Improve error message for unsupported parfor args

[diptorupd]

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Improve error message for unsupported parfor args

• Instead of raising a NotImplementedError, we now raise a more informative numba_dpex.core.exceptions.UnsupportedKernelArgumentError if a unsupported argument type is encountered.

Reproducer:

import numpy as np
import dpnp
from numba_dpex import prange, dpjit

@dpjit
def test(a, b, scalar):
    dtype = a.dtype

    for i in prange(a.shape[0]):
        c = dtype.type(0.25) * scalar
        b[i] = c * a[i]


dtype: np.dtype = np.dtype("float")
SCALAR = dtype.type(0.5)

a = dpnp.ones(1024)
b = dpnp.zeros(1024)

test(a, b, SCALAR)

Before

Traceback (most recent call last):
  File "/home/diptorupd/Desktop/devel/numba-dpex/driver.py", line 25, in <module>
    test(a, b, SCALAR)
...
  File "/home/diptorupd/miniconda3/envs/dpex-devel/lib/python3.10/site-packages/numba/core/lowering.py", line 285, in lower_block
    self.lower_inst(inst)
  File "/home/diptorupd/miniconda3/envs/dpex-devel/lib/python3.10/site-packages/numba/parfors/parfor_lowering.py", line 51, in lower_inst
    _lower_parfor_parallel(self, inst)
  File "/home/diptorupd/miniconda3/envs/dpex-devel/lib/python3.10/site-packages/numba/parfors/parfor_lowering.py", line 60, in _lower_parfor_parallel
    return parfor.lowerer(lowerer, parfor)
  File "/home/diptorupd/Desktop/devel/numba-dpex/numba_dpex/core/parfors/parfor_lowerer.py", line 500, in _lower_parfor_as_kernel
    self._submit_parfor_kernel(
  File "/home/diptorupd/Desktop/devel/numba-dpex/numba_dpex/core/parfors/parfor_lowerer.py", line 198, in _submit_parfor_kernel
    self._build_kernel_arglist(kernel_fn, lowerer)
  File "/home/diptorupd/Desktop/devel/numba-dpex/numba_dpex/core/parfors/parfor_lowerer.py", line 172, in _build_kernel_arglist
    self.kernel_builder.build_arg(
  File "/home/diptorupd/Desktop/devel/numba-dpex/numba_dpex/core/utils/kernel_launcher.py", line 154, in build_arg
    numba_type_to_dpctl_typenum(
  File "/home/diptorupd/Desktop/devel/numba-dpex/numba_dpex/dpctl_iface/_helpers.py", line 48, in numba_type_to_dpctl_typenum
    raise NotImplementedError
NotImplementedError

After:

Traceback (most recent call last):
  File "/home/diptorupd/Desktop/devel/numba-dpex/driver.py", line 25, in <module>
    test(a, b, SCALAR)
 ...
  File "/home/diptorupd/miniconda3/envs/dpex-devel/lib/python3.10/site-packages/numba/core/lowering.py", line 187, in lower
    self.lower_normal_function(self.fndesc)
  File "/home/diptorupd/miniconda3/envs/dpex-devel/lib/python3.10/site-packages/numba/core/lowering.py", line 241, in lower_normal_function
    entry_block_tail = self.lower_function_body()
  File "/home/diptorupd/miniconda3/envs/dpex-devel/lib/python3.10/site-packages/numba/core/lowering.py", line 271, in lower_function_body
    self.lower_block(block)
  File "/home/diptorupd/miniconda3/envs/dpex-devel/lib/python3.10/site-packages/numba/core/lowering.py", line 285, in lower_block
    self.lower_inst(inst)
  File "/home/diptorupd/miniconda3/envs/dpex-devel/lib/python3.10/site-packages/numba/parfors/parfor_lowering.py", line 51, in lower_inst
    _lower_parfor_parallel(self, inst)
  File "/home/diptorupd/miniconda3/envs/dpex-devel/lib/python3.10/site-packages/numba/parfors/parfor_lowering.py", line 60, in _lower_parfor_parallel
    return parfor.lowerer(lowerer, parfor)
  File "/home/diptorupd/Desktop/devel/numba-dpex/numba_dpex/core/parfors/parfor_lowerer.py", line 500, in _lower_parfor_as_kernel
    self._submit_parfor_kernel(
  File "/home/diptorupd/Desktop/devel/numba-dpex/numba_dpex/core/parfors/parfor_lowerer.py", line 198, in _submit_parfor_kernel
    self._build_kernel_arglist(kernel_fn, lowerer)
  File "/home/diptorupd/Desktop/devel/numba-dpex/numba_dpex/core/parfors/parfor_lowerer.py", line 172, in _build_kernel_arglist
    self.kernel_builder.build_arg(
  File "/home/diptorupd/Desktop/devel/numba-dpex/numba_dpex/core/utils/kernel_launcher.py", line 154, in build_arg
    numba_type_to_dpctl_typenum(
  File "/home/diptorupd/Desktop/devel/numba-dpex/numba_dpex/dpctl_iface/_helpers.py", line 45, in numba_type_to_dpctl_typenum
    raise UnsupportedKernelArgumentError(
numba_dpex.core.exceptions.UnsupportedKernelArgumentError: Argument $dtype.12 passed to kernel __dpex_parfor_kernel_0 is of an unsupported type (<class 'numba.core.types.npytypes.DType'>). Allowed kernel arguments must be sub-types of numba.types.Number or sub-types of numba_dpex.USMNdArray

• Have you added a test, reproducer or referred to an issue with a reproducer?
• Have you tested your changes locally for CPU and GPU devices?
• Have you made sure that new changes do not introduce compiler warnings?
• If this PR is a work in progress, are you filing the PR as a draft?

[diptorupd]

Too bitrotten