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// Test that array.fill correctly pre-barriers reference-typed elements.
const {
makeRefArray,
fillNull,
fillValue,
makeStruct,
getElement,
} = wasmEvalText(`(module
(type $S (struct (field i32)))
(type $A (array (mut anyref)))
(func (export "makeStruct") (result anyref)
(struct.new $S (i32.const 42))
)
(func (export "makeRefArray") (param i32) (result anyref)
(array.new $A (ref.null any) (local.get 0))
)
(func (export "getElement") (param anyref) (param i32) (result anyref)
(array.get $A (ref.cast (ref $A) (local.get 0)) (local.get 1))
)
(func (export "fillNull") (param anyref) (param i32)
(array.fill $A
(ref.cast (ref $A) (local.get 0))
(i32.const 0)
(ref.null any)
(local.get 1))
)
(func (export "fillValue") (param anyref) (param i32) (param anyref)
(array.fill $A
(ref.cast (ref $A) (local.get 0))
(i32.const 0)
(local.get 2)
(local.get 1))
)
)`).exports;
const len = 16;
let arr = makeRefArray(len);
let s = makeStruct();
// Fill array with struct references
fillValue(arr, len, s);
assertEq(getElement(arr, 0), s);
// Overwriting non-null refs with null must pre-barrier the old values.
// verifyprebarriers() snapshots all edges, then on the second call checks
// that any removed edge was properly barriered.
verifyprebarriers();
fillNull(arr, len);
verifyprebarriers();
assertEq(getElement(arr, 0), null);
// Also test overwriting null refs with non-null (pre-barrier on null is a
// no-op, but the code path should still be exercised).
verifyprebarriers();
fillValue(arr, len, s);
verifyprebarriers();
assertEq(getElement(arr, 0), s);
// And overwriting non-null with a different non-null value.
let s2 = makeStruct();
verifyprebarriers();
fillValue(arr, len, s2);
verifyprebarriers();
assertEq(getElement(arr, 0), s2);