[Enhancement]generate new range faster #55627
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Signed-off-by: zombee0 <ewang2027@gmail.com>
be/src/storage/range.h
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| start = start > i && filter->data()[i] == 1 ? i : start; | ||
| end = end < i && filter->data()[i] == 1 ? i : end; | ||
| int32_t tail_index = filter->size() - 1 - i; | ||
| end = end < tail_index && filter->data()[tail_index] == 1 ? tail_index : end; |
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What is this function used for? I couldn't understand its meaning just by looking at the code. Is it for finding the upper and lower bounds? Why not just write two loops—one for finding the start and one for finding the end?
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Yes, it's used to find upper and lower bounds, i think less loop, less branch, we also use ?: to reduce branch.
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i think it can be optimized as cmov
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I checked assembly code
complier cann't generate branch-less code, and it's not critical part in cpu usage,
so just use simple way
Signed-off-by: zombee0 <ewang2027@gmail.com>
complier cann't generate branch-less code, and it's not critical part in cpu usage, so just use simple way Signed-off-by: zombee0 <ewang2027@gmail.com>
[Java-Extensions Incremental Coverage Report]✅ pass : 0 / 0 (0%) |
[FE Incremental Coverage Report]✅ pass : 0 / 0 (0%) |
[BE Incremental Coverage Report]✅ pass : 6 / 6 (100.00%) file detail
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@Mergifyio backport branch-3.4 |
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@Mergifyio backport branch-3.3 |
✅ Backports have been created
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✅ Backports have been created
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Signed-off-by: zombee0 <ewang2027@gmail.com> (cherry picked from commit 712fc09)
Signed-off-by: zombee0 <ewang2027@gmail.com> (cherry picked from commit 712fc09) # Conflicts: # be/src/storage/range.h
Why I'm doing:
I checked assembly code, complier can't generate branch-less code,
and it's not critical part in cpu usage, so just use simple way
What I'm doing:
Fixes #issue
What type of PR is this:
Does this PR entail a change in behavior?
If yes, please specify the type of change:
Checklist:
Bugfix cherry-pick branch check: