MIPS: Support fast case for-in in Crankshaft.
Port r10794 (
654fe910).
Original commit message:
Only JSObject enumerables with enum cache (fast case properties, no interceptors, no enumerable properties on the prototype) are supported.
HLoadKeyedGeneric with keys produced by for-in enumeration are recognized and rewritten into direct property load by index. For this enum-cache was extended to store property indices in a separate array (see handles.cc).
New hydrogen instructions:
- HForInPrepareMap: checks for-in fast case preconditions and returns map that contains enum-cache;
- HForInCacheArray: extracts enum-cache array from the map;
- HCheckMapValue: map check with HValue map instead of immediate;
- HLoadFieldByIndex: load fast property by it's index, positive indexes denote in-object properties, negative - out of object properties;
Changed hydrogen instructions:
- HLoadKeyedFastElement: added hole check suppression for loads from internal FixedArrays that are knows to have no holes inside.
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/9453009
Patch from Daniel Kalmar <kalmard@homejinni.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10865
ce2b1a6d-e550-0410-aec6-
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