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[Bug target/40603] unnecessary conversion from unsigned byte load to signed byte load



------- Comment #2 from ramana dot radhakrishnan at arm dot com  2009-07-01 09:13 -------
Subject: Re:   New: unnecessary conversion from unsigned
        byte load to signed byte load


> Unfortunately in thumb mode, loading a signed byte costs more than loading an
> unsigned byte and comparing with 0 has same cost as comparing with 0x7F.

I don't know of any core where loading a signed byte is more expensive
than unsigned byte in thumb mode. What did you have in mind ?

I suspect what you mean is that the sign extension here is not required
and we could get away with ldrb.




> 


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40603


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