Add Zicfiss extension from CFI extension, v0.4.0

1. Add EXT_ZICFISS for enable Zicfiss with zicfiss extension name.
2. Add new software exception with tval 3 for shadow stack.
3. Implement sspush_x1/sspush_x5/sspopchk_x1/sspopchk_x5/ssrdp/ssamoswap_w/ssamoswap_d.
4. Implement c_sspush_x1/c_sspopchk_x5 in c_lui.h which has same encoding.
5. Add new special access type ss_access in xlate_flags_t for checking special read/write permission in SS(Shadow Stack) page.
6. Add new ss_load/ss_store/ssamoswap to enable ss_access flag.
7. Check special pte(xwr=010) of SS page.

1 files changed, 10 insertions, 0 deletions

diff --git a/riscv/csrs.cc b/riscv/csrs.cc
index 4a612e5..2bd8b0d 100644
--- a/riscv/csrs.cc
+++ b/riscv/csrs.cc
@@ -1757,3 +1757,13 @@ bool hvip_csr_t::unlogged_write(const reg_t val) noexcept {
   state->mip->write_with_mask(MIP_VSSIP, val); // hvip.VSSIP is an alias of mip.VSSIP
   return basic_csr_t::unlogged_write(val & (MIP_VSEIP | MIP_VSTIP));
 }
+
+ssp_csr_t::ssp_csr_t(processor_t* const proc, const reg_t addr, const reg_t mask, const reg_t init):
+  masked_csr_t(proc, addr, mask, init) {
+}
+
+void ssp_csr_t::verify_permissions(insn_t insn, bool write) const {
+  masked_csr_t::verify_permissions(insn, write);
+  DECLARE_XENVCFG_VARS(SSE);
+  require_envcfg(SSE);
+}