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Date: Tue, 06 Dec 2005 21:07:00 -0000
Subject: [Bug target/25287]  New: PPC has conditional indirect jumps if ra allocates the a in ctr before the jumps
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From: "pinskia at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
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Code:
int f(void *a, int b)
{
  if (b ==1) goto *a;
  g();
  if (b ==2) goto *a;
  g();
  return 1
}

This is very minor but I thought it would be cool if GCC could do something
like:
.f:
        mflr %r0
        cmpwi %cr7,%r4,1
        std %r30,-16(%r1)
        std %r31,-8(%r1)
        mr %r30,%r3
        mr %r31,%r4
        std %r0,16(%r1)
        stdu %r1,-128(%r1)
        mtctr %r30
        beqctr %cr7,.L3
        bl .g
        nop
        cmpwi %cr7,%r31,2
        mtctr %r30
        beqctr %cr7,.L3
        bl .g
        li %r3
        blr
.L3:
        mtctr %r30
        bctr


-- 
           Summary: PPC has conditional indirect jumps if ra allocates the a
                    in ctr before the jumps
           Product: gcc
           Version: 4.2.0
            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=25287