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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 tvm
from tvm import te
from tvm.tir import Buffer
import numpy as np

def test_buffer():
    m = te.size_var('m')
    n = te.size_var('n')
    l = te.size_var('l')
    Ab = tvm.tir.decl_buffer((m, n), "float32")
    Bb = tvm.tir.decl_buffer((n, l), "float32")

    assert isinstance(Ab, tvm.tir.Buffer)
    assert Ab.dtype == "float32"
    assert tuple(Ab.shape) == (m, n)


def test_buffer_access_ptr():
    m = te.size_var('m')
    n = te.size_var('n')
    Ab = tvm.tir.decl_buffer((m, n), "float32", strides=[n + 1 , 1])
    aptr = Ab.access_ptr("rw")
    assert tvm.ir.structural_equal(aptr.args[3], Ab.strides[0] * m)
    assert aptr.args[0].dtype == Ab.dtype
    assert aptr.args[4].value == Buffer.READ | Buffer.WRITE
    aptr = Ab.access_ptr("w")
    assert aptr.args[4].value == Buffer.WRITE


def test_buffer_access_ptr_offset():
    m = te.size_var('m')
    n = te.size_var('n')
    Ab = tvm.tir.decl_buffer((m, n), "float32")
    aptr = Ab.access_ptr("rw", offset=100)
    offset = tvm.tir.ir_pass.Simplify(aptr.args[2])
    assert tvm.ir.structural_equal(offset, 100)
    assert aptr.args[4].value == Buffer.READ | Buffer.WRITE
    v = te.size_var('int32')
    aptr = Ab.access_ptr("rw", offset=100 + 100 + v)
    offset = tvm.tir.ir_pass.Simplify(aptr.args[2])
    assert tvm.ir.structural_equal(offset, 200 + v)
    assert aptr.args[4].value == Buffer.READ | Buffer.WRITE
    aptr = Ab.access_ptr("rw", offset=tvm.tir.call_extern('int32', "test_call", 100 + 100 + v))
    offset = tvm.tir.ir_pass.Simplify(aptr.args[2])
    assert tvm.ir.structural_equal(offset, tvm.tir.call_extern('int32', "test_call", 200 + v))
    assert aptr.args[4].value == Buffer.READ | Buffer.WRITE


def test_buffer_access_ptr_extent():
    m = te.size_var('m')
    n = te.size_var('n')
    Ab = tvm.tir.decl_buffer((m, n), "float32")
    aptr = Ab.access_ptr("rw")
    assert tvm.ir.structural_equal(aptr.args[3], m * n)
    aptr = Ab.access_ptr("rw", offset=100)
    assert tvm.ir.structural_equal(aptr.args[3], m * n - 100)
    Ab = tvm.tir.decl_buffer((m, n), "float32", strides=[n + 1 , 1])
    aptr = Ab.access_ptr("rw", offset=100)
    assert tvm.ir.structural_equal(aptr.args[3], Ab.strides[0] * m - 100)


def test_buffer_vload():
    m = te.size_var('m')
    n = te.size_var('n')
    Ab = tvm.tir.decl_buffer((m, n), "float32", elem_offset=100)
    load = Ab.vload([2, 3])
    offset = tvm.tir.ir_pass.Simplify(load.index)
    assert tvm.ir.structural_equal(offset, n * 2 + 103)


def test_buffer_index_merge_mult_mod():
    m = te.size_var('m')
    n = te.size_var('n')
    s = te.size_var('s')
    k0 = te.size_var('k0')
    k1 = te.size_var('k1')
    A = tvm.tir.decl_buffer((m, n), "float32")
    A_stride = tvm.tir.decl_buffer((m, n), "float32", strides=(s, 1))
    def assert_simplified_equal(index_simplified, index_direct):
        assert tvm.ir.structural_equal(index_simplified, index_direct),\
        "index_simplified=%s, index_direct=%s" %(index_simplified, index_direct)
    idxd = tvm.tir.indexdiv
    idxm = tvm.tir.indexmod
    # Test Case1
    index_simplified = A_stride.vload(
        (idxd(idxm(k0, k1), s), idxm(idxm(k0, k1), s) + idxd(k0, k1) * k1))
    index_direct = A_stride.vload((0, k0))
    assert_simplified_equal(index_simplified, index_direct)

    # Test Case2
    index_simplified = A.vload((idxd(idxm(k0, idxd(k1, s)), n),
                                idxm(idxm(k0, idxd(k1, s)), n) + idxm(k0, k1)))
    index_direct = A.vload((0, idxm(k0, k1) + idxm(k0, idxd(k1, s))))
    assert_simplified_equal(index_simplified, index_direct)
    # Test Case3
    index_simplified = A.vload((idxd((idxd(k0, idxd(k1, s)) * idxd(k1, s)), n) +
                                idxd(idxm(k0, idxd(k1, s)), n),
                                idxm((idxd(k0, idxd(k1, s)) * idxd(k1, s)), n) +
                                idxm(idxm(k0, idxd(k1, s)), n)))
    index_direct = A.vload((0, k0))
    assert_simplified_equal(index_simplified, index_direct)
    # Test Case4 (not able to simplify)
    index_simplified = A.vload((idxd(idxm(k0, idxd(k1, s)), n),
                                idxm(idxm(k0, idxd(k1, n)), n) + idxm(k0, k1)))
    index_direct = A.vload((0, idxd(idxm(k0, idxd(k1, s)), n) * n +
                            (idxm(idxm(k0, idxd(k1, n)), n) + idxm(k0, k1))))
    assert_simplified_equal(index_simplified, index_direct)


def test_buffer_broadcast():
    m0, m1, m2 = te.size_var("m0"), te.size_var("m1"), te.size_var("m2")
    n0, n1, n2 = te.size_var("n0"), te.size_var("n1"), te.size_var("n2")
    o0, o1, o2 = te.size_var("o0"), te.size_var("o1"), te.size_var("o2")

