From 8eb5aa1890248485b160794b47656ebcc8148b31 Mon Sep 17 00:00:00 2001
From: Matt Wala <wala1@illinois.edu>
Date: Fri, 9 Jun 2017 23:08:03 -0500
Subject: [PATCH 1/2] get_usable_inames_for_conditional(): Only pull in inames
 that are common to all instructions in the block.

Closes #71 on gitlab
---
 loopy/codegen/bounds.py | 39 +++++++++++++++++++++++++++++----------
 test/test_loopy.py      | 26 ++++++++++++++++++++++++++
 2 files changed, 55 insertions(+), 10 deletions(-)

diff --git a/loopy/codegen/bounds.py b/loopy/codegen/bounds.py
index 61f4b3a9b..93a34d233 100644
--- a/loopy/codegen/bounds.py
+++ b/loopy/codegen/bounds.py
@@ -58,7 +58,6 @@ def get_approximate_convex_bounds_checks(domain, check_inames, implemented_domai
 def get_usable_inames_for_conditional(kernel, sched_index):
     from loopy.schedule import (
         find_active_inames_at, get_insn_ids_for_block_at, has_barrier_within)
-    from loopy.kernel.data import ParallelTag, LocalIndexTagBase, IlpBaseTag
 
     result = find_active_inames_at(kernel, sched_index)
     crosses_barrier = has_barrier_within(kernel, sched_index)
@@ -78,15 +77,35 @@ def get_usable_inames_for_conditional(kernel, sched_index):
         # Outside all subkernels - use only inames available to host.
         return frozenset(result)
 
-    insn_ids_for_subkernel = get_insn_ids_for_block_at(
-        kernel.schedule, subkernel_index)
+    insn_ids_for_block = list(
+        get_insn_ids_for_block_at(kernel.schedule, subkernel_index))
+
+    # Iterate through the block, and pick out the common set of admissible inames.
+    #
+    # The admissible inames must be common to all instructions in the block to
+    # ensure that constraints from irrelevant inames don't get pulled into the
+    # conditional.
+
+    if len(insn_ids_for_block) == 0:
+        return frozenset(result)
+
+    common_admissible_inames = _pick_out_admissible_inames(
+            kernel, insn_ids_for_block[0], crosses_barrier)
 
-    inames_for_subkernel = (
-        iname
-        for insn in insn_ids_for_subkernel
-        for iname in kernel.insn_inames(insn))
+    from itertools import islice
+    for insn_id in islice(insn_ids_for_block, 1, None):
+        common_admissible_inames &= kernel.insn_inames(insn_id)
+
+    return frozenset(result | common_admissible_inames)
+
+
+def _pick_out_admissible_inames(kernel, insn_id, crosses_barrier):
+    # Given an instruction, pick out the set of (parallel) inames on
+    # which a conditional may depend.
+    from loopy.kernel.data import ParallelTag, LocalIndexTagBase, IlpBaseTag
+    admissible_inames = []
 
-    for iname in inames_for_subkernel:
+    for iname in kernel.insn_inames(insn_id):
         tag = kernel.iname_to_tag.get(iname)
 
         # Parallel inames are defined within a subkernel, BUT:
@@ -101,9 +120,9 @@ def get_usable_inames_for_conditional(kernel, sched_index):
                 and not (isinstance(tag, LocalIndexTagBase) and crosses_barrier)
                 and not isinstance(tag, IlpBaseTag)
                 ):
-            result.add(iname)
+            admissible_inames.append(iname)
 
-    return frozenset(result)
+    return set(admissible_inames)
 
 # }}}
 
diff --git a/test/test_loopy.py b/test/test_loopy.py
index 21db62610..921fe8a4a 100644
--- a/test/test_loopy.py
+++ b/test/test_loopy.py
@@ -2321,6 +2321,32 @@ def test_inames_conditional_generation(ctx_factory):
         knl(queue)
 
 
+def test_inames_conditional_generation_avoids_irrelevant_constraints(ctx_factory):
+    ctx = ctx_factory()
+    knl = lp.make_kernel(
+        "{[i, loc1, loc2]: 0 <= loc1 <= 1 and 0 <= loc2 <= 2"
+        " and 0 <= i <= loc1 and 0 <= i <= loc2}",
+        """
+        <>tmp[loc2] = 0
+
+        for i
+          tmp[i] = 1 {inames=i:loc2}
+        end
+
+        out[loc2] = tmp[loc2]
+        """,
+        "...",
+        seq_dependencies=True)
+
+    knl = lp.tag_inames(knl, dict(loc1="l.0", loc2="l.0"))
+    knl = lp.set_temporary_scope(knl, "tmp", "local")
+
+    with cl.CommandQueue(ctx) as queue:
+        evt, (out,) = knl(queue)
+
+    assert all(out.get() == 1)
+
+
 def test_kernel_var_name_generator():
     knl = lp.make_kernel(
             "{[i]: 0 <= i <= 10}",
-- 
GitLab


From 442149e693961275471f07331ec1ab4ee6994520 Mon Sep 17 00:00:00 2001
From: Matt Wala <wala1@illinois.edu>
Date: Fri, 9 Jun 2017 23:37:17 -0500
Subject: [PATCH 2/2] Bump kernel version for
 8eb5aa1890248485b160794b47656ebcc8148b31

---
 loopy/version.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/loopy/version.py b/loopy/version.py
index 8516ce006..02244f55d 100644
--- a/loopy/version.py
+++ b/loopy/version.py
@@ -32,4 +32,4 @@ except ImportError:
 else:
     _islpy_version = islpy.version.VERSION_TEXT
 
-DATA_MODEL_VERSION = "v63-islpy%s" % _islpy_version
+DATA_MODEL_VERSION = "v64-islpy%s" % _islpy_version
-- 
GitLab