On Tue, Mar 3, 2015 at 9:34 AM, Catalin Marinas <[email protected]> wrote: > > Do you mean the cmpxchg_double() change? Becuase %w0 and %0 is the same > physical register. You set it to 0 and immediately override it with > ldxp. >
Thanks Catalin. I realized the blunder a while after Will pointed it out. The asm here was a bit confusing. %0 usually refers to the first input/output variable. But for ldxp instruction(which is just a double-word load, not exclusive), it refers to the physical registers. What about the changes in cmpxchg()? Why do we need to set %w0 to 0 after the ldxrh instruction? Also, could you please point me to any arm64 asm reference? Thanks! -- Pranith -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
