Setting condition code register, overflow guard

1 files changed, 18 insertions, 0 deletions

diff --git a/inc/ex.h b/inc/ex.h
index 2ca8876..4edf873 100644
--- a/inc/ex.h
+++ b/inc/ex.h
@@ -3,6 +3,7 @@
 #include "instrDTO.h"
 #include "response.h"
 #include "stage.h"
+#include <unordered_map>
 
 class EX : public Stage
 {
@@ -15,6 +16,23 @@ class EX : public Stage
 	EX(Stage *next);
 
 	InstrDTO *advance(Response p) override;
+
+  private:
+	/**
+	 * Sets the (over|under)flow condition code if adding `a` and `b` results in
+	 * either.
+	 * @param the first operand
+	 * @param the second operand
+	 */
+	void overflow_guard(signed int a, signed int b);
+	/**
+	 * Maps each mnemonic to a function which carries out the instruction's base
+	 * logic.
+	 */
+	std::unordered_map<
+		Mnemonic,
+		std::function<void(signed int &s1, signed int &s2)>>
+		instr_map;
 };
 
 #endif /* EX_H_INCLUDED */