nir: Add test file for vars related passes

Add basic helpers for doing tests on the vars related optimization
passes.  The main goal is to lower the barrier to create tests during
development and debugging of the passes.  Full coverage is not a
requirement.

v2: Make find_next_intrinsic() skip blocks before 'after'. (Jason)
    Move nir_imm_ivec2() to nir_builder.h. (Jason)

Reviewed-by: Jason Ekstrand <[email protected]>

2 files changed, 201 insertions, 0 deletions

diff --git a/src/compiler/nir/meson.build b/src/compiler/nir/meson.build
index 090aa7a628f..1a7fa2d3327 100644
--- a/src/compiler/nir/meson.build
+++ b/src/compiler/nir/meson.build
@@ -245,4 +245,15 @@ if with_tests
       link_with : libmesa_util,
     )
   )
+  test(
+    'nir_vars',
+    executable(
+      'nir_vars_test',
+      files('tests/vars_tests.cpp'),
+      cpp_args : [cpp_vis_args, cpp_msvc_compat_args],
+      include_directories : [inc_common],
+      dependencies : [dep_thread, idep_gtest, idep_nir],
+      link_with : libmesa_util,
+    )
+  )
 endif
diff --git a/src/compiler/nir/tests/vars_tests.cpp b/src/compiler/nir/tests/vars_tests.cpp
new file mode 100644
index 00000000000..9b2877fcc92
--- /dev/null
+++ b/src/compiler/nir/tests/vars_tests.cpp
@@ -0,0 +1,190 @@
+/*
+ * Copyright © 2018 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#include <gtest/gtest.h>
+
+#include "nir.h"
+#include "nir_builder.h"
+
+namespace {
+
+class nir_vars_test : public ::testing::Test {
+protected:
+   nir_vars_test();
+   ~nir_vars_test();
+
+   nir_variable *create_int(nir_variable_mode mode, const char *name) {
+      if (mode == nir_var_local)
+         return nir_local_variable_create(b->impl, glsl_int_type(), name);
+      return nir_variable_create(b->shader, mode, glsl_int_type(), name);
+   }
+
+   nir_variable *create_ivec2(nir_variable_mode mode, const char *name) {
+      const glsl_type *var_type = glsl_vector_type(GLSL_TYPE_INT, 2);
+      if (mode == nir_var_local)
+         return nir_local_variable_create(b->impl, var_type, name);
+      return nir_variable_create(b->shader, mode, var_type, name);
+   }
+
+   nir_variable **create_many_int(nir_variable_mode mode, const char *prefix, unsigned count) {
+      nir_variable **result = (nir_variable **)linear_alloc_child(lin_ctx, sizeof(nir_variable *) * count);
+      for (unsigned i = 0; i < count; i++)
+         result[i] = create_int(mode, linear_asprintf(lin_ctx, "%s%u", prefix, i));
+      return result;
+   }
+
+   nir_variable **create_many_ivec2(nir_variable_mode mode, const char *prefix, unsigned count) {
+      nir_variable **result = (nir_variable **)linear_alloc_child(lin_ctx, sizeof(nir_variable *) * count);
+      for (unsigned i = 0; i < count; i++)
+         result[i] = create_ivec2(mode, linear_asprintf(lin_ctx, "%s%u", prefix, i));
+      return result;
+   }
+
+   unsigned count_intrinsics(nir_intrinsic_op intrinsic);
+
+   nir_intrinsic_instr *find_next_intrinsic(nir_intrinsic_op intrinsic,
+                                            nir_intrinsic_instr *after);
+
+   void *mem_ctx;
+   void *lin_ctx;
+
+   nir_builder *b;
+};
+
+nir_vars_test::nir_vars_test()
+{
+   mem_ctx = ralloc_context(NULL);
+   lin_ctx = linear_alloc_parent(mem_ctx, 0);
+   static const nir_shader_compiler_options options = { };
