[PATCH v2] RISC-V: Add vector registers to __SYSCALL_CLOBBERS

[Peter Bergner]

On 9/3/25 3:52 PM, Peter Bergner wrote:
> Here's an updated patch that takes Palmer's suggestions into account.
> 
> Differences from v1:
> * Added vl, vtype, vxrm, and vxsat registers.
> * Added preconfigure fragment to disallow GCC 14 or earlier when
>   vector is enabled and only allow RVV 1.0 or later.
> 
> The vl, vtype, vxrm, and vxsat registers all exist in GCC 15 (vxsat was
> added in GCC 15), so we don't need any extra preconfigure checks that
> they exist in old compilers, since we're only allowing the vector
> extension for GCC 15 and later. 
> 
> This was tested with GCC 14 and verified that the preconfigure check
> flags the error.  I then built using GCC 15 with -march=rv64gcv0p7
> and again verified that the preconfigure check flags an error.
> I then built with GCC 15 using -march=rv64gc & -march=rv64gcv and they
> both showed no build or testsuite regressions to the base build.

With no objections, I pushed this after a rebase, build and regtest
with no regressions.

Peter