[CopyPropagation] Destroy hoist -> canonicalize.

Replace usages of lexical destroy hoisting with owned value
canonicalization now that the latter supports lexical values.

Author: nate-chandler

lib/SILOptimizer/Transforms/CopyPropagation.cpp

@@ -503,8 +503,9 @@ void CopyPropagation::run() {
     bool firstRun = true;
     // Run the sequence of utilities:
     // - ShrinkBorrowScope
-    // - CanonicalizeOSSALifetime
+    // - CanonicalizeOSSALifetime(borrowee)
     // - LexicalDestroyFolding
+    // - CanonicalizeOSSALifetime(folded)
     // at least once and then until each stops making changes.
     while (true) {
       SmallVector<CopyValueInst *, 4> modifiedCopyValueInsts;
@@ -529,8 +530,7 @@ void CopyPropagation::run() {
       auto folded = foldDestroysOfCopiedLexicalBorrow(bbi, *domTree, deleter);
       if (!folded)
         break;
-      auto hoisted =
-          hoistDestroysOfOwnedLexicalValue(folded, *f, deleter, calleeAnalysis);
+      auto hoisted = canonicalizer.canonicalizeValueLifetime(folded);
       // Keep running even if the new move's destroys can't be hoisted.
       (void)hoisted;
       eliminateRedundantMove(folded, deleter, defWorklist);
@@ -542,7 +542,7 @@ void CopyPropagation::run() {
   }
   for (auto *argument : f->getArguments()) {
     if (argument->getOwnershipKind() == OwnershipKind::Owned) {
-      hoistDestroysOfOwnedLexicalValue(argument, *f, deleter, calleeAnalysis);
+      canonicalizer.canonicalizeValueLifetime(argument);
     }
   }
   deleter.cleanupDeadInstructions();

test/SILOptimizer/shrink_borrow_scope.sil

@@ -558,8 +558,8 @@ exit:
 // CHECK:         [[LIFETIME_D:%[^,]+]] = begin_borrow [[INSTANCE_D]]
 // CHECK:         struct $CDCase ([[LIFETIME_C]] : $C, [[LIFETIME_D]] : $D)
 // CHECK:         end_borrow [[LIFETIME_D]]
-// CHECK:         destroy_value [[INSTANCE_D]]
 // CHECK:         end_borrow [[LIFETIME_C]]
+// CHECK:         destroy_value [[INSTANCE_D]]
 // CHECK:         return [[COPY_C]]
 // CHECK-LABEL: } // end sil function 'hoist_over_struct'
 sil [ossa] @hoist_over_struct : $@convention(thin) (@owned C, @owned D) -> @owned C {

test/SILOptimizer/shrink_borrow_scope.swift

@@ -27,10 +27,10 @@ public func eliminate_copy_of_returned_then_consumed_owned_value(arg: __owned An
   // no copy of 'x'
   _ = consumeAndProduce(x)
   // CHECK:       [[RESULT:%[^,]+]] = apply {{%[^,]+}}([[MOVE_X]])
-  // release result
   // release arg
-  // CHECK:       destroy_value [[ARG]]
+  // release result
   // CHECK:       destroy_value [[RESULT]]
+  // CHECK:       destroy_value [[ARG]]
   // CHECK-LABEL: } // end sil function 'eliminate_copy_of_returned_then_consumed_owned_value'
 }