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;; NOTE: Assertions have been generated by update_lit_checks.py and should not be edited.
;; Run in both TNH and non-TNH mode.
;; RUN: wasm-opt %s --vacuum --traps-never-happen -all -S -o - | filecheck %s --check-prefix=YESTNH
;; RUN: wasm-opt %s --vacuum -all -S -o - | filecheck %s --check-prefix=NO_TNH
(module
(memory 1 1)
;; YESTNH: (type $struct (struct (field (mut i32))))
;; NO_TNH: (type $struct (struct (field (mut i32))))
(type $struct (struct (field (mut i32))))
;; YESTNH: (func $drop (type $i32_anyref_=>_none) (param $x i32) (param $y anyref)
;; YESTNH-NEXT: (nop)
;; YESTNH-NEXT: )
;; NO_TNH: (func $drop (type $i32_anyref_=>_none) (param $x i32) (param $y anyref)
;; NO_TNH-NEXT: (drop
;; NO_TNH-NEXT: (i32.load
;; NO_TNH-NEXT: (local.get $x)
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: (drop
;; NO_TNH-NEXT: (ref.as_non_null
;; NO_TNH-NEXT: (local.get $y)
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: (drop
;; NO_TNH-NEXT: (ref.as_i31
;; NO_TNH-NEXT: (local.get $y)
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: (drop
;; NO_TNH-NEXT: (unreachable)
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: )
(func $drop (param $x i32) (param $y anyref)
;; A load might trap, normally, but if traps never happen then we can
;; remove it.
(drop
(i32.load (local.get $x))
)
;; A trap on a null value can also be ignored.
(drop
(ref.as_non_null
(local.get $y)
)
)
;; Other ref.as* as well.
(drop
(ref.as_i31
(local.get $y)
)
)
;; Ignore unreachable code.
(drop
(unreachable)
)
)
;; Other side effects prevent us making any changes.
;; YESTNH: (func $other-side-effects (type $i32_=>_i32) (param $x i32) (result i32)
;; YESTNH-NEXT: (drop
;; YESTNH-NEXT: (call $other-side-effects
;; YESTNH-NEXT: (i32.const 1)
;; YESTNH-NEXT: )
;; YESTNH-NEXT: )
;; YESTNH-NEXT: (local.set $x
;; YESTNH-NEXT: (i32.const 2)
;; YESTNH-NEXT: )
;; YESTNH-NEXT: (i32.const 1)
;; YESTNH-NEXT: )
;; NO_TNH: (func $other-side-effects (type $i32_=>_i32) (param $x i32) (result i32)
;; NO_TNH-NEXT: (drop
;; NO_TNH-NEXT: (call $other-side-effects
;; NO_TNH-NEXT: (i32.const 1)
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: (drop
;; NO_TNH-NEXT: (block (result i32)
;; NO_TNH-NEXT: (local.set $x
;; NO_TNH-NEXT: (i32.const 2)
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: (i32.load
;; NO_TNH-NEXT: (local.get $x)
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: (i32.const 1)
;; NO_TNH-NEXT: )
(func $other-side-effects (param $x i32) (result i32)
;; A call has all manner of other side effects.
(drop
(call $other-side-effects (i32.const 1))
)
;; Add to the load an additional specific side effect, of writing to a
;; local. We can remove the load, but not the write to a local.
(drop
(block (result i32)
(local.set $x (i32.const 2))
(i32.load (local.get $x))
)
)
(i32.const 1)
)
;; A helper function for the above, that returns nothing.
