1 files changed, 59 insertions, 0 deletions
diff --git a/src/if.cc b/src/if.cc
new file mode 100644
index 0000000..0f622d4
--- /dev/null
+++ b/src/if.cc
@@ -0,0 +1,59 @@
+// 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 "if.h"
+#include "instrDTO.h"
+#include "response.h"
+#include "stage.h"
+
+InstrDTO *IF::advance(Response p)
+{
+	InstrDTO *r = nullptr;
+
+	this->advance_helper();
+	if (this->curr_instr != nullptr && p == READY) {
+		// don't increment PC if the PC was just set by wb
+		if (this->curr_instr->is_squashed != 1)
+			++this->pc;
+		r = new InstrDTO(*this->curr_instr);
+		delete curr_instr;
+		curr_instr = nullptr;
+	}
+
+	return r;
+}
+
+void IF::advance_helper()
+{
+	Response r;
+	int i;
+	signed int bits;
+
+	if (this->curr_instr == nullptr && (this->is_pipelined || this->is_empty)) {
+		i = this->storage->read_word(this, this->pc, bits);
+		r = i ? OK : STALLED;
+		if (r == OK) {
+			this->curr_instr = new InstrDTO();
+			this->curr_instr->slot_A = bits;
+			this->curr_instr->slot_B = this->pc;
+			this->curr_instr->is_squashed = 0;
+			this->curr_instr->checked_out = -1;
+			this->curr_instr->mnemonic = ADD;
+			this->is_empty = false;
+		}
+	}
+}