Merge pull request #46 from bdunahu/bdunahu

 Ensure all stages only do work if they are not 'OK' 

1 files changed, 40 insertions, 19 deletions

diff --git a/src/sim/stage.cc b/src/sim/stage.cc
index be69d77..2857e1f 100644
--- a/src/sim/stage.cc
+++ b/src/sim/stage.cc
@@ -7,8 +7,7 @@ Stage::Stage(Stage *next)
 {
 	this->next = next;
 	this->curr_instr = nullptr;
-	this->status = OK;
-	this->checked_out = {};
+	this->status = WAIT;
 }
 
 Stage::~Stage() { delete this->next; };
@@ -21,32 +20,36 @@ Storage *Stage::storage;
 bool Stage::is_pipelined;
 int Stage::clock_cycle;
 
-bool Stage::get_condition(CC c) {
-	return (this->gprs[3] >> c) & 1;
-}
-
-void Stage::set_pc(unsigned int pc) {
-	this->pc = pc;
-}
+bool Stage::get_condition(CC c) { return (this->gprs[3] >> c) & 1; }
 
 InstrDTO *Stage::advance(Response p)
 {
 	InstrDTO *r = nullptr;
+	InstrDTO *s = nullptr;
 	Response n;
 
-	this->advance_helper();
-	if (this->status == OK && this->curr_instr != nullptr && p == OK) {
+	// std::cout << "advance: " << this->id << ": " << this->curr_instr << "?: " << p << ": " << this->checked_out.size() << ": ";
+	// if (curr_instr)
+	// 	std::cout << curr_instr->get_mnemonic();
+	// for (long unsigned int i = 0; i < this->checked_out.size(); ++i)
+	// 	std::cout << this->checked_out[i] << " ";
+	// std::cout << std::endl;	
+	if (this->curr_instr && this->status != OK) {
+		this->advance_helper();
+	}
+	if (this->status == OK && p == WAIT && this->curr_instr) {
 		// mutual consent
 		this->curr_instr->set_time_of(this->id, this->clock_cycle);
 		r = new InstrDTO(*this->curr_instr);
 		delete curr_instr;
 		curr_instr = nullptr;
-		this->status = STALLED;
+		this->status = WAIT;
 	}
 
-	n = (p != OK || this->status != OK) ? STALLED : OK;
-	// the power of consent
-	this->curr_instr = this->next->advance(n);
+	n = (p != WAIT || this->status != WAIT) ? STALLED : WAIT;
+	s = this->next->advance(n);
+	if (s)
+		this->curr_instr = s;
 	return r;
 }
 
@@ -73,16 +76,34 @@ signed int Stage::dereference_register(signed int v)
 	return r;
 }
 
+void Stage::store_register(signed int v, signed int d)
+{
+	if (v < 0 || v >= GPR_NUM + V_NUM) {
+		throw std::out_of_range(string_format(
+			"instruction tried to access register %d, which does "
+			"not exist",
+			v));
+	}
+
+	if (v >= GPR_NUM)
+		this->vrs[v % GPR_NUM] = d;
+	else
+		this->gprs[v] = d;
+}
+
 bool Stage::is_checked_out(signed int r)
 {
 	return std::find(this->checked_out.begin(), this->checked_out.end(), r) !=
 		   this->checked_out.end();
 }
 
-void Stage::squash(){
-	this->curr_instr->set_mnemonic(NOP);
-	this->status = OK;
-	if(this->next){
+void Stage::squash()
+{
+	if (curr_instr) {
+		this->curr_instr->set_mnemonic(NOP);
+		this->status = OK;
+	}
+	if (this->next) {
 		this->next->squash();
 	}
 }