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References: <bug-18908-2744@http.gcc.gnu.org/bugzilla/>
Subject: [Bug middle-end/18908] Missed folding opportunities with bools
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From: "rguenth at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
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------- Comment #11 from rguenth at gcc dot gnu dot org  2008-04-30 19:26 -------
On the trunk we have:

f1 (const _Bool * p)
{
<bb 2>:
  return (_Bool) ((int) *p & 1);

f2 (const _Bool * p)
{
<bb 2>:
  return *p;

f3 (_Bool * p)
{
<bb 2>:
  *p = (_Bool) !*p;

f4 (_Bool * p)
{
<bb 2>:
  *p = 1;

where i686 assembly looks good for all cases.

Still f4 looks weird (wrong-code?!) as we fold *p = ~*p to *p = (int) *p != -1;
I'll open a PR for this.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18908