diff --git a/libs/vkd3d-shader/ir.c b/libs/vkd3d-shader/ir.c
index 8b8885fc8..1098e4d39 100644
--- a/libs/vkd3d-shader/ir.c
+++ b/libs/vkd3d-shader/ir.c
@@ -1740,14 +1740,21 @@ static enum vkd3d_result vsir_program_lower_instructions(struct vsir_program *pr
 static enum vkd3d_result vsir_program_ensure_ret(struct vsir_program *program,
         struct vsir_transformation_context *ctx)
 {
+    struct vsir_program_iterator it = vsir_program_iterator(&program->instructions);
     static const struct vkd3d_shader_location no_loc;
-    if (program->instructions.count
-            && program->instructions.elements[program->instructions.count - 1].opcode == VSIR_OP_RET)
+    struct vkd3d_shader_instruction *ins;
+
+    ins = vsir_program_iterator_tail(&it);
+
+    if (ins && ins->opcode == VSIR_OP_RET)
         return VKD3D_OK;
 
-    if (!shader_instruction_array_insert_at(&program->instructions, program->instructions.count, 1))
+    if (!vsir_program_iterator_insert_after(&it, 1))
         return VKD3D_ERROR_OUT_OF_MEMORY;
-    vsir_instruction_init(&program->instructions.elements[program->instructions.count - 1], &no_loc, VSIR_OP_RET);
+
+    ins = vsir_program_iterator_next(&it);
+    vsir_instruction_init(ins, &no_loc, VSIR_OP_RET);
+
     return VKD3D_OK;
 }
 
diff --git a/libs/vkd3d-shader/vkd3d_shader_private.h b/libs/vkd3d-shader/vkd3d_shader_private.h
index 1c622b97d..4027395b1 100644
--- a/libs/vkd3d-shader/vkd3d_shader_private.h
+++ b/libs/vkd3d-shader/vkd3d_shader_private.h
@@ -1453,6 +1453,13 @@ static inline struct vkd3d_shader_instruction *vsir_program_iterator_head(
     return vsir_program_iterator_current(iterator);
 }
 
+static inline struct vkd3d_shader_instruction *vsir_program_iterator_tail(struct vsir_program_iterator *iterator)
+{
+    iterator->idx = iterator->array->count - 1;
+
+    return vsir_program_iterator_current(iterator);
+}
+
 static inline struct vkd3d_shader_instruction *vsir_program_iterator_next(
         struct vsir_program_iterator *iterator)
 {