[PATCH] powerpc: New feature - HWCAP/HWCAP2 bits in the TCB

[Szabolcs Nagy]

On 08/06/15 22:03, Carlos Eduardo Seo wrote:
> The proposed patch adds a new feature for powerpc. In order to get
> faster access to the HWCAP/HWCAP2 bits, we now store them in the TCB.
> This enables users to write versioned code based on the HWCAP bits
> without going through the overhead of reading them from the auxiliary
> vector.

i assume this is for multi-versioning.

i dont see how the compiler can generate code to access the
hwcap bits currently (without making assumptions about libc
interfaces).

> A new API is published in ppc.h for get/set the bits in the
> aforementioned memory area (mainly for gcc to use to create builtins).

how can the compiler use ppc.h? will it replicate the
offset logic instead?

if hwcap is useful abi between compiler and libc
then why is this done in a powerpc specific way?