https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109378
Bug ID: 109378
Summary: improve __builtin_sqrt
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: g.peterh...@t-online.de
Target Milestone: ---
Hello gcc team,
https://godbolt.org/z/Wa1rfxrPo
when I write a function that contains std::sqrt, it always contains the nan(?)
tests for the argument. E.g. sqrtf64.
If I use my_sqrt the tests are done inside sqrt and not in the calling function
- clear (because noinline).
Wouldn't it be better to rewrite __builtin_sqrt so that these tests are done
inside __builtin_sqrt and not already in the calling context?
This would have the advantage that std::sqrt would not "contaminate" the
calling function with conditional jumps and thus inflate it.
I can make this clear with foo vs. bar.
And of course __builtin_sqrt must be able to be vectorized automatically and
must be inline for certain contexts (e.g. __FAST_MATH__).
regards
Gero
