Avoid division operation using _sizeCalssRatioLog - #7918
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_sizeCalssRatioLog is used to calculate log value for desired base: _sizeCalssRatioLog = logf(base); log_base_for_value = logf(value) / _sizeCalssRatioLog. Division operation can be expensive so code can be optimized by using multiplication operation instead of division. Also I renamed precalculated variable name to _sizeCalssRatioLogInversed to reflect this change: _sizeCalssRatioLogInversed = 1.0f / logf(base); log_base_for_value = logf(value) / _sizeCalssRatioLogInversed. Signed-off-by: Dmitri Pivkine <Dmitri_Pivkine@ca.ibm.com>
amicic
reviewed
Sep 2, 2025
| @@ -238,7 +238,7 @@ class MM_LargeObjectAllocateStats : public MM_Base { | |||
| _largeObjectThreshold(0), | |||
| _veryLargeEntrySizeClass(0), | |||
| _sizeClassRatio(0.0), | |||
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you can also change this to 0.0f for style consistency
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|
@babsingh please review/merge |
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|
jenkins build all |
babsingh
approved these changes
Sep 3, 2025
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_sizeCalssRatioLog is used to calculate log value for desired base: _sizeCalssRatioLog = logf(base);
log_base_for_value = logf(value) / _sizeCalssRatioLog. Division operation can be expensive so code can be optimized by using multiplication operation instead of division. Also I renamed precalculated variable name to _sizeCalssRatioLogInversed to reflect this change:
_sizeCalssRatioLogInversed = 1.0f / logf(base);
log_base_for_value = logf(value) / _sizeCalssRatioLogInversed.