Yes, Patrick, you were faster :) Seems, we just need to pass 0 as IMM value
On Tue, Feb 21, 2012 at 7:14 PM, Patrick Marlier <patrick.marl...@gmail.com> wrote: > On 02/21/2012 02:52 AM, Uros Bizjak wrote: >> >> On Tue, Feb 21, 2012 at 12:26 AM, Andi Kleen<a...@firstfloor.org> wrote: >>>> >>>> IIUC the documentation, the fallback label is a parameter to xbegin >>>> insn, but the insn itself doesn't jump anywhere - it just records the >>> >>> >>> From the point of view of the program XBEGIN behaves like a conditional >>> jump (with a very complicated and unpredictable condition) >> >> >> Yes, but as it is written ATM, it conditionally jumps to the next insn. >> >> BTW: Looking a bit more to the spec, we can simply write >> >> xbegin $0 >> >> as the spec says that offset is relative to the _NEXT_ instruction. > > > AFAIU, the current binutils 'as' expects a label not an offset. So "xbegin > 0" means fallback at label 0. > -- > Patrick > >
