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Combine lt and eq regs to cmp_r in serv_alu

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Olof Kindgren
2021-02-01 22:37:45 +01:00
parent 308612fd9e
commit f70b79fd8f
2 changed files with 7 additions and 11 deletions
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18
rtl/serv_alu.v
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@@ -25,10 +25,8 @@ module serv_alu
output wire o_rd); output wire o_rd);
wire result_add; wire result_add;
wire result_eq;
reg result_lt_r; reg cmp_r;
reg eq_r;
reg [5:0] shamt_r; reg [5:0] shamt_r;
@@ -41,13 +39,13 @@ module serv_alu
wire rs1_sx = i_rs1 & i_cmp_sig; wire rs1_sx = i_rs1 & i_cmp_sig;
wire op_b_sx = op_b & i_cmp_sig; wire op_b_sx = op_b & i_cmp_sig;
wire result_lt = rs1_sx + ~op_b_sx + add_cy;
wire add_b = op_b^i_sub; wire add_b = op_b^i_sub;
assign {add_cy,result_add} = i_rs1+add_b+add_cy_r; assign {add_cy,result_add} = i_rs1+add_b+add_cy_r;
assign result_eq = !result_add & eq_r; wire result_lt = rs1_sx + ~op_b_sx + add_cy;
wire result_eq = !result_add & (cmp_r | i_cnt0);
assign o_cmp = i_cmp_eq ? result_eq : result_lt; assign o_cmp = i_cmp_eq ? result_eq : result_lt;
@@ -56,7 +54,7 @@ module serv_alu
assign o_rd = (i_rd_sel[0] & result_add) | assign o_rd = (i_rd_sel[0] & result_add) |
(i_rd_sel[1] & i_buf) | (i_rd_sel[1] & i_buf) |
(i_rd_sel[2] & result_lt_r & i_cnt0) | (i_rd_sel[2] & cmp_r & i_cnt0) |
(i_rd_sel[3] & result_bool); (i_rd_sel[3] & result_bool);
@@ -67,10 +65,8 @@ module serv_alu
always @(posedge clk) begin always @(posedge clk) begin
add_cy_r <= i_en ? add_cy : i_sub; add_cy_r <= i_en ? add_cy : i_sub;
if (i_en) begin if (i_en)
result_lt_r <= result_lt; cmp_r <= o_cmp;
end
eq_r <= result_eq | ~i_en;
if (i_shamt_en) if (i_shamt_en)
shamt_r <= shamt; shamt_r <= shamt;