[Bug tree-optimization/20204] [4.0 regression] miscompilation of asm-declared registers

[dnovillo at gcc dot gnu dot org]

------- Additional Comments From dnovillo at gcc dot gnu dot org  2005-02-25 16:48 -------
(In reply to comment #9)
> I've confirmed on this other machine that the update caused the same breakage.
> 
Ah, yes.  I see it now.  The reorg tickled a bug in the renamer:

# n_21 = V_MUST_DEF <n_18>
n = D.1158_28
...
n_48 = PHI <n_37, n21>
<L2>:
...
# VUSE <n_21>
n.5_40 = n;


That's wrong.  The last VUSE should be VUSE <n_48>.  Virtual operands should
always be in FUD-chain form.

Working on a fix.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |dnovillo at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20204