Commit 13bcfa0ea8 for aom

commit 13bcfa0ea8556f355b7bfa9158a473a1723c442b
Author: Wan-Teh Chang <wtc@google.com>
Date:   Fri Oct 23 11:46:54 2026 -0700

    Better modulo counter cm->frame_presentation_time

    pts64 % modulus is negative when pts64 is negative. Although pts64 may
    never be negative, it is better to avoid this issue by switching to the
    expression pts64 & (modulus - 1). This works because modulus is a power
    of 2.

    Bug: b:444969593
    Change-Id: I9b8b3a677d593c3b0bfc692795f598d06592eac8

diff --git a/av1/encoder/encode_strategy.c b/av1/encoder/encode_strategy.c
index 8889d7bb84..26ba6f2bef 100644
--- a/av1/encoder/encode_strategy.c
+++ b/av1/encoder/encode_strategy.c
@@ -1519,8 +1519,8 @@ int av1_encode_strategy(AV1_COMP *const cpi, size_t *const size,
           ticks_to_timebase_units(timestamp_ratio, *time_stamp);
       const int frame_presentation_time_length =
           cm->seq_params->decoder_model_info.frame_presentation_time_length;
-      const int64_t modulus = 1LL << frame_presentation_time_length;
-      cm->frame_presentation_time = (uint32_t)(pts64 % modulus);
+      const int64_t pts_mask = (1LL << frame_presentation_time_length) - 1LL;
+      cm->frame_presentation_time = (uint32_t)(pts64 & pts_mask);
     }
   }