diff --git a/.gitignore b/.gitignore
index 378eac2..cc65b37 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1 @@
-build
+*.~lock*
\ No newline at end of file
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index e7a3024..6ef47ac 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,13 +1,16 @@
 image: ubuntu
 
 stages:
+  - install
   - build
 
-build-job:
-  stage: build
+install-job:
+  stage: install
   script:
     - echo "Installing dependencies..."
     - apt update && apt install -y make iverilog gcc-8-riscv64-linux-gnu
-    - echo "Compiling the code..."
-    - make sim
-    - echo "Compile complete."
+
+testbench:
+  stage: build
+  script:
+    - make -C testbench
diff --git a/Makefile b/Makefile
deleted file mode 100644
index 8f2f6d5..0000000
--- a/Makefile
+++ /dev/null
@@ -1,63 +0,0 @@
-BUILD_DIR = build
-
-# ================
-# Hardware options
-# ================
-# SOURCE_V = $(wildcard hdl/*.v)
-# TESTBENCH_V = $(wildcard hdl/tb/*.v)
-SOURCE_V = hdl/core.v
-TESTBENCH_V = hdl/tb/core_tb.v
-
-# ================
-# Software options
-# ================
-# SOURCE_C = $(wildcard test/*.c)
-SOURCE_C = 
-SOURCE_AS = $(wildcard test/*.S)
-OBJ = $(addprefix $(BUILD_DIR)/, $(notdir $(SOURCE_AS:.S=.o)))
-OBJ += $(addprefix $(BUILD_DIR)/, $(notdir $(SOURCE_C:.c=.o)))
-
-CC = riscv64-linux-gnu-gcc-8
-# CFLAGS = -march=rv32i -mabi=ilp32
-CFLAGS = -march=rv64i -mabi=lp64
-
-AS = riscv64-linux-gnu-as
-ASFLAGS = $(CFLAGS)
-
-LD = riscv64-linux-gnu-ld
-LDFLAGS = -T
-
-all: sim
-
-## Hardware
-$(BUILD_DIR)/tb.out: $(SOURCE_V) $(TESTBENCH_V) | $(BUILD_DIR)
-	iverilog $^ -o $@
-
-## Software
-$(BUILD_DIR)/%.o: test/%.S | $(BUILD_DIR)
-	$(AS) $(ASFLAGS) $^ -o $@
-
-$(BUILD_DIR)/%.o: test/%.c | $(BUILD_DIR)
-	$(CC) $(CFLAGS) $^ -o $@
-
-$(BUILD_DIR)/%.elf: test/%.ld $(OBJ) | $(BUILD_DIR)
-	$(LD) $(LDFLAGS) $^ -o $@
-
-%.hex: %.elf
-	riscv64-linux-gnu-objcopy --target=verilog $< $@
-
-$(BUILD_DIR)/core_tb.vcd: $(BUILD_DIR)/tb.out $(BUILD_DIR)/test.hex
-	cd $(BUILD_DIR) && ./tb.out | tee sim_log.txt
-
-sim: $(BUILD_DIR)/core_tb.vcd
-	@grep -q "SUCCESS" $(BUILD_DIR)/sim_log.txt
-
-## General
-$(BUILD_DIR):
-	mkdir -p $(BUILD_DIR)
-
-clean:
-	rm -rf $(BUILD_DIR)
-
-.SECONDARY:
-.PHONY: all clean sim
diff --git a/test/decoder.xlsx b/decoder.xlsx
similarity index 100%
rename from test/decoder.xlsx
rename to decoder.xlsx
diff --git a/hdl/.gitignore b/hdl/.gitignore
deleted file mode 100644
index bc9a8c8..0000000
