Import Dart's parallel move resolver.

And write a few tests while at it.

A parallel move resolver will be needed for performing multiple moves
that are conceptually parallel, for example moves at a block
exit that branches to a block with phi nodes.

Change-Id: Ib95b247b4fc3f2c2fcab3b8c8d032abbd6104cd7

1 files changed, 128 insertions, 0 deletions

diff --git a/compiler/optimizing/parallel_move_test.cc b/compiler/optimizing/parallel_move_test.cc
new file mode 100644
index 0000000..88df24d
--- /dev/null
+++ b/compiler/optimizing/parallel_move_test.cc
@@ -0,0 +1,128 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "nodes.h"
+#include "parallel_move_resolver.h"
+#include "utils/arena_allocator.h"
+
+#include "gtest/gtest.h"
+
+namespace art {
+
+class TestParallelMoveResolver : public ParallelMoveResolver {
+ public:
+  explicit TestParallelMoveResolver(ArenaAllocator* allocator) : ParallelMoveResolver(allocator) {}
+
+  virtual void EmitMove(size_t index) {
+    MoveOperands* move = moves_.Get(index);
+    if (!message_.str().empty()) {
+      message_ << " ";
+    }
+    message_ << "("
+             << move->GetSource().reg().RegId()
+             << " -> "
+             << move->GetDestination().reg().RegId()
+             << ")";
+  }
+
+  virtual void EmitSwap(size_t index) {
+    MoveOperands* move = moves_.Get(index);
+    if (!message_.str().empty()) {
+      message_ << " ";
+    }
+    message_ << "("
+             << move->GetSource().reg().RegId()
+             << " <-> "
+             << move->GetDestination().reg().RegId()
+             << ")";
+  }
+
+  std::string GetMessage() const {
+    return  message_.str();
+  }
+
+ private:
+  std::ostringstream message_;
+
+
+  DISALLOW_COPY_AND_ASSIGN(TestParallelMoveResolver);
+};
+
+static HParallelMove* BuildParallelMove(ArenaAllocator* allocator,
+                                        const size_t operands[][2],
+                                        size_t number_of_moves) {
+  HParallelMove* moves = new (allocator) HParallelMove(allocator);
+  for (size_t i = 0; i < number_of_moves; ++i) {
+    moves->AddMove(new (allocator) MoveOperands(
+        Location::RegisterLocation(ManagedRegister(operands[i][0])),
+        Location::RegisterLocation(ManagedRegister(operands[i][1]))));
+  }
+  return moves;
+}
+
+TEST(ParallelMoveTest, Dependency) {
+  ArenaPool pool;
+  ArenaAllocator allocator(&pool);
+
+  {
+    TestParallelMoveResolver resolver(&allocator);
+    static constexpr size_t moves[][2] = {{0, 1}, {1, 2}};
+    resolver.EmitNativeCode(BuildParallelMove(&allocator, moves, arraysize(moves)));
+    ASSERT_STREQ("(1 -> 2) (0 -> 1)", resolver.GetMessage().c_str());
+  }
+
+  {
+    TestParallelMoveResolver resolver(&allocator);
+    static constexpr size_t moves[][2] = {{0, 1}, {1, 2}, {2, 3}, {1, 4}};
+    resolver.EmitNativeCode(BuildParallelMove(&allocator, moves, arraysize(moves)));
+    ASSERT_STREQ("(2 -> 3) (1 -> 2) (1 -> 4) (0 -> 1)", resolver.GetMessage().c_str());
+  }
+}
+
+TEST(ParallelMoveTest, Swap) {
+  ArenaPool pool;
+  ArenaAllocator allocator(&pool);
+
+  {
+    TestParallelMoveResolver resolver(&allocator);
+    static constexpr size_t moves[][2] = {{0, 1}, {1, 0}};
+    resolver.EmitNativeCode(BuildParallelMove(&allocator, moves, arraysize(moves)));
+    ASSERT_STREQ("(1 <-> 0)", resolver.GetMessage().c_str());
+  }
+
+  {
+    TestParallelMoveResolver resolver(&allocator);
+    static constexpr size_t moves[][2] = {{0, 1}, {1, 2}, {1, 0}};
+    resolver.EmitNativeCode(BuildParallelMove(&allocator, moves, arraysize(moves)));
+    ASSERT_STREQ("(1 -> 2) (1 <-> 0)", resolver.GetMessage().c_str());
+  }
+
+  {
+    TestParallelMoveResolver resolver(&allocator);
+    static constexpr size_t moves[][2] = {{0, 1}, {1, 2}, {2, 3}, {3, 4}, {4, 1}};
+    resolver.EmitNativeCode(BuildParallelMove(&allocator, moves, arraysize(moves)));
+    ASSERT_STREQ("(4 <-> 1) (3 <-> 4) (2 <-> 3) (0 -> 1)", resolver.GetMessage().c_str());
+  }
+
+  {
+    TestParallelMoveResolver resolver(&allocator);
+    static constexpr size_t moves[][2] = {{0, 1}, {1, 2}, {2, 3}, {3, 4}, {4, 1}, {5, 4}};
+    resolver.EmitNativeCode(BuildParallelMove(&allocator, moves, arraysize(moves)));
+    ASSERT_STREQ("(4 <-> 1) (3 <-> 4) (2 <-> 3) (0 -> 1) (5 -> 4)", resolver.GetMessage().c_str());
+  }
+}
+
+}  // namespace art