[PATCH] PR tree-optimization/16808: verify_ssa failed: Missing definition for SSA_NAME

[Jie Zhang]

Hi Jeff,

> 
> This seems like the wrong way to approach this problem and rather
> heavy-weight.  We're really trying to get away from calling back
> into the SSA renamer as often as we currently do.
> 

I know it is rather heavy-weight. I thought about simply replacing all 
the uses of the results of the being deleted v_may_defs with their 
operands. But I could not find a clear way to achieve this. So I just 
delete the v_may_defs and do rename.

> 
> I suggest waiting until Andrew's immediate uses work is done -- it
> may fix this problem as a side effect.  At the least it will make
> updating the SSA graph trivial for this kind of thing.
> 
Do you mean Andrew MacLeod? Where can I find the information of his 
immediate uses work? Is this 
<http://gcc.gnu.org/ml/gcc/2004-06/msg00902.html> the best place? Thanks.


cheers
-- 
Jie