[interpreter] Streamline bytecode array writing.

src/interpreter/bytecode-array-writer.h

Index: src/interpreter/bytecode-array-writer.h
diff --git a/src/interpreter/bytecode-array-writer.h b/src/interpreter/bytecode-array-writer.h
index 76d881ed58be4835df8372ec9e516278875d22dc..251edcd96e439a967e70a5d82ca90a70eaa71fc8 100644
--- a/src/interpreter/bytecode-array-writer.h
+++ b/src/interpreter/bytecode-array-writer.h
@@ -34,6 +34,13 @@ class BytecodeArrayWriter final : public BytecodePipelineStage {
       Handle<FixedArray> handler_table) override;
 
  private:
+  // Maximum sized packed bytecode is comprised of a prefix bytecode,
+  // plus the actual bytecode, plus the maximum number of operands times
+  // the maximum operand size.
+  static const size_t kMaxSizeOfPackedBytecode =
+      2 * sizeof(Bytecode) +
+      Bytecodes::kMaxOperands * sizeof(static_cast<size_t>(OperandSize::kLast));

[rmcilroy, 2016/06/28 09:07:26]

I don't think you want the sizeof here any longer, OperandSize::kLast gives you
the size directly

+
   // Constants that act as placeholders for jump operands to be
   // patched. These have operand sizes that match the sizes of
   // reserved constant pool entries.