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A comment on Bubble sort slower with -O3 than -O2 with GCC. Parent comment

Re:Bubble sort slower with -O3 than -O2 with GCC by nly on Sunday October 17, 2021 @12:32PM (#28897641)
What about when you factor in PGO? (-fprofile-generate & -fprofile-use)
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Re:Bubble sort slower with -O3 than -O2 with GCC by mhh__ on Sunday October 17, 2021 @01:03PM (#28897881)
This is the rub. the compiler is flying completely blind without PGO.

I turned on PGO for the D compiler recently and it compiled it's tests 15% faster. Boom.

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Re:Bubble sort slower with -O3 than -O2 with GCC by codr7 on Sunday October 17, 2021 @01:20PM (#28898019)
Haven't really been down that rabbit hole yet, thanks for reminding me.
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