test/lit/passes/dce-gc.wast

;; NOTE: Assertions have been generated by update_lit_checks.py and should not be edited.
;; RUN: wasm-opt %s --dce -all -S -o - | filecheck %s

(module
  ;; CHECK:      (func $param1 (param $ignore nullfuncref) (param $no (ref nofunc))
  ;; CHECK-NEXT:  (drop
  ;; CHECK-NEXT:   (local.get $ignore)
  ;; CHECK-NEXT:  )
  ;; CHECK-NEXT:  (block
  ;; CHECK-NEXT:   (drop
  ;; CHECK-NEXT:    (local.get $no)
  ;; CHECK-NEXT:   )
  ;; CHECK-NEXT:   (unreachable)
  ;; CHECK-NEXT:  )
  ;; CHECK-NEXT: )
  (func $param1 (param $ignore (ref null nofunc)) (param $no (ref nofunc))
    ;; The first param may be a null, and we ignore it. The second can be
    ;; optimized by putting an unreachable after it.
    (drop
      (local.get $ignore)
    )
    (drop
      (local.get $no)
    )
  )

  ;; CHECK:      (func $param2 (param $no (ref noextern))
  ;; CHECK-NEXT:  (drop
  ;; CHECK-NEXT:   (local.get $no)
  ;; CHECK-NEXT:  )
  ;; CHECK-NEXT:  (unreachable)
  ;; CHECK-NEXT: )
  (func $param2 (param $no (ref noextern))
    (drop
      (local.get $no)
    )
  )

  ;; CHECK:      (func $param3 (param $no (ref none))
  ;; CHECK-NEXT:  (drop
  ;; CHECK-NEXT:   (local.get $no)
  ;; CHECK-NEXT:  )
  ;; CHECK-NEXT:  (unreachable)
  ;; CHECK-NEXT: )
  (func $param3 (param $no (ref none))
    (drop
      (local.get $no)
    )
  )

  ;; CHECK:      (func $return (result (ref nofunc))
  ;; CHECK-NEXT:  (unreachable)
  ;; CHECK-NEXT: )
  (func $return (result (ref nofunc))
    (unreachable)
  )

  ;; CHECK:      (func $call
  ;; CHECK-NEXT:  (drop
  ;; CHECK-NEXT:   (call $return)
  ;; CHECK-NEXT:  )
  ;; CHECK-NEXT:  (unreachable)
  ;; CHECK-NEXT: )
  (func $call
    (drop
      (call $return)
    )
  )

  ;; CHECK:      (func $type-updating
  ;; CHECK-NEXT:  (block $block
  ;; CHECK-NEXT:   (block
  ;; CHECK-NEXT:    (drop
  ;; CHECK-NEXT:     (br_on_null $block
  ;; CHECK-NEXT:      (ref.null none)
  ;; CHECK-NEXT:     )
  ;; CHECK-NEXT:    )
  ;; CHECK-NEXT:    (unreachable)
  ;; CHECK-NEXT:   )
  ;; CHECK-NEXT:  )
  ;; CHECK-NEXT: )
  (func $type-updating
    (block $block
      (drop
        ;; The value flowing out of this br is a non-nullable null, so it is
        ;; unreachable. While optimizing it we must properly update the types
        ;; above us to propagate the new unreachability, but while doing so we
        ;; must not make the mistake of changing the block's type, as it remains
        ;; reachable (due to the branch to it).
        (br_on_null $block
          (ref.null none)
        )
      )
      ;; Do a return to avoid the block's type being reachable just due to the
      ;; fallthrough. (This return will be removed since it is after the
      ;; unreachable we'll emit after the drop.)
      (return)
    )
  )
)