st/mesa: do not init limits when compute shaders are not supported

When the number of uniform blocks is less than 12,
ARB_uniform_buffer_object can't be enabled and the maximum GL version
is not even 3.1...

This fixes a regression introduced in 7c79c1e (st/mesa: add compute
shader state) if the maximum number of uniform blocks allowed for
compute shaders is less than 12. This happens on Kepler but this might
also affect other Gallium drivers.

Signed-off-by: Samuel Pitoiset <[email protected]>
Reported-by: Tobias Klausmann <[email protected]>
Tested-by: Tobias Klausmann <[email protected]>
Reviewed-by: Ilia Mirkin <[email protected]>
Reviewed-by: Tobias Klausmann <[email protected]>

1 files changed, 8 insertions, 0 deletions

diff --git a/src/mesa/state_tracker/st_extensions.c b/src/mesa/state_tracker/st_extensions.c
index 9077added7c..24c64447f44 100644
--- a/src/mesa/state_tracker/st_extensions.c
+++ b/src/mesa/state_tracker/st_extensions.c
@@ -75,6 +75,7 @@ static int _clamp(int a, int min, int max)
 void st_init_limits(struct pipe_screen *screen,
                     struct gl_constants *c, struct gl_extensions *extensions)
 {
+   int supported_irs;
    unsigned sh;
    boolean can_ubo = TRUE;
 
@@ -177,6 +178,13 @@ void st_init_limits(struct pipe_screen *screen,
       case PIPE_SHADER_COMPUTE:
          pc = &c->Program[MESA_SHADER_COMPUTE];
          options = &c->ShaderCompilerOptions[MESA_SHADER_COMPUTE];
+
+         if (!screen->get_param(screen, PIPE_CAP_COMPUTE))
+            continue;
+         supported_irs =
+            screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_SUPPORTED_IRS);
+         if (!(supported_irs & (1 << PIPE_SHADER_IR_TGSI)))
+            continue;
          break;
       default:
          assert(0);