------- Comment #1 from ramana at gcc dot gnu dot org 2009-12-30 17:32 -------
The problem here essentially appears to be that GCC can't seem to generate
conditional tail-calls (or conditional calls for that matter in this case) with
-fno-optimize-sibling-calls . I don't read this as a problem with
builtin_expect per-se but that of GCC not being able to generate a conditional
tail-call / call.
A simpler test is essentially the following.
void foo (int x)
{
if (x)
bar ();
else
baz ();
}
This is also not just a target problem but probably one for the RTL optimizers
rather any where else..
--
ramana at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Severity|normal |enhancement
Status|UNCONFIRMED |NEW
Component|target |rtl-optimization
Ever Confirmed|0 |1
Last reconfirmed|0000-00-00 00:00:00 |2009-12-30 17:32:59
date| |
Summary|GCC can do less work in the |Generate conditional tail
|frequently executed path |calls .
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42497
