RE: [PATCH v3 3/4] x86/alternative: Rewrite optimize_nops() some

From: David Laight
Date: Wed Feb 08 2023 - 18:04:35 EST


From: Andrew.Cooper3@xxxxxxxxxx
> Sent: 08 February 2023 19:52
...
> Unconditional jmps cost branch prediction these days, and won't be
> successfully predicted until taken.

That is sad :-(

Don't they also use the BTB for the target address?
So even if predicted taken the cpu can speculate from
the wrong address??

David

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