[PATCH v2 1/3] vkd3d-shader/ir: Swap selection branches if the if branch is empty.

[Giovanni Mascellani]

From: Giovanni Mascellani

---
 libs/vkd3d-shader/ir.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/libs/vkd3d-shader/ir.c b/libs/vkd3d-shader/ir.c
index 610d907d9..b0b3499c2 100644
--- a/libs/vkd3d-shader/ir.c
+++ b/libs/vkd3d-shader/ir.c
@@ -4268,6 +4268,17 @@ static enum vkd3d_result vsir_cfg_move_breaks_out_of_selections(struct vsir_cfg
         --cfg->loop_intervals[else_target].target_count;
     }

+    /* If a branch becomes empty, make it the else branch, so we save a block. */
+    if (selection->u.selection.if_body.count == 0)
+    {
+        struct vsir_cfg_structure_list tmp;
+
+        selection->u.selection.invert_condition = !selection->u.selection.invert_condition;
+        tmp = selection->u.selection.if_body;
+        selection->u.selection.if_body = selection->u.selection.else_body;
+        selection->u.selection.else_body = tmp;
+    }
+
     return VKD3D_OK;
 }