[Mesa-dev] [PATCH] mesa: implement AMD_shader_stencil_export

[Marek Olšák]

It's just an alias of the ARB variant with some GLSL compiler changes.
---
 src/glsl/glsl_parser_extras.cpp |   10 ++++++++++
 src/glsl/glsl_parser_extras.h   |    2 ++
 src/glsl/ir_variable.cpp        |   20 ++++++++++++++++++++
 src/mesa/main/extensions.c      |    1 +
 4 files changed, 33 insertions(+), 0 deletions(-)

diff --git a/src/glsl/glsl_parser_extras.cpp b/src/glsl/glsl_parser_extras.cpp
index 5bb3a6f..18bff88 100644
--- a/src/glsl/glsl_parser_extras.cpp
+++ b/src/glsl/glsl_parser_extras.cpp
@@ -255,6 +255,16 @@ _mesa_glsl_process_extension(const char *name, YYLTYPE *name_locp,
       state->AMD_conservative_depth_enable = (ext_mode != extension_disable);
       state->AMD_conservative_depth_warn = (ext_mode == extension_warn);
       unsupported = !state->extensions->AMD_conservative_depth;
+   } else if (strcmp(name, "GL_AMD_shader_stencil_export") == 0) {
+      state->AMD_shader_stencil_export_enable = (ext_mode != extension_disable);
+      state->AMD_shader_stencil_export_warn = (ext_mode == extension_warn);
+
+      /* This extension is only supported in fragment shaders.
+       * Both the ARB and AMD variants share the same ARB flag
+       * in gl_extensions.
+       */
+      unsupported = (state->target != fragment_shader)
+	 || !state->extensions->ARB_shader_stencil_export;
    } else if (strcmp(name, "GL_OES_texture_3D") == 0 && state->es_shader) {
       state->OES_texture_3D_enable = (ext_mode != extension_disable);
       state->OES_texture_3D_warn = (ext_mode == extension_warn);
diff --git a/src/glsl/glsl_parser_extras.h b/src/glsl/glsl_parser_extras.h
index 6df0e16..f914765 100644
--- a/src/glsl/glsl_parser_extras.h
+++ b/src/glsl/glsl_parser_extras.h
@@ -172,6 +172,8 @@ struct _mesa_glsl_parse_state {
    unsigned ARB_shader_stencil_export_warn:1;
    unsigned AMD_conservative_depth_enable:1;
    unsigned AMD_conservative_depth_warn:1;
+   unsigned AMD_shader_stencil_export_enable:1;
+   unsigned AMD_shader_stencil_export_warn:1;
    unsigned OES_texture_3D_enable:1;
    unsigned OES_texture_3D_warn:1;
    /*@}*/
diff --git a/src/glsl/ir_variable.cpp b/src/glsl/ir_variable.cpp
index f357717..b848769 100644
--- a/src/glsl/ir_variable.cpp
+++ b/src/glsl/ir_variable.cpp
@@ -767,6 +767,22 @@ generate_ARB_shader_stencil_export_variables(exec_list *instructions,
 }
 
 static void
+generate_AMD_shader_stencil_export_variables(exec_list *instructions,
+					     struct _mesa_glsl_parse_state *state,
+					     bool warn)
+{
+   /* gl_FragStencilRefAMD is only available in the fragment shader.
+    */
+   ir_variable *const fd =
+      add_variable(instructions, state->symbols,
+		   "gl_FragStencilRefAMD", glsl_type::int_type,
+		   ir_var_out, FRAG_RESULT_STENCIL);
+
+   if (warn)
+      fd->warn_extension = "GL_AMD_shader_stencil_export";
+}
+
+static void
 generate_120_fs_variables(exec_list *instructions,
 			  struct _mesa_glsl_parse_state *state)
 {
@@ -818,6 +834,10 @@ initialize_fs_variables(exec_list *instructions,
    if (state->ARB_shader_stencil_export_enable)
       generate_ARB_shader_stencil_export_variables(instructions, state,
 						   state->ARB_shader_stencil_export_warn);
+
+   if (state->AMD_shader_stencil_export_enable)
+      generate_AMD_shader_stencil_export_variables(instructions, state,
+						   state->AMD_shader_stencil_export_warn);
 }
 
 void
diff --git a/src/mesa/main/extensions.c b/src/mesa/main/extensions.c
index beec70a..1062cde 100644
--- a/src/mesa/main/extensions.c
+++ b/src/mesa/main/extensions.c
@@ -260,6 +260,7 @@ static const struct extension extension_table[] = {
    { "GL_3DFX_texture_compression_FXT1",           o(TDFX_texture_compression_FXT1),           GL,             1999 },
    { "GL_AMD_conservative_depth",                  o(AMD_conservative_depth),                  GL,             2009 },
    { "GL_AMD_draw_buffers_blend",                  o(ARB_draw_buffers_blend),                  GL,             2009 },
+   { "GL_AMD_shader_stencil_export",               o(ARB_shader_stencil_export),               GL,             2009 },
    { "GL_APPLE_client_storage",                    o(APPLE_client_storage),                    GL,             2002 },
    { "GL_APPLE_object_purgeable",                  o(APPLE_object_purgeable),                  GL,             2006 },
    { "GL_APPLE_packed_pixels",                     o(APPLE_packed_pixels),                     GL,             2002 },
-- 
1.7.4.1