NEON registers about context

[olk]

It was requested by users not to preserve registers s16-s31.

[mofr]

Do you remember why it was requested? And how to deal with it in case of compiler optimizations?
I'm asking because it violates ARMv7 calling conventions and compiler generates "wrong" code in conjunction with boost.context and thread switching.

[olk]

I was told I should remove it because it consumes cycles isn't needed. One year ago boost.context has preserved the FP-env stuff.

[olk]

I would add something like:
#if (defined(VFP_FP) && !defined(SOFTFP))
push {d8-d15}
#endif
...
#if (defined(VFP_FP) && !defined(SOFTFP))
pop {d8-d15}
#endif

[olk]

Could yout test branch fp (https://github.com/boostorg/context/tree/fp) please?
I've no access to a ARM board at the moment.

[mofr]

Unfortunately, I'm using copy-pasted version of boost. However, i've applied your changes into my version and issue has gone.
Thanks for your help and fast replies.

[olk]

Thank you too!

[mofr]

Do you plan to enable such option in future releases?