[Bug target/33236] New: -minimal-toc register should be psedu-register

pinskia at gcc dot gnu dot org gcc-bugzilla@gcc.gnu.org
Wed Aug 29 18:34:00 GMT 2007


If -minimal-toc is used with a leaf function (that uses global memory), the
register r31 is saved/restored which causes a LHS store on the Cell's PowerPC
side.
Simple example:
int i;
int f(void)
{
  return i;
}
asm:
        std 30,-16(1)
        ld 30,.LCTOC0@toc(2)
        ld 9,.LC0-.LCTOC1(30)
        lwz 3,0(9)
        ld 30,-16(1)  <--- LHS because this is most likely within 50 cycles
        blr


-- 
           Summary: -minimal-toc register should be psedu-register
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P3
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pinskia at gcc dot gnu dot org
GCC target triplet: powerpc64-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33236



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