--- a/hdl/.gitignore
+++ /dev/null
@@ -1,2 +0,0 @@
-*.out
-*.vcd
\ No newline at end of file
diff --git a/hdl/tb/core_tb.gtkw b/hdl/tb/core_tb.gtkw
deleted file mode 100644
index f9c11d4..0000000
--- a/hdl/tb/core_tb.gtkw
+++ /dev/null
@@ -1,203 +0,0 @@
-[*]
-[*] GTKWave Analyzer v3.3.103 (w)1999-2019 BSI
-[*] Sun Jul  4 02:57:58 2021
-[*]
-[dumpfile] "/home/brendan/Documents/Projects/0039_cpu/build/core_tb.vcd"
-[dumpfile_mtime] "Sun Jul  4 02:57:52 2021"
-[dumpfile_size] 500611
-[savefile] "/home/brendan/Documents/Projects/0039_cpu/hdl/tb/core_tb.gtkw"
-[timestart] 0
-[size] 1920 1016
-[pos] -1 -1
-*-19.000000 3297000 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1
-[treeopen] core_tb.
-[treeopen] core_tb.dut.
-[sst_width] 289
-[signals_width] 277
-[sst_expanded] 1
-[sst_vpaned_height] 301
-@200
--TB
-@28
-core_tb.clk
-core_tb.reset
-@200
--
-@22
-core_tb.mem_data_addr[31:0]
-core_tb.mem_data_rdata[31:0]
-@28
-core_tb.mem_data_rvalid
-@22
-core_tb.mem_data_wdata[31:0]
-@28
-core_tb.mem_data_we
-core_tb.mem_data_wready
-@22
-core_tb.mem_inst_addr[31:0]
-core_tb.mem_inst_data[31:0]
-@23
-core_tb.\mem[2048][7:0]
-@200
--
--DUT
-@22
-core_tb.dut.\regfile[0][31:0]
-core_tb.dut.\regfile[1][31:0]
-core_tb.dut.\regfile[2][31:0]
-core_tb.dut.\regfile[3][31:0]
-core_tb.dut.\regfile[4][31:0]
-core_tb.dut.\regfile[5][31:0]
-core_tb.dut.\regfile[6][31:0]
-core_tb.dut.\regfile[7][31:0]
-core_tb.dut.\regfile[8][31:0]
-core_tb.dut.\regfile[9][31:0]
-core_tb.dut.\regfile[10][31:0]
-core_tb.dut.\regfile[11][31:0]
-core_tb.dut.\regfile[12][31:0]
-core_tb.dut.\regfile[13][31:0]
-core_tb.dut.\regfile[14][31:0]
-core_tb.dut.\regfile[15][31:0]
-core_tb.dut.\regfile[16][31:0]
-core_tb.dut.\regfile[17][31:0]
-core_tb.dut.\regfile[18][31:0]
-core_tb.dut.\regfile[19][31:0]
-core_tb.dut.\regfile[20][31:0]
-core_tb.dut.\regfile[21][31:0]
-core_tb.dut.\regfile[22][31:0]
-core_tb.dut.\regfile[23][31:0]
-@c00022
-core_tb.dut.\regfile[24][31:0]
-@28
-(0)core_tb.dut.\regfile[24][31:0]
-(1)core_tb.dut.\regfile[24][31:0]
-(2)core_tb.dut.\regfile[24][31:0]
-(3)core_tb.dut.\regfile[24][31:0]
-(4)core_tb.dut.\regfile[24][31:0]
-(5)core_tb.dut.\regfile[24][31:0]
-(6)core_tb.dut.\regfile[24][31:0]
-(7)core_tb.dut.\regfile[24][31:0]
-(8)core_tb.dut.\regfile[24][31:0]
-(9)core_tb.dut.\regfile[24][31:0]
-(10)core_tb.dut.\regfile[24][31:0]
-(11)core_tb.dut.\regfile[24][31:0]
-(12)core_tb.dut.\regfile[24][31:0]
-(13)core_tb.dut.\regfile[24][31:0]
