Introduce a couple of new CET intrinsics for reading and updating a
shadow stack pointer (_get_ssp and _inc_ssp). They replace the existing
_rdssp[d|q] and _incssp[d|q] instrinsics.
PR target/84239
* gcc/config/i386/cetintrin.h: Remove _rdssp[d|q] and
add _get_ssp intrinsics. Remove argument from
__builtin_ia32_rdssp[d|q].
* gcc/config/i386/i386-builtin-types.def: Add UINT_FTYPE_VOID.
* gcc/config/i386/i386-builtin.def: Remove argument from
__builtin_ia32_rdssp[d|q].
* gcc/config/i386/i386.c: Use UINT_FTYPE_VOID. Use
ix86_expand_special_args_builtin for _rdssp[d|q].
* gcc/config/i386/i386.md: Remove argument from rdssp[si|di] insn.
Clear register before usage.
* doc/extend.texi: Remove argument from __builtin_ia32_rdssp[d|q].
Add documentation for new _get_ssp and _inc_ssp intrinsics.
* testsuite/gcc.target/i386/cet-intrin-3.c: Use new _get_ssp and
_inc_ssp intrinsics.
* testsuite/gcc.target/i386/cet-intrin-4.c: Likewise.
* testsuite/gcc.target/i386/cet-rdssp-1.c: Remove argument from
__builtin_ia32_rdssp[d|q].
* libgcc/config/i386/shadow-stack-unwind.hi (_Unwind_Frames_Extra):
Use new _get_ssp and _inc_ssp intrinsics.
From-SVN: r257660
