[Bug rtl-optimization/19210] New: [4.0 Regression] not using do-loop for some loops

[pinskia at gcc dot gnu dot org]

Take following loop:
int a[220000];
void 
f (int n)
{
  int k;
  for(k = 3;k <= n;k++) {
    a[k] = k;
  }
}

On the mainline we produce:
L4:
        stw r9,0(r2)
        addi r9,r9,1
        cmpw cr7,r3,r9
        addi r2,r2,4
        bge+ cr7,L4

But with 3.3.2, we use bdnz:
L9:
        slwi r3,r11,2
        stwx r11,r3,r9
        addi r11,r11,1
        bdnz L9

-- 
           Summary: [4.0 Regression] not using do-loop for some loops
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: minor
          Priority: P2
         Component: rtl-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pinskia at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org
GCC target triplet: powerpc-darwin


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19210