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Re: [RFC] Add conditional compare support


On Wed, 21 Aug 2013, Zhenqiang Chen wrote:

> SHORT_CIRCUIT expression will be converted to CCMP expressions
> at the end of front-end.

That doesn't sound like the right place to me.  We want the same code to 
be generated whether users write && and || directly or write corresponding 
sequences of if conditions.  In general we want to move away from 
optimizing complicated expressions in fold-const, towards having GIMPLE 
passes that detect the relevant patterns however they were written (and 
without needing to combine GIMPLE back into trees for passing through the 
old folder).  So, I think you should detect this at some point in the 
GIMPLE optimizations rather than changing fold-const at all (and as a 
consequence, you then shouldn't need to change front-end pretty-printers).

-- 
Joseph S. Myers
joseph@codesourcery.com


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