Message327467
See also PR 9784 where Raymond shown assempler code generated for two variants.
There is the similar difference on 64-bit platform with GCC 7.3:
$ gcc -O3 -o issue28397 issue28397-2.c
$ time ./issue28397-2 0
real 0m2,740s
user 0m2,739s
sys 0m0,000s
$ time ./issue28397-2 1
real 0m2,449s
user 0m2,449s
sys 0m0,000s
But with GCC 8.2 there is not a difference.
$ time ./issue28397-2 0
real 0m2,498s
user 0m2,498s
sys 0m0,000s
$ time ./issue28397-2 1
real 0m2,500s
user 0m2,496s
sys 0m0,004s
Both versions generate the same code for tested functions, there are only minor differences in the main() function (some independent instructions are reordered). I don't know what is the cause of such difference. |
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Date |
User |
Action |
Args |
2018-10-10 12:03:32 | serhiy.storchaka | set | recipients:
+ serhiy.storchaka, rhettinger, vstinner, skrah, socketpair, sir-sigurd |
2018-10-10 12:03:32 | serhiy.storchaka | set | messageid: <1539173012.32.0.788709270274.issue28397@psf.upfronthosting.co.za> |
2018-10-10 12:03:32 | serhiy.storchaka | link | issue28397 messages |
2018-10-10 12:03:32 | serhiy.storchaka | create | |
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