* Solaris/x86 /bin/as doesn't support .org, so I've just disabled the
uses in src/x86/{sysv, unix64}.S, as on Darwin.
* Solaris/x86 needs to use EH_FRAME_FLAGS so manually and compiler
generated .eh_frame sections match, otherwise libffi.so fails to link:
* Solaris/x86 /bin/as has different COMDAT syntax; I've disabled it for
the moment.
The unwind info isn't 100% correct at all points during the epilogue,
and not annotating is just as incorrect as the annotation. This works
better on systems that do not support DW_OP_call_frame_cfa.
The Apple assembler defaults to power of two alignment, rather than
byte alignment like everyone else. Force byte alignment by using
the proper directive.
Move everything into sysv.S, removing win32.S and freebsd.S.
Handle all abis with a single ffi_closure_inner function.
Move complexity of the raw THISCALL trampoline into assembly
instead of the trampoline itself.
Only push the context for the REGISTER abi; let the rest
receive it in a register.
Decouple the assembly from FFI_TYPE_*. Merge prep_args with ffi_call,
passing the frame and the stack to the assembly.
Note that this patch isn't really standalone, as this breaks closures.