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# to you under the Apache License, Version 2.0 (the
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#
#   http://www.apache.org/licenses/LICENSE-2.0
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import pytest

import tvm.testing
from tvm.s_tir.analysis import assert_pure_function, is_pure_function
from tvm.script import tirx as T


class CheckPureFunction:
    def test_check_purity(self):
        assert is_pure_function(self.func)

    def test_assert_purity(self):
        assert_pure_function(self.func)


class CheckImpureFunction:
    def test_check_purity(self):
        assert not is_pure_function(self.func)

    def test_assert_purity(self):
        with pytest.raises(AssertionError):
            assert_pure_function(self.func)


class TestNoOp(CheckPureFunction):
    @T.prim_func(s_tir=True)
    def func():
        pass


class TestReturnValue(CheckPureFunction):
    @T.prim_func(s_tir=True)
    def func() -> T.int32:
        return 42


class TestComputeValueAndReturn(CheckPureFunction):
    @T.prim_func(s_tir=True)
    def func(N: T.int32, M: T.int32) -> T.int32:
        return N * M


class TestReadBufferArgument(CheckPureFunction):
    @T.prim_func(s_tir=True)
    def func(A: T.Buffer(16, "float32")) -> T.float32:
        return A[0]


class TestWriteToBufferArgument(CheckImpureFunction):
    @T.prim_func(s_tir=True)
    def func(A: T.Buffer(16, "float32"), B: T.Buffer(16, "float32")):
        for i in range(16):
            B[i] = A[i]


class TestWriteToInternalAllocation(CheckPureFunction):
    @T.prim_func(s_tir=True)
    def func(A: T.Buffer([16, 16], "float32")) -> T.float32:
        Sum = T.decl_buffer([], "float32")
        Sum[()] = 0.0
        for i, j in T.grid(16, 16):
            Sum[()] = Sum[()] + A[i, j]

        return Sum[()]


class TestCallPureBuiltin(CheckPureFunction):
    @T.prim_func(s_tir=True)
    def func(x: T.float32) -> T.float32:
        return T.cos(x)


class TestCallPureExtern(CheckPureFunction):
    @T.prim_func(s_tir=True)
    def func():
        T.call_pure_extern("some_pure_extern_func_name", dtype="void")


class TestCallImpureExtern(CheckImpureFunction):
    @T.prim_func(s_tir=True)
    def func():
        T.call_extern("some_impure_extern_func_name", dtype="void")


if __name__ == "__main__":
    tvm.testing.main()
