Arm64: Lift Load-Exclusive/Store-Exclusive instructions (LDXP/STXP, etc.)

[galenbwill]

The following was posted as a comment on another issue, but I'm splitting it out because this case can be lifted more directly (and may or may not involve adding an intrinsic to indicate the "Exclusive" aspect of these instructions). It will also require more thought and effort to implement.

version: 4.2.6325-dev Personal (c3d1ad94)

system: Linux version 6.10.13-3-MANJARO (builduser@fv-az1246-770) (gcc (GCC) 14.2.1 20240910, GNU ld (GNU Binutils) 2.43.0) #1 SMP PREEMPT_DYNAMIC Tue Oct 8 03:24:49 UTC 2024

ffffff93d1868b00                    do

ffffff93d1868b00                    {

🚫ffffff93d1868ae8                        /*   unimplemented  {ldxp x11, x26, [x10]} */

ffffff93d1868aec                        x11 ^= result;

ffffff93d1868af4                        arg4 = x11 | (arg4 ^ x8_6);

ffffff93d1868af4                        

ffffff93d1868af8                        if (arg4)

ffffff93d1868af8                            break;

ffffff93d1868af8                        

🚫ffffff93d1868afc                        /*   unimplemented  {stxp w11, x9, x12, [x10]} */

ffffff93d1868b00                    } while (x11);

also the unimplemented code

Originally posted by @bb33bb in #6062