(*)Add parentheses to continuity_PPM curv_3 expressions #574
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Added parentheses to 8 expressions like `curv_3 = h_W(i) + h_E(i) - 2.0*h(i)` in zonal_flux_layer, zonal_flux_thickness, merid_flux_layer and merid_flux_thickness, changing them to `curv_3 = (h_W(i) + h_E(i)) - 2.0*h(i)`. This change enforces the order of arithmetic that is required to give rotational symmetry, but it also is the order that the Intel, GNU, and Nvidia compliers were all already using in these expressions. Moreover, had the order of arithmetic ever been anything else, this would have led to failures in our rotational consistency and redundant point consistency testing, and almost certainly would have been detected before. However, by adding these parentheses, there is a remote chance that the addition of these parentheses could change answers for some compiler or compiler settings we have never tested before. This change should not impact any FMA-enabled calculations. All answers are bitwise identical in the MOM6-examples regression suite as run on Gaea.
Codecov ReportAll modified and coverable lines are covered by tests ✅
Additional details and impacted files@@ Coverage Diff @@
## dev/gfdl #574 +/- ##
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Coverage 37.20% 37.21%
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Files 271 271
Lines 80475 80472 -3
Branches 15008 15008
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+ Hits 29943 29944 +1
+ Misses 44961 44957 -4
Partials 5571 5571 ☔ View full report in Codecov by Sentry. |
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Do to the risk that this PR might change answers in some FMA-enabled runs, we have decided to withdraw it for now, although we do plan to reintroduce if for consideration along with other changes that might change answers when FMAs are enabled. |
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Added parentheses to 8 expressions like
curv_3 = h_W(i) + h_E(i) - 2.0*h(i)inzonal_flux_layer(),zonal_flux_thickness(),merid_flux_layer()andmerid_flux_thickness(), changing them tocurv_3 = (h_W(i) + h_E(i)) - 2.0*h(i). This change enforces the order of arithmetic that is required to give rotational symmetry, but it also is the order that the Intel, GNU, and Nvidia compliers were all already using in these expressions. Moreover, had the order of arithmetic ever been anything else, this would have led to failures in our rotational consistency and redundant point consistency testing, and almost certainly would have been detected before. However, by adding these parentheses, there is a remote chance that the addition of these parentheses could change answers for some compiler or compiler settings we have never tested before. This change should not impact any FMA-enabled calculations. All answers are bitwise identical in the MOM6-examples regression suite as run on Gaea.