[LLVMdev] updated code size comparison

John Regehr regehr at cs.utah.edu
Thu Dec 17 09:22:39 PST 2009

Hi Paolo,

> I would also avoid testcases using volatile.  Smaller code on these testcases 
> is often a sign of miscompilation rather than optimization. For example, 
> http://embed.cs.utah.edu/embarrassing/src_harvested_dec_09/076389.c is 
> miscompiled on GCC 3.4 and SunCC 5.10.

Yeah, there are definitely several examples where small code is generated 
by miscompilation, especially of volatiles.

However I would prefer to leave these testcases in, unless there is a 
strong feeling that they are too distracting.  They serve as poignant 
little reminders about how easy it is to get volatile wrong...


More information about the llvm-dev mailing list