Move SourcePosition into separate header file.

src/source-position.h

Index: src/source-position.h
diff --git a/src/source-position.h b/src/source-position.h
new file mode 100644
index 0000000000000000000000000000000000000000..46ee9820b2cd1fa708ca785ffe03864fb3634795
--- /dev/null
+++ b/src/source-position.h
@@ -0,0 +1,87 @@
+// Copyright 2016 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef V8_SOURCE_POSITION_H_
+#define V8_SOURCE_POSITION_H_
+
+#include <ostream>
+
+#include "src/assembler.h"
+#include "src/flags.h"
+#include "src/utils.h"
+
+namespace v8 {
+namespace internal {
+
+// This class encapsulates encoding and decoding of sources positions from
+// which hydrogen values originated.
+// When FLAG_track_hydrogen_positions is set this object encodes the
+// identifier of the inlining and absolute offset from the start of the
+// inlined function.
+// When the flag is not set we simply track absolute offset from the
+// script start.
+class SourcePosition {
+ public:
+  static SourcePosition Unknown() {
+    return SourcePosition::FromRaw(kNoPosition);
+  }
+
+  bool IsUnknown() const { return value_ == kNoPosition; }
+
+  uint32_t position() const { return PositionField::decode(value_); }
+  void set_position(uint32_t position) {
+    if (FLAG_hydrogen_track_positions) {
+      value_ = static_cast<uint32_t>(PositionField::update(value_, position));
+    } else {
+      value_ = position;
+    }
+  }
+
+  uint32_t inlining_id() const { return InliningIdField::decode(value_); }
+  void set_inlining_id(uint32_t inlining_id) {
+    if (FLAG_hydrogen_track_positions) {
+      value_ =
+          static_cast<uint32_t>(InliningIdField::update(value_, inlining_id));
+    }
+  }
+
+  uint32_t raw() const { return value_; }
+
+ private:
+  static const uint32_t kNoPosition =
+      static_cast<uint32_t>(RelocInfo::kNoPosition);
+  typedef BitField<uint32_t, 0, 9> InliningIdField;
+
+  // Offset from the start of the inlined function.
+  typedef BitField<uint32_t, 9, 23> PositionField;
+
+  friend class HPositionInfo;
+  friend class Deoptimizer;
+
+  static SourcePosition FromRaw(uint32_t raw_position) {
+    SourcePosition position;
+    position.value_ = raw_position;
+    return position;
+  }
+
+  // If FLAG_hydrogen_track_positions is set contains bitfields InliningIdField
+  // and PositionField.
+  // Otherwise contains absolute offset from the script start.
+  uint32_t value_;
+};
+
+inline std::ostream& operator<<(std::ostream& os, const SourcePosition& p) {
+  if (p.IsUnknown()) {
+    return os << "<?>";
+  } else if (FLAG_hydrogen_track_positions) {
+    return os << "<" << p.inlining_id() << ":" << p.position() << ">";
+  } else {
+    return os << "<0:" << p.raw() << ">";
+  }
+}
+
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_SOURCE_POSITION_H_