Re: SRA bit-field optimization

[Alexandre Oliva <aoliva@redhat.com>]

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On Oct  5, 2007, Alexandre Oliva <aoliva@redhat.com> wrote:

> On Oct  5, 2007, "Richard Guenther" <richard.guenther@gmail.com> wrote:

>> On 10/2/07, Richard Guenther <richard.guenther@gmail.com> wrote:
>>> It seems this was committed now, and causes ncurses build to fail on
>>> x86_64:
>> Btw, this is PR33655.

> Thanks.  Here's a patch that fixes the problem, that I've just started
> bootstrapping and regtesting on x86_64-linux-gnu.  Ok to install if it
> passes?

H.J.Lu ran into a problem on ia64-linux-gnu, and Jim Wilson provided
the following patch.  I'm checking it in as it is an obvious
improvement.  Please let me know whether it causes any further
problem.


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for gcc/ChangeLog
from  James E. Wilson  <wilson@specifix.com>

	PR tree-optimization/33655
	PR middle-end/22156
	* tree-sra.c (bitfield_overlaps_p): When fld->element is INTEGER_CST,
	convert it to bitsizetype before size_binop call.

Index: gcc/tree-sra.c
===================================================================
--- gcc/tree-sra.c.orig	2007-10-09 01:45:08.000000000 -0300
+++ gcc/tree-sra.c	2007-10-09 01:50:52.000000000 -0300
@@ -2906,7 +2906,8 @@ bitfield_overlaps_p (tree blen, tree bpo
   else if (TREE_CODE (fld->element) == INTEGER_CST)
     {
       flen = fold_convert (bitsizetype, TYPE_SIZE (fld->type));
-      fpos = size_binop (MULT_EXPR, flen, fld->element);
+      fpos = fold_convert (bitsizetype, fld->element);
+      fpos = size_binop (MULT_EXPR, flen, fpos);
     }
   else
     gcc_unreachable ();

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-- 
Alexandre Oliva         http://www.lsd.ic.unicamp.br/~oliva/
FSF Latin America Board Member         http://www.fsfla.org/
Red Hat Compiler Engineer   aoliva@{redhat.com, gcc.gnu.org}
Free Software Evangelist  oliva@{lsd.ic.unicamp.br, gnu.org}