diff --git a/doc/ref_transform.rst b/doc/ref_transform.rst
index 4a07b63330747aa69d7ed498e004d60b7c312a7b..d293e3ebe998a632bd547f94a67e675ff0592bfb 100644
--- a/doc/ref_transform.rst
+++ b/doc/ref_transform.rst
@@ -72,6 +72,8 @@ Manipulating Instructions
.. autofunction:: tag_instructions
+.. autofunction:: add_nosync
+
Registering Library Routines
----------------------------
diff --git a/doc/tutorial.rst b/doc/tutorial.rst
index 942c7d56e01f9d037b0e2b601f88bc8b96dda151..5eaa12b8124f86cfaf08cf2e83c3382861d9e0f2 100644
--- a/doc/tutorial.rst
+++ b/doc/tutorial.rst
@@ -1479,6 +1479,8 @@ Barriers
:mod:`loopy` may infer the need for a barrier when it is not necessary. The
``no_sync_with`` instruction attribute can be used to resolve this.
+See also :func:`loopy.add_nosync`.
+
TODO
.. }}}
diff --git a/loopy/__init__.py b/loopy/__init__.py
index 6cbb3362ef91b27c3b7b1cf6a591f7f9a20c2f7a..53dd9c8eed796f3f191c21589f1095d468bac772 100644
--- a/loopy/__init__.py
+++ b/loopy/__init__.py
@@ -75,7 +75,8 @@ from loopy.transform.instruction import (
set_instruction_priority, add_dependency,
remove_instructions,
replace_instruction_ids,
- tag_instructions)
+ tag_instructions,
+ add_nosync)
from loopy.transform.data import (
add_prefetch, change_arg_to_image,
@@ -189,6 +190,7 @@ __all__ = [
"remove_instructions",
"replace_instruction_ids",
"tag_instructions",
+ "add_nosync",
"extract_subst", "expand_subst", "assignment_to_subst",
"find_rules_matching", "find_one_rule_matching",
diff --git a/loopy/transform/instruction.py b/loopy/transform/instruction.py
index 7c9c9688604179dce2aa7dcd6954d76a0df32cc7..2be78f8e5c25a3b48c195f52715f9d6453100e3b 100644
--- a/loopy/transform/instruction.py
+++ b/loopy/transform/instruction.py
@@ -34,7 +34,6 @@ def find_instructions(kernel, insn_match):
match = parse_match(insn_match)
return [insn for insn in kernel.instructions if match(kernel, insn)]
-
# }}}
@@ -130,6 +129,8 @@ def remove_instructions(kernel, insn_ids):
Dependencies across (one, for now) deleted isntructions are propagated.
Behavior is undefined for now for chains of dependencies within the
set of deleted instructions.
+
+ This also updates *no_sync_with* for all instructions.
"""
if not insn_ids:
@@ -155,7 +156,14 @@ def remove_instructions(kernel, insn_ids):
for dep_id in depends_on & insn_ids:
new_deps = new_deps | id_to_insn[dep_id].depends_on
- new_insns.append(insn.copy(depends_on=frozenset(new_deps)))
+ # update no_sync_with
+
+ new_no_sync_with = frozenset((insn_id, scope)
+ for insn_id, scope in insn.no_sync_with
+ if insn_id not in insn_ids)
+
+ new_insns.append(
+ insn.copy(depends_on=new_deps, no_sync_with=new_no_sync_with))
return kernel.copy(
instructions=new_insns)
@@ -171,6 +179,7 @@ def replace_instruction_ids(kernel, replacements):
for insn in kernel.instructions:
changed = False
new_depends_on = []
+ new_no_sync_with = []
for dep in insn.depends_on:
if dep in replacements:
@@ -179,8 +188,18 @@ def replace_instruction_ids(kernel, replacements):
else:
new_depends_on.append(dep)
+ for insn_id, scope in insn.no_sync_with:
+ if insn_id in replacements:
+ new_no_sync_with.extend(
+ (repl, scope) for repl in replacements[insn_id])
+ changed = True
+ else:
+ new_no_sync_with.append((insn_id, scope))
+
new_insns.append(
- insn.copy(depends_on=frozenset(new_depends_on))
+ insn.copy(
+ depends_on=frozenset(new_depends_on),
+ no_sync_with=frozenset(new_no_sync_with))
if changed else insn)
return kernel.copy(instructions=new_insns)
@@ -207,4 +226,79 @@ def tag_instructions(kernel, new_tag, within=None):
# }}}
+# {{{ add nosync
+
+def add_nosync(kernel, scope, source, sink, bidirectional=False, force=False):
+ """Add a *no_sync_with* directive between *source* and *sink*.
+ *no_sync_with* is only added if *sink* depends on *source* or
+ if the instruction pair is in a conflicting group.
+
+ This function does not check for the presence of a memory dependency.
