test/lit/passes/local-subtyping-desc.wast

;; NOTE: Assertions have been generated by update_lit_checks.py and should not be edited.

;; RUN: wasm-opt %s -all --local-subtyping -S -o - | filecheck %s

(module
 (rec
  ;; CHECK:      (rec
  ;; CHECK-NEXT:  (type $struct (sub (descriptor $desc) (struct)))
  (type $struct (sub  (descriptor $desc) (struct)))
  ;; CHECK:       (type $desc (sub (describes $struct) (struct (field i32))))
  (type $desc (sub  (describes $struct) (struct (field i32))))
 )

 ;; CHECK:      (func $test (type $2) (result (ref null $struct))
 ;; CHECK-NEXT:  (local $struct (ref none))
 ;; CHECK-NEXT:  (block $block (result (ref none))
 ;; CHECK-NEXT:   (local.set $struct
 ;; CHECK-NEXT:    (block ;; (replaces unreachable BrOn we can't emit)
 ;; CHECK-NEXT:     (drop
 ;; CHECK-NEXT:      (ref.null none)
 ;; CHECK-NEXT:     )
 ;; CHECK-NEXT:     (drop
 ;; CHECK-NEXT:      (block (result (ref none))
 ;; CHECK-NEXT:       (ref.as_non_null
 ;; CHECK-NEXT:        (ref.null none)
 ;; CHECK-NEXT:       )
 ;; CHECK-NEXT:      )
 ;; CHECK-NEXT:     )
 ;; CHECK-NEXT:     (unreachable)
 ;; CHECK-NEXT:    )
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:   (unreachable)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 (func $test (result (ref null $struct))
  ;; We can refine the local to (ref none). While doing so we must
  ;; refinalize the br_on properly, below, to that same type (it is never
  ;; executed). In more detail:
  ;;
  ;;  * Initially, after parsing, the types of its inputs are
  ;;      ref=nullref, desc=(ref $desc).
  ;;    That refinalizes into (ref none) for the BrOn.
  ;;
  ;;  * When we refinalize, the types of its inputs are
  ;;      ref=nullref, desc=(ref none).
  ;;    This test verifies that we fixed a bug where the BrOn was given the
  ;;    type of the ref, i.e., nullref - which led to an assert, as we refined
  ;;    (ref $struct) into nullref. That is, the code path handling a null
  ;;    descriptor type did not consider that it might need to emit a non-
  ;;    nullable type even if the ref is nullable.
  ;;
  (local $struct (ref $struct))
  (block $block (result (ref null $struct))
   (local.set $struct
    (br_on_cast_desc_eq $block (ref null $struct) (ref null $struct)
     (ref.null $struct)
     (block (result (ref $desc))
      (ref.as_non_null
       (ref.null none)
      )
     )
    )
   )
   (unreachable)
  )
 )
)