# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements.  See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership.  The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
# under the License.
import pytest

import tvm
import tvm.testing
from tvm import s_tir
from tvm.ir import Range
from tvm.script import tirx as T


@T.prim_func(s_tir=True)
def func() -> None:
    A = T.sblock_alloc_buffer((128, 128), "float32")
    B = T.sblock_alloc_buffer((128, 128), "float32")
    C = T.sblock_alloc_buffer((128, 128), "float32")
    D = T.sblock_alloc_buffer((128, 128), "float32")
    with T.sblock():
        # Need add read/write region manually to avoid triggering block access region detector
        T.reads([B[0, 0], C[0:16, 0:16], A[4:12, 4:12]])
        T.writes([A[0:12, 0:12]])
        for i, j in T.grid(8, 8):
            A[i, j] = B[0, 0] + C[0, 0]
        for i, j in T.grid(2, 2):
            with T.sblock():
                vi, vj = T.axis.remap("SS", [i, j])
                T.reads([A[vi * 4 + 4 : vi * 4 + 8, vj * 4 + 4 : vj * 4 + 8], C[12:16, 12:16]])
                T.writes([A[vi * 4 + 4 : vi * 4 + 8, vj * 4 + 4 : vj * 4 + 8]])
                for i, j in T.grid(4, 4):
                    A[vi * 4 + 4 + i, vj * 4 + 4 + j] += C[i + 12, j + 12]
        T.evaluate(D.data)


@T.prim_func(s_tir=True)
def match_buffer_func() -> None:
    with T.sblock("root"):
        A = T.sblock_alloc_buffer((128, 128), "float32")
        B = T.sblock_alloc_buffer((128, 128), "float32")
        T.reads([])
        T.writes([])
        # Need add read/write region manually to avoid triggering block access region detector
        for i, j in T.grid(8, 8):
            with T.sblock("block"):
                vi, vj = T.axis.remap("SS", [i, j])
                T.reads(B[vi * 16 + 2 : vi * 16 + 12, vj * 16 + 2 : vj * 16 + 16])
                T.writes(A[vi * 16 : vi * 16 + 16, vj * 16 : vj * 16 + 16])
                AA = T.match_buffer(A[vi * 16 : vi * 16 + 16, vj * 16 : vj * 16 + 16], (16, 16))
                B0 = T.match_buffer(B[vi * 16 + 2 : vi * 16 + 6, vj * 16 + 2 : vj * 16 + 6], (4, 4))
                B1 = T.match_buffer(
                    B[vi * 16 + 8 : vi * 16 + 12, vj * 16 + 8 : vj * 16 + 16], (4, 8)
                )
                for ii, jj in T.grid(16, 16):
                    with T.sblock("AAA"):
                        vii, vjj = T.axis.remap("SS", [ii, jj])
                        T.reads([])
                        T.writes(AA[vii, vjj])
                        AAA = T.match_buffer(AA[vii, vjj], ())
                        AAA[()] = 1.0
                T.evaluate(B0.data)
                T.evaluate(B1.data)


@T.prim_func(s_tir=True)
def opaque_block_func() -> None:
    with T.sblock("root"):
        A = T.sblock_alloc_buffer((16, 16), "float32")
        B = T.sblock_alloc_buffer((16, 16), "float32")
        T.reads([])
        T.writes([])
        # Need add read/write region manually to avoid triggering block access region detector
        for i in range(0, 16):
            with T.sblock():
                T.reads(A[i, 0:16])
                T.writes([B[i, 0:16]])
                for j in range(0, 16):
                    with T.sblock():
                        T.reads(A[i, j])
                        T.writes(B[i, j])
                        B[i, j] = A[i, j] + 1.0


