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A comment on A Go implementation of Poly1305 that makes sense. Parent comment

Re:A Go implementation of Poly1305 that makes sense by leni536 on Wednesday April 03, 2019 @09:37AM (#19563171)
gcc can optimize generic code for a carry check. To be fair both clang and msvc fails to optimize this specific case.

https://godbolt.org/z/6WXfnL

Edit: OK, I have much worse time generating "adc" instructions, and only gcc sees the opportunity to emit "setc" where appropriate. I see the issue now.

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Re:A Go implementation of Poly1305 that makes sense by giovannibajo1 on Wednesday April 03, 2019 @12:12PM (#19564573)
Correct, gcc can generate "setc" but not "adc", AFAIK.
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