Re: [PATCH 0/6] Add several Power ISA 3.1 32/64-bit vector instructions

[Richard Henderson]

On 6/12/20 9:20 PM, Lijun Pan wrote:
> This patch series add several newly introduced 32/64-bit vector
> instructions in Power ISA 3.1. The newly added instructions are
> flagged as ISA300 temporarily in vmx-ops.inc.c and vmx-impl.inc.c
> to make them compile and function since Power ISA 3.1, together
> with next generation processor, has not been fully enabled in QEMU
> yet. When Power ISA 3.1 and next generation processor are fully
> supported, the flags should be changed.

This is not the correct procedure.

Step 1 is to add a new define for ISA301, which is not enabled for any 
processor.

Step 2 is to add all of the new instructions, using ISA301.  In this way there
is no intermediate point in which a 3.01 instruction is enabled for 3.00.  In
addition, we do not have extra churn simply to change the ISA.

Step 3 is to add a new processor for which ISA301 is set.  It is often
reasonable to have a fake processor named "max" that contains all of the
available features.  For ppc, I see that "max" is currently aliased to 
"7400_v2.9".


r~