@T.prim_func(s_tir=True)
def opaque_access_func() -> None:
    A = T.sblock_alloc_buffer([1024])
    B = T.sblock_alloc_buffer([1024])
    for i in T.serial(0, 8):
        with T.sblock():
            v = T.axis.S(8, i)
            T.reads([A[v * 128 : v * 128 + 128]])
            T.writes([B[v * 128 : v * 128 + 128]])
            T.evaluate(
                T.call_extern("test", B.data, v * 128, 128, A.data, v * 128, 128, dtype="float32")
            )


@T.prim_func(s_tir=True)
def opaque_access_with_tvm_access_ptr_func() -> None:
    A = T.sblock_alloc_buffer([1024])
    B = T.sblock_alloc_buffer([1024])
    C = T.sblock_alloc_buffer([1024])
    with T.sblock("opaque"):
        T.reads(A[0:1024], C[0:1024])
        T.writes(B[0:1024], C[0:1024])
        T.evaluate(A.access_ptr("r"))
        T.evaluate(B.access_ptr("w"))
        T.evaluate(C.access_ptr("rw"))


@T.prim_func(s_tir=True)
def decl_buffer_alias_func(
    A: T.Buffer((16,), "float32"),
    B: T.Buffer((16,), "float32"),
) -> None:
    with T.sblock("alias"):
        T.reads(A[0])
        T.writes(B[0])
        A_view = T.decl_buffer((16,), "float32", data=A.data)
        B[0] = A[0] + A_view[0]


@T.prim_func(s_tir=True)
def access_in_if_then_else_func() -> None:
    A = T.sblock_alloc_buffer([8])
    B = T.sblock_alloc_buffer([8])
    with T.sblock():
        T.reads([A[0:5]])
        T.writes([B[0:8]])
        for i in T.serial(0, 8):
            B[i] = T.if_then_else(i < 5, A[i], 0.0, dtype="float32")


@T.prim_func(s_tir=True)
def access_in_branch_func() -> None:
    A = T.sblock_alloc_buffer([8])
    B = T.sblock_alloc_buffer([8])
    with T.sblock():
        T.reads([A[0:7]])
        T.writes([B[0:8]])
        for i in T.serial(0, 8):
            if i < 5:
                B[i] = A[i] + 1.0
            else:
                B[i] = A[i - 1]


@T.prim_func(s_tir=True)
def gemm() -> None:
    A = T.sblock_alloc_buffer([16, 16], "float32")
    B = T.sblock_alloc_buffer([16, 16], "float32")
    C = T.sblock_alloc_buffer([16, 16], "float32")
    for i, j, k, ii, jj in T.grid(4, 4, 16, 4, 4):
        with T.sblock("update"):
            vi = T.axis.S(16, i * 4 + ii)
            vj = T.axis.S(16, j * 4 + jj)
            vk = T.axis.R(16, k)
            T.reads(A[vi, vk], B[vj, vk])
            T.writes(C[vi, vj])
            with T.init():
                C[vi, vj] = 0
            C[vi, vj] += A[vi, vk] * B[vj, vk]


@T.prim_func(s_tir=True)
def decomposed_gemm() -> None:
    A = T.sblock_alloc_buffer([16, 16], "float32")
    B = T.sblock_alloc_buffer([16, 16], "float32")
    C = T.sblock_alloc_buffer([16, 16], "float32")
    for i, j in T.grid(4, 4):
        for ii, jj in T.grid(4, 4):
            with T.sblock("init"):
                vi = T.axis.S(16, i * 4 + ii)
                vj = T.axis.S(16, j * 4 + jj)
                T.reads([])
                T.writes(C[vi, vj])
                C[vi, vj] = 0
        for k, ii, jj in T.grid(16, 4, 4):
            with T.sblock("update"):
                vi = T.axis.S(16, i * 4 + ii)
                vj = T.axis.S(16, j * 4 + jj)
                vk = T.axis.R(16, k)
                T.reads(C[vi, vj], A[vi, vk], B[vj, vk])
                T.writes(C[vi, vj])
                C[vi, vj] += A[vi, vk] * B[vj, vk]


