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From: "steven at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/38474] [4.3/4.4 Regression] slow compilation at -O0 (callgraph optimization, inline heuristics, expand )
Date: Wed, 17 Dec 2008 19:42:00 -0000	[thread overview]
Message-ID: <20081217194049.31172.qmail@sourceware.org> (raw)
In-Reply-To: <bug-38474-6642@http.gcc.gnu.org/bugzilla/>



------- Comment #33 from steven at gcc dot gnu dot org  2008-12-17 19:40 -------
cfgexpand.c:defer_stack_allocation() has this gem:

  /* Without optimization, *most* variables are allocated from the
     stack, which makes the quadratic problem large exactly when we
     want compilation to proceed as quickly as possible.  On the
     other hand, we don't want the function's stack frame size to
     get completely out of hand.  So we avoid adding scalars and
     "small" aggregates to the list at all.  */
  if (optimize == 0 && tree_low_cst (DECL_SIZE_UNIT (var), 1) < 32)
    return false;

In our case, most variables are of type mpfr_type, which is ... yes, 32 bytes
:-)


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38474


  parent reply	other threads:[~2008-12-17 19:42 UTC|newest]

Thread overview: 52+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-12-10 15:26 [Bug middle-end/38474] New: slow compilation at -O0 (callgraph optimization, inline heuristics, ggc " jv244 at cam dot ac dot uk
2008-12-10 15:27 ` [Bug middle-end/38474] " jv244 at cam dot ac dot uk
2008-12-10 15:41 ` [Bug middle-end/38474] slow compilation at -O0 (callgraph optimization, inline heuristics, " rguenth at gcc dot gnu dot org
2008-12-10 16:14 ` jv244 at cam dot ac dot uk
2008-12-10 16:58 ` rguenth at gcc dot gnu dot org
2008-12-10 22:35 ` jv244 at cam dot ac dot uk
2008-12-10 22:49 ` rguenth at gcc dot gnu dot org
2008-12-10 22:58 ` jv244 at cam dot ac dot uk
2008-12-11  8:28 ` jv244 at cam dot ac dot uk
2008-12-11 11:35 ` rguenth at gcc dot gnu dot org
2008-12-11 12:04 ` jv244 at cam dot ac dot uk
2008-12-15 19:39 ` jv244 at cam dot ac dot uk
2008-12-15 21:19 ` steven at gcc dot gnu dot org
2008-12-15 21:29 ` steven at gcc dot gnu dot org
2008-12-15 21:54 ` steven at gcc dot gnu dot org
2008-12-15 21:56 ` steven at gcc dot gnu dot org
2008-12-15 21:57 ` steven at gcc dot gnu dot org
2008-12-16  7:52 ` jv244 at cam dot ac dot uk
2008-12-16 11:59 ` jv244 at cam dot ac dot uk
2008-12-16 12:46 ` steven at gcc dot gnu dot org
2008-12-16 12:48 ` jv244 at cam dot ac dot uk
2008-12-16 12:50 ` jv244 at cam dot ac dot uk
2008-12-16 13:43 ` steven at gcc dot gnu dot org
2008-12-16 14:19 ` jv244 at cam dot ac dot uk
2008-12-16 14:21 ` jv244 at cam dot ac dot uk
2008-12-16 16:19 ` jv244 at cam dot ac dot uk
2008-12-16 16:28 ` steven at gcc dot gnu dot org
2008-12-16 16:31 ` jv244 at cam dot ac dot uk
2008-12-16 19:35 ` [Bug middle-end/38474] [4.3/4.4 Regression] " pinskia at gcc dot gnu dot org
2008-12-16 20:32 ` jv244 at cam dot ac dot uk
2008-12-17  6:52 ` jv244 at cam dot ac dot uk
2008-12-17  7:03 ` steven at gcc dot gnu dot org
2008-12-17  8:37 ` jv244 at cam dot ac dot uk
2008-12-17 12:59 ` jv244 at cam dot ac dot uk
2008-12-17 19:42 ` steven at gcc dot gnu dot org [this message]
2008-12-20  9:00 ` jv244 at cam dot ac dot uk
2008-12-20  9:56 ` steven at gcc dot gnu dot org
2008-12-20 11:33 ` [Bug middle-end/38474] [Meta] " jv244 at cam dot ac dot uk
2008-12-20 15:51 ` steven at gcc dot gnu dot org
2009-01-24 10:27 ` rguenth at gcc dot gnu dot org
2009-08-04 12:45 ` rguenth at gcc dot gnu dot org
2009-11-27  8:52 ` jv244 at cam dot ac dot uk
2009-11-27  9:00 ` jv244 at cam dot ac dot uk
2009-11-27 10:50 ` rguenth at gcc dot gnu dot org
2009-12-03 13:37 ` matz at gcc dot gnu dot org
2009-12-03 17:48 ` jv244 at cam dot ac dot uk
2009-12-03 21:05 ` matz at gcc dot gnu dot org
2009-12-08 13:56 ` matz at gcc dot gnu dot org
2010-05-22 18:33 ` rguenth at gcc dot gnu dot org
2010-05-23  6:31 ` jv244 at cam dot ac dot uk
2010-05-23 20:09 ` rguenth at gcc dot gnu dot org
2010-05-23 21:03 ` [Bug middle-end/38474] slow compilation at -O0 due to expand's temp slot goo steven at gcc dot gnu dot org

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