[LLVMdev] folding x * 0 = 0

[Jim Grosbach]

On Mar 3, 2010, at 3:20 PM, Chris Lattner wrote:

> 
> On Mar 3, 2010, at 1:53 PM, David Greene wrote:
> 
>>> 
>>> IMO rounding mode should be explicitly marked on the
>>> instruction as well.
>> 
>> That would also be useful for some GPUs where each instruction can specify
>> its own rounding mode.
> 
> SSE4 also has this for at least one conversion instruction.

As does ARM NEON. Sorta. vcvt normally uses round-to-zero, but it can optionally use the mode specified by the control register instead.