Reply to post: Re: Conditional execution

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Torben Mogensen

Re: Conditional execution

Conditional execution was in Thumb2 replaced by an if-then-else instruction that specifies which of the following up to four instructions are executed when the condition is true and which are executed when the condition is false. Specifying ahead of time is better for pipelining, ARM64 has, IIRC, done away with generalized conditional execution entirely, except for jumps. I suspect this is to make implementation simpler and because branch prediction can make jumps almost free, so all you would save with conditional instructions is code space.

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