Optimize testing for an index's existence in packed Arrays

src/runtime/runtime.h

Index: src/runtime/runtime.h
diff --git a/src/runtime/runtime.h b/src/runtime/runtime.h
index 481cf4392054a8f772f6afd9970aa0f3a3138c45..faf3521d60db0db9e18d209fe4bd49f329e00dbe 100644
--- a/src/runtime/runtime.h
+++ b/src/runtime/runtime.h
@@ -704,7 +704,8 @@ namespace internal {
   F(RegExpConstructResult, 3, 1)                            \
   F(GetFromCache, 2, 1)                                     \
   F(NumberToString, 1, 1)                                   \
-  F(DebugIsActive, 0, 1)
+  F(DebugIsActive, 0, 1)                                    \
+  F(HasFastPackedElements, 1, 1)

[Dmitry Lomov (no reviews), 2014/11/27 07:17:54]

Is it critical for HasFastPackedElements to be INLINE_FUNCTION instead of
INLINE_OPTIMIZED_FUNCTION (see below, line 718)? 
If you use runtime function in full codegen, you will save yourself from having
to write all those tedious Emit functions in all the ports

[adamk, 2014/12/02 19:36:20]

Not sure what counts as "critical". Sure, the implementations are a bit tedious,
but they're straightforward enough, so I don't see much point in penalizing full
codegen if I can make them fast.

 
 
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