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avoid some calls to memset with array initializer - Mailing list pgsql-hackers

From Justin Pryzby
Subject avoid some calls to memset with array initializer
Date
Msg-id 20200102163834.GA3183@telsasoft.com
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Responses Re: avoid some calls to memset with array initializer  (rmrodriguez@carto.com)
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Is there any appetite for use of array initializer rather than memset, as in
attached ?  So far, I only looked for "memset.*null", and I can't see that any
of these are hot paths, but saves a cycle or two and a line of code for each.

gcc 4.9.2 with -O2 emits smaller code with array initializer than with inlined
call to memset.

$ wc -l contrib/pageinspect/heapfuncs.S? 
 22159 contrib/pageinspect/heapfuncs.S0
 22011 contrib/pageinspect/heapfuncs.S1

Also true of gcc 5.4.  And 7.3:

 25294 contrib/pageinspect/heapfuncs.S0
 25234 contrib/pageinspect/heapfuncs.S1
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