@T.prim_func(s_tir=True)
def access_of_padding_pattern() -> None:
    X = T.sblock_alloc_buffer([28, 28])
    X_pad = T.sblock_alloc_buffer([32, 32])
    Y = T.sblock_alloc_buffer([28, 28])
    for i, j in T.grid(32, 32):
        with T.sblock("padding"):
            vi, vj = T.axis.remap("SS", [i, j])
            T.reads([X[vi - 2, vj - 2]])
            T.writes([X_pad[vi, vj]])
            X_pad[vi, vj] = T.if_then_else(
                2 <= vi and vi < 30 and 2 <= vj and vj < 30, X[vi - 2, vj - 2], 0.0, dtype="float32"
            )
        with T.sblock("padding_reverse"):
            vi, vj = T.axis.remap("SS", [i, j])
            T.reads([X_pad[vi, vj]])
            T.writes([Y[vi - 2, vj - 2]])
            if 2 <= vi and vi < 30 and 2 <= vj and vj < 30:
                Y[vi - 2, vj - 2] = X_pad[vi, vj]


def test_block_access_region_detector():
    block = func.body.block.body.block
    alloc_buffers = func.body.block.alloc_buffers
    buffer_var_map = {buf: buf for buf in alloc_buffers}
    ret = s_tir.analysis.get_sblock_access_region(block, buffer_var_map)

    tvm.ir.assert_structural_equal(block.reads, ret[0])
    tvm.ir.assert_structural_equal(block.writes, ret[1])
    D = alloc_buffers[-1]
    tvm.ir.assert_structural_equal(
        [tvm.tirx.BufferRegion(D, [Range(0, 128), Range(0, 128)])], ret[2]
    )


def test_opaque_block():
    alloc_buffers = opaque_block_func.body.block.alloc_buffers
    buffer_var_map = {buf: buf for buf in alloc_buffers}

    block0 = opaque_block_func.body.block.body.body.block
    ret = s_tir.analysis.get_sblock_access_region(block0, buffer_var_map)
    tvm.ir.assert_structural_equal(block0.reads, ret[0])
    tvm.ir.assert_structural_equal(block0.writes, ret[1])

    block1 = block0.body.body.block
    ret = s_tir.analysis.get_sblock_access_region(block1, buffer_var_map)
    tvm.ir.assert_structural_equal(block1.reads, ret[0])
    tvm.ir.assert_structural_equal(block1.writes, ret[1])


def test_opaque_access():
    block = opaque_access_func.body.block.body.body.block
    alloc_buffers = opaque_access_func.body.block.alloc_buffers
    buffer_var_map = {buf: buf for buf in alloc_buffers}

    ret0 = s_tir.analysis.get_sblock_read_write_region(block, buffer_var_map)
    ret1 = s_tir.analysis.get_sblock_access_region(block, buffer_var_map)
    with pytest.raises(ValueError):
        tvm.ir.assert_structural_equal(ret0[0], ret1[0])
    with pytest.raises(ValueError):
        tvm.ir.assert_structural_equal(ret0[1], ret1[1])


def test_opaque_access_with_tvm_access_ptr():
    block = opaque_access_with_tvm_access_ptr_func.body.block.body.block
    alloc_buffers = opaque_access_with_tvm_access_ptr_func.body.block.alloc_buffers
    buffer_var_map = {buf: buf for buf in alloc_buffers}

    ret0 = s_tir.analysis.get_sblock_read_write_region(block, buffer_var_map)
    ret1 = s_tir.analysis.get_sblock_access_region(block, buffer_var_map)
    tvm.ir.assert_structural_equal(block.reads, ret0[0])
    tvm.ir.assert_structural_equal(block.writes, ret0[1])
    with pytest.raises(ValueError):
        tvm.ir.assert_structural_equal(ret0[0], ret1[0])
    with pytest.raises(ValueError):
        tvm.ir.assert_structural_equal(ret0[1], ret1[1])


