Re-apply: Initial check-in of an optimizing compiler.

The classes and the names are very much inspired by V8/Dart.
It currently only supports the RETURN_VOID dex instruction,
and there is a pretty printer to check if the building of the
graph is correct.

Change-Id: I28e125dfee86ae6ec9b3fec6aa1859523b92a893
diff --git a/compiler/optimizing/pretty_printer_test.cc b/compiler/optimizing/pretty_printer_test.cc
new file mode 100644
index 0000000..81a0d91
--- /dev/null
+++ b/compiler/optimizing/pretty_printer_test.cc
@@ -0,0 +1,87 @@
+/*
+ * 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 "base/stringprintf.h"
+#include "builder.h"
+#include "dex_instruction.h"
+#include "nodes.h"
+#include "pretty_printer.h"
+#include "utils/arena_allocator.h"
+
+#include "gtest/gtest.h"
+
+namespace art {
+
+const uint16_t data[] = { Instruction::RETURN_VOID };
+
+const char* expected =
+    "BasicBlock 0\n"
+    "  Goto\n"
+    "BasicBlock 1\n"
+    "  ReturnVoid\n"
+    "BasicBlock 2\n"
+    "  Exit\n";
+
+class StringPrettyPrinter : public HPrettyPrinter {
+ public:
+  explicit StringPrettyPrinter(HGraph* graph) : HPrettyPrinter(graph), str_("") { }
+
+  virtual void PrintInt(int value) {
+    str_ += StringPrintf("%d", value);
+  }
+
+  virtual void PrintString(const char* value) {
+    str_ += value;
+  }
+
+  virtual void PrintNewLine() {
+    str_ += '\n';
+  }
+
+  void Clear() { str_.clear(); }
+
+  std::string str() const { return str_; }
+
+ private:
+  std::string str_;
+  DISALLOW_COPY_AND_ASSIGN(StringPrettyPrinter);
+};
+
+TEST(OptimizerTest, ReturnVoid) {
+  ArenaPool pool;
+  ArenaAllocator allocator(&pool);
+  HGraphBuilder builder(&allocator);
+  HGraph* graph = builder.BuildGraph(data, data + 1);
+  ASSERT_NE(graph, nullptr);
+  StringPrettyPrinter printer(graph);
+  printer.VisitInsertionOrder();
+  ASSERT_STREQ(expected, printer.str().c_str());
+
+  const GrowableArray<HBasicBlock*>* blocks = graph->blocks();
+  ASSERT_EQ(blocks->Get(0)->predecessors()->Size(), (size_t)0);
+  ASSERT_EQ(blocks->Get(1)->predecessors()->Size(), (size_t)1);
+  ASSERT_EQ(blocks->Get(1)->predecessors()->Get(0), blocks->Get(0));
+  ASSERT_EQ(blocks->Get(2)->predecessors()->Size(), (size_t)1);
+  ASSERT_EQ(blocks->Get(2)->predecessors()->Get(0), blocks->Get(1));
+
+  ASSERT_EQ(blocks->Get(0)->successors()->Size(), (size_t)1);
+  ASSERT_EQ(blocks->Get(1)->successors()->Get(0), blocks->Get(2));
+  ASSERT_EQ(blocks->Get(1)->successors()->Size(), (size_t)1);
+  ASSERT_EQ(blocks->Get(1)->successors()->Get(0), blocks->Get(2));
+  ASSERT_EQ(blocks->Get(2)->successors()->Size(), (size_t)0);
+}
+
+}  // namespace art