[NFC] OSSACanonicalizeOwned: Renamed found defs.

The field is no longer a worklist, just a list of discovered defs.

Author: nate-chandler

include/swift/SILOptimizer/Utils/CanonicalizeOSSALifetime.h

@@ -342,8 +342,8 @@ class CanonicalizeOSSALifetime final {
   };
   friend llvm::DenseMapInfo<Def>;
 
-  /// Visited set for general def-use traversal that prevents revisiting values.
-  llvm::SmallSetVector<Def, 8> defUseWorklist;
+  /// The defs derived from currentDef whose uses are added to liveness.
+  llvm::SmallSetVector<Def, 8> discoveredDefs;
 
   /// The blocks that were discovered by PrunedLiveness.
   SmallVector<SILBasicBlock *, 32> discoveredBlocks;

lib/SILOptimizer/Utils/CanonicalizeOSSALifetime.cpp

@@ -134,11 +134,11 @@ bool CanonicalizeOSSALifetime::computeCanonicalLiveness() {
              getCurrentDef()->print(llvm::dbgs()));
   SmallVector<unsigned, 8> indexWorklist;
   auto addDefToWorklist = [&](Def def) {
-    if (!defUseWorklist.insert(def))
+    if (!discoveredDefs.insert(def))
       return;
-    indexWorklist.push_back(defUseWorklist.size() - 1);
+    indexWorklist.push_back(discoveredDefs.size() - 1);
   };
-  defUseWorklist.clear();
+  discoveredDefs.clear();
   addDefToWorklist(Def::root(getCurrentDef()));
   // Only the first level of reborrows need to be consider. All nested inner
   // adjacent reborrows and phis are encapsulated within their lifetimes.
@@ -151,7 +151,7 @@ bool CanonicalizeOSSALifetime::computeCanonicalLiveness() {
   }
   while (!indexWorklist.empty()) {
     auto index = indexWorklist.pop_back_val();
-    auto def = defUseWorklist[index];
+    auto def = discoveredDefs[index];
     auto value = def.getValue();
     LLVM_DEBUG(llvm::dbgs() << "  Uses of value:\n";
                value->print(llvm::dbgs()));
@@ -1158,14 +1158,14 @@ void CanonicalizeOSSALifetime::rewriteCopies(
     SmallVectorImpl<DestroyValueInst *> const &newDestroys) {
   assert(getCurrentDef()->getOwnershipKind() == OwnershipKind::Owned);
 
-  // Shadow defUseWorklist in order to constrain its uses.
-  auto &defUseWorklist = this->defUseWorklist;
+  // Shadow discoveredDefs in order to constrain its uses.
+  auto &discoveredDefs = this->discoveredDefs;
 
   SmallVector<unsigned, 8> indexWorklist;
   auto addDefToWorklist = [&](Def def) {
-    if (!defUseWorklist.insert(def))
+    if (!discoveredDefs.insert(def))
       return;
-    indexWorklist.push_back(defUseWorklist.size() - 1);
+    indexWorklist.push_back(discoveredDefs.size() - 1);
   };
 
   InstructionSetVector instsToDelete(getCurrentDef()->getFunction());
@@ -1213,13 +1213,13 @@ void CanonicalizeOSSALifetime::rewriteCopies(
     return true;
   };
 
-  defUseWorklist.clear();
+  discoveredDefs.clear();
   addDefToWorklist(Def::root(getCurrentDef()));
   // Perform a def-use traversal, visiting each use operand.
 
   while (!indexWorklist.empty()) {
     auto index = indexWorklist.pop_back_val();
-    auto def = defUseWorklist[index];
+    auto def = discoveredDefs[index];
     switch (def) {
     case Def::Kind::BorrowedFrom:
     case Def::Kind::Reborrow: