[interpreter] Use hashmap for ConstantArrayBuilder's constant map

src/interpreter/constant-array-builder.h

Index: src/interpreter/constant-array-builder.h
diff --git a/src/interpreter/constant-array-builder.h b/src/interpreter/constant-array-builder.h
index 2018f256931c8e6cc18e95c5738f0d4bbc77eae7..63dc24151cf77f62814344eb7fdfee136b217e0d 100644
--- a/src/interpreter/constant-array-builder.h
+++ b/src/interpreter/constant-array-builder.h
@@ -6,6 +6,7 @@
 #define V8_INTERPRETER_CONSTANT_ARRAY_BUILDER_H_
 
 #include "src/identity-map.h"
+#include "src/inline-hash-map.h"
 #include "src/interpreter/bytecodes.h"
 #include "src/zone-containers.h"
 
@@ -16,6 +17,14 @@ class Isolate;
 
 namespace interpreter {
 
+// Hashing function specifically for addresses
+struct AddressHash {
+  size_t operator()(Address address) const {
+    // Divide by 8, then knuth multiplicative hash

[rmcilroy, 2016/09/12 14:17:31]

Should we divide 8 or by kPointerSize? 

+    return (bit_cast<size_t>(address) >> 3) * 2654435761;
+  }
+};
+
 // 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
@@ -108,7 +117,7 @@ class ConstantArrayBuilder final BASE_EMBEDDED {
   Handle<Object> the_hole_value() const { return the_hole_value_; }
 
   ConstantArraySlice* idx_slice_[3];
-  ZoneMap<Address, index_t> constants_map_;
+  ZoneInlineHashMap<Address, index_t, AddressHash> constants_map_;
   ZoneMap<Smi*, index_t> smi_map_;
   ZoneVector<std::pair<Smi*, index_t>> smi_pairs_;
   Handle<Object> the_hole_value_;