Add implementation functions for checking out a register.

3 files changed, 66 insertions, 28 deletions

diff --git a/src/sim/id.cc b/src/sim/id.cc
index c6e42d5..e9c48df 100644
--- a/src/sim/id.cc
+++ b/src/sim/id.cc
@@ -5,13 +5,20 @@
 #include "logger.h"
 #include "response.h"
 #include "stage.h"
-#include "utils.h"
-
-static Logger *global_log = Logger::getInstance();
 
 ID::ID(Stage *stage) : Stage(stage) { this->id = DCDE; }
 
-Response ID::advance(InstrDTO &i) { Response r; }
+Response ID::advance(InstrDTO &i)
+{
+	Response r;
+	signed int s1, s2, s3;
+	Mnemonic m;
+
+	s1 = i.get_instr_bits();
+
+	get_instr_fields(s1, s2, s3, m);
+	return r;
+}
 
 // TODO this function is ugly
 void ID::get_instr_fields(
@@ -53,30 +60,10 @@ void ID::split_instr(signed int &raw, unsigned int &type, Mnemonic &m)
 	opcode_size = (type == 0b0) ? R_OPCODE_SIZE : OPCODE_SIZE;
 	opcode = GET_MID_BITS(raw, TYPE_SIZE, TYPE_SIZE + opcode_size);
 	try {
-		m = instr::mnemonic_map.at((opcode << 2) + type);
+		m = instr::mnemonic_map.at((opcode << TYPE_SIZE) + type);
 	} catch (std::out_of_range const &) {
 		m = NOP;
 	}
 
 	raw = (unsigned int)raw >> (TYPE_SIZE + opcode_size);
 }
-
-Response ID::dereference_register(signed int &v)
-{
-	Response r;
-	r = OK;
-
-	if (v < 0 || v >= GPR_NUM + V_NUM) {
-		global_log->log(
-			ERROR, string_format(
-					   "instruction tried to access register %d, which does "
-					   "not exist",
-					   v));
-		exit(EXIT_FAILURE);
-	} else if (v >= GPR_NUM)
-		v = this->vrs[v % GPR_NUM];
-	else
-		v = this->gprs[v];
-
-	return r;
-}
diff --git a/src/sim/instrDTO.cc b/src/sim/instrDTO.cc
index 7864eb4..7418033 100644
--- a/src/sim/instrDTO.cc
+++ b/src/sim/instrDTO.cc
@@ -19,6 +19,8 @@ signed int InstrDTO::get_s2() { return this->s2; }
 
 signed int InstrDTO::get_s3() { return this->s3; }
 
+Mnemonic InstrDTO::get_mnemonic() { return this->mnemonic; }
+
 void InstrDTO::set_time_of(Accessor a, int i) { this->hist[a] = i; }
 
 void InstrDTO::set_instr_bits(signed int instr) { this->instr_bits = instr; }
@@ -28,3 +30,5 @@ void InstrDTO::set_s1(signed int s) { this->s1 = s; }
 void InstrDTO::set_s2(signed int s) { this->s2 = s; }
 
 void InstrDTO::set_s3(signed int s) { this->s3 = s; }
+
+void InstrDTO::set_mnemonic(Mnemonic m) { this->mnemonic = m; }
diff --git a/src/sim/stage.cc b/src/sim/stage.cc
index 560cc41..8d9dfc0 100644
--- a/src/sim/stage.cc
+++ b/src/sim/stage.cc
@@ -1,12 +1,59 @@
 #include "stage.h"
+#include "utils.h"
+#include <array>
+#include <set>
 
-Stage::Stage(Stage *next) {
-	this->next = next;
-}
+static Logger *global_log = Logger::getInstance();
+
+Stage::Stage(Stage *next) { this->next = next; }
 
 std::array<int, GPR_NUM> Stage::gprs;
 std::array<int, V_NUM> Stage::vrs;
+std::set<unsigned int> Stage::checked_out;
 unsigned int Stage::pc;
 Storage *Stage::storage;
 bool Stage::is_pipelined;
 int Stage::clock_cycle;
+
+Response Stage::check_out(unsigned int &v)
+{
+	Response r;
+	if (this->is_checked_out(v))
+		r = STALLED;
+	else {
+		r = OK;
+		v = this->check_out_register(v);
+	}
+	return r;
+}
+
+bool Stage::is_checked_out(unsigned int r)
+{
+	return this->checked_out.find(r) != this->checked_out.end();
+}
+
+signed int Stage::check_out_register(unsigned int v)
+{
+	signed int r;
+	this->checked_out.insert(v);
+
+	r = this->dereference_register(v);
+	return r;
+}
+
+signed int Stage::dereference_register(unsigned int v)
+{
+	signed int r;
+
+	if (v >= GPR_NUM + V_NUM) {
+		global_log->log(
+			ERROR, string_format(
+					   "instruction tried to access register %d, which does "
+					   "not exist",
+					   v));
+		exit(EXIT_FAILURE);
+	}
+
+	r = (v >= GPR_NUM) ? this->vrs[v % GPR_NUM] : this->gprs[v];
+	return r;
+}