1 files changed, 27 insertions, 0 deletions
diff --git a/rtl/src/arithmetic_unit.v b/rtl/src/arithmetic_unit.v
new file mode 100644
index 0000000..1a2282b
--- /dev/null
+++ b/rtl/src/arithmetic_unit.v
@@ -0,0 +1,27 @@
+module arithmetic_unit (
+  input [31:0] a, 
+  input [31:0] b,
+
+  input [1:0] op,
+  
+  output reg [31:0] result
+);
+
+`include "include/consts.vh"
+
+wire signed [31:0] a_signed, b_signed;
+
+assign a_signed = a;
+assign b_signed = b;
+
+always @ (*) begin
+  case (op)
+    ARITHMETIC_OP_ADD:  result = a + b;                               // ADD
+    ARITHMETIC_OP_SUB:  result = a - b;                               // SUB
+    ARITHMETIC_OP_SLT:  result = { {31{1'b0}}, a_signed < b_signed }; // SLT
+    ARITHMETIC_OP_SLTU: result = { {31{1'b0}}, a < b };               // SLTU
+    default:            result = 32'b0;
+  endcase
+end
+
+endmodule