[Bug tree-optimization/23948] [4.1 Regression] internal compiler error: verify_stmts failed

["paolo dot bonzini at lu dot unisi dot ch" <gcc-bugzilla at gcc dot gnu dot org>]

------- Additional Comments From paolo dot bonzini at lu dot unisi dot ch  2005-09-21 14:33 -------
Subject: Re:  [4.1 Regression] internal compiler
 error: verify_stmts failed

rguenth at gcc dot gnu dot org wrote:

>------- Additional Comments From rguenth at gcc dot gnu dot org  2005-09-21 14:18 -------
>We insert the reciprocal computation correctly after the call to 
>  double prrs = potentially_runnable_resource_share();
>but as this call may trap and is the last instruction in the basic block,
>inserting there is obviously bogous.
>
>We'd need to insert a new BB or need a way to insert on the EXIT_EDGE.  And
>make sure critical edges are split.
>  
>
No, I think we have to rethink the place where we insert the division.  
It needs to be closer to the divide (just before), not right after the 
definition.  When we have flag_trapping_math, this is quite hard to do 
(there may be even multiple places to insert the divide!).

I also did not understand why you had to fiddle with postdominators :-) 
to fix PR23309.  I have a prototype patch but it will probably be a 
while before I can sit, look if it really works, and test it properly.

Paolo


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23948