nir: Remove some unused fields from nir_variable

All of these are happily set from glsl_to_nir or spirv_to_nir but their
values are never used for anything.

Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>

src/compiler/glsl/glsl_to_nir.cpp

@@ -340,10 +340,6 @@ nir_visitor::visit(ir_variable *ir)
    var->data.interpolation = ir->data.interpolation;
    var->data.origin_upper_left = ir->data.origin_upper_left;
    var->data.pixel_center_integer = ir->data.pixel_center_integer;
-   var->data.explicit_location = ir->data.explicit_location;
-   var->data.explicit_index = ir->data.explicit_index;
-   var->data.explicit_binding = ir->data.explicit_binding;
-   var->data.has_initializer = ir->data.has_initializer;
    var->data.compact = false;
    var->data.location_frac = ir->data.location_frac;
 
@@ -376,7 +372,6 @@ nir_visitor::visit(ir_variable *ir)
    var->data.image._volatile = ir->data.image_volatile;
    var->data.image.restrict_flag = ir->data.image_restrict;
    var->data.image.format = ir->data.image_format;
-   var->data.max_array_access = ir->data.max_array_access;
    var->data.fb_fetch_output = ir->data.fb_fetch_output;
 
    var->num_state_slots = ir->get_num_state_slots();

src/compiler/nir/nir.h

@@ -193,32 +193,6 @@ typedef struct nir_variable {
       unsigned pixel_center_integer:1;
       /*@}*/
 
-      /**
-       * Was the location explicitly set in the shader?
-       *
-       * If the location is explicitly set in the shader, it \b cannot be changed
-       * by the linker or by the API (e.g., calls to \c glBindAttribLocation have
-       * no effect).
-       */
-      unsigned explicit_location:1;
-      unsigned explicit_index:1;
-
-      /**
-       * Was an initial binding explicitly set in the shader?
-       *
-       * If so, constant_initializer contains an integer nir_constant
-       * representing the initial binding point.
-       */
-      unsigned explicit_binding:1;
-
-      /**
-       * Does this variable have an initializer?
-       *
-       * This is used by the linker to cross-validiate initializers of global
-       * variables.
-       */
-      unsigned has_initializer:1;
-
       /**
        * If non-zero, then this variable may be packed along with other variables
        * into a single varying slot, so this offset should be applied when
@@ -312,14 +286,6 @@ typedef struct nir_variable {
          /** Image internal format if specified explicitly, otherwise GL_NONE. */
          GLenum format;
       } image;
-
-      /**
-       * Highest element accessed with a constant expression array index
-       *
-       * Not used for non-array variables.
-       */
-      unsigned max_array_access;
-
    } data;
 
    /**

src/compiler/spirv/vtn_variables.c

@@ -931,7 +931,6 @@ apply_var_decoration(struct vtn_builder *b, nir_variable *nir_var,
       nir_var->data.location_frac = dec->literals[0];
       break;
    case SpvDecorationIndex:
-      nir_var->data.explicit_index = true;
       nir_var->data.index = dec->literals[0];
       break;
    case SpvDecorationBuiltIn: {
@@ -952,7 +951,6 @@ apply_var_decoration(struct vtn_builder *b, nir_variable *nir_var,
 
       nir_variable_mode mode = nir_var->data.mode;
       vtn_get_builtin_location(b, builtin, &nir_var->data.location, &mode);
-      nir_var->data.explicit_location = true;
       nir_var->data.mode = mode;
 
       if (builtin == SpvBuiltInFragCoord || builtin == SpvBuiltInSamplePosition)
@@ -1073,7 +1071,6 @@ var_decoration_cb(struct vtn_builder *b, struct vtn_value *val, int member,
       if (vtn_var->var) {
          /* This handles the member and lone variable cases */
          vtn_var->var->data.location = location;
-         vtn_var->var->data.explicit_location = true;
       } else {
          /* This handles the structure member case */
          assert(vtn_var->members);
@@ -1081,7 +1078,6 @@ var_decoration_cb(struct vtn_builder *b, struct vtn_value *val, int member,
             glsl_get_length(glsl_without_array(vtn_var->type->type));
          for (unsigned i = 0; i < length; i++) {
             vtn_var->members[i]->data.location = location;
-            vtn_var->members[i]->data.explicit_location = true;
             location +=
                glsl_count_attribute_slots(vtn_var->members[i]->interface_type,
                                           is_vertex_input);