st/mesa: exit the update fragment samplers/textures loops early.

If we have no more enabled samplers and we've reset all the previously
used ones, no need to keep going around this loop.

(just moved some stuff around to clean it up a bit).

Signed-off-by: Dave Airlie <[email protected]>
Reviewed-by: Brian Paul <[email protected]>

1 files changed, 13 insertions, 6 deletions

diff --git a/src/mesa/state_tracker/st_atom_texture.c b/src/mesa/state_tracker/st_atom_texture.c
index d241527cc6a..e8941da8d79 100644
--- a/src/mesa/state_tracker/st_atom_texture.c
+++ b/src/mesa/state_tracker/st_atom_texture.c
@@ -300,24 +300,31 @@ update_fragment_textures(struct st_context *st)
    const struct gl_context *ctx = st->ctx;
    struct gl_fragment_program *fprog = ctx->FragmentProgram._Current;
    GLuint su;
+   int old_max = st->state.num_textures;
+   GLbitfield samplers_used = fprog->Base.SamplersUsed;
 
    st->state.num_textures = 0;
 
    /* loop over sampler units (aka tex image units) */
-   for (su = 0; su < ctx->Const.MaxTextureImageUnits; su++) {
+   for (su = 0; su < ctx->Const.MaxTextureImageUnits; su++, samplers_used >>= 1) {
       struct pipe_sampler_view *sampler_view = NULL;
-      if (fprog->Base.SamplersUsed & (1 << su)) {
+
+      if (samplers_used & 1) {
          GLboolean retval;
          GLuint texUnit;
 
-	 texUnit = fprog->Base.SamplerUnits[su];
+         texUnit = fprog->Base.SamplerUnits[su];
 
-	 retval = update_single_texture(st, &sampler_view, texUnit);
-	 if (retval == GL_FALSE)
-	    continue;
+         retval = update_single_texture(st, &sampler_view, texUnit);
+         if (retval == GL_FALSE)
+            continue;
 
          st->state.num_textures = su + 1;
+      } else if (samplers_used == 0 && su >= old_max) {
+         /* if we've reset all the old views and we have no more new ones */
+         break;
       }
+
       pipe_sampler_view_reference(&st->state.sampler_views[su], sampler_view);
    }