[LLVMdev] folding x * 0 = 0

[Bob Wilson]

On Mar 3, 2010, at 9:32 AM, Jochen Wilhelmy wrote:

> 
>> Is x*0 =>  0 true if isnan(x)?
>> 
> then where do I have to add it if I want to make it a non-standard 
> modification
> of my local llvm version?
> would it make sense to add a subset of float to llvm or a kind of modifier
> (e.g. valid float to indicate that it is always valid and not nan) to 
> allow more aggressive optimization?
> just like e.g. inbounds for load

You should check out the -enable-finite-only-fp-math and -enable-unsafe-fp-math options.