This is the mail archive of the
gcc-bugs@gcc.gnu.org
mailing list for the GCC project.
[Bug target/36686] [4.3 regression] qt-4.3.4 compile failure with message "unable to find a register to spill in class 'R0_REGS'"
- From: "kkojima at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: 2 Jul 2008 03:47:40 -0000
- Subject: [Bug target/36686] [4.3 regression] qt-4.3.4 compile failure with message "unable to find a register to spill in class 'R0_REGS'"
- References: <bug-36686-16403@http.gcc.gnu.org/bugzilla/>
- Reply-to: gcc-bugzilla at gcc dot gnu dot org
------- Comment #5 from kkojima at gcc dot gnu dot org 2008-07-02 03:47 -------
Thanks for the updated testcase. I've confirmed that this PR is
a duplicate of PR36684 as you suggested.
> Is this a workaround or right fix ?
SH backend enables first insn scheduling pass for SH4 when
the estimated R0 register pressure is low. PR36684 reveals that
it doesn't work well for PIC which will make many implicit R0 uses.
It seems that there is no easy way to compute accurate R0 register
pressure in that case. Also this optimization doesn't make much
difference in performance for such case. So disabling it for PIC
would be a reasonable fix, I guess. I'll prepare such patch for
PR36684.
*** This bug has been marked as a duplicate of 36684 ***
--
kkojima at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|WAITING |RESOLVED
Keywords| |ice-on-valid-code
Known to fail| |4.3.1 4.4.0
Resolution| |DUPLICATE
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36686