[Mesa-dev] [PATCH 1.5/3] nir: Add a nir_instr_move helper

[Jason Ekstrand]

Removes an instruction from one place and inserts it at another while
working around a weird cursor corner-case.
---
 src/compiler/nir/nir.c | 15 +++++++++++++++
 src/compiler/nir/nir.h |  2 ++
 2 files changed, 17 insertions(+)

diff --git a/src/compiler/nir/nir.c b/src/compiler/nir/nir.c
index c515a30b626..bbb28aef890 100644
--- a/src/compiler/nir/nir.c
+++ b/src/compiler/nir/nir.c
@@ -845,6 +845,21 @@ nir_instr_insert(nir_cursor cursor, nir_instr *instr)
       nir_handle_add_jump(instr->block);
 }
 
+void
+nir_instr_move(nir_cursor cursor, nir_instr *instr)
+{
+   /* If the cursor happens to refer to this instruction (either before or
+    * after), don't do anything.
+    */
+   if ((cursor.option == nir_cursor_before_instr ||
+        cursor.option == nir_cursor_after_instr) &&
+       cursor.instr == instr)
+      return;
+
+   nir_instr_remove(instr);
+   nir_instr_insert(cursor, instr);
+}
+
 static bool
 src_is_valid(const nir_src *src)
 {
diff --git a/src/compiler/nir/nir.h b/src/compiler/nir/nir.h
index 92ab3a699cc..c40a88c8ccc 100644
--- a/src/compiler/nir/nir.h
+++ b/src/compiler/nir/nir.h
@@ -2318,6 +2318,8 @@ nir_after_cf_list(struct exec_list *cf_list)
  */
 void nir_instr_insert(nir_cursor cursor, nir_instr *instr);
 
+void nir_instr_move(nir_cursor cursor, nir_instr *instr);
+
 static inline void
 nir_instr_insert_before(nir_instr *instr, nir_instr *before)
 {
-- 
2.17.1