This reverts commit 5cafecf9f952818400fa32645695e79838f1bc2c.
Buildbots are not happy with the patch.
Lots of crashes and assertion failures such as
llvm::LegalizeRuleSet &llvm::LegalizerInfo::getActionDefinitionsBuilder(
std::initializer_list<unsigned int>): Assertion `Opcodes.size() >= 2 &&
"Initializer list must have at least two opcodes"' failed.