[Bug target/49547] New: LZCNT should be enabled only if ABM or LZCNT bits are set

[kirill.yukhin at intel dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49547

           Summary: LZCNT should be enabled only if ABM or LZCNT bits are
                    set
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: kirill.yuk...@intel.com


Hi,
according to freshest Specs, we need to enable LZCNT only when ABM or LZCNT
bits of CPUID (leaf 8000_0001h) is set.
However config/i386/i386.md has:

(define_insn "clz<mode>2_abm"
  [(set (match_operand:SWI248 0 "register_operand" "=r")
        (clz:SWI248 (match_operand:SWI248 1 "nonimmediate_operand" "rm")))
   (clobber (reg:CC FLAGS_REG))]
  "TARGET_ABM || TARGET_BMI"
  "lzcnt{<imodesuffix>}\t{%1, %0|%0, %1}"
  [(set_attr "prefix_rep" "1")
   (set_attr "type" "bitmanip")
   (set_attr "mode" "<MODE>")])

There is no connection to BMI anymore.