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Re: RFC: Preserving order of functions and top-level asms via cgraph

On Sun, Apr 10, 2005 at 06:13:14PM -0400, Daniel Jacobowitz wrote:
> This has been on the table for ages, but no one's gotten around to doing it. 
> I'm attaching a (mostly untested) patch which fixes the simple cases.  For
> instance, it causes this test to come out in the expected order:
> void func1() { }
> asm ("# ASM");
> void func2() { }
> It doesn't handle variable declarations, and it won't be useful until it
> does.  Right now declarations are written to the assembly file early, before
> functions are assembled.  Steven pointed out (thank you, Steven) that this
> is much easier on the tree-profiling branch, where that is no longer the
> case.  So, I'm not going to extend the patch to declarations until that
> piece is merged.
> In the mean time, any fundamental objections to the approach?
> Also, are there any other major reasons why people use -fno-unit-at-a-time,
> besides this one?  I would like to see the option go away, and to enable
> unit-at-a-time always.  If for no other reason than to simplify the bits of
> cgraph which handle it.
> Yes, that does incur a measurable (~2% ?) memory and time overhead at -O0. 
> Much less than I would have expected, but my measurements were not very
> thorough.  Note that C++ already does this, and has for a while.

I have not retested this patch, but I would like to restart discussion
on it.  Rereading, the only person with an objection seemed to be
Richard Sandiford; Richard, you wanted specific extensions instead
(which I think is impractical) or better documentation (which is sane
but I don't think I'm qualified to write).  Is that right?

Does anyone else object to the patch?  Anyone interested in writing
the documentation saying what is (after the patch) supported for

Daniel Jacobowitz
CodeSourcery, LLC

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