Hello David,

On 3/16/2026 5:20 PM, David Laight wrote:

quoted

Introduce runtime_const_mask_32 to further optimize the mask operation
in the futex hash computation hot path. GCC generates a:

  movz  w1, #lo16, lsl #0     // w1 = bits [15:0]
  movk  w1, #hi16, lsl #16    // w1 = full 32-bit value
  and   w0, w0, w1          // w0 = w0 & w1

I don't thing the '&' needs to be part of the asm block.
Just generate the 32bit constant and do the mask in C.
That will let the compiler schedule the instructions.
It also make the code patching more generally useful.

Ack! That makes sense. I'll update it in the next version.
Thank you for taking a look at the series.

-- 
Thanks and Regards,
Prateek