[clang-tools-extra] [clangd] Re-land "support outgoing calls in call hierarchy" (PR #117673)

[kadir çetinkaya via cfe-commits]

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@@ -149,15 +150,18 @@ void Dex::buildIndex() {
   InvertedIndex = std::move(Builder).build();
 
   // Build RevRefs
-  for (const auto &[ID, RefList] : Refs)
-    for (const auto &R : RefList)
-      if ((R.Kind & ContainedRefsRequest::SupportedRefKinds) !=
-          RefKind::Unknown)
-        RevRefs.emplace_back(R, ID);
-  // Sort by container ID so we can use binary search for lookup.
-  llvm::sort(RevRefs, [](const RevRef &A, const RevRef &B) {
-    return A.ref().Container < B.ref().Container;
-  });
+  if (Config::current().CallHierarchy.OutgoingCalls) {
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kadircet wrote:

nit: early exit

https://github.com/llvm/llvm-project/pull/117673