MIPS: port Add complete ElementsKind information directly to Map for objects with elements.

src/mips/full-codegen-mips.cc

Index: src/mips/full-codegen-mips.cc
diff --git a/src/mips/full-codegen-mips.cc b/src/mips/full-codegen-mips.cc
index b085859d00bd2a6194d210ad7d749ff69cdd10ad..f8803e47a31af03d7698c54d8bbfa346ce9b979c 100644
--- a/src/mips/full-codegen-mips.cc
+++ b/src/mips/full-codegen-mips.cc
@@ -3444,9 +3444,7 @@ void FullCodeGenerator::EmitFastAsciiArrayJoin(ZoneList<Expression*>* args) {
   __ Branch(&bailout, ne, scratch2, Operand(JS_ARRAY_TYPE));
 
   // Check that the array has fast elements.
-  __ lbu(scratch2, FieldMemOperand(scratch1, Map::kBitField2Offset));
-  __ And(scratch3, scratch2, Operand(1 << Map::kHasFastElements));
-  __ Branch(&bailout, eq, scratch3, Operand(zero_reg));
+  __ CheckFastElements(scratch1, scratch2, &bailout);
 
   // If the array has length zero, return the empty string.
   __ lw(array_length, FieldMemOperand(array, JSArray::kLengthOffset));