-(14)core_tb.dut.\regfile[24][31:0]
-(15)core_tb.dut.\regfile[24][31:0]
-(16)core_tb.dut.\regfile[24][31:0]
-(17)core_tb.dut.\regfile[24][31:0]
-(18)core_tb.dut.\regfile[24][31:0]
-(19)core_tb.dut.\regfile[24][31:0]
-(20)core_tb.dut.\regfile[24][31:0]
-(21)core_tb.dut.\regfile[24][31:0]
-(22)core_tb.dut.\regfile[24][31:0]
-(23)core_tb.dut.\regfile[24][31:0]
-(24)core_tb.dut.\regfile[24][31:0]
-(25)core_tb.dut.\regfile[24][31:0]
-(26)core_tb.dut.\regfile[24][31:0]
-(27)core_tb.dut.\regfile[24][31:0]
-(28)core_tb.dut.\regfile[24][31:0]
-(29)core_tb.dut.\regfile[24][31:0]
-(30)core_tb.dut.\regfile[24][31:0]
-(31)core_tb.dut.\regfile[24][31:0]
-@1401200
--group_end
-@22
-core_tb.dut.\regfile[25][31:0]
-core_tb.dut.\regfile[26][31:0]
-core_tb.dut.\regfile[27][31:0]
-core_tb.dut.\regfile[28][31:0]
-core_tb.dut.\regfile[29][31:0]
-core_tb.dut.\regfile[30][31:0]
-core_tb.dut.\regfile[31][31:0]
-@200
--
-@c00022
-core_tb.dut.r_if_pc[31:0]
-@28
-(0)core_tb.dut.r_if_pc[31:0]
-(1)core_tb.dut.r_if_pc[31:0]
-(2)core_tb.dut.r_if_pc[31:0]
-(3)core_tb.dut.r_if_pc[31:0]
-(4)core_tb.dut.r_if_pc[31:0]
-(5)core_tb.dut.r_if_pc[31:0]
-(6)core_tb.dut.r_if_pc[31:0]
-(7)core_tb.dut.r_if_pc[31:0]
-(8)core_tb.dut.r_if_pc[31:0]
-(9)core_tb.dut.r_if_pc[31:0]
-(10)core_tb.dut.r_if_pc[31:0]
-(11)core_tb.dut.r_if_pc[31:0]
-(12)core_tb.dut.r_if_pc[31:0]
-(13)core_tb.dut.r_if_pc[31:0]
-(14)core_tb.dut.r_if_pc[31:0]
-(15)core_tb.dut.r_if_pc[31:0]
-(16)core_tb.dut.r_if_pc[31:0]
-(17)core_tb.dut.r_if_pc[31:0]
-(18)core_tb.dut.r_if_pc[31:0]
-(19)core_tb.dut.r_if_pc[31:0]
-(20)core_tb.dut.r_if_pc[31:0]
-(21)core_tb.dut.r_if_pc[31:0]
-(22)core_tb.dut.r_if_pc[31:0]
-(23)core_tb.dut.r_if_pc[31:0]
-(24)core_tb.dut.r_if_pc[31:0]
-(25)core_tb.dut.r_if_pc[31:0]
-(26)core_tb.dut.r_if_pc[31:0]
-(27)core_tb.dut.r_if_pc[31:0]
-(28)core_tb.dut.r_if_pc[31:0]
-(29)core_tb.dut.r_if_pc[31:0]
-(30)core_tb.dut.r_if_pc[31:0]
-(31)core_tb.dut.r_if_pc[31:0]
-@1401200
--group_end
-@200
--
-@28
-core_tb.dut.r_id_valid
-@22
-core_tb.dut.r_id_pc[31:0]
-core_tb.dut.r_id_inst[31:0]
-core_tb.dut.s_id_immed_btype[31:0]
-core_tb.dut.s_id_immed_itype[31:0]
-core_tb.dut.s_id_immed_jtype[31:0]
-core_tb.dut.s_id_immed_stype[31:0]
-core_tb.dut.s_id_immed_utype[31:0]
-@200
--
-@28
-core_tb.dut.r_ex_valid
-@22
-core_tb.dut.r_ex_pc[31:0]
-core_tb.dut.r_ex_inst[31:0]
-@24
-core_tb.dut.r_ex_rs1[4:0]
-core_tb.dut.r_ex_rs2[4:0]
-core_tb.dut.r_ex_rd[4:0]
-@22
-core_tb.dut.r_ex_s1[31:0]