+
+ :arg kernel: The kernel
+ :arg source: Either a single instruction id, or any instruction id
+ match understood by :func:`loopy.match.parse_match`.
+ :arg sink: Either a single instruction id, or any instruction id
+ match understood by :func:`loopy.match.parse_match`.
+ :arg scope: A valid *no_sync_with* scope. See
+ :attr:`loopy.InstructionBase.no_sync_with` for allowable scopes.
+ :arg bidirectional: A :class:`bool`. If *True*, add a *no_sync_with*
+ to both the source and sink instructions, otherwise the directive
+ is only added to the sink instructions.
+ :arg force: A :class:`bool`. If *True*, add a *no_sync_with* directive
+ even without the presence of a dependency edge or conflicting
+ instruction group.
+
+ :return: The updated kernel
+ """
+
+ if isinstance(source, str) and source in kernel.id_to_insn:
+ sources = frozenset([source])
+ else:
+ sources = frozenset(
+ source.id for source in find_instructions(kernel, source))
+
+ if isinstance(sink, str) and sink in kernel.id_to_insn:
+ sinks = frozenset([sink])
+ else:
+ sinks = frozenset(
+ sink.id for sink in find_instructions(kernel, sink))
+
+ def insns_in_conflicting_groups(insn1_id, insn2_id):
+ insn1 = kernel.id_to_insn[insn1_id]
+ insn2 = kernel.id_to_insn[insn2_id]
+ return (
+ bool(insn1.groups & insn2.conflicts_with_groups)
+ or
+ bool(insn2.groups & insn1.conflicts_with_groups))
+
+ from collections import defaultdict
+ nosync_to_add = defaultdict(set)
+
+ for sink in sinks:
+ for source in sources:
+
+ needs_nosync = force or (
+ source in kernel.recursive_insn_dep_map()[sink]
+ or insns_in_conflicting_groups(source, sink))
+
+ if not needs_nosync:
+ continue
+
+ nosync_to_add[sink].add((source, scope))
+ if bidirectional:
+ nosync_to_add[source].add((sink, scope))
+
+ new_instructions = list(kernel.instructions)
+
+ for i, insn in enumerate(new_instructions):
+ if insn.id in nosync_to_add:
+ new_instructions[i] = insn.copy(no_sync_with=insn.no_sync_with
+ | frozenset(nosync_to_add[insn.id]))
+
+ return kernel.copy(instructions=new_instructions)
+
+# }}}
+
+
# vim: foldmethod=marker
diff --git a/test/test_transform.py b/test/test_transform.py
index ac5a26f6a5683bf9e86055a2729ea5ee995dee1e..b5fcdf04c4781c5f370c911ceb7efcb4042f6b4e 100644
--- a/test/test_transform.py
+++ b/test/test_transform.py
@@ -402,6 +402,42 @@ def test_precompute_with_preexisting_inames_fail():
precompute_inames="ii,jj")
+def test_add_nosync():
+ orig_knl = lp.make_kernel("{[i]: 0<=i<10}",
+ """
+ <>tmp[i] = 10 {id=insn1}
+ <>tmp2[i] = 10 {id=insn2}
+
+ <>tmp3[2*i] = 0 {id=insn3}
+ <>tmp4 = 1 + tmp3[2*i] {id=insn4}
+
+ <>tmp5[i] = 0 {id=insn5,groups=g1}
+ tmp5[i] = 1 {id=insn6,conflicts=g1}
+ """)
+
+ orig_knl = lp.set_temporary_scope(orig_knl, "tmp3", "local")
+ orig_knl = lp.set_temporary_scope(orig_knl, "tmp5", "local")
+
+ # No dependency present - don't add nosync
+ knl = lp.add_nosync(orig_knl, "any", "writes:tmp", "writes:tmp2")
+ assert frozenset() == knl.id_to_insn["insn2"].no_sync_with
+
+ # Dependency present
+ knl = lp.add_nosync(orig_knl, "local", "writes:tmp3", "reads:tmp3")
+ assert frozenset() == knl.id_to_insn["insn3"].no_sync_with
+ assert frozenset([("insn3", "local")]) == knl.id_to_insn["insn4"].no_sync_with
+
+ # Bidirectional
+ knl = lp.add_nosync(
+ orig_knl, "local", "writes:tmp3", "reads:tmp3", bidirectional=True)
+ assert frozenset([("insn4", "local")]) == knl.id_to_insn["insn3"].no_sync_with
+ assert frozenset([("insn3", "local")]) == knl.id_to_insn["insn4"].no_sync_with
+
+ # Groups
+ knl = lp.add_nosync(orig_knl, "local", "insn5", "insn6")
+ assert frozenset([("insn5", "local")]) == knl.id_to_insn["insn6"].no_sync_with
+
+
if __name__ == "__main__":
if len(sys.argv) > 1:
exec(sys.argv[1])