st/mesa: expose EXT_gpu_shader4 if GLSL 1.40 is supported

Tested-by: Dieter Nützel <Dieter@nuetzel-hh.de>
Reviewed-by: Eric Anholt <eric@anholt.net>

docs/relnotes/19.1.0.html

@@ -40,7 +40,9 @@ TBD.
 
 <ul>
 <li>GL_ARB_parallel_shader_compile on all drivers.</li>
+<li>GL_EXT_gpu_shader4 on all GL 3.1 drivers.</li>
 <li>GL_EXT_shader_image_load_formatted on radeonsi.</li>
+<li>GL_EXT_texture_buffer_object on all GL 3.1 drivers.</li>
 <li>GL_EXT_texture_compression_s3tc_srgb on Gallium drivers and i965 (ES extension).</li>
 <li>GL_NV_compute_shader_derivatives on iris and i965.</li>
 <li>GL_KHR_parallel_shader_compile on all drivers.</li>

src/mesa/state_tracker/st_extensions.c

@@ -1107,6 +1107,13 @@ void st_init_extensions(struct pipe_screen *screen,
    }
 
    if (GLSLVersion >= 140) {
+      /* Since GLSL 1.40 has support for all of the features of gpu_shader4,
+       * we can always expose it if the driver can do 140. Supporting
+       * gpu_shader4 on drivers without GLSL 1.40 is left for a future
+       * pipe cap.
+       */
+      extensions->EXT_gpu_shader4 = GL_TRUE;
+
       if (screen->get_param(screen, PIPE_CAP_TGSI_ARRAY_COMPONENTS))
          extensions->ARB_enhanced_layouts = GL_TRUE;
    }