[PATCH v4 3/3] vkd3d-shader/ir: Sort loop intervals.

[Giovanni Mascellani]

From: Giovanni Mascellani

---
 libs/vkd3d-shader/ir.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/libs/vkd3d-shader/ir.c b/libs/vkd3d-shader/ir.c
index 4997b475a..bf565c2bc 100644
--- a/libs/vkd3d-shader/ir.c
+++ b/libs/vkd3d-shader/ir.c
@@ -3763,6 +3763,20 @@ fail:
     return ret;
 }

+/* Sort loop intervals first by ascending begin time and then by
+ * descending end time, so that inner intervals appear after outer
+ * ones and disjoint intervals appear in their proper order. */
+static int compare_loop_intervals(const void *ptr1, const void *ptr2)
+{
+    const struct cfg_loop_interval *interval1 = ptr1;
+    const struct cfg_loop_interval *interval2 = ptr2;
+
+    if (interval1->begin != interval2->begin)
+        return vkd3d_u32_compare(interval1->begin, interval2->begin);
+
+    return -vkd3d_u32_compare(interval1->end, interval2->end);
+}
+
 static enum vkd3d_result vsir_cfg_generate_synthetic_loop_intervals(struct vsir_cfg *cfg)
 {
     enum vkd3d_result ret;
@@ -3876,6 +3890,8 @@ static enum vkd3d_result vsir_cfg_generate_synthetic_loop_intervals(struct vsir_
         }
     }

+    qsort(cfg->loop_intervals, cfg->loop_interval_count, sizeof(*cfg->loop_intervals), compare_loop_intervals);
+
     if (TRACE_ON())
         for (i = 0; i < cfg->loop_interval_count; ++i)
             TRACE("%s loop interval %u - %u\n", cfg->loop_intervals[i].synthetic ? "Synthetic" : "Natural",