[interpreter] Preparation for 32-bit operands.

src/interpreter/constant-array-builder.h

 // Copyright 2015 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_INTERPRETER_CONSTANT_ARRAY_BUILDER_H_
 #define V8_INTERPRETER_CONSTANT_ARRAY_BUILDER_H_
 
 #include "src/identity-map.h"
 #include "src/interpreter/bytecodes.h"
 #include "src/zone-containers.h"
 
 namespace v8 {
 namespace internal {
 
 class Isolate;
 
 namespace interpreter {
 
 // A helper class for constructing constant arrays for the
 // interpreter. Each instance of this class is intended to be used to
 // generate exactly one FixedArray of constants via the ToFixedArray
 // method.
 class ConstantArrayBuilder final BASE_EMBEDDED {
  public:
   // Capacity of the 8-bit operand slice.
-  static const size_t kLowCapacity = 1u << kBitsPerByte;
-
-  // Capacity of the combined 8-bit and 16-bit operand slices.
-  static const size_t kMaxCapacity = 1u << (2 * kBitsPerByte);
+  static const size_t k8BitCapacity = 1u << kBitsPerByte;
 
   // Capacity of the 16-bit operand slice.
-  static const size_t kHighCapacity = kMaxCapacity - kLowCapacity;
+  static const size_t k16BitCapacity = (1u << 2 * kBitsPerByte) - k8BitCapacity;
+
+  // Capacity of the 32-bit operand slice.
+  static const size_t k32BitCapacity =
+      kMaxUInt32 - k16BitCapacity - k8BitCapacity + 1;
 
   ConstantArrayBuilder(Isolate* isolate, Zone* zone);
 
   // Generate a fixed array of constants based on inserted objects.
   Handle<FixedArray> ToFixedArray();
 
   // Returns the object in the constant pool array that at index
   // |index|.
   Handle<Object> At(size_t index) const;
 
@@ skipping 10 matching lines @@
   OperandSize CreateReservedEntry();
 
   // Commit reserved entry and returns the constant pool index for the
   // object.
   size_t CommitReservedEntry(OperandSize operand_size, Handle<Object> object);
 
   // Discards constant pool reservation.
   void DiscardReservedEntry(OperandSize operand_size);
 
  private:
-  typedef uint16_t index_t;
+  typedef uint32_t index_t;
 
   index_t AllocateEntry(Handle<Object> object);
 
-  struct ConstantArraySlice final {
-    ConstantArraySlice(Zone* zone, size_t start_index, size_t capacity);
+  struct ConstantArraySlice final : public ZoneObject {
+    ConstantArraySlice(Zone* zone, size_t start_index, size_t capacity,
+                       OperandSize operand_size);
     void Reserve();
     void Unreserve();
     size_t Allocate(Handle<Object> object);
     Handle<Object> At(size_t index) const;
 
     inline size_t available() const { return capacity() - reserved() - size(); }
     inline size_t reserved() const { return reserved_; }
     inline size_t capacity() const { return capacity_; }
     inline size_t size() const { return constants_.size(); }
     inline size_t start_index() const { return start_index_; }
+    inline size_t max_index() const { return start_index_ + capacity() - 1; }
+    inline OperandSize operand_size() const { return operand_size_; }
 
    private:
     const size_t start_index_;
     const size_t capacity_;
     size_t reserved_;
+    OperandSize operand_size_;
     ZoneVector<Handle<Object>> constants_;
 
     DISALLOW_COPY_AND_ASSIGN(ConstantArraySlice);
   };
 
+  const ConstantArraySlice* IndexToSlice(size_t index) const;
+  ConstantArraySlice* OperandSizeToSlice(OperandSize operand_size) const;
+
   IdentityMap<index_t>* constants_map() { return &constants_map_; }
 
   Isolate* isolate_;
-  ConstantArraySlice idx8_slice_;
-  ConstantArraySlice idx16_slice_;
+  ConstantArraySlice* idx_slice_[2];
   IdentityMap<index_t> constants_map_;
 };
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_INTERPRETER_CONSTANT_ARRAY_BUILDER_H_