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A comment on A complete map of the Rust type system. Parent comment

Re:A complete map of the Rust type system by lock1 on Monday September 08, 2025 @06:15PM (#45174749) 

  > I do not understand your argument about branches, how would it hinder the jump instructions?
Extra set of logic for handling NaN cases? I don't think it's impossible, just kind of less intuitive. Jump instruction using integer w/o NaN always valid, while NaN-able integer sometimes invalid (ignoring whether the memory address can be accessed).
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Re:A complete map of the Rust type system by newpavlov on Monday September 08, 2025 @06:20PM (#45174808)
For absolute jumps you don't need extra logic, since CPUs could declare the last page always unmapped, so such jumps would always result in a page fault (similarly to the null page on most systems).

For relative non-immediate jumps the added logic is extremely simple (hardware exception on NaN) and should not (AFAIK) hinder performance of jumps in any way.

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