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|
// |jit-test| skip-if: !wasmGcEnabled()
const preamble = `
(type $s1 (struct))
(type $s2 (sub $s1 (struct (field i32))))
(type $a1 (array (ref null $s1)))
(type $a2 (sub $a1 (array (ref null $s2))))
(type $f1 (func))
(func $f (type $f1))
(elem declare func $f) ;; allow $f to be ref.func'd
`;
// All the concrete subtype relationships present in the preamble.
// [x, y] means x <: y.
const subtypes = [
['$s2', '$s1'],
['$a2', '$a1'],
];
const typeSets = [
[
{ name: 'any' },
{ name: 'eq' },
{ name: 'struct' },
{ name: '$s1', make: 'struct.new_default $s1' },
{ name: '$s2', make: 'struct.new_default $s2' },
{ name: 'none', none: true },
],
[
{ name: 'any' },
{ name: 'eq' },
{ name: 'array' },
{ name: '$a1', make: '(array.new_default $a1 (i32.const 10))' },
{ name: '$a2', make: '(array.new_default $a2 (i32.const 10))' },
{ name: 'none', none: true },
],
[
{ name: 'any' },
{ name: 'eq' },
{ name: '$s1', make: 'struct.new_default $s1' },
{ name: '$s2', make: 'struct.new_default $s2' },
{ name: '$a1', make: '(array.new_default $a1 (i32.const 10))' },
{ name: '$a2', make: '(array.new_default $a2 (i32.const 10))' },
{ name: 'none', none: true },
],
// i31 eventually
// Apparently we don't support casting functions yet? That should be remedied...
// [
// { name: 'func' },
// { name: '$f1', make: 'ref.func $f' },
// { name: 'nofunc', none: true },
// ],
// TODO: extern
];
const nullables = [ // for example:
[true, true, true], // null $s1 -> null any -> null eq
[true, true, false], // null $s1 -> null any -> eq
[true, false, true], // null $s1 -> any -> null eq
[true, false, false], // null $s1 -> any -> eq
[false, true, true], // $s1 -> null any -> null eq
[false, true, false], // $s1 -> null any -> eq
[false, false, true], // $s1 -> any -> null eq
[false, false, false], // $s1 -> any -> eq
]
function isSubtype(src, dest) {
if (src.name === dest.name) {
return true;
}
for (const [src2, dest2] of subtypes) {
if (src.name === src2 && dest.name === dest2) {
return true;
}
}
return false;
}
let numCases = 0;
// Replace this with a string like 'non-null (ref $s1) -> (ref any) -> (ref any)' to test exactly one specific case. Makes debugging easier.
const specificTest = '';
// This will generate an enormous pile of test cases. All of these should be valid,
// as in passing WebAssembly.validate, but some may not be good casts at runtime.
for (const typeSet of typeSets) {
for (const start of typeSet) {
for (const middle of typeSet) {
for (const end of typeSet) {
for (const [nullable0, nullable1, nullable2] of nullables) {
for (const makeNull of [true, false]) {
const concrete0 = !!start.make;
const concrete1 = !!middle.make;
const concrete2 = !!end.make;
if (!concrete0 && !makeNull) {
// We can only start with null values for abstract types
continue;
}
if (!nullable0 && makeNull) {
// Can't use null as a valid value for a non-nullable type
continue;
}
numCases += 1;
let good1 = true;
let good2 = true;
// Null values will fail casts to non-nullable types
if (makeNull) {
if (!nullable1) {
good1 = false;
}
if (!nullable2) {
good2 = false;
}
}
// Bottom types can't represent non-null, so this will always fail
if (!makeNull) {
if (middle.none) {
good1 = false;
}
if (end.none) {
good2 = false;
}
}
// Concrete values are subject to subtyping relationships
if (!makeNull) {
if (concrete1 && !isSubtype(start, middle)) {
good1 = false;
}
if (concrete2 && !isSubtype(start, end)) {
good2 = false;
}
}
let emoji1 = good1 ? '✅' : '❌';
let emoji2 = good2 ? '✅' : '❌';
if (!good1) {
good2 = false;
emoji2 = '❓';
}
const name = `${makeNull ? 'null' : 'non-null'} (ref ${nullable0 ? 'null ' : ''}${start.name}) -> (ref ${nullable1 ? 'null ' : ''}${middle.name}) -> (ref ${nullable2 ? 'null ' : ''}${end.name})`;
if (specificTest && name != specificTest) {
continue;
}
print(`${emoji1}${emoji2} ${name}`);
const make = makeNull ? `ref.null ${start.name}` : start.make;
const type1 = `(ref ${nullable1 ? 'null ' : ''}${middle.name})`;
const type2 = `(ref ${nullable2 ? 'null ' : ''}${end.name})`;
const moduleText = `(module
${preamble}
(func (export "cast1") (result ${type1})
${make}
ref.cast ${type1}
)
(func (export "cast2") (param ${type1}) (result ${type2})
local.get 0
ref.cast ${type2}
)
(func (export "test1") (result i32)
${make}
ref.test ${type1}
)
(func (export "test2") (param ${type1}) (result i32)
local.get 0
ref.test ${type2}
)
;; these are basically ref.test but with branches
(func (export "branch1") (result i32)
(block (result ${type1})
${make}
br_on_cast 0 anyref ${type1}
drop
(return (i32.const 0))
)
drop
(return (i32.const 1))
)
(func (export "branch2") (param ${type1}) (result i32)
(block (result ${type2})
local.get 0
br_on_cast 0 anyref ${type2}
drop
(return (i32.const 0))
)
drop
(return (i32.const 1))
)
(func (export "branchfail1") (result i32)
(block (result anyref)
${make}
br_on_cast_fail 0 anyref ${type1}
drop
(return (i32.const 1))
)
drop
(return (i32.const 0))
)
(func (export "branchfail2") (param ${type1}) (result i32)
(block (result anyref)
local.get 0
br_on_cast_fail 0 anyref ${type2}
drop
(return (i32.const 1))
)
drop
(return (i32.const 0))
)
)`;
try {
// The casts are split up so the stack trace will show you which cast is failing.
const {
cast1, cast2,
test1, test2,
branch1, branch2,
branchfail1, branchfail2,
} = wasmEvalText(moduleText).exports;
function assertCast(func, good) {
if (good) {
return [func(), true];
} else {
assertErrorMessage(func, WebAssembly.RuntimeError, /bad cast/);
return [null, false];
}
}
const [res1, ok1] = assertCast(cast1, good1);
assertEq(test1(), good1 ? 1 : 0);
assertEq(branch1(), good1 ? 1 : 0);
assertEq(branchfail1(), good1 ? 1 : 0);
if (ok1) {
assertCast(() => cast2(res1), good2);
assertEq(test2(res1), good2 ? 1 : 0);
assertEq(branch2(res1), good2 ? 1 : 0);
assertEq(branchfail2(res1), good2 ? 1 : 0);
}
} catch (e) {
print("Failed! Module text was:");
print(moduleText);
throw e;
}
}
}
}
}
}
}
print(`we hope you have enjoyed these ${numCases} test cases 😁`);
|
