Re:The x86 architecture is the weirdo, part 2
by zozbot234 on Friday April 22, 2022 @06:34AM
(#31120040)
Not having condition codes actually cleans up the semantics a lot - no need to define the CC effects for each and every insn. It's also helpful to high-performance implementations, since the condition code register would otherwise enter as a dependency in every insn.
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Re:The x86 architecture is the weirdo, part 2
by kryptiskt on Friday April 22, 2022 @06:49AM
(#31120116)
Sure, there are reasons for it being that way, but it makes it stick out from the mainstream. For example, if you're writing a codegen, before RISC-V you could assume that you had CMOVE and now you can't. The risk is then that the RISC-V backend will emit some clumsy sequence that emulates CMOVE, to make it fit in with the others.