def test_decl_buffer_alias_is_not_an_opaque_access():
    block = decl_buffer_alias_func.body.block
    buffer_var_map = {
        buf: buf for buf in decl_buffer_alias_func.params if tvm.tirx.is_buffer_var(buf)
    }

    reads, writes, opaque = s_tir.analysis.get_sblock_access_region(block, buffer_var_map)
    tvm.ir.assert_structural_equal(block.reads, reads)
    tvm.ir.assert_structural_equal(block.writes, writes)
    tvm.ir.assert_structural_equal([], opaque)


def test_match_buffer():
    root_block = match_buffer_func.body.block
    block = root_block.body.body.body.block
    block_inner = block.body[0].body.body.block
    alloc_buffers = match_buffer_func.body.block.alloc_buffers
    buffer_var_map = {buf: buf for buf in alloc_buffers}

    # Check block
    ret = s_tir.analysis.get_sblock_access_region(block, buffer_var_map)
    tvm.ir.assert_structural_equal(block.writes, ret[1])
    # B is opaque access
    tvm.ir.assert_structural_equal(block.reads, ret[2])

    # Check inner block AAA without updating buffer_var_map
    ret = s_tir.analysis.get_sblock_access_region(block_inner, buffer_var_map)
    # Since AA is not in the buffer_var_map, region of AA will not be collected.
    tvm.ir.assert_structural_equal([], ret[1])

    # Check inner block AAA
    for match_buffer in block.match_buffers:
        target_buffer = match_buffer.buffer
        buffer_var_map[target_buffer] = target_buffer

    ret = s_tir.analysis.get_sblock_access_region(block_inner, buffer_var_map)
    tvm.ir.assert_structural_equal(block_inner.reads, ret[0])
    tvm.ir.assert_structural_equal(block_inner.writes, ret[1])


def test_access_in_if_then_else_func():
    block = access_in_if_then_else_func.body.block.body.block
    alloc_buffers = access_in_if_then_else_func.body.block.alloc_buffers
    buffer_var_map = {buf: buf for buf in alloc_buffers}
    ret0 = s_tir.analysis.get_sblock_read_write_region(block, buffer_var_map)
    ret1 = s_tir.analysis.get_sblock_access_region(block, buffer_var_map)
    tvm.ir.assert_structural_equal(ret0[0], ret1[0])
    tvm.ir.assert_structural_equal(ret0[1], ret1[1])


def test_access_in_branch_func():
    block = access_in_branch_func.body.block.body.block
    alloc_buffers = access_in_branch_func.body.block.alloc_buffers
    buffer_var_map = {buf: buf for buf in alloc_buffers}
    ret0 = s_tir.analysis.get_sblock_read_write_region(block, buffer_var_map)
    ret1 = s_tir.analysis.get_sblock_access_region(block, buffer_var_map)
    tvm.ir.assert_structural_equal(ret0[0], ret1[0])
    tvm.ir.assert_structural_equal(ret0[1], ret1[1])


def test_access_of_padding_pattern():
    s = tvm.s_tir.schedule.Schedule(access_of_padding_pattern)
    alloc_buffers = s.get_sref(s.get_sblock("root")).stmt.alloc_buffers
    buffer_var_map = {buf: buf for buf in alloc_buffers}

    def do_compare_buffer_region(region, expect):
        assert region.buffer == expect.buffer
        analyzer = tvm.arith.Analyzer()
        for observed_range, expected_range in zip(region.region, expect.region):
            analyzer.can_prove_equal(observed_range.min, expected_range.min)
            analyzer.can_prove_equal(observed_range.extent, expected_range.extent)

