[interpreter] Add support for scalable operands.

test/unittests/interpreter/constant-array-builder-unittest.cc

 // Copyright 2014 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.
 
 #include "src/v8.h"
 
 #include "src/factory.h"
 #include "src/handles-inl.h"
 #include "src/interpreter/constant-array-builder.h"
 #include "src/isolate.h"
@@ skipping 91 matching lines @@
       Handle<Object> object =
           isolate()->factory()->NewNumberFromSize(2 * k8BitCapacity + i);
       size_t index = builder.CommitReservedEntry(OperandSize::kByte, object);
       CHECK_EQ(static_cast<int>(index), k8BitCapacity - reserved + i);
       CHECK(builder.At(static_cast<int>(index))->SameValue(*object));
     }
     CHECK_EQ(builder.size(), 2 * k8BitCapacity + reserved);
   }
 }
 
-
-TEST_F(ConstantArrayBuilderTest, AllocateEntriesWithIdx16Reservations) {
+TEST_F(ConstantArrayBuilderTest, AllocateEntriesWithWideReservations) {
   for (size_t reserved = 1; reserved < k8BitCapacity; reserved *= 3) {
     ConstantArrayBuilder builder(isolate(), zone());
     for (size_t i = 0; i < k8BitCapacity; i++) {
       Handle<Object> object = isolate()->factory()->NewNumberFromSize(i);
       builder.Insert(object);
       CHECK(builder.At(i)->SameValue(*object));
       CHECK_EQ(builder.size(), i + 1);
     }
     for (size_t i = 0; i < reserved; i++) {
       OperandSize operand_size = builder.CreateReservedEntry();
@@ skipping 30 matching lines @@
     builder.Insert(object);
     CHECK(builder.At(i)->SameValue(*object));
   }
   Handle<FixedArray> constant_array = builder.ToFixedArray();
   CHECK_EQ(constant_array->length(), kNumberOfElements);
   for (size_t i = 0; i < kNumberOfElements; i++) {
     CHECK(constant_array->get(static_cast<int>(i))->SameValue(*builder.At(i)));
   }
 }
 
+TEST_F(ConstantArrayBuilderTest, ToLargeFixedArray) {

[rmcilroy, 2016/03/17 17:30:50]

How long does this tests take to run? We previously had issues with the 16bit
varient, just want to make sure this doesn't regress test runtime again.

[oth, 2016/03/21 09:16:54]

Good point. I did check but think we'd need to test this either way as there was
a mistake that this catches.

Debug.x64 on MBA 2.13 GHz reports 34-38ms.

+  ConstantArrayBuilder builder(isolate(), zone());
+  static const size_t kNumberOfElements = 37373;
+  for (size_t i = 0; i < kNumberOfElements; i++) {
+    Handle<Object> object = isolate()->factory()->NewNumberFromSize(i);
+    builder.Insert(object);
+    CHECK(builder.At(i)->SameValue(*object));
+  }
+  Handle<FixedArray> constant_array = builder.ToFixedArray();
+  CHECK_EQ(constant_array->length(), kNumberOfElements);
+  for (size_t i = 0; i < kNumberOfElements; i++) {
+    CHECK(constant_array->get(static_cast<int>(i))->SameValue(*builder.At(i)));
+  }
+}
 
 TEST_F(ConstantArrayBuilderTest, GapFilledWhenLowReservationCommitted) {
   ConstantArrayBuilder builder(isolate(), zone());
   for (size_t i = 0; i < k8BitCapacity; i++) {
     OperandSize operand_size = builder.CreateReservedEntry();
     CHECK(OperandSize::kByte == operand_size);
     CHECK_EQ(builder.size(), 0);
   }
   for (size_t i = 0; i < k8BitCapacity; i++) {
     Handle<Object> object = isolate()->factory()->NewNumberFromSize(i);
@@ skipping 37 matching lines @@
     Handle<Object> original = builder.At(k8BitCapacity + i);
     CHECK(original->SameValue(*reference));
     Handle<Object> duplicate = builder.At(i);
     CHECK(duplicate->SameValue(*isolate()->factory()->the_hole_value()));
   }
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8