Assorted fixery to make stencil test pass.

MEMO

@@ -78,7 +78,7 @@ Future ideas
 
 - Check for unordered (no-dependency) writes to the same location
 
-- String instructions?
+- Vanilla C string instructions?
 
 - Barriers for data exchanged via global vars?
 

loopy/__init__.py

@@ -353,6 +353,8 @@ def add_prefetch(kernel, var_name, sweep_inames=[], dim_arg_names=None,
 
     arg = kernel.arg_dict[var_name]
 
+    # {{{ make parameter names and unification template
+
     parameters = []
     for i in range(arg.dimensions):
         based_on = "%s_dim_%d" % (c_name, i)
@@ -371,8 +373,12 @@ def add_prefetch(kernel, var_name, sweep_inames=[], dim_arg_names=None,
     elif len(parameters) == 1:
         uni_template = uni_template[var(parameters[0])]
 
+    # }}}
+
     kernel = extract_subst(kernel, rule_name, uni_template, parameters)
 
+    # {{{ track applied iname rewrites on footprint_subscripts
+
     if footprint_subscripts is not None:
         if not isinstance(footprint_subscripts, (list, tuple)):
             footprint_subscripts = [footprint_subscripts]
@@ -403,6 +409,8 @@ def add_prefetch(kernel, var_name, sweep_inames=[], dim_arg_names=None,
     else:
         subst_use = rule_name
 
+    # }}}
+
     new_kernel = precompute(kernel, subst_use, arg.dtype, sweep_inames,
             new_storage_axis_names=dim_arg_names,
             default_tag=default_tag)

loopy/kernel.py

@@ -1690,14 +1690,14 @@ class SetOperationCacheManager:
         lower_bound_pw_aff = self.dim_min(set, iname_to_dim[iname][1])
         upper_bound_pw_aff = self.dim_max(set, iname_to_dim[iname][1])
 
-        from loopy.isl_helpers import static_max_of_pw_aff, static_min_of_pw_aff
+        from loopy.isl_helpers import static_max_of_pw_aff, static_value_of_pw_aff
         from loopy.symbolic import pw_aff_to_expr
 
         size = pw_aff_to_expr(static_max_of_pw_aff(
                 upper_bound_pw_aff - lower_bound_pw_aff + 1, constants_only=True,
                 context=context))
         base_index = pw_aff_to_expr(
-            static_min_of_pw_aff(lower_bound_pw_aff, constants_only=False,
+            static_value_of_pw_aff(lower_bound_pw_aff, constants_only=False,
                 context=context))
 
         return base_index, size

loopy/reduction.py

@@ -33,7 +33,7 @@ class ScalarReductionOperation(ReductionOperation):
         result = type(self).__name__.replace("ReductionOperation", "").lower()
 
         if self.forced_result_dtype is not None:
-            result = "%s<%s>" % (result, str(self.dtype))
+            result = "%s<%s>" % (result, str(self.forced_result_dtype))
 
         return result
 

test/test_linalg.py

@@ -221,7 +221,7 @@ def test_plain_matrix_mul(ctx_factory):
         kernel_gen = lp.check_kernels(kernel_gen, {})
 
         lp.auto_test_vs_ref(ref_knl, ctx, kernel_gen,
-                op_count=vec_size*2*n**3/1e9, op_label="GFlops/s",
+                op_count=[vec_size*2*n**3/1e9], op_label=["GFlops"],
                 parameters={"n": n}, check_result=check)
 
 
@@ -354,7 +354,7 @@ def test_rank_one(ctx_factory):
         kernel_gen = lp.check_kernels(kernel_gen, dict(n=n))
 
         lp.auto_test_vs_ref(seq_knl, ctx, kernel_gen,
-                op_count=np.dtype(dtype).itemsize*n**2/1e9, op_label="GBytes",
+                op_count=[np.dtype(dtype).itemsize*n**2/1e9], op_label=["GBytes"],
                 parameters={"n": n})
 
 

test/test_loopy.py

@@ -89,39 +89,41 @@ def test_multi_cse(ctx_factory):
 def test_stencil(ctx_factory):
     ctx = ctx_factory()
 
+    # n=32 causes corner case behavior in size calculations for temprorary (a
+    # non-unifiable, two-constant-segments PwAff as the base index)
+
+    n = 256
     knl = lp.make_kernel(ctx.devices[0],
-            "{[i,j]: 0<= i,j < 32}",
+            "{[i,j]: 0<= i,j < %d}" % n,
             [
-                "[i] z[i,j] = -2*a[i,j]"
-                    " + a[i,j-1]"
-                    " + a[i,j+1]"
-                    " + a[i-1,j]"
-                    " + a[i+1,j]"
+                "a_offset(ii, jj) := a[ii+1, jj+1]",
+                "z[i,j] = -2*a_offset(i,j)"
+                    " + a_offset(i,j-1)"
+                    " + a_offset(i,j+1)"
+                    " + a_offset(i-1,j)"
+                    " + a_offset(i+1,j)"
                 ],
             [
-                lp.GlobalArg("a", np.float32, shape=(32,32,)),
-                lp.GlobalArg("z", np.float32, shape=(32,32,))
+                lp.GlobalArg("a", np.float32, shape=(n+2,n+2,)),
+                lp.GlobalArg("z", np.float32, shape=(n+2,n+2,))
                 ])
 
+    ref_knl = knl
 
     def variant_1(knl):
-        knl = lp.add_prefetch(knl, "a", [0, 1])
-        return knl
-
-    def variant_2(knl):
         knl = lp.split_dimension(knl, "i", 16, outer_tag="g.1", inner_tag="l.1")
         knl = lp.split_dimension(knl, "j", 16, outer_tag="g.0", inner_tag="l.0")
         knl = lp.add_prefetch(knl, "a", ["i_inner", "j_inner"])
         return knl
 
-    #for variant in [variant_1, variant_2]:
-    for variant in [variant_2]:
+    for variant in [variant_1]:
         kernel_gen = lp.generate_loop_schedules(variant(knl),
                 loop_priority=["i_outer", "i_inner_0", "j_0"])
         kernel_gen = lp.check_kernels(kernel_gen)
 
-        for knl in kernel_gen:
-            print lp.generate_code(knl)
+        lp.auto_test_vs_ref(ref_knl, ctx, kernel_gen,
+                fills_entire_output=False, print_ref_code=True,
+                op_count=[n*n], op_label=["cells"])