[CopyPropagation] Replace LexicalDestroyHoisting with OwnedLifetimeCanonicalization.

include/swift/SIL/PrunedLiveness.h

@@ -590,6 +590,8 @@ struct PrunedLivenessBoundary {
 ///
 ///   bool isDef(SILInstruction *inst) const
 ///
+///   bool isDef(SILArgument *arg) const
+///
 ///   bool isDefBlock(SILBasicBlock *block) const
 ///
 template <typename LivenessWithDefs>
@@ -611,6 +613,15 @@ class PrunedLiveRange : public PrunedLiveness {
                                            ValueSet &visited,
                                            SILValue value);
 
+  bool isInstructionLive(SILInstruction *instruction, bool liveOut) const;
+  bool isAvailableOut(SILBasicBlock *block, DeadEndBlocks &deadEndBlocks) const;
+  bool isInstructionAvailable(SILInstruction *user,
+                              DeadEndBlocks &deadEndBlocks) const;
+  /// Whether \p user is within the boundary extended from live regions into
+  /// dead-end regions up to the availability boundary.
+  bool isWithinExtendedBoundary(SILInstruction *user,
+                                DeadEndBlocks *deadEndBlocks) const;
+
 public:
   /// Add \p inst to liveness which uses the def as indicated by \p usage.
   void updateForUse(SILInstruction *inst, LifetimeEnding usage);
@@ -735,6 +746,8 @@ class SSAPrunedLiveness : public PrunedLiveRange<SSAPrunedLiveness> {
 
   bool isDef(SILInstruction *inst) const { return inst == defInst; }
 
+  bool isDef(SILArgument *arg) const { return def == arg; }
+
   bool isDefBlock(SILBasicBlock *block) const {
     return def->getParentBlock() == block;
   }

include/swift/SILOptimizer/Utils/CanonicalizeBorrowScope.h

@@ -168,12 +168,6 @@ bool shrinkBorrowScope(
 MoveValueInst *foldDestroysOfCopiedLexicalBorrow(BeginBorrowInst *bbi,
                                                  DominanceInfo &dominanceTree,
                                                  InstructionDeleter &deleter);
-
-bool hoistDestroysOfOwnedLexicalValue(SILValue const value,
-                                      SILFunction &function,
-                                      InstructionDeleter &deleter,
-                                      BasicCalleeAnalysis *calleeAnalysis);
-
 } // namespace swift
 
 #endif // SWIFT_SILOPTIMIZER_UTILS_CANONICALIZEBORROWSCOPES_H

include/swift/SILOptimizer/Utils/CanonicalizeOSSALifetime.h

@@ -100,6 +100,7 @@
 #include "swift/Basic/SmallPtrSetVector.h"
 #include "swift/SIL/PrunedLiveness.h"
 #include "swift/SIL/SILInstruction.h"
+#include "swift/SILOptimizer/Analysis/DeadEndBlocksAnalysis.h"
 #include "swift/SILOptimizer/Analysis/DominanceAnalysis.h"
 #include "swift/SILOptimizer/Analysis/NonLocalAccessBlockAnalysis.h"
 #include "swift/SILOptimizer/Utils/InstructionDeleter.h"
@@ -247,6 +248,8 @@ class CanonicalizeOSSALifetime final {
   // extendLivenessThroughOverlappingAccess is invoked.
   NonLocalAccessBlocks *accessBlocks = nullptr;
 
+  DeadEndBlocksAnalysis *deadEndBlocksAnalysis;
+
   DominanceInfo *domTree = nullptr;
 
   BasicCalleeAnalysis *calleeAnalysis;
@@ -326,27 +329,22 @@ class CanonicalizeOSSALifetime final {
     }
   };
 
-  CanonicalizeOSSALifetime(PruneDebugInsts_t pruneDebugMode,
-                           MaximizeLifetime_t maximizeLifetime,
-                           SILFunction *function,
-                           NonLocalAccessBlockAnalysis *accessBlockAnalysis,
-                           DominanceInfo *domTree,
-                           BasicCalleeAnalysis *calleeAnalysis,
-                           InstructionDeleter &deleter)
+  CanonicalizeOSSALifetime(
+      PruneDebugInsts_t pruneDebugMode, MaximizeLifetime_t maximizeLifetime,
+      SILFunction *function, NonLocalAccessBlockAnalysis *accessBlockAnalysis,
+      DeadEndBlocksAnalysis *deadEndBlocksAnalysis, DominanceInfo *domTree,
+      BasicCalleeAnalysis *calleeAnalysis, InstructionDeleter &deleter)
       : pruneDebugMode(pruneDebugMode), maximizeLifetime(maximizeLifetime),
-        accessBlockAnalysis(accessBlockAnalysis), domTree(domTree),
+        accessBlockAnalysis(accessBlockAnalysis),
+        deadEndBlocksAnalysis(deadEndBlocksAnalysis), domTree(domTree),
         calleeAnalysis(calleeAnalysis), deleter(deleter) {}
 
   SILValue getCurrentDef() const { return currentDef; }
 
   void initializeLiveness(SILValue def,
                           ArrayRef<SILInstruction *> lexicalLifetimeEnds) {
     assert(consumingBlocks.empty() && debugValues.empty());
-    // Clear the cached analysis pointer just in case the client invalidates the
-    // analysis, freeing its memory.
-    accessBlocks = nullptr;
-    consumes.clear();
-    destroys.clear();
+    clear();
 
     currentDef = def;
     currentLexicalLifetimeEnds = lexicalLifetimeEnds;
@@ -358,9 +356,18 @@ class CanonicalizeOSSALifetime final {
   }
 
   void clear() {
+    // Clear the access blocks analysis pointer in case the client invalidates
+    // the analysis.  If the client did, the analysis will be recomputed in
+    // extendLivenessThroughOverlappingAccess; if it didn't, the analysis
+    // pointer will just be set back to its old value when the analysis' cache
+    // is consulted in extendLivenessThroughOverlappingAccess.
+    accessBlocks = nullptr;
+
     consumingBlocks.clear();
     debugValues.clear();
     discoveredBlocks.clear();
+    consumes.clear();
+    destroys.clear();
   }
 
   /// Top-Level API: rewrites copies and destroys within \p def's extended
@@ -472,7 +479,7 @@ class CanonicalizeOSSALifetime final {
   void findExtendedBoundary(PrunedLivenessBoundary const &originalBoundary,
                             PrunedLivenessBoundary &boundary);
 
-  void findDestroysOutsideBoundary(SmallVectorImpl<SILInstruction *> &destroys);
+  void extendLivenessToDeadEnds();
   void extendLivenessToDeinitBarriers();
 
   void extendUnconsumedLiveness(PrunedLivenessBoundary const &boundary);
@@ -481,9 +488,10 @@ class CanonicalizeOSSALifetime final {
       llvm::function_ref<void(SILInstruction *, PrunedLiveness::LifetimeEnding)>
           visitor);
 
-  void insertDestroysOnBoundary(PrunedLivenessBoundary const &boundary);
+  void insertDestroysOnBoundary(PrunedLivenessBoundary const &boundary,
+                                SmallVectorImpl<DestroyValueInst *> &destroys);
 
-  void rewriteCopies();
+  void rewriteCopies(SmallVectorImpl<DestroyValueInst *> const &destroys);
 };
 
 } // end namespace swift