1 files changed, 119 insertions, 0 deletions
diff --git a/src/stage.cc b/src/stage.cc
new file mode 100644
index 0000000..4efe2fe
--- /dev/null
+++ b/src/stage.cc
@@ -0,0 +1,119 @@
+// Simulator for the RISC-V[ECTOR] mini-ISA
+// Copyright (C) 2025 Siddarth Suresh
+// Copyright (C) 2025 bdunahu
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+#include "stage.h"
+#include <array>
+#include <deque>
+
+Stage::Stage(Stage *next)
+{
+	this->next = next;
+	this->curr_instr = nullptr;
+	this->status = READY;
+}
+
+Stage::~Stage() { delete this->next; };
+
+std::array<int, GPR_NUM> Stage::gprs;
+std::array<int, V_NUM> Stage::vrs;
+std::deque<signed int> Stage::checked_out;
+unsigned int Stage::pc;
+Storage *Stage::storage;
+bool Stage::is_pipelined;
+bool Stage::is_empty;
+int Stage::clock_cycle;
+
+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;
+
+	if (this->curr_instr && this->curr_instr->is_squashed == 1)
+		this->status = OK;
+	if (this->curr_instr && this->status != OK) {
+		this->advance_helper();
+	}
+	if (this->status == OK && p == READY && this->curr_instr) {
+		// mutual consent
+		r = new InstrDTO(*this->curr_instr);
+		delete curr_instr;
+		curr_instr = nullptr;
+		this->status = READY;
+	}
+
+	n = (p != READY || this->status != READY) ? STALLED : READY;
+	s = this->next->advance(n);
+	if (s)
+		this->curr_instr = s;
+	return r;
+}
+
+InstrDTO *Stage::get_instr() { return this->curr_instr; }
+
+void Stage::set_condition(CC c, bool v)
+{
+	if (v)
+		this->gprs[3] = this->gprs[3] | 1 << c;
+	else
+		this->gprs[3] = this->gprs[3] & ~(1 << c);
+}
+
+signed int Stage::dereference_register(signed int v)
+{
+	signed int r;
+
+	if (v < 0 || v >= GPR_NUM + V_NUM) {
+		throw std::out_of_range(
+			"instruction tried to access register which does not exist");
+	}
+
+	r = (v >= GPR_NUM) ? this->vrs[v % GPR_NUM] : this->gprs[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(
+			"instruction tried to access register which does not exist");
+	}
+
+	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()
+{
+	if (curr_instr) {
+		this->curr_instr->is_squashed = 1;
+		this->status = OK;
+	}
+	if (this->next) {
+		this->next->squash();
+	}
+}