From e05cb967e7443d0eca5090537ad0a0902e7ec1d6 Mon Sep 17 00:00:00 2001
From: Faith Ekstrand <faith.ekstrand@collabora.com>
Date: Sat, 25 May 2024 08:09:43 -0500
Subject: [PATCH] nir: Add nir_foreach_block_in_cf_node_safe() iterators

Reviewed-by: Karol Herbst <kherbst@redhat.com>
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/29591>
---
 src/compiler/nir/nir.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/compiler/nir/nir.h b/src/compiler/nir/nir.h
index 6201f9f8154..76f2ab8abd5 100644
--- a/src/compiler/nir/nir.h
+++ b/src/compiler/nir/nir.h
@@ -4939,11 +4939,23 @@ nir_block *nir_cf_node_cf_tree_prev(nir_cf_node *node);
         block != nir_cf_node_cf_tree_next(node);            \
         block = nir_block_cf_tree_next(block))
 
+#define nir_foreach_block_in_cf_node_safe(block, node)      \
+   for (nir_block *block = nir_cf_node_cf_tree_first(node), \
+                  *next = nir_block_cf_tree_next(block);    \
+        block != nir_cf_node_cf_tree_next(node);            \
+        block = next, next = nir_block_cf_tree_next(block))
+
 #define nir_foreach_block_in_cf_node_reverse(block, node)  \
    for (nir_block *block = nir_cf_node_cf_tree_last(node); \
         block != nir_cf_node_cf_tree_prev(node);           \
         block = nir_block_cf_tree_prev(block))
 
+#define nir_foreach_block_in_cf_node_reverse_safe(block, node) \
+   for (nir_block *block = nir_cf_node_cf_tree_last(node),     \
+                  *prev = nir_block_cf_tree_prev(block);       \
+        block != nir_cf_node_cf_tree_prev(node);               \
+        block = prev, prev = nir_block_cf_tree_prev(block))
+
 /* If the following CF node is an if, this function returns that if.
  * Otherwise, it returns NULL.
  */