[Bug tree-optimization/26854] Inordinate compile times on large routines

["law at redhat dot com" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #4 from law at redhat dot com  2006-04-19 15:32 -------
OK, as expected, DOM was doing something totally stupid with immediate uses. 
On my x86 box I've got a patch which takes us from ~250 seconds in DOM to
around 5.
I'm going to get this fix bootstrapped and regression tested, then port it to
mainline (where things are slightly different/rearranged, but the same core
problem exists).

Unfortunately, those gains are dwarfed by the wall-clock time burned
swapping/paging due to memory usage in other passes.

The worst memory offenders (in pain order) are:

  reorder blocks (possible given the number of blocks/edges in this code)
  expand (???  possibly being charged for some other passes time)
  global-alloc

Mainline has a different memory pain profile -- the new RTL invariant code
motion pass goes absolutely nuts memory-wise.

I'm not planning to work on any of the memory consumption issues.


-- 

law at redhat dot com changed:

           What    |Removed                     |Added
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                 CC|                            |rakdver at gcc dot gnu dot
                   |                            |org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26854