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Re: ggc_pop_context speedup


On Wednesday, February 5, 2003, at 02:27 PM, Mike Stump wrote:
- Please don't use varrays like this. The intent is that in the future
all varrays will be GCed, so adding a case where they must not be GCed
will mean that the existing hackery has to be preserved forever.
? Not sure what to do about this one, can we push this until later? In the end, we either lower the code into malloc/realloc or replicate varrays for non GCed data structures.
[ after talking with Geoff ]

Ok, updated to not use varray.h

- Would I be correct in saying that this adds about 120k to the
  minimum memory footprint of the compiler?  That seems like a lot.
We can tune the initial PTE count down to 10, if we wanted to. I tested small files and they don't notice it either way. For large files, cutting this down to 10 might make compilations a hair slower, though, reallocing to 15000*4 bytes doesn't take all that long, and the cost would be well hidden in the cost of the large file anyway.

Do you have a number you'd rather see? The previous number is either the maximal or 1/2 the maximal number I saw with a large C++ application (Finder_FE).
Ok, updated to use 128 (around 1kB).

- Did you test this with --enable-checking=gc,gcac?
I regtested with gc.  gcac shouldn't make a difference.
[ Geoff wants a gcac run as well ]

Ok, pending re-regtest with gcac on?

Oh, and this should resolve all of Mark's items he pointed out as well.

Attachment: popcontext-fsf-2.diffs
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