Merge pull request #1316 from YenHaoChen/pr-native-triggers

implement Debug Specification Section 5.4 Native Triggers

riscv/triggers.cc

@@ -106,6 +106,21 @@ bool trigger_t::textra_match(processor_t * const proc) const noexcept
   return true;
 }
 
+bool trigger_t::allow_action(const state_t * const state) const
+{
+  if (get_action() == ACTION_DEBUG_EXCEPTION) {
+    const bool mstatus_mie = state->mstatus->read() & MSTATUS_MIE;
+    const bool sstatus_sie = state->sstatus->read() & MSTATUS_SIE;
+    const bool vsstatus_sie = state->vsstatus->read() & MSTATUS_SIE;
+    const bool medeleg_breakpoint = (state->medeleg->read() >> CAUSE_BREAKPOINT) & 1;
+    const bool hedeleg_breakpoint = (state->hedeleg->read() >> CAUSE_BREAKPOINT) & 1;
+    return (state->prv != PRV_M || mstatus_mie) &&
+           (state->prv != PRV_S || state->v || !medeleg_breakpoint || sstatus_sie) &&
+           (state->prv != PRV_S || !state->v || !medeleg_breakpoint || !hedeleg_breakpoint || vsstatus_sie);
+  }
+  return true;
+}
+
 reg_t disabled_trigger_t::tdata1_read(const processor_t * const proc) const noexcept
 {
   auto xlen = proc->get_xlen();
@@ -212,7 +227,7 @@ std::optional<match_result_t> mcontrol_common_t::detect_memory_access_match(proc
     value &= 0xffffffff;
   }
 
-  if (simple_match(xlen, value)) {
+  if (simple_match(xlen, value) && allow_action(proc->get_state())) {
     /* This is OK because this function is only called if the trigger was not
      * inhibited by the previous trigger in the chain. */
     hit = true;
@@ -289,7 +304,7 @@ void mcontrol6_t::tdata1_write(processor_t * const proc, const reg_t val, const
 
 std::optional<match_result_t> icount_t::detect_icount_match(processor_t * const proc) noexcept
 {
-  if (!common_match(proc))
+  if (!common_match(proc) || !allow_action(proc->get_state()))
     return std::nullopt;
 
   std::optional<match_result_t> ret = std::nullopt;
@@ -389,7 +404,7 @@ std::optional<match_result_t> trap_common_t::detect_trap_match(processor_t * con
   bool interrupt = (t.cause() & ((reg_t)1 << (xlen - 1))) != 0;
   reg_t bit = t.cause() & ~((reg_t)1 << (xlen - 1));
   assert(bit < xlen);
-  if (simple_match(interrupt, bit)) {
+  if (simple_match(interrupt, bit) && allow_action(proc->get_state())) {
     hit = true;
     return match_result_t(TIMING_AFTER, action);
   }

riscv/triggers.h

@@ -90,6 +90,7 @@ public:
 protected:
   static action_t legalize_action(reg_t val, reg_t action_mask, reg_t dmode_mask) noexcept;
   bool common_match(processor_t * const proc) const noexcept;
+  bool allow_action(const state_t * const state) const;
   reg_t tdata2;
 
   bool vs = false;