;; YESTNH: (func $return-nothing (type $none_=>_none)
;; YESTNH-NEXT: (nop)
;; YESTNH-NEXT: )
;; NO_TNH: (func $return-nothing (type $none_=>_none)
;; NO_TNH-NEXT: (nop)
;; NO_TNH-NEXT: )
(func $return-nothing)
;; YESTNH: (func $partial (type $ref|$struct|_=>_ref?|$struct|) (param $x (ref $struct)) (result (ref null $struct))
;; YESTNH-NEXT: (local $y (ref null $struct))
;; YESTNH-NEXT: (local.set $y
;; YESTNH-NEXT: (local.get $x)
;; YESTNH-NEXT: )
;; YESTNH-NEXT: (local.set $y
;; YESTNH-NEXT: (local.get $x)
;; YESTNH-NEXT: )
;; YESTNH-NEXT: (local.get $y)
;; YESTNH-NEXT: )
;; NO_TNH: (func $partial (type $ref|$struct|_=>_ref?|$struct|) (param $x (ref $struct)) (result (ref null $struct))
;; NO_TNH-NEXT: (local $y (ref null $struct))
;; NO_TNH-NEXT: (drop
;; NO_TNH-NEXT: (struct.get $struct 0
;; NO_TNH-NEXT: (local.tee $y
;; NO_TNH-NEXT: (local.get $x)
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: (drop
;; NO_TNH-NEXT: (struct.get $struct 0
;; NO_TNH-NEXT: (local.tee $y
;; NO_TNH-NEXT: (local.get $x)
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: (local.get $y)
;; NO_TNH-NEXT: )
(func $partial (param $x (ref $struct)) (result (ref null $struct))
(local $y (ref null $struct))
;; The struct.get's side effect can be ignored due to tnh, and the value is
;; dropped anyhow, so we can remove it. We cannot remove the local.tee
;; inside it, however, so we must only vacuum out the struct.get and
;; nothing more. (In addition, a drop of a tee will become a set.)
(drop
(struct.get $struct 0
(local.tee $y
(local.get $x)
)
)
)
;; Similar, but with an eqz on the outside, which can also be removed.
(drop
(i32.eqz
(struct.get $struct 0
(local.tee $y
(local.get $x)
)
)
)
)
(local.get $y)
)
;; YESTNH: (func $toplevel (type $none_=>_none)
;; YESTNH-NEXT: (nop)
;; YESTNH-NEXT: )
;; NO_TNH: (func $toplevel (type $none_=>_none)
;; NO_TNH-NEXT: (unreachable)
;; NO_TNH-NEXT: )
(func $toplevel
;; A removable side effect at the top level of a function. We can turn this
;; into a nop.
(unreachable)
)
;; YESTNH: (func $drop-loop (type $none_=>_none)
;; YESTNH-NEXT: (drop
;; YESTNH-NEXT: (loop $loop (result i32)
;; YESTNH-NEXT: (br_if $loop
;; YESTNH-NEXT: (i32.const 1)
;; YESTNH-NEXT: )
;; YESTNH-NEXT: (i32.const 10)
;; YESTNH-NEXT: )
;; YESTNH-NEXT: )
;; YESTNH-NEXT: )
;; NO_TNH: (func $drop-loop (type $none_=>_none)
;; NO_TNH-NEXT: (drop
;; NO_TNH-NEXT: (loop $loop (result i32)
;; NO_TNH-NEXT: (br_if $loop
;; NO_TNH-NEXT: (i32.const 1)
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: (i32.const 10)
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: )
(func $drop-loop
;; A loop has the effect of potentially being infinite. Even in TNH mode we
;; do not optimize out such loops.
(drop
(loop $loop (result i32)
(br_if $loop
(i32.const 1)
)
(i32.const 10)
)
)
)
;; YESTNH: (func $loop-effects (type $none_=>_none)
;; YESTNH-NEXT: (drop
;; YESTNH-NEXT: (loop $loop (result i32)
;; YESTNH-NEXT: (drop
;; YESTNH-NEXT: (i32.atomic.load
;; YESTNH-NEXT: (i32.const 0)
;; YESTNH-NEXT: )
;; YESTNH-NEXT: )
;; YESTNH-NEXT: (br_if $loop
;; YESTNH-NEXT: (i32.const 1)
;; YESTNH-NEXT: )
;; YESTNH-NEXT: (i32.const 10)
;; YESTNH-NEXT: )
;; YESTNH-NEXT: )
;; YESTNH-NEXT: )
;; NO_TNH: (func $loop-effects (type $none_=>_none)
;; NO_TNH-NEXT: (drop
;; NO_TNH-NEXT: (loop $loop (result i32)
;; NO_TNH-NEXT: (drop
;; NO_TNH-NEXT: (i32.atomic.load
;; NO_TNH-NEXT: (i32.const 0)
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: (br_if $loop
;; NO_TNH-NEXT: (i32.const 1)
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: (i32.const 10)
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: )
;; NO_TNH-NEXT: )
(func $loop-effects
;; As above, but the loop also has an atomic load effect. That prevents
;; optimization.
(drop
(loop $loop (result i32)
(drop
(i32.atomic.load
(i32.const 0)
)
)
(br_if $loop
(i32.const 1)
)
(i32.const 10)
)
)
)
)
|
