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|
// |jit-test| skip-if: !wasmGcEnabled()
// For the time being, we do not want to expose struct types outside of the
// module where they are defined, and so there are restrictions on how functions
// and global variables that traffic in struct types can be used.
//
// At the same time, intra-module uses of functions and globals that use struct
// types must be allowed to the greatest extent possible.
//
// Terminology: A function that takes a Ref parameter or returns a Ref result is
// "exposed for Ref", as is a global of Ref type. EqRef is OK though, in all
// cases.
//
// To keep it simple we have the following restrictions that can all be checked
// statically.
//
// - Exported and imported functions cannot be exposed for Ref.
//
// - If the module has an exported or imported table then no function stored in
// that table by the module (by means of an element segment) can be exposed
// for Ref.
//
// - If the module has an exported or imported table then no call_indirect via
// that table may reference a type that is exposed for Ref.
//
// - An exported or imported global cannot be exposed for Ref.
//
// Conversely,
//
// - If a module has a private table then it can contain private functions that
// are exposed for Ref and it is possible to call those functions via that
// table.
//
// - If a module has a private global then it can be exposed for ref.
//
// Note that
//
// - code generators can work around the restrictions by instead using
// functions and globals that use eqref, and by using downcasts to check
// that the types are indeed correct. (Though the meaning of downcast will
// change as the GC feature evolves.)
//
// - we could probably make the restrictions slightly softer but there's really
// no advantage to doing so.
function wasmCompile(text) {
return new WebAssembly.Module(wasmTextToBinary(text));
}
// Exported function can't take ref type parameter, but eqref is OK.
assertErrorMessage(() => wasmCompile(
`(module
(type $box (struct (field $x i32)))
(func (export "f") (param (ref null $box)) (unreachable)))`),
WebAssembly.CompileError,
/cannot expose indexed reference type/);
assertEq(typeof wasmCompile(
`(module
(func (export "f") (param eqref) (unreachable)))`),
"object");
// Exported function can't return ref result, but eqref is OK.
assertErrorMessage(() => wasmCompile(
`(module
(type $box (struct (field $x i32)))
(func (export "f") (result (ref null $box)) (ref.null $box)))`),
WebAssembly.CompileError,
/cannot expose indexed reference type/);
assertEq(typeof wasmCompile(
`(module
(func (export "f") (result eqref) (ref.null eq)))`),
"object");
// Imported function can't take ref parameter, but eqref is OK.
assertErrorMessage(() => wasmCompile(
`(module
(type $box (struct (field $x i32)))
(import "m" "f" (func (param (ref null $box)))))`),
WebAssembly.CompileError,
/cannot expose indexed reference type/);
assertEq(typeof wasmCompile(
`(module
(import "m" "f" (func (param eqref))))`),
"object");
// Imported function can't return ref type, but eqref is OK.
assertErrorMessage(() => wasmCompile(
`(module
(type $box (struct (field $x i32)))
(import "m" "f" (func (param i32) (result (ref null $box)))))`),
WebAssembly.CompileError,
/cannot expose indexed reference type/);
assertEq(typeof wasmCompile(
`(module
(import "m" "f" (func (param i32) (result eqref))))`),
"object");
// Imported global can't be of Ref type (irrespective of mutability), though eqref is OK.
assertErrorMessage(() => wasmCompile(
`(module
(type $box (struct (field $val i32)))
(import "m" "g" (global (mut (ref null $box)))))`),
WebAssembly.CompileError,
/cannot expose indexed reference type/);
assertErrorMessage(() => wasmCompile(
`(module
(type $box (struct (field $val i32)))
(import "m" "g" (global (ref null $box))))`),
WebAssembly.CompileError,
/cannot expose indexed reference type/);
assertEq(typeof wasmCompile(
`(module
(import "m" "g" (global (mut eqref))))`),
"object");
assertEq(typeof wasmCompile(
`(module
(import "m" "g" (global eqref)))`),
"object");
// Exported global can't be of Ref type (irrespective of mutability), though eqref is OK.
assertErrorMessage(() => wasmCompile(
`(module
(type $box (struct (field $val i32)))
(global $boxg (export "box") (mut (ref null $box)) (ref.null $box)))`),
WebAssembly.CompileError,
/cannot expose indexed reference type/);
assertErrorMessage(() => wasmCompile(
`(module
(type $box (struct (field $val i32)))
(global $boxg (export "box") (ref null $box) (ref.null $box)))`),
WebAssembly.CompileError,
/cannot expose indexed reference type/);
assertEq(typeof wasmCompile(
`(module
(global $boxg (export "box") (mut eqref) (ref.null eq)))`),
"object");
assertEq(typeof wasmCompile(
`(module
(global $boxg (export "box") eqref (ref.null eq)))`),
"object");
// Exported table cannot reference functions that are exposed for Ref, but eqref is OK.
