diff --git a/libs/vkd3d-shader/spirv.c b/libs/vkd3d-shader/spirv.c
index 64d4e8a79a60189e7659fa97e924ae82a951a67b..0e75b0ae139acd63431d8e471cfa357219322977 100644
--- a/libs/vkd3d-shader/spirv.c
+++ b/libs/vkd3d-shader/spirv.c
@@ -9023,10 +9023,15 @@ static void vkd3d_dxbc_compiler_emit_hull_shader_inputs(struct vkd3d_dxbc_compil
 
         symbol.key.reg.idx = register_idx;
         if ((entry = rb_get(&compiler->symbol_table, &symbol)))
+        {
+            struct vkd3d_symbol *s = RB_ENTRY_VALUE(entry, struct vkd3d_symbol, entry);
+            s->info.reg.dcl_mask |= signature->elements[i].mask;
             continue;
+        }
 
         vkd3d_symbol_set_register_info(&symbol, vicp_id, SpvStorageClassPrivate,
                 VKD3D_SHADER_COMPONENT_FLOAT, VKD3DSP_WRITEMASK_ALL);
+        symbol.info.reg.dcl_mask = signature->elements[i].mask;
         symbol.info.reg.is_aggregate = true;
         vkd3d_dxbc_compiler_put_symbol(compiler, &symbol);
     }