Re: PATCH: [gcc3.5 improvement branch] Very Simple constant propagation

[Dale Johannesen <dalej at apple dot com>]

On Feb 3, 2004, at 11:46 AM, Geoff Keating wrote:
> On Feb 3, 2004, at 8:19 AM, Jan Hubicka wrote:
> > > Execution times (seconds)
> > >  parser                : 881.58 (63%) usr   2.83 (20%) sys 884.32 
> > > (62%) wall
> >
> > Geoff,
> > I see I am not only one who get inadequately large amount of time 
> > spent
> > in parser with intermodule.  All the times goes into the final merging
> > of declarations across modules that is implemented with quadratic
> > complexity.  Do you think there is some chance to see this cut down to
> > resonable times?

I see this behavior also.

> Why do you think it's quadratic?  It looks like two loops over all 
> declarations to me.
>
> > I am also getting internal compiler error in dwarf2out later, but I've
> > failed to produce some testcase for this :(
>
> Testcases are very hard for this stuff, I recommend gdb.

There are several SPECs that fail to build with intermodule also, with 
a variety
of different errors.   It looks like there's some corruption going on; 
unfortunately it
will be a couple of days before anybody here has a chance to look at 
it.  It looked
like crafty might be the easiest to debug, there's obviously something 
gone wrong
with the merged type info in that case.