This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [tree-ssa Too many edges in CFG


On Thu, 2003-05-08 at 11:41, Andrew MacLeod wrote:
> On Thu, 2003-05-08 at 11:37, Diego Novillo wrote:
> > On Thu, 2003-05-08 at 11:21, Andrew MacLeod wrote:
> > 
> > > That won't be good enough, we're going to need those copy-out operations
> > > before all function call locations anyway, so its automatically going to
> > > happen before the no-return call. That makes the edge extraneous anyway.
> > > 
> > Of course.  My point was that by having these edges, it is easy to
> > discover in which blocks we need to insert the copies.  We obviously
> > have to insert them before the non-returning call.
> 
> That is no reason to have an edge in the flow graph. All function-calls
> 'exit' the function. So we might need copy's at every function location,
> returning or not. 
> 
Indeed.  There goes my argument then.  Yes, there's no need to have that
edge.  We will have to traverse all the blocks anyway.


Diego.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]