test/lit/passes/coalesce-locals-gc.wast

;; NOTE: Assertions have been generated by update_lit_checks.py and should not be edited.
;; RUN: wasm-opt %s --remove-unused-names --coalesce-locals -all -S -o - \
;; RUN:   | filecheck %s

;; --remove-unused-names is run to avoid adding names to blocks. Block names
;; can prevent non-nullable local validation (we emit named blocks in the binary
;; format, if we need them, but never emit unnamed ones), which affects some
;; testcases.

(module
 ;; CHECK:      (type $array (array (mut i8)))
 (type $array (array (mut i8)))
 ;; CHECK:      (global $global (ref null $array) (ref.null $array))
 (global $global (ref null $array) (ref.null $array))

 ;; CHECK:      (func $test-dead-get-non-nullable (param $0 (ref data))
 ;; CHECK-NEXT:  (unreachable)
 ;; CHECK-NEXT:  (drop
 ;; CHECK-NEXT:   (block (result (ref data))
 ;; CHECK-NEXT:    (unreachable)
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 (func $test-dead-get-non-nullable (param $func (ref data))
  (unreachable)
  (drop
   ;; A useless get (that does not read from any set, or from the inputs to the
   ;; function). Normally we replace such gets with nops as best we can, but in
   ;; this case the type is non-nullable, so we must leave it alone.
   (local.get $func)
  )
 )

 ;; CHECK:      (func $br_on_null (param $0 (ref null $array)) (result (ref null $array))
 ;; CHECK-NEXT:  (block $label$1 (result (ref null $array))
 ;; CHECK-NEXT:   (block $label$2
 ;; CHECK-NEXT:    (br $label$1
 ;; CHECK-NEXT:     (br_on_null $label$2
 ;; CHECK-NEXT:      (local.get $0)
 ;; CHECK-NEXT:     )
 ;; CHECK-NEXT:    )
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:   (local.set $0
 ;; CHECK-NEXT:    (global.get $global)
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:   (local.get $0)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 (func $br_on_null (param $ref (ref null $array)) (result (ref null $array))
  (local $1 (ref null $array))
  (block $label$1 (result (ref null $array))
   (block $label$2
    (br $label$1
     ;; Test that we properly model the basic block connections around a
     ;; BrOnNull. There should be a branch to $label$2, and also a fallthrough.
     ;; As a result, the local.set below is reachable, and should not be
     ;; eliminated (turned into a drop).
     (br_on_null $label$2
      (local.get $ref)
     )
    )
   )
   (local.set $1
    (global.get $global)
   )
   (local.get $1)
  )
 )

 ;; CHECK:      (func $nn-dead
 ;; CHECK-NEXT:  (local $0 funcref)
 ;; CHECK-NEXT:  (drop
 ;; CHECK-NEXT:   (ref.func $nn-dead)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT:  (block $inner
 ;; CHECK-NEXT:   (local.set $0
 ;; CHECK-NEXT:    (ref.func $nn-dead)
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:   (br_if $inner
 ;; CHECK-NEXT:    (i32.const 1)
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT:  (drop
 ;; CHECK-NEXT:   (ref.as_non_null
 ;; CHECK-NEXT:    (local.get $0)
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 (func $nn-dead
  (local $x (ref func))
  (local.set $x
   (ref.func $nn-dead) ;; this will be removed, as it is not needed.
  )
  (block $inner
   (local.set $x
    (ref.func $nn-dead) ;; this is not enough for validation of the get, so we
                        ;; will end up making the local nullable.
   )
   ;; refer to $inner to keep the name alive (see the next testcase)
   (br_if $inner
    (i32.const 1)
   )
  )
  (drop
   (local.get $x)
  )
 )

 ;; CHECK:      (func $nn-dead-nameless
 ;; CHECK-NEXT:  (local $0 (ref func))
 ;; CHECK-NEXT:  (drop
 ;; CHECK-NEXT:   (ref.func $nn-dead)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT:  (block
 ;; CHECK-NEXT:   (local.set $0
 ;; CHECK-NEXT:    (ref.func $nn-dead)
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT:  (drop
 ;; CHECK-NEXT:   (local.get $0)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 (func $nn-dead-nameless
  (local $x (ref func))
  (local.set $x
   (ref.func $nn-dead)
  )
  ;; As above, but now the block has no name. Nameless blocks do not interfere
  ;; with validation, so we can keep the local non-nullable.
  (block
   (local.set $x
    (ref.func $nn-dead)
   )
  )
  (drop
   (local.get $x)
  )
 )
)