    def do_check_block(block_name):
        block = s.get_sref(s.get_sblock(block_name)).stmt
        expect_reads = block.reads
        expect_writes = block.writes
        ret = s_tir.analysis.get_sblock_access_region(block, buffer_var_map)
        for i, read in enumerate(ret[0]):
            do_compare_buffer_region(read, expect_reads[i])
        for i, write in enumerate(ret[1]):
            do_compare_buffer_region(write, expect_writes[i])

    do_check_block("padding")
    do_check_block("padding_reverse")


def test_access_of_reduction():
    block = gemm.body.block.body.body.body.body.body.body.block
    alloc_buffers = gemm.body.block.alloc_buffers
    buffer_var_map = {buf: buf for buf in alloc_buffers}
    ret = s_tir.analysis.get_sblock_access_region(block, buffer_var_map)
    tvm.ir.assert_structural_equal(block.reads, ret[0])
    tvm.ir.assert_structural_equal(block.writes, ret[1])


def test_access_of_decompose_reduction():
    init = decomposed_gemm.body.block.body.body.body[0].body.body.block
    update = decomposed_gemm.body.block.body.body.body[1].body.body.body.block
    alloc_buffers = decomposed_gemm.body.block.alloc_buffers
    buffer_var_map = {buf: buf for buf in alloc_buffers}
    for block in [init, update]:
        ret = s_tir.analysis.get_sblock_access_region(block, buffer_var_map)
        tvm.ir.assert_structural_equal(block.reads, ret[0])
        tvm.ir.assert_structural_equal(block.writes, ret[1])


def test_buffer_access_with_let_binding():
    @T.prim_func(s_tir=True)
    def func(
        storage: T.Buffer((16, 16, 16), "float32"),
        seq_slot_ids: T.Buffer((16,), "int32"),
        history_slot_ids: T.Buffer((16,), "int32"),
        output: T.Buffer((16, 16), "float32"),
    ):
        for i, s in T.grid(16, 16):
            with T.sblock("copy"):
                vi, vs = T.axis.remap("SS", [i, s])
                T.reads(
                    seq_slot_ids[vi],
                    history_slot_ids[vi],
                    storage[seq_slot_ids[vi], history_slot_ids[vi], vs],
                )
                T.writes(output[vi, vs])
                seq_id: T.let[T.int32] = seq_slot_ids[vi]
                history_id: T.let[T.int32] = history_slot_ids[vi]
                output[vi, vs] = storage[seq_id, history_id, vs]

    block = func.body.block.body.body.body.block
    buffer_var_map = {buf: buf for buf in func.params if tvm.tirx.is_buffer_var(buf)}
    ret = s_tir.analysis.get_sblock_access_region(block, buffer_var_map)
    tvm.ir.assert_structural_equal(block.reads, ret[0])
    tvm.ir.assert_structural_equal(block.writes, ret[1])


def test_buffer_access_with_nested_let_binding():
    @T.prim_func(s_tir=True)
    def func(
        A: T.Buffer((16, 16), "float32"),
        B: T.Buffer((16, 16), "float32"),
        C: T.Buffer((16, 16), "float32"),
    ):
        for i, s in T.grid(16, 16):
            with T.sblock("copy"):
                vi, vs = T.axis.remap("SS", [i, s])
                T.reads(A[vi, vs], B[vi, vs])
                T.writes(C[vi, vs])
                vi1: T.let[T.int32] = vi
                vi2: T.let[T.int32] = vi1
                vs1: T.let[T.int32] = vs
                vs2: T.let[T.int32] = vs1
                vs3: T.let[T.int32] = vs2
                C[vi, vs1] = A[vi1, vs2] + B[vi2, vs3]

    block = func.body.block.body.body.body.block
    buffer_var_map = {buf: buf for buf in func.params if tvm.tirx.is_buffer_var(buf)}
    ret = s_tir.analysis.get_sblock_access_region(block, buffer_var_map)
    tvm.ir.assert_structural_equal(block.reads, ret[0])
    tvm.ir.assert_structural_equal(block.writes, ret[1])


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