[Bug target/36223] IV-opt is not optimal for mips

[pinskia at gcc dot gnu dot org]

------- Comment #2 from pinskia at gcc dot gnu dot org  2008-05-12 19:09 -------
Actually this is an IV-opt issue rather than a RA/PRE issue.
For GCC 4.1.1 targeting an internal PPC port, I get the following on the tree
level at the end:
<L1>:;
  D.2011 = (long int *) ivtmp.92;
  MEM[base: &AA, index: D.2011] = MEM[base: &A, index: D.2011];
  MEM[base: &BB, index: D.2011] = MEM[base: &B, index: D.2011];
  ivtmp.92 = ivtmp.92 + 4B;
  if (ivtmp.92 != 2044B) goto <L1>; else goto <L49>;

Which should show that this is IV-opts issue rather than a PRE issue at all.


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|rtl-optimization            |target
            Summary|bad interaction between     |IV-opt is not optimal for
                   |PRE/register                |mips
                   |allocation/reload           |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36223