Revert of Remove SIMD.js from V8.

src/full-codegen/s390/full-codegen-s390.cc

Index: src/full-codegen/s390/full-codegen-s390.cc
diff --git a/src/full-codegen/s390/full-codegen-s390.cc b/src/full-codegen/s390/full-codegen-s390.cc
index 418e19d742245f079812532f79eb7fb58b90185c..215a2c560136c841d95081ba6d35f158713c56a5 100644
--- a/src/full-codegen/s390/full-codegen-s390.cc
+++ b/src/full-codegen/s390/full-codegen-s390.cc
@@ -2562,6 +2562,16 @@
     __ tm(FieldMemOperand(r2, Map::kBitFieldOffset),
           Operand((1 << Map::kIsCallable) | (1 << Map::kIsUndetectable)));
     Split(eq, if_true, if_false, fall_through);
+// clang-format off
+#define SIMD128_TYPE(TYPE, Type, type, lane_count, lane_type)   \
+  } else if (String::Equals(check, factory->type##_string())) { \
+    __ JumpIfSmi(r2, if_false);                                 \
+    __ LoadP(r2, FieldMemOperand(r2, HeapObject::kMapOffset));  \
+    __ CompareRoot(r2, Heap::k##Type##MapRootIndex);            \
+    Split(eq, if_true, if_false, fall_through);
+  SIMD128_TYPES(SIMD128_TYPE)
+#undef SIMD128_TYPE
+    // clang-format on
   } else {
     if (if_false != fall_through) __ b(if_false);
   }