    A = te.placeholder((m0, m1, m2), name='A')
    B = te.placeholder((n0, n1, n2), name='B')

    C = te.compute((o0, o1, o2), lambda i, j, k: A[i, j, k] + B[i, j, k], name='C')

    Ab = tvm.tir.decl_buffer(A.shape, A.dtype, name="Ab", buffer_type="auto_broadcast")
    Bb = tvm.tir.decl_buffer(B.shape, B.dtype, name="Bb", buffer_type="auto_broadcast")
    s = te.create_schedule(C.op)

    def check():
        if not tvm.runtime.enabled("llvm"):
            return
        fadd = tvm.build(s, [A, B, C], target='llvm', name='bcast_add', binds={A:Ab, B:Bb})
        ctx = tvm.cpu(0)
        a = tvm.nd.array(np.random.uniform(size=(2, 4, 3)).astype(A.dtype), ctx)
        b = tvm.nd.array(np.random.uniform(size=(2, 1, 1)).astype(B.dtype), ctx)
        c = tvm.nd.array(np.zeros((2, 4, 3), dtype=C.dtype), ctx)
        fadd(a, b, c)
        tvm.testing.assert_allclose(c.asnumpy(), a.asnumpy() + b.asnumpy())

    check()


def test_buffer_broadcast_expr():
    n0, m0, x = te.size_var('n0'), te.size_var('m0'), te.size_var('x')
    n1, m1 = te.size_var('n1'), te.size_var('m1')
    o0, o1 = te.size_var('o0'), te.size_var('o1')

    A = te.placeholder((m0, n0), name='A')
    B = te.placeholder((m1, n1), name='B')
    C = te.compute((o0, o1//x), lambda i, j: A[i, j] + B[i, j], name='C')

    Ab = tvm.tir.decl_buffer(A.shape, A.dtype, name="Ab", buffer_type="auto_broadcast")
    Bb = tvm.tir.decl_buffer(B.shape, B.dtype, name="Bb", buffer_type="auto_broadcast")
    Cc = tvm.tir.decl_buffer(C.shape, C.dtype, name="Cc", buffer_type="auto_broadcast")
    s = te.create_schedule(C.op)

    def check_stride():
        if not tvm.runtime.enabled("llvm"):
            return
        fadd = tvm.build(s, [A, B, C, o1, x], target='llvm', name='bcast_add',
                         binds={A:Ab, B:Bb, C:Cc})
        ctx = tvm.cpu(0)
        a = tvm.nd.array(np.random.uniform(size=(2, 4)).astype(A.dtype), ctx)
        b = tvm.nd.array(np.random.uniform(size=(2, 4)).astype(B.dtype), ctx)
        c = tvm.nd.array(np.zeros((2, 4), dtype=C.dtype), ctx)
        fadd(a, b, c, 4, 1)
        tvm.testing.assert_allclose(c.asnumpy(), a.asnumpy() + b.asnumpy())

    def check_no_stride():
        if not tvm.runtime.enabled("llvm"):
            return
        fadd = tvm.build(s, [A, B, C, o1, x], target='llvm', name='bcast_add',
                         binds={A: Ab, B: Bb, C: Cc})
        ctx = tvm.cpu(0)
        a = tvm.nd.array(np.random.uniform(size=(1, 4)).astype(A.dtype), ctx)
        b = tvm.nd.array(np.random.uniform(size=(2, 4)).astype(B.dtype), ctx)
        c = tvm.nd.array(np.zeros((2, 4), dtype=C.dtype), ctx)
        fadd(a, b, c, 4, 1)
        tvm.testing.assert_allclose(c.asnumpy(), a.asnumpy() + b.asnumpy())

    def check_auto_bind():
        if not tvm.runtime.enabled("llvm"):
            return
        # Let build bind buffers
        fadd = tvm.build(s, [A, B, C, o1, x], target='llvm', name='bcast_add')
        ctx = tvm.cpu(0)
        a = tvm.nd.array(np.random.uniform(size=(1, 4)).astype(A.dtype), ctx)
        b = tvm.nd.array(np.random.uniform(size=(2, 4)).astype(B.dtype), ctx)
        c = tvm.nd.array(np.zeros((2, 4), dtype=C.dtype), ctx)
        fadd(a, b, c, 4, 1)
        tvm.testing.assert_allclose(c.asnumpy(), a.asnumpy() + b.asnumpy())

    check_stride()
    check_no_stride()
    check_auto_bind()


if __name__ == "__main__":
    test_buffer()
    test_buffer_access_ptr()
    test_buffer_access_ptr_offset()
    test_buffer_access_ptr_extent()
    test_buffer_vload()
    test_buffer_index_merge_mult_mod()
    test_buffer_broadcast()
    test_buffer_broadcast_expr()
