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// |jit-test| skip-if: !wasmGcEnabled()
let InvalidI31Values = [
null,
Number.EPSILON,
Number.MAX_SAFE_INTEGER,
Number.MIN_SAFE_INTEGER,
Number.MIN_VALUE,
Number.MAX_VALUE,
Number.NaN,
-0,
// Number objects are not coerced
...WasmI31refValues.map(n => new Number(n)),
// Non-integers are not valid
...WasmI31refValues.map(n => n + 0.1),
...WasmI31refValues.map(n => n + 0.5),
...WasmI31refValues.map(n => n + 0.9)
];
// Return an equivalent JS number for if a JS number is converted to i31ref
// and then zero extended back to 32-bits.
function valueAsI31GetU(value) {
// Zero extending will drop the sign bit, if any
return value & 0x7fffffff;
}
let identity = (n) => n;
let {
castFromAnyref,
castFromExternref,
refI31,
refI31Identity,
i31GetU,
i31GetS,
i31EqualsI31,
i31EqualsEq
} = wasmEvalText(`(module
(func $identity (import "" "identity") (param anyref) (result anyref))
(func (export "castFromAnyref") (param anyref) (result i32)
local.get 0
ref.test (ref i31)
)
(func (export "castFromExternref") (param externref) (result i32)
local.get 0
any.convert_extern
ref.test (ref i31)
)
(func (export "refI31") (param i32) (result anyref)
local.get 0
ref.i31
)
(func (export "refI31Identity") (param i32) (result anyref)
local.get 0
ref.i31
call $identity
)
(func (export "i31GetU") (param i32) (result i32)
local.get 0
ref.i31
i31.get_u
)
(func (export "i31GetS") (param i32) (result i32)
local.get 0
ref.i31
i31.get_s
)
(func (export "i31EqualsI31") (param i32) (param i32) (result i32)
(ref.eq
(ref.i31 local.get 0)
(ref.i31 local.get 1)
)
)
(func (export "i31EqualsEq") (param i32) (param eqref) (result i32)
(ref.eq
(ref.i31 local.get 0)
local.get 1
)
)
)`, {"": {identity}}).exports;
// Test that wasm will represent JS number values that are 31-bit integers as
// an i31ref
for (let i of WasmI31refValues) {
assertEq(castFromAnyref(i), 1);
assertEq(castFromExternref(i), 1);
}
// Test that wasm will not represent a JS value that is not a 31-bit number as
// an i31ref
for (let i of InvalidI31Values) {
assertEq(castFromAnyref(i), 0);
assertEq(castFromExternref(i), 0);
}
// Test that we can roundtrip 31-bit integers through the i31ref type
// faithfully.
for (let i of WasmI31refValues) {
assertEq(refI31(i), i);
assertEq(refI31Identity(i), i);
assertEq(i31GetU(i), valueAsI31GetU(i));
assertEq(i31GetS(i), i);
}
// Test that i31ref values are truncated when given a 32-bit value
for (let i of WasmI31refValues) {
let adjusted = i | 0x80000000;
assertEq(refI31(adjusted), i);
}
// Test that comparing identical i31 values works
for (let a of WasmI31refValues) {
for (let b of WasmI31refValues) {
assertEq(!!i31EqualsI31(a, b), a === b);
}
}
// Test that an i31ref is never mistaken for a different kind of reference
for (let a of WasmI31refValues) {
for (let b of WasmEqrefValues) {
assertEq(!!i31EqualsEq(a, b), a === b);
}
}
// Test that i32 values get wrapped correctly
const bigI32Tests = [
{
input: MaxI31refValue + 1,
expected: MinI31refValue,
},
{
input: MinI31refValue - 1,
expected: MaxI31refValue,
},
]
for (const {input, expected} of bigI32Tests) {
const { get, getElem } = wasmEvalText(`(module
(func (export "get") (param i32) (result i32)
(i31.get_s (ref.i31 (local.get 0)))
)
(table i31ref (elem (item (ref.i31 (i32.const ${input})))))
(func (export "getElem") (result i32)
(i31.get_s (table.get 0 (i32.const 0)))
)
)`).exports;
assertEq(get(input), expected);
assertEq(getElem(), expected);
}
const { i31GetU_null, i31GetS_null } = wasmEvalText(`(module
(func (export "i31GetU_null") (result i32)
ref.null i31
i31.get_u
)
(func (export "i31GetS_null") (result i32)
ref.null i31
i31.get_s
)
)`).exports;
assertErrorMessage(() => i31GetU_null(), WebAssembly.RuntimeError, /dereferencing null pointer/);
assertErrorMessage(() => i31GetS_null(), WebAssembly.RuntimeError, /dereferencing null pointer/);
|
