queue writes and commit them after an instruction has finished executing

3 files changed, 40 insertions, 7 deletions

diff --git a/emulator.cpp b/emulator.cpp
index 14377ac..565f3cc 100644
--- a/emulator.cpp
+++ b/emulator.cpp
@@ -9,6 +9,13 @@
 #include "program.h"
 #include "register_address.h"
 
+emulator::write::write(
+	register_address addr,
+	value * val) :
+	m_addr(addr),
+	m_val(val)
+	{ }
+
 emulator::emulator(
 	program_loader * loader,
 	int num_temp_regs,
@@ -36,6 +43,11 @@ emulator::run()
 	for(it = p->m_instructions.begin();
 					it < p->m_instructions.end(); ++it) {
 		(*it)->execute(*this);
+		while (!m_write_queue.empty()) {
+			write w = m_write_queue.front();
+			set_value(w.m_addr, w.m_val);
+			m_write_queue.pop();
+		}
 	}
 	return true;
 }
@@ -125,3 +137,11 @@ emulator::get_output_value(unsigned int index)
 	}
 	return m_out_regs[index]->simplify();
 }
+
+void
+emulator::queue_write(
+	register_address addr,
+	value * val)
+{
+	m_write_queue.push(write(addr, val));
+}
diff --git a/emulator.h b/emulator.h
index c3fcd1f..c9ad2e3 100644
--- a/emulator.h
+++ b/emulator.h
@@ -2,6 +2,7 @@
 #ifndef EMULATOR_H_
 #define EMULATOR_H_
 
+#include <queue>
 #include <vector>
 
 #include "value.h"
@@ -21,12 +22,23 @@ public:
 	bool run();
 	void set_constants(float value);
 	value * get_value(register_address addr);
-	void set_value(
+	value * get_output_value(unsigned int index);
+	void queue_write(
 		register_address addr,
 		value * val);
-	value * get_output_value(unsigned int index);
 
 private:
+	class write {
+	public:
+		write(register_address addr, value * val);
+		register_address m_addr;
+		value * m_val;
+	};
+
+	void set_value(
+		register_address addr,
+		value * val);
+
 	program_loader * m_loader;
 	std::vector<value *> m_temp_regs;
 	std::vector<float_value *> m_const_regs;
@@ -34,6 +46,7 @@ private:
 	std::vector<value *> m_private_regs;
 	std::vector<float_value*> m_immediate_regs;
 	std::vector<float_value*> m_input_regs;
+	std::queue<write> m_write_queue;
 };
 
 #endif //EMULATOR_H
diff --git a/instruction.cpp b/instruction.cpp
index 779b397..52dc8ba 100644
--- a/instruction.cpp
+++ b/instruction.cpp
@@ -29,7 +29,7 @@ void instruction::execute(emulator & emulator)
 			l = emulator.get_value(m_src_regs[0][i]);
 			break;
 		}
-		emulator.set_value(m_dst[i],
+		emulator.queue_write(m_dst[i],
 					new tree_value(m_evaluator, l, r));
 	}
 }
@@ -64,7 +64,7 @@ add_instruction::execute(emulator & emulator)
 		tree_value * val = new tree_value(this->m_evaluator,
 				  emulator.get_value(m_src_regs[0][i]),
 				  emulator.get_value(m_src_regs[1][i]));
-		emulator.set_value(m_dst[i], val);
+		emulator.queue_write(m_dst[i], val);
 	}
 }
 
@@ -77,7 +77,7 @@ mov_instruction::execute(emulator & emulator)
 {
 	unsigned int i;
 	for (i = 0; i < m_dst.size(); i++) {
-		emulator.set_value(m_dst[i],
+		emulator.queue_write(m_dst[i],
 				   emulator.get_value(m_src_regs[0][i]));
 	}
 }
@@ -94,7 +94,7 @@ mul_instruction::execute(emulator & emulator)
 		tree_value * val = new tree_value(this->m_evaluator,
 				  emulator.get_value(m_src_regs[0][i]),
 				  emulator.get_value(m_src_regs[1][i]));
-		emulator.set_value(m_dst[i], val);
+		emulator.queue_write(m_dst[i], val);
 	}
 }
 
@@ -112,7 +112,7 @@ mad_instruction::execute(emulator & emulator)
 					emulator.get_value(m_src_regs[1][i]));
 		tree_value * mad = new tree_value(new add_evaluator(),
 				mul, emulator.get_value(m_src_regs[2][i]));
-		emulator.set_value(m_dst[i], mad);
+		emulator.queue_write(m_dst[i], mad);
 	}
 }