gas encodes "pmovskb %mm7,%eax" wrong

[Robboy, David G]

This is an old bug report that I sent to gcc.gnu.org many months ago, and
just got a notice that I should send it to this recipient.
The instruction "pmovskb %mm7,%eax" generates the binary machine code: 0f d7
f8. This instruction actually moves some mmx register to edi, not to eax
How-To-Repeat: Try stepping through this code and see what happens to edi.
xorl %eax,%eax
movd %eax,%mm7
movl $0xff,%eax
movl $0xff,%edi
pmovmskb %mm7,%eax