+   b = rzalloc(mem_ctx, nir_builder);
+   nir_builder_init_simple_shader(b, mem_ctx, MESA_SHADER_FRAGMENT, &options);
+}
+
+nir_vars_test::~nir_vars_test()
+{
+   if (HasFailure()) {
+      printf("\nShader from the failed test:\n\n");
+      nir_print_shader(b->shader, stdout);
+   }
+
+   ralloc_free(mem_ctx);
+}
+
+unsigned
+nir_vars_test::count_intrinsics(nir_intrinsic_op intrinsic)
+{
+   unsigned count = 0;
+   nir_foreach_block(block, b->impl) {
+      nir_foreach_instr(instr, block) {
+         if (instr->type != nir_instr_type_intrinsic)
+            continue;
+         nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
+         if (intrin->intrinsic == intrinsic)
+            count++;
+      }
+   }
+   return count;
+}
+
+nir_intrinsic_instr *
+nir_vars_test::find_next_intrinsic(nir_intrinsic_op intrinsic,
+                                   nir_intrinsic_instr *after)
+{
+   bool seen = after == NULL;
+   nir_foreach_block(block, b->impl) {
+      /* Skip blocks before the 'after' instruction. */
+      if (!seen && block != after->instr.block)
+         continue;
+      nir_foreach_instr(instr, block) {
+         if (instr->type != nir_instr_type_intrinsic)
+            continue;
+         nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
+         if (!seen) {
+            seen = (after == intrin);
+            continue;
+         }
+         if (intrin->intrinsic == intrinsic)
+            return intrin;
+      }
+   }
+   return NULL;
+}
+
+/* Allow grouping the tests while still sharing the helpers. */
+class nir_copy_prop_vars_test : public nir_vars_test {};
+
+} // namespace
+
+TEST_F(nir_copy_prop_vars_test, simple_copies)
+{
+   nir_variable *in   = create_int(nir_var_shader_in,  "in");
+   nir_variable *temp = create_int(nir_var_local,      "temp");
+   nir_variable *out  = create_int(nir_var_shader_out, "out");
+
+   nir_copy_var(b, temp, in);
+   nir_copy_var(b, out, temp);
+
+   nir_validate_shader(b->shader);
+
+   bool progress = nir_opt_copy_prop_vars(b->shader);
+   EXPECT_TRUE(progress);
+
+   nir_validate_shader(b->shader);
+
+   nir_intrinsic_instr *copy = NULL;
+   copy = find_next_intrinsic(nir_intrinsic_copy_deref, copy);
+   ASSERT_TRUE(copy->src[1].is_ssa);
+   nir_ssa_def *first_src = copy->src[1].ssa;
+
+   copy = find_next_intrinsic(nir_intrinsic_copy_deref, copy);
+   ASSERT_TRUE(copy->src[1].is_ssa);
+   EXPECT_EQ(copy->src[1].ssa, first_src);
+}
+
+TEST_F(nir_copy_prop_vars_test, simple_store_load)
+{
+   nir_variable **v = create_many_ivec2(nir_var_local, "v", 2);
+   unsigned mask = 1 | 2;
+
+   nir_ssa_def *stored_value = nir_imm_ivec2(b, 10, 20);
+   nir_store_var(b, v[0], stored_value, mask);
+
+   nir_ssa_def *read_value = nir_load_var(b, v[0]);
+   nir_store_var(b, v[1], read_value, mask);
+
+   nir_validate_shader(b->shader);
+
+   bool progress = nir_opt_copy_prop_vars(b->shader);
+   EXPECT_TRUE(progress);
+
+   nir_validate_shader(b->shader);
+
+   ASSERT_EQ(count_intrinsics(nir_intrinsic_store_deref), 2);
+
+   nir_intrinsic_instr *store = NULL;
+   for (int i = 0; i < 2; i++) {
+      store = find_next_intrinsic(nir_intrinsic_store_deref, store);
+      ASSERT_TRUE(store->src[1].is_ssa);
+      EXPECT_EQ(store->src[1].ssa, stored_value);
+   }
+}