art: Refactor RuntimeOptions/ParsedOptions

Refactor the RuntimeOptions to be a
type-safe map (VariantMap, see runtime_options.h) and the ParsedOptions
to delegate the parsing to CmdlineParser (see cmdline/cmdline_parser.h).

This is the start of a command line parsing refactor, and may include
more in the future (dex2oat, patchoat, etc).

For more details of the command line parsing generator usage see cmdline/README.md

Change-Id: Ic67c6bca5e1f33bf2ec60e2e3ff8c366bab91563
diff --git a/cmdline/memory_representation.h b/cmdline/memory_representation.h
new file mode 100644
index 0000000..93387de
--- /dev/null
+++ b/cmdline/memory_representation.h
@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2015 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_CMDLINE_MEMORY_REPRESENTATION_H_
+#define ART_CMDLINE_MEMORY_REPRESENTATION_H_
+
+#include <string>
+#include <assert.h>
+#include <ostream>
+#include "utils.h"
+
+namespace art {
+
+// An integral representation of bytes of memory.
+// The underlying runtime size_t value is guaranteed to be a multiple of Divisor.
+template <size_t Divisor = 1024>
+struct Memory {
+  static_assert(IsPowerOfTwo(Divisor), "Divisor must be a power of 2");
+
+  static Memory<Divisor> FromBytes(size_t bytes) {
+    assert(bytes % Divisor == 0);
+    return Memory<Divisor>(bytes);
+  }
+
+  Memory() : Value(0u) {}
+  Memory(size_t value) : Value(value) {  // NOLINT [runtime/explicit] [5]
+    assert(value % Divisor == 0);
+  }
+  operator size_t() const { return Value; }
+
+  size_t ToBytes() const {
+    return Value;
+  }
+
+  static constexpr size_t kDivisor = Divisor;
+
+  static const char* Name() {
+    static std::string str;
+    if (str.empty()) {
+      str = "Memory<" + std::to_string(Divisor) + '>';
+    }
+
+    return str.c_str();
+  }
+
+  size_t Value;
+};
+
+template <size_t Divisor>
+std::ostream& operator<<(std::ostream& stream, Memory<Divisor> memory) {
+  return stream << memory.Value << '*' << Divisor;
+}
+
+using MemoryKiB = Memory<1024>;
+
+}  // namespace art
+
+#endif  // ART_CMDLINE_MEMORY_REPRESENTATION_H_