Francisco Casas : vkd3d-shader/tpf: Avoid reading constant value components beyond type's width (Valgrind).

[Alexandre Julliard]

Module: vkd3d
Branch: master
Commit: ed9e236b0173e89265453b6bc993fdce47ea7122
URL:    https://gitlab.winehq.org/wine/vkd3d/-/commit/ed9e236b0173e89265453b6bc993fd...

Author: Francisco Casas 
Date:   Tue Aug 22 03:40:50 2023 -0400

vkd3d-shader/tpf: Avoid reading constant value components beyond type's width (Valgrind).

We are passing map writemasks that may have more components than the
constant's data type, so a (j < width) check is added to avoid reading
components from the constant that are not intended to be used.

Remaining values in the register are initialized to zero.

---

libs/vkd3d-shader/tpf.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/libs/vkd3d-shader/tpf.c b/libs/vkd3d-shader/tpf.c
index 550f9b27..cf2cc0d1 100644
--- a/libs/vkd3d-shader/tpf.c
+++ b/libs/vkd3d-shader/tpf.c
@@ -3715,8 +3715,10 @@ static void sm4_src_from_constant_value(struct sm4_src_register *src,
         src->reg.dim = VKD3D_SM4_DIMENSION_VEC4;
         for (i = 0; i < 4; ++i)
         {
-            if (map_writemask & (1u << i))
+            if ((map_writemask & (1u << i)) && (j < width))
                 src->reg.immconst_uint[i] = value->u[j++].u;
+            else
+                src->reg.immconst_uint[i] = 0;
         }
     }
 }