[Bug target/57688] [4.9 Regression] -O3 -march=native generates illegal opcode on AMD Phenom

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57688

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |FIXED
   Target Milestone|---                         |4.9.0
            Summary|-O3 -march=native generates |[4.9 Regression] -O3
                   |illegal opcode on AMD       |-march=native generates
                   |Phenom                      |illegal opcode on AMD
                   |                            |Phenom

--- Comment #10 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Author: jakub
Date: Sun Jun 23 19:06:00 2013
New Revision: 200352

URL: http://gcc.gnu.org/viewcvs?rev=200352&root=gcc&view=rev
Log:
    PR target/57688
    * common/config/i386/i386-common.c (ix86_handle_option): For OPT_mlzcnt
    add missing return true.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/common/config/i386/i386-common.c

Fixed.  BTW, with explicit -mtbm we still generate:
bextr    $7682, %rdx, %rdx
while without it we generate much more compact:
shrl $2, %rdx
Will create a PR for that.