[LLVMdev] Which pass converts call printf to puts?

[Christoph Erhardt]

Hi Thomson,

> I found that LLVM optimized the IR by replacing printf with puts. I
> wondered  which pass did this optimization? And is it common that puts
> is faster (and some other metric) than printf?
yes, it's safe to assume that puts() is always faster than printf()
because it doesn't have to perform all the format-string parsing.

Also, the implementation of puts() is a lot smaller - which might matter
if the binary is linked statically and code size is important.

Best regards,
Christoph