres_ID {
@@ -110,10 +110,10 @@ static constexpr opt::OptTable::Info InfoTable[] = {
 };
 } // namespace windres_opt
 
-class WindresOptTable : public opt::OptTable {
+class WindresOptTable : public opt::GenericOptTable {
 public:
   WindresOptTable()
-      : OptTable(windres_opt::InfoTable, /* IgnoreCase = */ false) {}
+      : GenericOptTable(windres_opt::InfoTable, /* IgnoreCase = */ false) {}
 };
 
 static ExitOnError ExitOnErr;