[Piglit] [PATCH 61/63] shader_runner/spirv: add check for SPV extension support

[Alejandro Piñeiro]

This only affects the case where SPIR-V shaders are run, specially
when using tests coming from other extensions.

In several cases, OpenGL supports an extension with a given
functionality. And such functionality it is not supported on core
SPIR-V but on a equivalent SPV functionality.

But it is not mandatory to support such SPV extension even if you
support the equivalent OpenGL one.

So for that case, we need to check for the equivalent SPV extension
and check if it is supported.
---
 tests/shaders/shader_runner.c | 82 ++++++++++++++++++++++++++++++++++-
 1 file changed, 80 insertions(+), 2 deletions(-)

diff --git a/tests/shaders/shader_runner.c b/tests/shaders/shader_runner.c
index 33b2fe6df..796a61178 100644
--- a/tests/shaders/shader_runner.c
+++ b/tests/shaders/shader_runner.c
@@ -1041,6 +1041,84 @@ parse_version_comparison(const char *line, enum comparison *cmp,
 	version_init(v, tag, core, compat, es, full_num);
 }
 
+#define KNOWN_GL_SPV_MAPPING 3
+
+static const char* table[KNOWN_GL_SPV_MAPPING][2] =
+{{ "GL_AMD_shader_trinary_minmax", "SPV_AMD_shader_trinary_minmax"},
+ {"GL_ARB_shader_group_vote", "SPV_KHR_subgroup_vote"},
+ {"GL_ARB_shader_ballot", "SPV_KHR_shader_ballot"}};
+
+/*
+ * Returns the SPIR-V extension that defines the equivalent
+ * funcionality provided by the OpenGL extension @gl_name
+ */
+static const char *
+check_spv_extension_equivalent(const char *gl_name)
+{
+        unsigned int i;
+
+        for (i = 0 ; i < KNOWN_GL_SPV_MAPPING; i++)
+                if (strcmp(gl_name, table[i][0]) == 0)
+                        return table[i][1];
+
+	return NULL;
+}
+
+
+/* Perhaps we could move this to piglit-util. For now it is only used
+ * on shader_runner
+ */
+static const char **spirv_extensions = NULL;
+
+static void
+initialize_spv_extensions(void)
+{
+	int loop, num_spir_v_extensions;
+
+	if (spirv_extensions != NULL)
+		return;
+
+	glGetIntegerv(GL_NUM_SPIR_V_EXTENSIONS, &num_spir_v_extensions);
+	spirv_extensions = malloc (sizeof(char*) * (num_spir_v_extensions + 1));
+	assert (spirv_extensions != NULL);
+
+	for (loop = 0; loop < num_spir_v_extensions; loop++) {
+		spirv_extensions[loop] = (const char*) glGetStringi(GL_SPIR_V_EXTENSIONS, loop);
+	}
+
+	spirv_extensions[loop] = NULL;
+}
+
+static bool
+spv_is_extension_supported(const char *name)
+{
+	initialize_spv_extensions();
+	return piglit_is_extension_in_array(spirv_extensions, name);
+}
+
+/*
+ * Wrapper for extension checking.  If using a GLSL shader, this
+ * method is equivalent to call piglit_is_extension_supported.
+ *
+ * But with SPIR-V shaders we can't just check for the OpenGL
+ * extension, but also for the SPV equivalent if using a SPIR-V
+ * binary, as it is not mandatory to support the SPV extension even if
+ * the equivalent OpenGL one is.
+ */
+static bool
+shader_runner_is_extension_supported(const char *name)
+{
+	bool result = true;
+	if (spirv_replaces_glsl) {
+		const char *spv_name = check_spv_extension_equivalent(name);
+
+		if (spv_name != NULL)
+			result = result && spv_is_extension_supported(spv_name);
+	}
+
+	return result && piglit_is_extension_supported(name);
+}
+
 /**
  * Parse and check a line from the requirement section of the test
  */
@@ -1161,12 +1239,12 @@ process_requirement(const char *line)
 
 	if (parse_str(line, "GL_", NULL) &&
 	    parse_word_copy(line, buffer, sizeof(buffer), &line)) {
-		if (!piglit_is_extension_supported(buffer))
+		if (!shader_runner_is_extension_supported(buffer))
 			return PIGLIT_SKIP;
 	} else if (parse_str(line, "!", &line) &&
 		   parse_str(line, "GL_", NULL) &&
 		   parse_word_copy(line, buffer, sizeof(buffer), &line)) {
-		if (piglit_is_extension_supported(buffer))
+		if (shader_runner_is_extension_supported(buffer))
 			return PIGLIT_SKIP;
 	} else if (parse_str(line, "GLSL", &line)) {
 		enum comparison cmp;
-- 
2.19.1