Limit size of dehoistable array indices

src/elements-kind.cc

Index: src/elements-kind.cc
diff --git a/src/elements-kind.cc b/src/elements-kind.cc
index 16f5bff98bdfc77b67e18f883efebe45f9624030..689c2205696689e82dd45bfb6a67d92a8c3f5099 100644
--- a/src/elements-kind.cc
+++ b/src/elements-kind.cc
@@ -35,6 +35,36 @@ namespace v8 {
 namespace internal {
 
 
+int ElementsKindToShiftSize(ElementsKind elements_kind) {
+  switch (elements_kind) {
+    case EXTERNAL_BYTE_ELEMENTS:
+    case EXTERNAL_PIXEL_ELEMENTS:
+    case EXTERNAL_UNSIGNED_BYTE_ELEMENTS:
+      return 0;
+    case EXTERNAL_SHORT_ELEMENTS:
+    case EXTERNAL_UNSIGNED_SHORT_ELEMENTS:
+      return 1;
+    case EXTERNAL_INT_ELEMENTS:
+    case EXTERNAL_UNSIGNED_INT_ELEMENTS:
+    case EXTERNAL_FLOAT_ELEMENTS:
+      return 2;
+    case EXTERNAL_DOUBLE_ELEMENTS:
+    case FAST_DOUBLE_ELEMENTS:
+    case FAST_HOLEY_DOUBLE_ELEMENTS:
+      return 3;
+    case FAST_SMI_ELEMENTS:
+    case FAST_ELEMENTS:
+    case FAST_HOLEY_SMI_ELEMENTS:
+    case FAST_HOLEY_ELEMENTS:
+    case DICTIONARY_ELEMENTS:
+    case NON_STRICT_ARGUMENTS_ELEMENTS:
+      return kPointerSizeLog2;
+  }
+  UNREACHABLE();
+  return 0;
+}
+
+
 const char* ElementsKindToString(ElementsKind kind) {
   ElementsAccessor* accessor = ElementsAccessor::ForKind(kind);
   return accessor->name();