Mesa (staging/21.2): glsl: fix explicit-location ifc matching in presence of array types

[GitLab Mirror]

Module: Mesa
Branch: staging/21.2
Commit: 18581c3a30f33694c29681f205e8878a5e405b94
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=18581c3a30f33694c29681f205e8878a5e405b94

Author: Ilia Mirkin <imirkin at alum.mit.edu>
Date:   Thu Aug 19 17:59:18 2021 -0400

glsl: fix explicit-location ifc matching in presence of array types

We were treating each field as if it took up a single slot. However
that's not the case. And with strict matching (GLSL 4.20+ / ES 3.1+) we
would end up not matching identical interfaces.

Fixes: c4545676d7 ("glsl/linker: fix location aliasing checks for interface variables")
Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
Reviewed-by: Timothy Arceri <tarceri at itsqueeze.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/12479>
(cherry picked from commit 18962b94d31d82ae0a697c2afb731f4a447e1b54)

---

 .pick_status.json                   | 2 +-
 src/compiler/glsl/link_varyings.cpp | 4 +++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/.pick_status.json b/.pick_status.json
index 8fe665a2b9e..139cb6a71f1 100644
--- a/.pick_status.json
+++ b/.pick_status.json
@@ -832,7 +832,7 @@
         "description": "glsl: fix explicit-location ifc matching in presence of array types",
         "nominated": true,
         "nomination_type": 1,
-        "resolution": 0,
+        "resolution": 1,
         "main_sha": null,
         "because_sha": "c4545676d7f4e5f898bdc54d5574cd56ca7b9aad"
     },
diff --git a/src/compiler/glsl/link_varyings.cpp b/src/compiler/glsl/link_varyings.cpp
index 9954a731479..997513a636d 100644
--- a/src/compiler/glsl/link_varyings.cpp
+++ b/src/compiler/glsl/link_varyings.cpp
@@ -660,9 +660,11 @@ validate_explicit_variable_location(struct gl_context *ctx,
          glsl_struct_field *field = &type_without_array->fields.structure[i];
          unsigned field_location = field->location -
             (field->patch ? VARYING_SLOT_PATCH0 : VARYING_SLOT_VAR0);
+         unsigned field_slots = field->type->count_attribute_slots(false);
          if (!check_location_aliasing(explicit_locations, var,
                                       field_location,
-                                      0, field_location + 1,
+                                      0,
+                                      field_location + field_slots,
                                       field->type,
                                       field->interpolation,
                                       field->centroid,