[cfe-dev] Question about size optimization and PRE

[jingu@codeplay.com via cfe-dev]

Hi All,

I have a question about the opportunity of size optimization in clang. 
As you know, the PRE(partial redundancy elimination) copies partially 
available instructions to paths in which the instruction is not 
available. I think it makes code size bigger. I can see the PRE 
implementation in llvm's GVN pass. However, I can not see the options 
like '-enable-pre=false' or '-enable-load-pre=fasle' on clang with size 
optimization. How do you think about disabling PRE with clang's size 
optimization? If I missed something, please let me know.

Thanks,

JinGu Kang