[Mesa-dev] [PATCH 14/18] nir/glsl: add double packing support to vs and fs

[Timothy Arceri]

---
 src/compiler/glsl/link_varyings.cpp | 16 +++++++++++++---
 src/compiler/nir/nir_lower_io.c     | 16 ++++++++++++++++
 2 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/src/compiler/glsl/link_varyings.cpp b/src/compiler/glsl/link_varyings.cpp
index 22dc2d8..7c0d93a 100644
--- a/src/compiler/glsl/link_varyings.cpp
+++ b/src/compiler/glsl/link_varyings.cpp
@@ -1992,10 +1992,11 @@ set_num_packed_components(struct gl_shader *shader, ir_variable_mode io_mode,
           var->type->without_array()->is_matrix())
          continue;
 
+      unsigned dfrac = var->type->without_array()->is_double() ? 2 : 1;
       if (var->type->is_array()) {
          const glsl_type *type = get_varying_type(var, shader->Stage);
          unsigned array_components = type->without_array()->vector_elements +
-            var->data.location_frac;
+            var->data.location_frac / dfrac;
          assert(type->arrays_of_arrays_size() + idx <=
                 ARRAY_SIZE(num_components));
          for (unsigned i = idx; i < type->arrays_of_arrays_size(); i++) {
@@ -2003,7 +2004,7 @@ set_num_packed_components(struct gl_shader *shader, ir_variable_mode io_mode,
          }
       } else {
          unsigned comps = var->type->vector_elements +
-            var->data.location_frac;
+            var->data.location_frac / dfrac;
          num_components[idx] = MAX2(comps, num_components[idx]);
       }
    }
@@ -2031,7 +2032,16 @@ set_num_packed_components(struct gl_shader *shader, ir_variable_mode io_mode,
             c = MAX2(c, num_components[i]);
          }
       } else {
-         c = num_components[idx];
+         /* Handle special case of packing dvec3 with a double. The only
+          * valid scenario is packing a double in the 4th component of the
+          * double vector.
+          */
+         if (var->type->is_double() && var->type->vector_elements == 3 &&
+             num_components[idx+1] == 2) {
+            c = 4;
+         } else {
+            c = num_components[idx];
+         }
       }
       var->data.num_packed_components = c;
    }
diff --git a/src/compiler/nir/nir_lower_io.c b/src/compiler/nir/nir_lower_io.c
index b966348..5566c83 100644
--- a/src/compiler/nir/nir_lower_io.c
+++ b/src/compiler/nir/nir_lower_io.c
@@ -104,6 +104,22 @@ nir_assign_var_locations(struct exec_list *var_list, unsigned *size,
          if (locations[idx][var->data.index] == -1) {
             var->data.driver_location = location;
             locations[idx][var->data.index] = location;
+
+            /* A dvec3 can be packed with a double we need special handling
+             * for this as we are packing across two locations.
+             */
+            if (glsl_get_base_type(var->type) == GLSL_TYPE_DOUBLE &&
+                glsl_get_vector_elements(var->type) == 3) {
+               /* Hack around type_size functions that expect vectors to be
+                * padded out to vec4.
+                */
+               unsigned dsize = type_size(glsl_double_type());
+               unsigned offset =
+                  dsize == type_size(glsl_float_type()) ? dsize : dsize * 2;
+
+               locations[idx + 1][var->data.index] = location + offset;
+            }
+
             location += type_size(var->type) +
                calc_type_size_offset(var->data.num_packed_components,
                                      var->type, type_size);
-- 
2.5.5