[Bug target/106536] New: P9: gcc does not detect setb pattern

[jens.seifert at de dot ibm.com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106536

            Bug ID: 106536
           Summary: P9: gcc does not detect setb pattern
           Product: gcc
           Version: 11.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jens.seifert at de dot ibm.com
  Target Milestone: ---

int compare2(unsigned long long a, unsigned long long b)
{
    return (a > b ? 1 : (a < b ? -1 : 0));
}

Output:
_Z8compare2yy:
        cmpld 0,3,4
        bgt 0,.L5
        mfcr 3,128
        rlwinm 3,3,1,1
        neg 3,3
        blr
.L5:
        li 3,1
        blr
        .long 0
        .byte 0,9,0,0,0,0,0,0

clang generates:

_Z8compare2yy:                          # @_Z8compare2yy
        cmpld   3, 4
        setb 3, 0
        extsw 3, 3
        blr
        .long   0
        .quad   0