Remove dead store to _Count in _Sort_unchecked #445
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…re forced to initialize in the constexpr algorithms review by eliminating the variable entirely.
CaseyCarter
suggested changes
Jan 23, 2020
…r 2, add _INLINE_VAR to _ISORT_MAX.
BillyONeal
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CaseyCarter
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Jan 23, 2020
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Based on Casey's comment I want to fix callers to _Insertion_sort_unchecked. |
… _First != _Last precondition since all callers already had count.
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In #425 I was forced to add a dead initialization for the
_Countvariable in_Sort_uncheckedin order to comply with constexpr rules. Also,_Sort_uncheckedhad somewhat complex assignment-in-conditional-expressions going on. This change moves the code around such that the _Count variable is assigned once.I tested with the Visual Studio 2019 version 16.5 preview 2 compiler and verified there were no meaningful changes in the generated code (except for a couple of removed branches for the
>>1instead of/2and>>2instead of/4), so the performance should be unaffected. (Note that performance of anything related tosortis super duper sensitive)Checklist
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