On Wed, Jul 24, 2013 at 10:55 AM, Peter Bergner <berg...@vnet.ibm.com> wrote: > On Wed, 2013-07-24 at 10:42 -0700, H.J. Lu wrote: >> Are there any other Linux targets with callee saved vector registers? > > Yes, on POWER. From our ABI: > > On processors with the VMX feature. > v0-v1 Volatile scratch registers > v2-v13 Volatile vector parameters registers > v14-v19 Volatile scratch registers > v20-v31 Non-volatile registers > > I'll note that the new VSX register state we recently added with power7 > were made volatile, but then we already had these non-volatile altivec > regs to use.
How do you save/restore those vector registers for exception? Unwinder in libgcc uses _Unwind_Word to save and restore registers in DWARF unwind frame. It doesn't support anything wider than _Unwind_Word, which is usually smaller than vector register. -- H.J.
