simplify c++ memory models; support +dramsim flag

works for both vlsi and emulator

csrc/mm.h

@@ -0,0 +1,75 @@
+#ifndef MM_EMULATOR_H
+#define MM_EMULATOR_H
+
+#include "mm_param.h"
+#include <stdint.h>
+#include <queue>
+
+class mm_t
+{
+ public:
+  mm_t() : data(0), size(0) {}
+
+  virtual void init(size_t sz);
+
+  virtual bool req_cmd_ready() = 0;
+  virtual bool req_data_ready() = 0;
+  virtual bool resp_valid() = 0;
+  virtual uint64_t resp_tag() = 0;
+  virtual void* resp_data() = 0;
+
+  virtual void tick
+  (
+    bool req_cmd_val,
+    bool req_cmd_store,
+    uint64_t req_cmd_addr,
+    uint64_t req_cmd_tag,
+    bool req_data_val,
+    void* req_data_bits
+  ) = 0;
+
+  virtual void* get_data() { return data; }
+  virtual size_t get_size() { return size; }
+
+  virtual ~mm_t();
+
+ protected:
+  char* data;
+  size_t size;
+};
+
+class mm_magic_t : public mm_t
+{
+ public:
+  mm_magic_t() : store_inflight(false), store_count(0) {}
+
+  virtual void init(size_t sz);
+
+  virtual bool req_cmd_ready() { return !store_inflight; }
+  virtual bool req_data_ready() { return store_inflight; }
+  virtual bool resp_valid() { return !resp.empty(); }
+  virtual uint64_t resp_tag() { return resp_valid() ? resp.front().first : 0; }
+  virtual void* resp_data() { return resp_valid() ? &resp.front().second[0] : &dummy_data[0]; }
+
+  virtual void tick
+  (
+    bool req_cmd_val,
+    bool req_cmd_store,
+    uint64_t req_cmd_addr,
+    uint64_t req_cmd_tag,
+    bool req_data_val,
+    void* req_data_bits
+  );
+
+ protected:
+  bool store_inflight;
+  int store_count;
+  uint64_t store_addr;
+  std::vector<char> dummy_data;
+
+  uint64_t cycle;
+  std::queue<std::pair<uint64_t, std::vector<char>>> resp;
+};
+
+void load_mem(void* mem, const char* fn);
+#endif