Add codegen support to the optimizing compiler.

Change-Id: I9aae76908ff1d6e64fb71a6718fc1426b67a5c28
diff --git a/compiler/optimizing/code_generator.h b/compiler/optimizing/code_generator.h
new file mode 100644
index 0000000..2a5ae7d
--- /dev/null
+++ b/compiler/optimizing/code_generator.h
@@ -0,0 +1,82 @@
+/*
+ * 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.
+ */
+
+#ifndef ART_COMPILER_OPTIMIZING_CODE_GENERATOR_H_
+#define ART_COMPILER_OPTIMIZING_CODE_GENERATOR_H_
+
+#include "instruction_set.h"
+#include "memory_region.h"
+#include "nodes.h"
+#include "utils/assembler.h"
+
+namespace art {
+
+class CodeAllocator {
+ public:
+  CodeAllocator() { }
+  virtual ~CodeAllocator() { }
+
+  virtual uint8_t* Allocate(size_t size) = 0;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(CodeAllocator);
+};
+
+class CodeGenerator : public HGraphVisitor {
+ public:
+  // Compiles the graph to executable instructions. Returns whether the compilation
+  // succeeded.
+  static bool CompileGraph(
+      HGraph* graph, InstructionSet instruction_set, CodeAllocator* allocator);
+
+  Assembler* assembler() const { return assembler_; }
+
+  // Visit functions for instruction classes.
+#define DECLARE_VISIT_INSTRUCTION(name)     \
+  virtual void Visit##name(H##name* instr) = 0;
+
+  FOR_EACH_INSTRUCTION(DECLARE_VISIT_INSTRUCTION)
+
+#undef DECLARE_VISIT_INSTRUCTION
+
+ protected:
+  CodeGenerator(Assembler* assembler, HGraph* graph)
+      : HGraphVisitor(graph), assembler_(assembler), block_labels_(graph->arena(), 0) {
+    block_labels_.SetSize(graph->blocks()->Size());
+  }
+
+  Label* GetLabelOf(HBasicBlock* block) const;
+  bool GoesToNextBlock(HGoto* got) const;
+
+ private:
+  virtual void GenerateFrameEntry() = 0;
+  virtual void GenerateFrameExit() = 0;
+  virtual void Bind(Label* label) = 0;
+
+  void Compile(CodeAllocator* allocator);
+  void CompileBlock(HBasicBlock* block);
+
+  Assembler* const assembler_;
+
+  // Labels for each block that will be compiled.
+  GrowableArray<Label> block_labels_;
+
+  DISALLOW_COPY_AND_ASSIGN(CodeGenerator);
+};
+
+}  // namespace art
+
+#endif  // ART_COMPILER_OPTIMIZING_CODE_GENERATOR_H_