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.

10 files changed, 54 insertions, 1 deletions

diff --git a/riscv/insns/c_lui.h b/riscv/insns/c_lui.h
index 7a82c13..98a8898 100644
--- a/riscv/insns/c_lui.h
+++ b/riscv/insns/c_lui.h
@@ -5,7 +5,13 @@ if (insn.rvc_rd() == 2) { // c.addi16sp
 } else if (insn.rvc_imm() != 0) { // c.lui
   WRITE_RD(insn.rvc_imm() << 12);
 } else if ((insn.rvc_rd() & 0x11) == 1) { // c.mop.N
-  #include "c_mop_N.h"
+  if (insn.rvc_rd() == 5 && p->extension_enabled(EXT_ZICFISS)) {
+    #include "c_sspopchk_x5.h"
+  } else if (insn.rvc_rd() == 1 && p->extension_enabled(EXT_ZICFISS)) {
+    #include "c_sspush_x1.h"
+  } else {
+    #include "c_mop_N.h"
+  }
 } else {
   require(false);
 }
diff --git a/riscv/insns/c_sspopchk_x5.h b/riscv/insns/c_sspopchk_x5.h
new file mode 100644
index 0000000..d379f2c
--- /dev/null
+++ b/riscv/insns/c_sspopchk_x5.h
@@ -0,0 +1,5 @@
+#include "zicfiss.h"
+
+if (xSSE()) {
+  POP_VALUE_FROM_SS_AND_CHECK(READ_REG(X_T0));
+}
diff --git a/riscv/insns/c_sspush_x1.h b/riscv/insns/c_sspush_x1.h
new file mode 100644
index 0000000..3645a9e
--- /dev/null
+++ b/riscv/insns/c_sspush_x1.h
@@ -0,0 +1,5 @@
+#include "zicfiss.h"
+
+if (xSSE()) {
+  PUSH_VALUE_TO_SS(RA);
+}
diff --git a/riscv/insns/ssamoswap_d.h b/riscv/insns/ssamoswap_d.h
new file mode 100644
index 0000000..10ea5ef
--- /dev/null
+++ b/riscv/insns/ssamoswap_d.h
@@ -0,0 +1,7 @@
+require_extension(EXT_ZICFISS);
+require_extension('A');
+require_rv64;
+
+DECLARE_XENVCFG_VARS(SSE);
+require_envcfg(SSE);
+WRITE_RD(MMU.ssamoswap<uint64_t>(RS1, RS2));
diff --git a/riscv/insns/ssamoswap_w.h b/riscv/insns/ssamoswap_w.h
new file mode 100644
index 0000000..3cdefc7
--- /dev/null
+++ b/riscv/insns/ssamoswap_w.h
@@ -0,0 +1,7 @@
+require_extension(EXT_ZICFISS);
+require_extension('A');
+
+DECLARE_XENVCFG_VARS(SSE);
+require_envcfg(SSE);
+WRITE_RD(sext32(MMU.ssamoswap<uint32_t>(RS1, RS2)));
+
diff --git a/riscv/insns/sspopchk_x1.h b/riscv/insns/sspopchk_x1.h
new file mode 100644
index 0000000..6ea4c22
--- /dev/null
+++ b/riscv/insns/sspopchk_x1.h
@@ -0,0 +1,7 @@
+#include "zicfiss.h"
+
+if (xSSE()) {
+  POP_VALUE_FROM_SS_AND_CHECK(RS1);
+} else {
+  #include "mop_r_N.h"
+}
diff --git a/riscv/insns/sspopchk_x5.h b/riscv/insns/sspopchk_x5.h
new file mode 100644
index 0000000..78218b3
--- /dev/null
+++ b/riscv/insns/sspopchk_x5.h
@@ -0,0 +1 @@
+#include "sspopchk_x1.h"
diff --git a/riscv/insns/sspush_x1.h b/riscv/insns/sspush_x1.h
new file mode 100644
index 0000000..67ad9bb
--- /dev/null
+++ b/riscv/insns/sspush_x1.h
@@ -0,0 +1,7 @@
+#include "zicfiss.h"
+
+if (xSSE()) {
+  PUSH_VALUE_TO_SS(RS2);
+} else {
+  #include "mop_rr_N.h"
+}
diff --git a/riscv/insns/sspush_x5.h b/riscv/insns/sspush_x5.h
new file mode 100644
index 0000000..235333d
--- /dev/null
+++ b/riscv/insns/sspush_x5.h
@@ -0,0 +1 @@
+#include "sspush_x1.h"
diff --git a/riscv/insns/ssrdp.h b/riscv/insns/ssrdp.h
new file mode 100644
index 0000000..20b0856
--- /dev/null
+++ b/riscv/insns/ssrdp.h
@@ -0,0 +1,7 @@
+#include "zicfiss.h"
+
+if (xSSE()) {
+  WRITE_RD(STATE.ssp->read());
+} else {
+  #include "mop_r_N.h"
+}