[LLVMdev] missed optimizations

[John Regehr]

> There is an unbounded number of things the optimizer could potentially
> handle, but we only have a bounded amount of engineering effort.  I'd
> rather drive forward based on actual needs of code observed in the wild.

Fair enough.

The one I submitted, btw, is a safety check for a shift operation, called 
with constant arguments-- it is almost certainly reasonable to expect that 
a good compiler at a nontrivial optimization level will make these checks 
go away.

As a compromise, would you consider adding a "run opt to fixpoint" option 
to llvm-gcc?  Obviously I can do that using a pipeline but in practice the 
pain of abandoning the simple compilation driver is too much.

John