Switch SmallSetVector to use DenseSet when it overflows its inline space.

Summary:
SetVector already used DenseSet, but SmallSetVector used std::set.  This
leads to surprising performance differences.  Moreover, it means that
the set of key types accepted by SetVector and SmallSetVector are
quite different!

In order to make this change, we had to convert some callsites that used
SmallSetVector<std::string, N> to use SmallSetVector<CachedHashString, N>
instead.

Reviewers: timshen

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D25648

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@284887 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 4 insertions, 2 deletions

diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index 03d400b9ca..3f2e303b5c 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -1432,7 +1432,8 @@ static void ParseHeaderSearchArgs(HeaderSearchOptions &Opts, ArgList &Args) {
 
   for (const Arg *A : Args.filtered(OPT_fmodules_ignore_macro)) {
     StringRef MacroDef = A->getValue();
-    Opts.ModulesIgnoreMacros.insert(MacroDef.split('=').first);
+    Opts.ModulesIgnoreMacros.insert(
+        llvm::CachedHashString(MacroDef.split('=').first));
   }
 
   // Add -I..., -F..., and -index-header-map options in order.
@@ -2519,7 +2520,8 @@ std::string CompilerInvocation::getModuleHash() const {
     if (!hsOpts.ModulesIgnoreMacros.empty()) {
       // Check whether we're ignoring this macro.
       StringRef MacroDef = I->first;
-      if (hsOpts.ModulesIgnoreMacros.count(MacroDef.split('=').first))
+      if (hsOpts.ModulesIgnoreMacros.count(
+              llvm::CachedHashString(MacroDef.split('=').first)))
         continue;
     }