On 12/16/22 18:44, 钟居哲 wrote:
Yes, VNx4DF only has 4 bit in mask mode in case of load and store.
For example vlm or vsm we will load store 8-bit ??? (I am not sure
hardward can load store 4bit,but I am sure it definetly not load store
the whole register size)
Most likely than not you end up loading a larger quantity with the high
bits zero'd. Interesting that we're using a packed model. I'd been
told it was fairly expensive to implement in hardware relative to teh
cost of implementing the sparse model.
So ideally it should be model more accurate. However, since GCC assumes
that 1 BOOL is 1-byte, the only thing I do is to model mask mode as
smallest as possible.
Maybe in the future, I can support 1BOOL for 1-bit?? I am not sure since
it will need to change GCC framework.
I'm a bit confused by this. GCC can support single bit bools, though
ports often extend them to 8 bits or more for computational efficiency
purposes. At least that's the case in general. Is there something
particularly special about masks & bools that's causing problems?
Jeff
