vc4: Fix handling of sample_mask output.

I apparently broke this in a late refactor, in such a way that I decided
its tests were some of those interminable ones that I should just
blacklist from my testing.  As a result, the refactors related to it were
totally wrong.

1 files changed, 4 insertions, 5 deletions

diff --git a/src/gallium/drivers/vc4/vc4_nir_lower_blend.c b/src/gallium/drivers/vc4/vc4_nir_lower_blend.c
index 4b10cb7fe56..a1ec4c70918 100644
--- a/src/gallium/drivers/vc4/vc4_nir_lower_blend.c
+++ b/src/gallium/drivers/vc4/vc4_nir_lower_blend.c
@@ -589,10 +589,10 @@ vc4_nir_next_output_driver_location(nir_shader *s)
 {
         int maxloc = -1;
 
-        nir_foreach_variable(var, &s->inputs)
-                maxloc = MAX2(maxloc, var->data.driver_location);
+        nir_foreach_variable(var, &s->outputs)
+                maxloc = MAX2(maxloc, (int)var->data.driver_location);
 
-        return maxloc;
+        return maxloc + 1;
 }
 
 static void
@@ -605,12 +605,11 @@ vc4_nir_store_sample_mask(struct vc4_compile *c, nir_builder *b,
         sample_mask->data.driver_location =
                 vc4_nir_next_output_driver_location(c->s);
         sample_mask->data.location = FRAG_RESULT_SAMPLE_MASK;
-        exec_list_push_tail(&c->s->outputs, &sample_mask->node);
 
         nir_intrinsic_instr *intr =
                 nir_intrinsic_instr_create(c->s, nir_intrinsic_store_output);
         intr->num_components = 1;
-        intr->const_index[0] = sample_mask->data.location;
+        intr->const_index[0] = sample_mask->data.driver_location;
 
         intr->src[0] = nir_src_for_ssa(val);
         intr->src[1] = nir_src_for_ssa(nir_imm_int(b, 0));