compiler: Move double_inputs to gl_program::DualSlotInputs

Previously, we had two field in shader_info: double_inputs_read and
double_inputs.  Presumably, the one was for all double inputs that are
read and the other is all that exist.  However, because nir_gather_info
regenerates these two values, there is a possibility, if a variable gets
deleted, that the value of double_inputs could change over time.  This
is a problem because double_inputs is used to remap the input locations
to a two-slot-per-dvec3/4 scheme for i965.  If that mapping were to
change between glsl_to_nir and back-end state setup, we would fall over
when trying to map the NIR outputs back onto the GL location space.

This commit changes the way slot re-mapping works.  Instead of the
double_inputs field in shader_info, it adds a DualSlotInputs bitfield to
gl_program.  By having it in gl_program, we more easily guarantee that
NIR passes won't touch it after it's been set.  It also makes more sense
to put it in a GL data structure since it's really a mapping from GL
slots to back-end and/or NIR slots and not really a NIR shader thing.

Tested-by: Alejandro Piñeiro <[email protected]> (ARB_gl_spirv tests)
Reviewed-by: Alejandro Piñeiro <[email protected]>
Reviewed-by: Timothy Arceri <[email protected]>

1 files changed, 5 insertions, 11 deletions

diff --git a/src/compiler/glsl/glsl_to_nir.cpp b/src/compiler/glsl/glsl_to_nir.cpp
index f38d280d406..d22f4a58dd4 100644
--- a/src/compiler/glsl/glsl_to_nir.cpp
+++ b/src/compiler/glsl/glsl_to_nir.cpp
@@ -149,8 +149,11 @@ glsl_to_nir(const struct gl_shader_program *shader_prog,
     * two locations. For instance, if we have in the IR code a dvec3 attr0 in
     * location 0 and vec4 attr1 in location 1, in NIR attr0 will use
     * locations/slots 0 and 1, and attr1 will use location/slot 2 */
-   if (shader->info.stage == MESA_SHADER_VERTEX)
-      nir_remap_attributes(shader, options);
+   if (shader->info.stage == MESA_SHADER_VERTEX) {
+      sh->Program->DualSlotInputs = nir_get_dual_slot_attributes(shader);
+      if (options->vs_inputs_dual_locations)
+         nir_remap_dual_slot_attributes(shader, sh->Program->DualSlotInputs);
+   }
 
    shader->info.name = ralloc_asprintf(shader, "GLSL%d", shader_prog->Name);
    if (shader_prog->Label)
@@ -344,15 +347,6 @@ nir_visitor::visit(ir_variable *ir)
             var->data.compact = ir->type->without_array()->is_scalar();
          }
       }
-
-      /* Mark all the locations that require two slots */
-      if (shader->info.stage == MESA_SHADER_VERTEX &&
-          glsl_type_is_dual_slot(glsl_without_array(var->type))) {
-         for (unsigned i = 0; i < glsl_count_attribute_slots(var->type, true); i++) {
-            uint64_t bitfield = BITFIELD64_BIT(var->data.location + i);
-            shader->info.vs.double_inputs |= bitfield;
-         }
-      }
       break;
 
    case ir_var_shader_out: