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|
(module
(export "a8" (func $a8))
(table 2 2 funcref)
(elem (i32.const 0) $a9 $c8)
(func $a (param $x i32))
(func $b
(call $a (i32.const 1)) ;; best case scenario
)
(func $a1 (param $x i32)
(unreachable)
)
(func $b1
(call $a1 (i32.const 2)) ;; same value in both, so works
)
(func $b11
(call $a1 (i32.const 2))
)
(func $a2 (param $x i32)
(drop (local.get $x))
)
(func $b2
(call $a2 (i32.const 3)) ;; different value!
)
(func $b22
(call $a2 (i32.const 4))
)
(func $a3 (param $x i32)
(drop (i32.const -1)) ;; diff value, but at least unused, so no need to send
)
(func $b3
(call $a3 (i32.const 3))
)
(func $b33
(call $a3 (i32.const 4))
)
(func $a4 (param $x i32) ;; diff value, but with effects
)
(func $b4
(call $a4 (unreachable))
)
(func $b43
(call $a4 (i32.const 4))
)
(func $a5 (param $x i32) (param $y f64) ;; optimize two
(drop (local.get $x))
(drop (local.get $y))
)
(func $b5
(call $a5 (i32.const 1) (f64.const 3.14159))
)
(func $a6 (param $x i32) (param $y f64) ;; optimize just one
(drop (local.get $x))
(drop (local.get $y))
)
(func $b6
(call $a6 (unreachable) (f64.const 3.14159))
)
(func $a7 (param $x i32) (param $y f64) ;; optimize just the other one
(drop (local.get $x))
(drop (local.get $y))
)
(func $b7
(call $a7 (i32.const 1) (unreachable))
)
(func $a8 (param $x i32)) ;; exported, do not optimize
(func $b8
(call $a8 (i32.const 1))
)
(func $a9 (param $x i32)) ;; tabled, do not optimize
(func $b9
(call $a9 (i32.const 1))
)
(func $a10 (param $x i32) ;; recursion
(call $a10 (i32.const 1))
(call $a10 (i32.const 1))
)
(func $a11 (param $x i32) ;; partially successful recursion
(call $a11 (i32.const 1))
(call $a11 (i32.const 2))
)
(func $a12 (param $x i32) ;; unsuccessful recursion
(drop (local.get $x))
(call $a12 (i32.const 1))
(call $a12 (i32.const 2))
)
;; return values
(func $c1
(local $x i32)
(drop (call $c2))
(drop (call $c3))
(drop (call $c3))
(drop (call $c4))
(local.set $x (call $c4))
(drop (call $c5 (unreachable)))
(drop (call $c6))
(drop (call $c7))
(drop (call $c8))
)
(func $c2 (result i32)
(i32.const 1)
)
(func $c3 (result i32)
(i32.const 2)
)
(func $c4 (result i32)
(i32.const 3)
)
(func $c5 (param $x i32) (result i32)
(local.get $x)
)
(func $c6 (result i32)
(unreachable)
)
(func $c7 (result i32)
(return (i32.const 4))
)
(func $c8 (result i32)
(i32.const 5)
)
)
(module ;; both operations at once: remove params and return value
(func "a"
(drop
(call $b
(i32.const 1)
)
)
)
(func $b (param $x i32) (result i32)
(local.get $x)
)
)
(module ;; tail calls inhibit dropped result removal
(func $foo (param $x i32) (result i32)
(drop
(return_call $bar
(i32.const 0)
)
)
(i32.const 42)
)
(func $bar (param $x i32) (result i32)
(i32.const 7)
)
)
(module ;; indirect tail calls inhibit dropped result removal
(type $T (func (result i32)))
(table 1 1 funcref)
(func $foo (param $x i32) (result i32)
(drop
(return_call_indirect (type $T)
(i32.const 0)
)
)
)
(func $bar
(drop
(call $foo
(i32.const 42)
)
)
)
)
(module
(func $0 (param $0 funcref) (param $1 i32) (param $2 f64) (result i64)
(nop)
(unreachable)
)
(func "export" (param $0 f32) (result funcref)
;; a ref.func should prevent us from changing the type of a function, as it
;; may escape
(ref.func $0)
)
)
|
