1 files changed, 21 insertions, 0 deletions
diff --git a/rtl/src/alu_b_src_mux.v b/rtl/src/alu_b_src_mux.v
new file mode 100644
index 0000000..5932f9e
--- /dev/null
+++ b/rtl/src/alu_b_src_mux.v
@@ -0,0 +1,21 @@
+module alu_b_src_mux (
+  input [31:0] src_rd2_buf,
+  input [31:0] src_imm,
+
+  input [1:0] alu_b_src,
+  
+  output reg [31:0] alu_b
+);
+
+`include "include/consts.vh"
+
+always @(*) begin
+  case (alu_b_src)
+    ALU_B_SRC_RD2_BUF: alu_b = src_rd2_buf;
+    ALU_B_SRC_IMM:     alu_b = src_imm;
+    ALU_B_SRC_4:       alu_b = 32'h4;
+    default:           alu_b = 32'b0;
+  endcase
+end
+
+endmodule