[...]
> 
> gcc-4.6 -O1 -ftree-vectorize
> -------------------------------------
> 0x0000000000480991 <+5041>:  mov    %eax,%ecx
> 0x0000000000480993 <+5043>:  sub    %edx,%ecx
> 0x0000000000480995 <+5045>:  mov    %ecx,(%r12,%rax,4)
> 0x0000000000480999 <+5049>:  movzbl 0x0(%rbp,%rax,1),%ecx
> 0x000000000048099e <+5054>:  lea    0x1(%rdx),%esi
> 0x00000000004809a1 <+5057>:  cmp    $0x9,%cl
> 0x00000000004809a4 <+5060>:  cmovne %edx,%esi
> 0x00000000004809a7 <+5063>:  cmove  %esi,%edx
> 0x00000000004809aa <+5066>:  setne  %cl
> 0x00000000004809ad <+5069>:  movzbl %cl,%ecx
> 0x00000000004809b0 <+5072>:  lea    0x1(%rax,%rcx,2),%rax
> 0x00000000004809b5 <+5077>:  cmp    %rax,%rdi
> 0x00000000004809b8 <+5080>:  jg     0x480991 <PyCode_Optimize+5041>
> -------------------------------------

Looks like code generation is borked.
(it lacks a compare to 0x59 or 0x5a (90), and "setne" wouldn't be the
right instruction anyway)