-core_tb.dut.r_ex_s2[31:0]
-core_tb.dut.r_ex_aluop[3:0]
-@28
-core_tb.dut.r_ex_jump
-core_tb.dut.r_ex_branch
-core_tb.dut.r_ex_branch_pol
-core_tb.dut.r_ex_load
-core_tb.dut.r_ex_store
-@200
--
-@22
-core_tb.dut.r_mem_pc[31:0]
-core_tb.dut.r_mem_alu_out[31:0]
-@28
-core_tb.dut.r_mem_load
-core_tb.dut.r_mem_store
-@200
--
-@22
-core_tb.dut.r_wb_pc[31:0]
-core_tb.dut.r_wb_alu_out[31:0]
-core_tb.dut.r_wb_load_data[31:0]
-@28
-core_tb.dut.r_wb_load
-[pattern_trace] 1
-[pattern_trace] 0
diff --git a/hdl/other_projects/axi_lite.md b/other_projects/axi_lite.md
similarity index 100%
rename from hdl/other_projects/axi_lite.md
rename to other_projects/axi_lite.md
diff --git a/hdl/other_projects/axi_lite_if.sv b/other_projects/axi_lite_if.sv
similarity index 100%
rename from hdl/other_projects/axi_lite_if.sv
rename to other_projects/axi_lite_if.sv
diff --git a/hdl/other_projects/axi_lite_memory.v b/other_projects/axi_lite_memory.v
similarity index 100%
rename from hdl/other_projects/axi_lite_memory.v
rename to other_projects/axi_lite_memory.v
diff --git a/hdl/other_projects/correlator.v b/other_projects/correlator.v
similarity index 100%
rename from hdl/other_projects/correlator.v
rename to other_projects/correlator.v
diff --git a/hdl/other_projects/gps.v b/other_projects/gps.v
similarity index 100%
rename from hdl/other_projects/gps.v
rename to other_projects/gps.v
diff --git a/hdl/other_projects/test.sv b/other_projects/test.sv
similarity index 100%
rename from hdl/other_projects/test.sv
rename to other_projects/test.sv
diff --git a/hdl/other_projects/test_sv.sv b/other_projects/test_sv.sv
similarity index 100%
rename from hdl/other_projects/test_sv.sv
rename to other_projects/test_sv.sv
diff --git a/hdl/other_projects/top.v b/other_projects/top.v
similarity index 100%
rename from hdl/other_projects/top.v
rename to other_projects/top.v
diff --git a/hdl/core.v b/src/bh_cpu.v
similarity index 100%
rename from hdl/core.v
rename to src/bh_cpu.v
diff --git a/test/.gitignore b/test/.gitignore
deleted file mode 100644
index cc65b37..0000000
--- a/test/.gitignore
+++ /dev/null
@@ -1 +0,0 @@
-*.~lock*
\ No newline at end of file
diff --git a/testbench/.gitignore b/testbench/.gitignore
new file mode 100644
index 0000000..e31d0ad
--- /dev/null
+++ b/testbench/.gitignore
@@ -0,0 +1,3 @@
+*.out
+*.vcd
+*.log
\ No newline at end of file
diff --git a/testbench/Makefile b/testbench/Makefile
new file mode 100644
index 0000000..08c3f35
--- /dev/null