assertErrorMessage(() => wasmCompile(
`(module
(type $box (struct (field $val i32)))
(table (export "tbl") 1 funcref)
(elem (i32.const 0) $f1)
(func $f1 (param (ref null $box)) (unreachable)))`),
WebAssembly.CompileError,
/cannot expose indexed reference type/);
assertErrorMessage(() => wasmCompile(
`(module
(type $box (struct (field $val i32)))
(table (export "tbl") 1 funcref)
(elem (i32.const 0) $f1)
(func $f1 (result (ref null $box)) (ref.null $box)))`),
WebAssembly.CompileError,
/cannot expose indexed reference type/);
assertEq(typeof wasmCompile(
`(module
(table (export "tbl") 1 funcref)
(elem (i32.const 0) $f1)
(func $f1 (param eqref) (unreachable)))`),
"object");
assertEq(typeof wasmCompile(
`(module
(table (export "tbl") 1 funcref)
(elem (i32.const 0) $f1)
(func $f1 (result eqref) (ref.null eq)))`),
"object");
// Imported table cannot reference functions that are exposed for Ref, though eqref is OK.
assertErrorMessage(() => wasmCompile(
`(module
(type $box (struct (field $val i32)))
(import "m" "tbl" (table 1 funcref))
(elem (i32.const 0) $f1)
(func $f1 (param (ref null $box)) (unreachable)))`),
WebAssembly.CompileError,
/cannot expose indexed reference type/);
assertErrorMessage(() => wasmCompile(
`(module
(type $box (struct (field $val i32)))
(import "m" "tbl" (table 1 funcref))
(elem (i32.const 0) $f1)
(func $f1 (result (ref null $box)) (ref.null $box)))`),
WebAssembly.CompileError,
/cannot expose indexed reference type/);
assertEq(typeof wasmCompile(
`(module
(import "m" "tbl" (table 1 funcref))
(elem (i32.const 0) $f1)
(func $f1 (param eqref) (unreachable)))`),
"object");
assertEq(typeof wasmCompile(
`(module
(import "m" "tbl" (table 1 funcref))
(elem (i32.const 0) $f1)
(func $f1 (result eqref) (ref.null eq)))`),
"object");
// Can't call via exported table with type that is exposed for Ref, though eqref is OK.
assertErrorMessage(() => wasmCompile(
`(module
(type $box (struct (field $val i32)))
(type $fn (func (param (ref null $box))))
(table (export "tbl") 1 funcref)
(func (param i32)
(call_indirect (type $fn) (ref.null $box) (local.get 0))))`),
WebAssembly.CompileError,
/cannot expose indexed reference type/);
assertErrorMessage(() => wasmCompile(
`(module
(type $box (struct (field $val i32)))
(type $fn (func (result (ref null $box))))
(table (export "tbl") 1 funcref)
(func (param i32) (result (ref null $box))
(call_indirect (type $fn) (local.get 0))))`),
WebAssembly.CompileError,
/cannot expose indexed reference type/);
assertEq(typeof wasmCompile(
`(module
(type $fn (func (param eqref)))
(table (export "tbl") 1 funcref)
(func (param i32)
(call_indirect (type $fn) (ref.null eq) (local.get 0))))`),
"object");
assertEq(typeof wasmCompile(
`(module
(type $fn (func (result eqref)))
(table (export "tbl") 1 funcref)
(func (param i32) (result eqref)
(call_indirect (type $fn) (local.get 0))))`),
"object");
// Can't call via imported table with type that is exposed for Ref, though eqref is OK.
assertErrorMessage(() => wasmCompile(
`(module
(type $box (struct (field $val i32)))
(type $fn (func (param (ref null $box))))
(import "m" "tbl" (table 1 funcref))
(func (param i32)
(call_indirect (type $fn) (ref.null $box) (local.get 0))))`),
WebAssembly.CompileError,
/cannot expose indexed reference type/);
assertErrorMessage(() => wasmCompile(
`(module
(type $box (struct (field $val i32)))
(type $fn (func (result (ref null $box))))
(import "m" "tbl" (table 1 funcref))
(func (param i32) (result (ref null $box))
(call_indirect (type $fn) (local.get 0))))`),
WebAssembly.CompileError,
/cannot expose indexed reference type/);
assertEq(typeof wasmCompile(
`(module
(type $fn (func (param eqref)))
(import "m" "tbl" (table 1 funcref))
(func (param i32)
(call_indirect (type $fn) (ref.null eq) (local.get 0))))`),
"object");
assertEq(typeof wasmCompile(
`(module
(type $fn (func (result eqref)))
(import "m" "tbl" (table 1 funcref))
(func (param i32) (result eqref)
(call_indirect (type $fn) (local.get 0))))`),
"object");
// We can call via a private table with a type that is exposed for Ref.
{
let m = wasmCompile(
`(module
(type $box (struct (field $val i32)))
(type $fn (func (param (ref null $box)) (result i32)))
(table 1 funcref)
(elem (i32.const 0) $f1)
(func $f1 (param (ref null $box)) (result i32) (i32.const 37))
(func (export "f") (param i32) (result i32)
(call_indirect (type $fn) (ref.null $box) (local.get 0))))`);
let i = new WebAssembly.Instance(m).exports;
assertEq(i.f(0), 37);
}
|
