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Ryan Houdek
dcfbc2f20e
When #2722 implemented this initially and #4271 switched over to signed int16_t there was assumptions made that int16_t was a reasonable trade-off in encoding size versus needing to deal with 8-bit values being too small in some cases. In the common case we are almost always encoding 8-bit values because instructions are typically linear (and less than 15-bytes in size), but 16-bit was chosen because optimizing JIT and multiple instructions that don't cause exceptions can add up to larger than 8-bit. Instead of hardcoding 16-bit values, implement a variable length integer class where ~96.8% of values are 8-bit encoded, and the remaining 3.19% are encoded using 16-bit. Due to some constraints that #4271 put in place, we can basically guarantee currently that branch targets are within 16-bit. The VL class does support 32-bit and 64-bit as well so if we change behaviour then nothing needs to change. Some stats when running Sonic Mania with multiblock enabled. Encoded integers: 3,504,907 Encoded 8-bit: 3,393,095 (96.8%) Encoded 16-bit: 111,812 (3.19%) Encoded 32/64-bit: 0 Encoded Size: 3,615,181 bytes (3.44MiB) Fixed encoded size: 7,007,604 bytes (6.68MiB) Definitely worth using and saves the headache of large RIP/PC offsets causing problems.