From d7df0c04e78d8f31848fc3f1e590239fbb212225 Mon Sep 17 00:00:00 2001
From: Michael Kuc <mdk3018@ic.ac.uk>
Date: Sat, 23 Nov 2019 21:29:00 +0000
Subject: [PATCH] Improved display code.

Refactored display code into its own function.
---
 src/main.cpp     | 11 +++--------
 src/register.cpp | 18 ++++++++++++++++++
 src/register.hpp |  3 ++-
 3 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/src/main.cpp b/src/main.cpp
index 631215a..b877657 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -25,7 +25,8 @@ int main() {
 		const auto registerState = registerStates[i];
 
 		registers.insert(std::make_pair(i, registerState));
-		std::cout << std::setw(registerIndexPadding) << i << ": " << registerState << "\n";
+		std::cout << std::setw(registerIndexPadding) << i << ": " << registerState << " => ";
+ 		printInstruction(std::cout, registerState) << std::endl;
 	}
 
 	std::cout << std::setw(registerIndexPadding) << i << ": 0...\n\n";
@@ -36,9 +37,9 @@ int main() {
 	while (executing) {
 		std::cout << "L" << pc << "\t";
 		Register instruction = getOrDefault(registers, pc);
+		printInstruction(std::cout, instruction) << std::endl;
 
 		if (instruction == 0) { /* HALT instruction. */
-			std::cout << "HALT" << std::endl;
 			executing = false;
 			continue;
 		}
@@ -49,9 +50,6 @@ int main() {
 			RegIndex sourceRegisterIndex = splitInstruction.first.get_ui();
 			RegIndex destinationLabel = splitInstruction.second.get_ui();
 
-			std::cout << "R" << sourceRegisterIndex << u8"\u207a \u21a3 " << destinationLabel
-			          << "\n";
-
 			getOrDefault(registers, sourceRegisterIndex)++;
 			pc = destinationLabel;
 		} else {
@@ -61,9 +59,6 @@ int main() {
 			RegIndex trueLabel = branches.first.get_ui();
 			RegIndex falseLabel = branches.second.get_ui();
 
-			std::cout << "R" << sourceRegisterIndex << "\u207b \u21a3 " << trueLabel << ", "
-			          << falseLabel << "\n";
-
 			auto& sourceRegister = getOrDefault(registers, sourceRegisterIndex);
 
 			if (sourceRegister > 0) {
diff --git a/src/register.cpp b/src/register.cpp
index 1da8f93..bdc8c7f 100644
--- a/src/register.cpp
+++ b/src/register.cpp
@@ -1,4 +1,5 @@
 #include "register.hpp"
+#include <iostream>
 
 template <>
 std::pair<Register, Register> toPair<false>(Register unsplit) {
@@ -41,3 +42,20 @@ std::vector<Register> toList(Register unsplit) {
 
 	return list;
 }
+
+std::ostream& printInstruction(std::ostream& sout, Register instruction) {
+	if (instruction == 0)
+		return sout << "BREAK";
+
+	const auto splitInstruction = toPair<false>(instruction);
+	const auto command = splitInstruction.first / 2;
+
+	if (splitInstruction.first % 2 == 0) {
+		/* We have an increment instruction, so second parameter is just label. */
+			return sout << "R" << command << "\u207a \u21a3 " << splitInstruction.second;
+	}
+
+	const auto labels = toPair<true>(splitInstruction.second);
+
+	return sout << "R" << command << "\u207b \u21a3 " << labels.first << ", " << labels.second;
+}
diff --git a/src/register.hpp b/src/register.hpp
index 5acf69c..f04e407 100644
--- a/src/register.hpp
+++ b/src/register.hpp
@@ -4,11 +4,12 @@
 #include <gmpxx.h>
 #include <utility>
 #include <vector>
+#include <ios>
 
 using Register = mpz_class;
 using RegIndex = uint16_t;
 
 template <bool mapZero>
 std::pair<Register, Register> toPair(Register unsplit);
-
 std::vector<Register> toList(Register unsplit);
+std::ostream& printInstruction(std::ostream& sout, Register instruction);