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"""Test code for bitserial_dense operator"""
import os
import numpy as np
import tvm
from tvm import te
import topi
import topi.testing
from topi.util import get_const_tuple
from tvm.contrib.pickle_memoize import memoize

_bitserial_dense_implement = {
    "generic": (topi.nn.bitserial_dense, topi.generic.schedule_bitserial_dense),
    "cpu": (topi.x86.bitserial_dense, topi.x86.schedule_bitserial_dense),
    "arm_cpu": (topi.arm_cpu.bitserial_dense, topi.arm_cpu.schedule_bitserial_dense),
}

def generate_quantized_np(shape, bits, out_dtype):
    min_val = 0
    max_val = 1 << bits
    return np.random.randint(min_val, max_val, size=shape).astype(out_dtype)

def verify_bitserial_dense(batch, in_dim, out_dim, activation_bits, weight_bits, unipolar):
    out_dtype = 'int16'

    def get_ref_data(a_shape, b_shape, input_dtype):
        a_np = generate_quantized_np(get_const_tuple(a_shape), activation_bits, input_dtype)
        b_np = generate_quantized_np(get_const_tuple(b_shape), weight_bits, input_dtype)
        if unipolar:
            b_ = np.copy(b_np).astype(out_dtype)
            for x in np.nditer(b_, op_flags=['readwrite']):
                x[...] = 1 if x == 1 else -1
            c_np = np.dot(a_np, b_.T)
        else:
            c_np = np.dot(a_np, b_np.T)
        return a_np, b_np, c_np

    for target in ["llvm", "llvm -device=arm_cpu"]:
        if "arm_cpu" in target and 'arm' not in os.uname()[4]:
            print ("Skipped running code, not an arm device")
            continue
        input_dtype = 'uint8' if "arm_cpu" in target else "uint32"
        A = te.placeholder((batch, in_dim), dtype=input_dtype, name='A')
        B = te.placeholder((out_dim, in_dim), dtype=input_dtype, name='B')
        fcompute, fschedule = topi.testing.dispatch(target, _bitserial_dense_implement)
        C = fcompute(A, B, activation_bits, weight_bits,
                     input_dtype, out_dtype, unipolar)
        s = fschedule([C])

        a_shape = get_const_tuple(A.shape)
        b_shape = get_const_tuple(B.shape)
        a_np, b_np, c_np = get_ref_data(a_shape, b_shape, input_dtype)

        ctx = tvm.cpu(0)
        a = tvm.nd.array(a_np, ctx)
        b = tvm.nd.array(b_np, ctx)
        c = tvm.nd.array(np.zeros(get_const_tuple(C.shape), dtype=C.dtype), ctx)
        func = tvm.build(s, [A, B, C], target)
        func(a, b, c)
        tvm.testing.assert_allclose(c.asnumpy(), c_np, rtol=1e-5)

def test_bitserial_dense():
    verify_bitserial_dense(1, 1024, 1000, 1, 1, True)
    verify_bitserial_dense(1, 1024, 1000, 2, 1, True)

    verify_bitserial_dense(1, 1024, 1000, 1, 1, False)
    verify_bitserial_dense(1, 1024, 1000, 2, 1, False)

if __name__ == "__main__":
    test_bitserial_dense()
