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Assignment/context.h

+struct Context {
+  void *rip, *rsp;
+  void *rbx, *rbp, *r12, *r13, *r14, *r15;
+  };
+  
+extern "C" int get_context(Context *c);
+extern "C" void set_context(Context *c);
+extern "C" void swap_context(Context *out, Context *in);