i965/fs: Simplify computation of key.input_slots_valid during precompile.

The for loop was rather silly.  In addition to checking brw->gen < 6
on each loop iteration, it took pains to exclude bits from
fp->Base.InputsRead that don't correspond to fragment shader inputs.
But those bits would never have been set in the first place, since the
only bits that are ever set in fp->Base.InputsRead are fragment shader
inputs.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>

diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp
index 9cb79506326d294ab22dde6c505295ea4683e9cd..004b3b55a2ba445fb208dbc0400b09497ba4e9f8 100644 (file)
--- a/src/mesa/drivers/dri/i965/brw_fs.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs.cpp
@@ -3150,17 +3150,7 @@ brw_fs_precompile(struct gl_context *ctx, struct gl_shader_program *prog)
    }
 
    if (brw->gen < 6)
-      key.input_slots_valid |= BITFIELD64_BIT(VARYING_SLOT_POS);
-
-   for (int i = 0; i < VARYING_SLOT_MAX; i++) {
-      if (!(fp->Base.InputsRead & BITFIELD64_BIT(i)))
-        continue;
-
-      if (brw->gen < 6) {
-         if (_mesa_varying_slot_in_fs((gl_varying_slot) i))
-            key.input_slots_valid |= BITFIELD64_BIT(i);
-      }
-   }
+      key.input_slots_valid = fp->Base.InputsRead | VARYING_BIT_POS;
 
    key.clamp_fragment_color = ctx->API == API_OPENGL_COMPAT;