feat: graceful shutdown

include/difftest.hpp

@@ -17,6 +17,8 @@ private:
   // target used for read_reg, write_reg, read_mem, write_mem
   Target *current_target = &dut;
 
+  bool exec(size_t n, gdb_action_t *ret);
+
 public:
   Difftest(Target &&dut, std::vector<Target> &&refs);
 
@@ -32,12 +34,13 @@ public:
   bool set_bp(size_t addr, bp_type_t type);
   bool del_bp(size_t addr, bp_type_t type);
 
+  bool check_all();
+
   arch_info_t get_arch() const {
     std::cout << dut.arch.reg_num << std::endl;
     return dut.arch;
   }
 
-  // Other APi
   static bool check(Target &dut, Target &ref) {
     for (int r = 0; r < dut.arch.reg_num; r++) {
       size_t regdut = 0, regref = 0;
@@ -51,7 +54,6 @@ public:
     }
     return true;
   };
-  bool check_all();
 
   class Iterator {
   private:

src/difftest.cpp

@@ -1,6 +1,7 @@
 #include "api.hpp"
 #include <difftest.hpp>
 #include <fstream>
+#include <gdbstub.h>
 #include <stdexcept>
 
 #include <cstdio>
@@ -49,9 +50,9 @@ bool Difftest::check_all() {
   return true;
 }
 
-gdb_action_t Difftest::stepi() {
+bool Difftest::exec(size_t n, gdb_action_t *ret) {
   bool breakflag = false;
-  Target *pbreak;
+  Target *pbreak = &(*(this->begin()));
   for (auto it = this->begin(); it != this->end(); ++it) {
     auto &target = *it;
     target.ops.stepi(target.args.data(), &target.last_res);
@@ -62,37 +63,26 @@ gdb_action_t Difftest::stepi() {
   }
 
   if (breakflag) {
-    gdb_action_t ret = {.reason = gdb_action_t::ACT_BREAKPOINT};
-    pbreak->ops.read_reg(pbreak->args.data(), 32, &ret.data);
-    return ret;
+    ret->reason = pbreak->last_res.reason;
+    ret->data = pbreak->last_res.data;
+    return false;
   }
-  return {gdb_action_t::ACT_NONE, 0};
+  return true;
+}
+
+gdb_action_t Difftest::stepi() {
+  gdb_action_t ret = {.reason = gdb_action_t::ACT_NONE};
+  exec(1, &ret);
+  check_all();
+  return ret;
 }
 
 gdb_action_t Difftest::cont() {
-  bool breakflag = false;
-  Target *pbreak;
-  while (true) {
-    // for(auto &target : *this) {
-    for (auto it = this->begin(); it != this->end(); ++it) {
-      auto &target = *it;
-      target.ops.stepi(target.args.data(), &target.last_res);
-
-      if (target.is_on_breakpoint()) {
-        breakflag = true;
-        pbreak = &target;
-      }
-    }
-
+  gdb_action_t ret = {.reason = gdb_action_t::ACT_NONE};
+  while (exec(1, &ret)) {
     check_all();
-
-    if (breakflag) {
-      gdb_action_t ret = {.reason = gdb_action_t::ACT_BREAKPOINT};
-      pbreak->ops.read_reg(pbreak->args.data(), 32, &ret.data);
+  };
   return ret;
-    }
-  }
-  return {gdb_action_t::ACT_NONE, 0};
 }
 
 int Difftest::read_reg(int regno, size_t *value) {

src/loader.cpp

@@ -1,6 +1,7 @@
 #include "api.hpp"
 #include <cstdint>
 #include <dlfcn.h>
+#include <gdbstub.h>
 #include <iostream>
 #include <stdexcept>
 
@@ -70,7 +71,8 @@ bool Target::is_on_breakpoint(const gdb_action_t &res) const {
   if (res.reason == gdb_action_t::ACT_BREAKPOINT ||
       res.reason == gdb_action_t::ACT_RWATCH ||
       res.reason == gdb_action_t::ACT_WATCH ||
-      res.reason == gdb_action_t::ACT_WWATCH) {
+      res.reason == gdb_action_t::ACT_WWATCH ||
+      res.reason == gdb_action_t::ACT_SHUTDOWN) {
     return true;
   }
   return false;

src/main.cpp

@@ -13,12 +13,12 @@ int main(int argc, char **argv) {
     return ret;
 
   std::vector<Target> refs;
-  Target dut = Target{"dut", "nemu_", config.dut};
+  Target *dut = new Target{"dut", "nemu_", config.dut};
   for (const auto &ref_libpath : config.refs) {
     refs.emplace_back(ref_libpath.string(), "nemu_", ref_libpath);
   }
 
-  Difftest difftest{std::move(dut), std::move(refs)};
+  Difftest difftest{std::move(*dut), std::move(refs)};
 
   difftest.setup(config.memory_file);