feat(npc): ebreak support through external inst matching

npc/include/components.hpp

@@ -79,5 +79,8 @@ public:
     // printf("waddr: 0x%x\n", waddr);
     mem[addr_to_index((uint32_t)waddr)] = expand_bits(wmask) & wdata;
   }
+  void *guest_to_host(std::size_t addr) {
+    return mem.data() + addr_to_index(addr);
+  }
 };
 #endif

npc/include/trm_difftest.hpp

@@ -34,19 +34,29 @@ struct DifftestTrmInterface : public TrmInterface {
       fetch_state();
     };
     exec = [this](uint64_t n) {
-      while (n--) {
+      bool enable_disasm = true;
+      if (n > 30) {
+        enable_disasm = false;
+      }
 
+      while (n--) {
         word_t pc = this->ref.at("pc");
         word_t inst = this->ref.at(pc);
-        std::cout << d.disassemble(pc, (uint8_t *)&inst, WORD_BYTES)
-                  << std::endl;
+        if (enable_disasm)
+          std::cout << d.disassemble(pc, (uint8_t *)&inst, WORD_BYTES)
+                    << std::endl;
+        if (inst == 1048691) {
+          // ebreak
+          throw TrmRuntimeException(TrmRuntimeException::EBREAK, "ebreak");
+        }
         this->ref.exec(1);
         this->dut.exec(1);
         this->ref.fetch_state();
         this->dut.fetch_state();
         if (*(CPUState *)this->ref.cpu_state !=
             *(CPUState *)this->dut.cpu_state) {
-          throw std::runtime_error("Difftest failed");
+          throw TrmRuntimeException(TrmRuntimeException::DIFFTEST_FAILED,
+                                    "Difftest failed");
         }
       }
     };

npc/include/trm_interface.hpp

@@ -96,6 +96,21 @@ public:
   virtual void print(std::ostream &os) const = 0;
 };
 
+class TrmRuntimeException : public std::exception {
+private:
+  const char *msg_;
+  int code_;
+
+public:
+  enum { EBREAK, DIFFTEST_FAILED };
+  TrmRuntimeException(int code, const char *message)
+      : code_(code), msg_(message) {}
+
+  virtual const char *what() const throw() { return msg_; }
+
+  int error_code() const { return code_; }
+};
+
 struct RefTrmInterface : TrmInterface {
   RefTrmInterface(std::filesystem::path lib_file) {
     void *handle = dlopen(lib_file.c_str(), RTLD_LAZY);