------- 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