[cfe-dev] Branches &,&&
kastrati at informatik.uni-mannheim.de
Thu Jun 11 06:06:59 PDT 2015
I'm turning to you with regards to an unwanted
optimization/un-optimization that clang++ (all versions that I tested,
in the following link) is generating, see the code in the following link:
The assembly code generated for both methods "amp", "ampamp" is the
practically the same, when using the optimization flag "-O3". However,
I'm interested to have a single jump for the code in the method "amp",
as branch misprediction penalty is very high otherwise. It should
generate a single jump, when using single ampersand (&), something that
icc13 is already doing (try it in the link above).
Is there any optimization flag that I should set, in order to avoid this
feature when using "-O3"?
I made a similar question to the g++ community, however this seems to be a bug (performance bug) with g++.
Thank you in advance
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