Merge pull request #38220 from atrick/rewrite-borrow-forward

Copy propagation redesign and the CanonicalizeBorrowScopes utility

Author: atrick

include/swift/Basic/DAGNodeWorklist.h

@@ -0,0 +1,64 @@
+//===--- DAGNodeWorklist.h --------------------------------------*- C++ -*-===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SWIFT_BASIC_DAGNODEWORKLIST_H
+#define SWIFT_BASIC_DAGNODEWORKLIST_H
+
+#include "swift/Basic/LLVM.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/SmallVector.h"
+
+/// Worklist of pointer-like things that have an invalid default value. This not
+/// only avoids duplicates in the worklist, but also avoids revisiting
+/// already-popped nodes. This makes it suitable for DAG traversal. This can
+/// also be used within hybrid worklist/recursive traversal by recording the
+/// size of the worklist at each level of recursion.
+///
+/// The primary API has two methods: intialize() and pop(). Others are provided
+/// for flexibility.
+template <typename T, unsigned SmallSize> struct DAGNodeWorklist {
+  llvm::SmallPtrSet<T, SmallSize> nodeVisited;
+  llvm::SmallVector<T, SmallSize> nodeVector;
+
+  DAGNodeWorklist() = default;
+
+  DAGNodeWorklist(const DAGNodeWorklist &) = delete;
+
+  void initialize(T t) {
+    clear();
+    insert(t);
+  }
+
+  template <typename R> void initializeRange(R &&range) {
+    clear();
+    nodeVisited.insert(range.begin(), range.end());
+    nodeVector.append(range.begin(), range.end());
+  }
+
+  T pop() { return empty() ? T() : nodeVector.pop_back_val(); }
+
+  bool empty() const { return nodeVector.empty(); }
+
+  unsigned size() const { return nodeVector.size(); }
+
+  void clear() {
+    nodeVector.clear();
+    nodeVisited.clear();
+  }
+
+  void insert(T t) {
+    if (nodeVisited.insert(t).second)
+      nodeVector.push_back(t);
+  }
+};
+
+#endif // SWIFT_BASIC_DAGNODEWORKLIST_H

include/swift/SIL/SILValue.h

@@ -478,6 +478,8 @@ class ValueBase : public SILNode, public SILAllocated<ValueBase> {
   /// For instruction results, this returns getDefiningInstruction(). For
   /// arguments, this returns SILBasicBlock::begin() for the argument's parent
   /// block. Returns nullptr for SILUndef.
+  ///
+  /// FIXME: remove this redundant API from SILValue.
   SILInstruction *getDefiningInsertionPoint();
 
   // Const version of \see getDefiningInsertionPoint.
@@ -614,8 +616,6 @@ class SILValue {
 
   /// If this SILValue is a result of an instruction, return its
   /// defining instruction. Returns nullptr otherwise.
-  ///
-  /// FIXME: remove this redundant API from SILValue.
   SILInstruction *getDefiningInstruction() {
     return Value->getDefiningInstruction();
   }

include/swift/SILOptimizer/Analysis/NonLocalAccessBlockAnalysis.h

@@ -88,7 +88,10 @@ class NonLocalAccessBlockAnalysis
       virtual void verify(NonLocalAccessBlocks *accessBlocks) const override {
         NonLocalAccessBlocks checkAccessBlocks(accessBlocks->function);
         checkAccessBlocks.compute();
-        assert(checkAccessBlocks.accessBlocks == accessBlocks->accessBlocks);
+        assert(llvm::all_of(checkAccessBlocks.accessBlocks,
+                            [&](SILBasicBlock *bb) {
+                              return accessBlocks->accessBlocks.count(bb);
+                            }));
       })
 };