+ let discr = codegen_operand(fx, discr).load_scalar(fx);
+
+ let use_bool_opt = switch_ty.kind() == fx.tcx.types.bool.kind()
+ || (targets.iter().count() == 1 && targets.iter().next().unwrap().0 == 0);
+ if use_bool_opt {
+ assert_eq!(targets.iter().count(), 1);
+ let (then_value, then_block) = targets.iter().next().unwrap();
+ let then_block = fx.get_block(then_block);
+ let else_block = fx.get_block(targets.otherwise());
+ let test_zero = match then_value {
+ 0 => true,
+ 1 => false,
+ _ => unreachable!("{:?}", targets),
+ };
+
+ let discr = crate::optimize::peephole::maybe_unwrap_bint(&mut fx.bcx, discr);
+ let (discr, is_inverted) =
+ crate::optimize::peephole::maybe_unwrap_bool_not(&mut fx.bcx, discr);
+ let test_zero = if is_inverted { !test_zero } else { test_zero };
+ let discr = crate::optimize::peephole::maybe_unwrap_bint(&mut fx.bcx, discr);
+ let discr =
+ crate::optimize::peephole::make_branchable_value(&mut fx.bcx, discr);
+ if let Some(taken) = crate::optimize::peephole::maybe_known_branch_taken(
+ &fx.bcx, discr, test_zero,
+ ) {
+ if taken {
+ fx.bcx.ins().jump(then_block, &[]);
+ } else {
+ fx.bcx.ins().jump(else_block, &[]);
+ }
+ } else {
+ if test_zero {
+ fx.bcx.ins().brz(discr, then_block, &[]);
+ fx.bcx.ins().jump(else_block, &[]);
+ } else {
+ fx.bcx.ins().brnz(discr, then_block, &[]);
+ fx.bcx.ins().jump(else_block, &[]);
+ }
+ }
+ } else {
+ let mut switch = ::cranelift_frontend::Switch::new();
+ for (value, block) in targets.iter() {
+ let block = fx.get_block(block);
+ switch.set_entry(value, block);
+ }
+ let otherwise_block = fx.get_block(targets.otherwise());
+ switch.emit(&mut fx.bcx, discr, otherwise_block);