+++ b/testbench/Makefile
@@ -0,0 +1,19 @@
+all: verify
+
+# BENCHES = $(filter-out common/, $(sort $(dir $(wildcard */))))
+BENCHES = basic_test
+
+$(info $$BENCHES is [${BENCHES}])
+
+verify:
+	@for d in $(BENCHES); do \
+		make -C $d verify; \
+	done
+
+clean:
+	@for d in $(BENCHES); do \
+		make -C $d clean; \
+	done
+
+.SECONDARY:
+.PHONY: all clean verify
diff --git a/testbench/basic_test/Makefile b/testbench/basic_test/Makefile
new file mode 100644
index 0000000..b9ea799
--- /dev/null
+++ b/testbench/basic_test/Makefile
@@ -0,0 +1,64 @@
+all: verify
+
+TESTBENCH_V = $(wildcard *tb.sv)
+SOURCE_V = $(wildcard ../../src/*.v ../../src/*.sv)
+SOURCE_V += $(wildcard ../common/*.v) $(wildcard ../common/*.sv)
+LOGS = $(TESTBENCH_V:.sv=.log)
+
+# SOURCE_C = $(wildcard *.c)
+SOURCE_C = 
+SOURCE_AS = $(wildcard *.S)
+OBJ = $(notdir $(SOURCE_AS:.S=.o))
+OBJ += $(notdir $(SOURCE_C:.c=.o))
+
+CC = riscv64-linux-gnu-gcc-8
+# CFLAGS = -march=rv32i -mabi=ilp32
+CFLAGS = -march=rv64i -mabi=lp64
+
+CPPFLAGS =
+
+AS = riscv64-linux-gnu-as
+ASFLAGS = $(CFLAGS)
+
+LD = riscv64-linux-gnu-ld
+LDFLAGS = -T
+
+
+# $(info $$TESTBENCH_V is [${TESTBENCH_V}])
+# $(info $$SOURCE_V is [${SOURCE_V}])
+# $(info $$LOGS is [${LOGS}])
+# $(info $$SOURCE_C is [${SOURCE_C}])
+# $(info $$SOURCE_AS is [${SOURCE_AS}])
+# $(info $$OBJ is [${OBJ}])
+
+
+%.o: %.S
+	$(AS) $(ASFLAGS) $^ -o $@
+
+%.o: %.c
+	$(CC) $(CPPFLAGS) $(CFLAGS) $^ -o $@
+
+%.elf: %.ld $(OBJ)
+	$(LD) $(LDFLAGS) $^ -o $@
+
+%.hex: %.elf
+	riscv64-linux-gnu-objcopy --target=verilog $< $@
+
+%.out: %.sv $(SOURCE_V)
+	iverilog -o $@ $^
+
+%.vcd %.log: %.out %.hex
+	./$< | tee $(patsubst %.out, %.log, $<)
+
+verify: $(LOGS)
+	@echo "Checking log for \"ERROR:\"..."
+	@! grep "ERROR:" $^
+	@echo "Checking log for \"SUCCESS:\"..."
+	@grep "SUCCESS:" $^
+
+clean:
+	rm -rf *.vcd *.log *.out *.hex
+
+.SECONDARY: %.log %.vcd
+.PHONY: all clean verify
+
diff --git a/test/main.c b/testbench/basic_test/main.c
similarity index 100%
rename from test/main.c
rename to testbench/basic_test/main.c
diff --git a/test/test.ld b/testbench/basic_test/tb.ld
similarity index 100%
rename from test/test.ld
rename to testbench/basic_test/tb.ld
diff --git a/hdl/tb/core_tb.v b/testbench/basic_test/tb.sv
similarity index 90%
rename from hdl/tb/core_tb.v
rename to testbench/basic_test/tb.sv
index 8831b91..89f9b3f 100644
--- a/hdl/tb/core_tb.v
+++ b/testbench/basic_test/tb.sv
@@ -1,14 +1,15 @@
 `timescale 1ns/1ps
 
