Fix an off-by-one error in replay checkpoint loading.#18261
Merged
LibretroAdmin merged 1 commit intolibretro:masterfrom Sep 16, 2025
Merged
Fix an off-by-one error in replay checkpoint loading.#18261LibretroAdmin merged 1 commit intolibretro:masterfrom
LibretroAdmin merged 1 commit intolibretro:masterfrom
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The issue is that a replay frame read on core frame K stores the inputs for frame K along with the core state as of *the end of frame K*, in other words the beginning of frame K+1. To fix it, and to make sure existing replays play back properly, the `core_unserialize` call in bsvmovie.c has been deferred to the following invocation of `bsv_movie_read_next_events`, so that frame K+1 is deserialized just before reading the inputs for frame K+1. Some refactoring has also been done to simplify the number and timing of calls to bsv_movie functions from runloop.c.
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The issue is that a replay frame read on core frame K stores the inputs for frame K along with the core state as of the end of frame K, in other words the beginning of frame K+1. To fix it, and to make sure existing replays play back properly, the
core_unserializecall in bsvmovie.c has been deferred to the following invocation ofbsv_movie_read_next_events, so that frame K+1 is unserialized (restored) just before reading the inputs for frame K+1.Some refactoring has also been done to simplify the number and timing of calls to bsv_movie functions from runloop.c.