def _get_reduction_source(
ctx, out_type, out_type_size,
neutral, reduce_expr, map_expr, parsed_args,
name="reduce_kernel", preamble="", arg_prep="",
device=None, max_group_size=None):
if device is not None:
devices = [device]
else:
devices = ctx.devices
# {{{ compute group size
def get_dev_group_size(device):
# dirty fix for the RV770 boards
max_work_group_size = device.max_work_group_size
if "RV770" in device.name:
max_work_group_size = 64
# compute lmem limit
from pytools import div_ceil
lmem_wg_size = div_ceil(max_work_group_size, out_type_size)
result = min(max_work_group_size, lmem_wg_size)
# round down to power of 2
from pyopencl.tools import bitlog2
return 2**bitlog2(result)
group_size = min(get_dev_group_size(dev) for dev in devices)
if max_group_size is not None:
group_size = min(max_group_size, group_size)
# }}}
from mako.template import Template
from pytools import all
from pyopencl.characterize import has_double_support
src = str(Template(KERNEL).render(
out_type=out_type,
arguments=", ".join(arg.declarator() for arg in parsed_args),
group_size=group_size,
neutral=neutral,
reduce_expr=_process_code_for_macro(reduce_expr),
map_expr=_process_code_for_macro(map_expr),
name=name,
preamble=preamble,
arg_prep=arg_prep,
double_support=all(has_double_support(dev) for dev in devices),
))
from pytools import Record
class ReductionInfo(Record):
pass
return ReductionInfo(
context=ctx,
source=src,
group_size=group_size)
