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Megol · 15 August 2016, 20:21

My post got eaten. Short version:

Hint bits are not worth it in a modern processor. They can be worth it in simple processors or to shave a few clocks from run-once code (exceptions etc.).

The bit can be used for better things, my version:
0000 0000 -> 16 bit displacement
1111 1111 -> 32 bit displacement
0000 0001 -> 64 bit displacement
xxxx xxx0 -> normal 8 bit displacement
xxxx xxx1 -> available for extension

Any incompatible treatment of the LSb should be disabled by default and enabled by the OS if needed.

15 August 2016, 20:21	#73
Megol Registered User Join Date: May 2014 Location: inside the emulator Posts: 377	My post got eaten. Short version: Hint bits are not worth it in a modern processor. They can be worth it in simple processors or to shave a few clocks from run-once code (exceptions etc.). The bit can be used for better things, my version: 0000 0000 -> 16 bit displacement 1111 1111 -> 32 bit displacement 0000 0001 -> 64 bit displacement xxxx xxx0 -> normal 8 bit displacement xxxx xxx1 -> available for extension Any incompatible treatment of the LSb should be disabled by default and enabled by the OS if needed.