Re: [patch] tree-ssa-sink.c: Don't restrict immediate uses that weconsider.

[Kazu Hirata <kazu at cs dot umass dot edu>]

Hi Daniel,

> > Jeff, yes, I am moving an "if" statement that should always be true.
> 
> Then your original claim for the reason for this patch:
> 
> "> > It's dangerous to have an "if" statement to restrict the set of
> > > immediate uses that we consider like so
> > > 
> > >   if (PHI_ARG_DEF (usestmt, idx) == var)
> > > 
> > > because the location that we come up with may not dominate all uses.
> "
> is false.

Ah, sorry for lack of words.  I meant "... could be dangerous if PHI
nodes were allowed to contain ADDR_EXPRs that are not TREE_INVARIANT.
Currently, such ADDR_EXPRs aren't allowed, so in the end, we are just
removing an "if" statement whose condition is always true.

Kazu Hirata