-module core_tb();
+module tb();
 
 localparam ADDR_FAILCODE = 32'h800;
+localparam WATCHDOG_MAX = 32'h00001000;
 
 initial $timeformat(-9, 2, " ns", 20);
 initial begin: dump
     integer i;
-    $dumpfile("core_tb.vcd");
-    $dumpvars(0, core_tb);
+    $dumpfile("tb.vcd");
+    $dumpvars(0, tb);
     for (i=0; i<32; i=i+1) begin
         $dumpvars(0, dut.regfile[i]);
     end
@@ -25,7 +26,7 @@ localparam  DATA_INVALID    = 32'hdeadbeef;
 
 // Memory
 reg [7:0] mem [0:MEM_LENGTH-1];
-initial $readmemh("test.hex", mem);
+initial $readmemh("tb.hex", mem);
 
 // Instruction Memory
 wire [31:0] mem_inst_addr;
@@ -113,23 +114,34 @@ initial begin
     $finish;
 end
 
+integer watchdog = 0;
+logic [31:0] returnval;
 always @(posedge clk) begin
     #100
-    case ({mem[ADDR_FAILCODE+3], mem[ADDR_FAILCODE+2], mem[ADDR_FAILCODE+1], mem[ADDR_FAILCODE+0]})
+    returnval = {mem[ADDR_FAILCODE+3], mem[ADDR_FAILCODE+2], mem[ADDR_FAILCODE+1], mem[ADDR_FAILCODE+0]};
+    case (returnval)
         32'h00000000: begin
             // Initial value
         end
         32'hffffffff: begin
             // Success
+            #100
             $display("%0t:\tSUCCESS: TEST PASSED", $time);
             $finish;
         end
         default: begin
-            $display("%0t:\tERROR: FAILCODE = 0x%h", $time, {mem[ADDR_FAILCODE+3], mem[ADDR_FAILCODE+2], mem[ADDR_FAILCODE+1], mem[ADDR_FAILCODE+0]});
+            $display("%0t:\tERROR: FAILCODE = 0x%h", $time, returnval);
             #200
             $finish;
         end
     endcase
+
+    watchdog = watchdog + 1;
+    if (watchdog > WATCHDOG_MAX) begin
+            $display("%0t:\tERROR: WATCHDOG", $time);
+            #200
+            $finish;
+    end
 end
 
 always #2 clk  = !clk;
diff --git a/test/test.S b/testbench/basic_test/test.S
similarity index 99%
rename from test/test.S
rename to testbench/basic_test/test.S
index c8e40bc..130a4b3 100644
--- a/test/test.S
+++ b/testbench/basic_test/test.S
@@ -316,6 +316,7 @@ done:
     addi    x30, x30, 0xff      # x31 = 0x00ffffff
     slli    x30, x30, 8         # x31 = 0xffffff00
     addi    x30, x30, 0xff      # x31 = 0xffffffff
+    # slli    x30, x30, 1         # x31 = 0xfffffffe // this should cause a fail
     nop
     nop
     nop
@@ -338,6 +339,7 @@ done:
     addi    x5, x0, 1           # x5 = 1
     addi    x6, x0, 1           # x6 = 1
 
+loop_init:
     # counter and infinite loop
     addi    x31, x0, 1          # x1 = 1
 
diff --git a/testbench/common/axi4_lite.sv b/testbench/common/axi4_lite.sv
new file mode 100644
index 0000000..750442e
--- /dev/null
+++ b/testbench/common/axi4_lite.sv
@@ -0,0 +1,5 @@
+module axi4_lite(
+    input wire aclk
+);
+
+endmodule
\ No newline at end of file
diff --git a/testbench/testbench_tb.gtkw b/testbench/testbench_tb.gtkw
new file mode 100644
index 0000000..f7ab7a5
--- /dev/null
+++ b/testbench/testbench_tb.gtkw
@@ -0,0 +1,38 @@
+[*]
+[*] GTKWave Analyzer v3.3.86 (w)1999-2017 BSI
+[*] Wed Aug 11 06:10:48 2021
+[*]
+[dumpfile] "/home/brendan/Documents/Projects/0039_cpu/testbench/basic_test/tb.vcd"
+[dumpfile_mtime] "Wed Aug 11 06:09:59 2021"
+[dumpfile_size] 511500
+[savefile] "/home/brendan/Documents/Projects/0039_cpu/testbench/testbench_tb.gtkw"
+[timestart] 0
+[size] 1920 1052
+[pos] -1970 -28
+*-20.000000 3402000 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1
+[treeopen] tb.
+[sst_width] 289
+[signals_width] 277
+[sst_expanded] 1
+[sst_vpaned_height] 352
+@28
+tb.clk
+tb.reset
+@22
+tb.mem_inst_addr[31:0]
+tb.mem_inst_data[31:0]
+tb.mem_data_addr[31:0]
+tb.mem_data_rdata[31:0]
+@28
+tb.mem_data_rvalid
+@22
+tb.mem_data_wdata[31:0]
+tb.mem_data_wmask[3:0]
+@28
+tb.mem_data_we
+tb.mem_data_wready
+@22
+tb.returnval[31:0]
+tb.dut.\regfile[31][31:0]
+[pattern_trace] 1
+[pattern_trace] 0