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// |jit-test| skip-if: !wasmGcEnabled()
// Validate rules for function subtyping:
// - Same number of parameters and results
// - Function return types are covariant
// - Function parameter types are contravariant
wasmValidateText(
`(module
(type $A (sub (struct (field i32))))
(type $B (sub $A (struct (field i32) (field i32))))
(type $C (sub $B (struct (field i32) (field i32) (field i64))))
(type $D (sub $B (struct (field i32) (field i32) (field f32))))
;; Same types (invariant)
(type $func1 (sub (func (param (ref $A) (ref $A)) (result (ref $C)))))
(type $func2 (sub $func1 (func (param (ref $A) (ref $A)) (result (ref $C)))))
;; Covariant return types are valid
(type $func3 (sub (func (param (ref $A) (ref $A)) (result (ref $B)))))
(type $func4 (sub $func3 (func (param (ref $A) (ref $A)) (result (ref $C)))))
(type $func5 (sub (func (param (ref $A) (ref $A)) (result (ref $A) (ref $B)))))
(type $func6 (sub $func5 (func (param (ref $A) (ref $A)) (result (ref $D) (ref $C)))))
;; Contravariant parameter types are valid
(type $func7 (sub (func (param (ref $A) (ref $C)) (result (ref $C)))))
(type $func8 (sub $func7 (func (param (ref $A) (ref $B)) (result (ref $C)))))
(type $func9 (sub (func (param (ref $D) (ref $C)) (result (ref $C)))))
(type $func10 (sub $func9 (func (param (ref $A) (ref $B)) (result (ref $C)))))
;; Mixing covariance and contravariance
(type $func11 (sub (func (param (ref $D) (ref $C)) (result (ref $A)))))
(type $func12 (sub $func11 (func (param (ref $A) (ref $B)) (result (ref $C)))))
)
`);
// Validate that incorrect subtyping examples are failing as expected
const typeError = /incompatible super type/;
var code =`
(module
(type $A (struct (field i32)))
(type $B (sub $A (struct (field i32) (field i32))))
(type $C (sub $B (struct (field i32) (field i32) (field i64))))
(type $D (sub $B (struct (field i32) (field i32) (field f32))))
;; Not the same number of arguments/results
(type $func1 (func (param (ref $A) (ref $A)) (result (ref $C))))
(type $func2 (sub $func1 (func (param (ref $A) (ref $A)) (result (ref $C) (ref $A)))))
)`;
wasmFailValidateText(code, typeError);
code =`
(module
(type $A (sub (struct (field i32))))
(type $B (sub $A (struct (field i32) (field i32))))
(type $C (sub $B (struct (field i32) (field i32) (field i64))))
(type $D (sub $B (struct (field i32) (field i32) (field f32))))
;; Contravariant result types are invalid
(type $func3 (sub (func (param (ref $A) (ref $A)) (result (ref $C)))))
(type $func4 (sub $func3 (func (param (ref $A) (ref $A)) (result (ref $A)))))
)`;
wasmFailValidateText(code, typeError);
code =`
(module
(type $A (sub (struct (field i32))))
(type $B (sub $A (struct (field i32) (field i32))))
(type $C (sub $B (struct (field i32) (field i32) (field i64))))
(type $D (sub $B (struct (field i32) (field i32) (field f32))))
;; Covariant parameters are invalid
(type $func5 (sub (func (param (ref $A) (ref $A)) (result (ref $C)))))
(type $func6 (sub $func5 (func (param (ref $B) (ref $A)) (result (ref $C)))))
)`;
wasmFailValidateText(code, typeError);