Move prange utils in separate PR (#612)

Author: densmirn

sdc/utilities/prange_utils.py

@@ -0,0 +1,89 @@
+# *****************************************************************************
+# Copyright (c) 2020, Intel Corporation All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+#
+#     Redistributions of source code must retain the above copyright notice,
+#     this list of conditions and the following disclaimer.
+#
+#     Redistributions in binary form must reproduce the above copyright notice,
+#     this list of conditions and the following disclaimer in the documentation
+#     and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
+# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+# EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+# OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+# WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+# OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+# EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# *****************************************************************************
+
+
+import numba
+import sdc
+
+from typing import NamedTuple
+from sdc.utilities.utils import sdc_overload
+
+
+class Chunk(NamedTuple):
+    start: int
+    stop: int
+
+
+def get_pool_size():
+    if sdc.config.config_use_parallel_overloads:
+        return numba.config.NUMBA_NUM_THREADS
+
+    return 1
+
+
+@sdc_overload(get_pool_size)
+def get_pool_size_overload():
+    pool_size = get_pool_size()
+
+    def get_pool_size_impl():
+        return pool_size
+
+    return get_pool_size_impl
+
+
+def get_chunks(size, pool_size=0):
+    if pool_size == 0:
+        pool_size = get_pool_size()
+
+    chunk_size = (size - 1) // pool_size + 1
+
+    chunks = []
+    for i in range(pool_size):
+        start = min(i * chunk_size, size)
+        stop = min((i + 1) * chunk_size, size)
+        chunks.append(Chunk(start, stop))
+
+    return chunks
+
+
+@sdc_overload(get_chunks)
+def get_chunks_overload(size, pool_size=0):
+    def get_chunks_impl(size, pool_size=0):
+        if pool_size == 0:
+            pool_size = get_pool_size()
+
+        chunk_size = (size - 1) // pool_size + 1
+
+        chunks = []
+        for i in range(pool_size):
+            start = min(i * chunk_size, size)
+            stop = min((i + 1) * chunk_size, size)
+            chunk = Chunk(start, stop)
+            chunks.append(chunk)
+
+        return chunks
+
+    return get_chunks_impl