message: Remove shl/shr special handling for 128bit ints
  Cranelift now natively supports 128bit int shifting
diff: @@ -19,9 +19,6 @@ pub(crate) fn maybe_codegen<'tcx>(
  return None;
  }
  - let lhs_val = lhs.load_scalar(fx);
  - let rhs_val = rhs.load_scalar(fx);
  -
  let is_signed = type_sign(lhs.layout().ty);
  match bin_op {
  @@ -128,40 +125,6 @@ pub(crate) fn maybe_codegen<'tcx>(
  assert!(!checked);
  None
  }
  - BinOp::Shl | BinOp::Shr => {
  - let is_overflow = if checked {
  - // rhs >= 128
  -
  - // FIXME support non 128bit rhs
  - /*let (rhs_lsb, rhs_msb) = fx.bcx.ins().isplit(rhs_val);
  - let rhs_msb_gt_0 = fx.bcx.ins().icmp_imm(IntCC::NotEqual, rhs_msb, 0);
  - let rhs_lsb_ge_128 = fx.bcx.ins().icmp_imm(IntCC::SignedGreaterThan, rhs_lsb, 127);
  - let is_overflow = fx.bcx.ins().bor(rhs_msb_gt_0, rhs_lsb_ge_128);*/
  - let is_overflow = fx.bcx.ins().bconst(types::B1, false);
  -
  - Some(fx.bcx.ins().bint(types::I8, is_overflow))
  - } else {
  - None
  - };
  -
  - let truncated_rhs = clif_intcast(fx, rhs_val, types::I32, false);
  - let val = match bin_op {
  - BinOp::Shl => fx.bcx.ins().ishl(lhs_val, truncated_rhs),
  - BinOp::Shr => {
  - if is_signed {
  - fx.bcx.ins().sshr(lhs_val, truncated_rhs)
  - } else {
  - fx.bcx.ins().ushr(lhs_val, truncated_rhs)
  - }
  - }
  - _ => unreachable!(),
  - };
  - if let Some(is_overflow) = is_overflow {
  - let out_ty = fx.tcx.mk_tup([lhs.layout().ty, fx.tcx.types.bool].iter());
  - Some(CValue::by_val_pair(val, is_overflow, fx.layout_of(out_ty)))
  - } else {
  - Some(CValue::by_val(val, lhs.layout()))
  - }
  - }
  + BinOp::Shl | BinOp::Shr => None,
  }
  }
  