Re: [PATCH 0/3] pipeline: extend the IPv6 support

[Thomas Monjalon <thomas@monjalon.net>]

13/02/2024 17:57, Cristian Dumitrescu:
> So far, the pipeline supports the following operations on IPv6 addresses:
> -using an IPv6 address as a table match field of exact/ternary/LPM match type
> -assignment of IPv6 address to another IPv6 address
> -conversion between an IPv4 address and an IPv6 address
> 
> The reason for this limited support is the fact that CPUs have 64-bit registers,
> so supporting operations on 128-bit variables requires additional logic.
> 
> We are now adding support for the following operations involving IPv6 addresses:
> -logic operations: AND, OR, XOR
> -shift left/right
> -equality/inequality tests
> 
> The way we do this is by introducing a new instruction (called "movh") to read
> and write the upper half of a 128-bit operand and optimizing the existing
> instruction (called "mov"). This way, we can split an IPv6 address into its
> upper half and lower half and use the existing 64-bit instructions to handle the
> required operations.
> 
> We are still not supporting the following operations on IPv6 addresses, as they
> seem of very little practical use: addition, subtraction, multiplication and
> division.
> 
> Cristian Dumitrescu (3):
>   pipeline: add new instruction for upper half of IPv6 address
>   pipeline: optimize conversion between IPv4 and IPv6 addresses
>   examples/pipeline: add example for IPv6 address swap

Applied, thanks.