Files
vortex/rtl/VX_execute_unit.v
2019-11-07 13:27:38 -05:00

132 lines
4.5 KiB
Verilog

`include "VX_define.v"
module VX_execute_unit (
// input wire clk,
// Input
// Request
VX_exec_unit_req_inter VX_exec_unit_req,
// Output
// Writeback
VX_inst_exec_wb_inter VX_inst_exec_wb,
// JAL Response
VX_jal_response_inter VX_jal_rsp,
// Branch Response
VX_branch_response_inter VX_branch_rsp
);
wire[`NT_M1:0][31:0] in_a_reg_data;
wire[`NT_M1:0][31:0] in_b_reg_data;
wire[4:0] in_alu_op;
wire in_rs2_src;
wire[31:0] in_itype_immed;
wire[2:0] in_branch_type;
wire[19:0] in_upper_immed;
wire in_jal;
wire[31:0] in_jal_offset;
wire[31:0] in_curr_PC;
assign in_a_reg_data = VX_exec_unit_req.a_reg_data;
assign in_b_reg_data = VX_exec_unit_req.b_reg_data;
assign in_alu_op = VX_exec_unit_req.alu_op;
assign in_rs2_src = VX_exec_unit_req.rs2_src;
assign in_itype_immed = VX_exec_unit_req.itype_immed;
assign in_branch_type = VX_exec_unit_req.branch_type;
assign in_upper_immed = VX_exec_unit_req.upper_immed;
assign in_jal = VX_exec_unit_req.jal;
assign in_jal_offset = VX_exec_unit_req.jal_offset;
assign in_curr_PC = VX_exec_unit_req.curr_PC;
wire[`NT_M1:0][31:0] alu_result;
genvar index_out_reg;
generate
for (index_out_reg = 0; index_out_reg < `NT; index_out_reg = index_out_reg + 1)
begin
VX_alu vx_alu(
// .in_reg_data (in_reg_data[1:0]),
.in_1 (in_a_reg_data[index_out_reg]),
.in_2 (in_b_reg_data[index_out_reg]),
.in_rs2_src (in_rs2_src),
.in_itype_immed(in_itype_immed),
.in_upper_immed(in_upper_immed),
.in_alu_op (in_alu_op),
.in_curr_PC (in_curr_PC),
.out_alu_result(alu_result[index_out_reg])
);
end
endgenerate
wire [$clog2(`NT)-1:0] jal_branch_use_index;
wire jal_branch_found_valid;
VX_generic_priority_encoder #(.N(`NT)) choose_alu_result(
.valids(VX_exec_unit_req.valid),
.index (jal_branch_use_index),
.found (jal_branch_found_valid)
);
wire[31:0] branch_use_alu_result = alu_result[jal_branch_use_index];
reg temp_branch_dir;
always @(*)
begin
case(VX_exec_unit_req.branch_type)
`BEQ: temp_branch_dir = (branch_use_alu_result == 0) ? `TAKEN : `NOT_TAKEN;
`BNE: temp_branch_dir = (branch_use_alu_result == 0) ? `NOT_TAKEN : `TAKEN;
`BLT: temp_branch_dir = (branch_use_alu_result[31] == 0) ? `NOT_TAKEN : `TAKEN;
`BGT: temp_branch_dir = (branch_use_alu_result[31] == 0) ? `TAKEN : `NOT_TAKEN;
`BLTU: temp_branch_dir = (branch_use_alu_result[31] == 0) ? `NOT_TAKEN : `TAKEN;
`BGTU: temp_branch_dir = (branch_use_alu_result[31] == 0) ? `TAKEN : `NOT_TAKEN;
`NO_BRANCH: temp_branch_dir = `NOT_TAKEN;
default: temp_branch_dir = `NOT_TAKEN;
endcase // in_branch_type
end
wire[`NT_M1:0][31:0] duplicate_PC_data;
genvar i;
generate
for (i = 0; i < `NT; i=i+1)
begin
assign duplicate_PC_data[i] = VX_exec_unit_req.PC_next;
end
endgenerate
// Actual Writeback
assign VX_inst_exec_wb.rd = VX_exec_unit_req.rd;
assign VX_inst_exec_wb.wb = VX_exec_unit_req.wb;
assign VX_inst_exec_wb.wb_valid = VX_exec_unit_req.valid;
assign VX_inst_exec_wb.wb_warp_num = VX_exec_unit_req.warp_num;
assign VX_inst_exec_wb.alu_result = VX_exec_unit_req.jal ? duplicate_PC_data : alu_result;
assign VX_inst_exec_wb.exec_wb_pc = in_curr_PC;
// Jal rsp
assign VX_jal_rsp.jal = in_jal;
assign VX_jal_rsp.jal_dest = $signed(in_a_reg_data[jal_branch_use_index]) + $signed(in_jal_offset);
assign VX_jal_rsp.jal_warp_num = VX_exec_unit_req.warp_num;
// Branch rsp
assign VX_branch_rsp.valid_branch = (VX_exec_unit_req.branch_type != `NO_BRANCH) && (|VX_exec_unit_req.valid);
assign VX_branch_rsp.branch_dir = temp_branch_dir;
assign VX_branch_rsp.branch_warp_num = VX_exec_unit_req.warp_num;
assign VX_branch_rsp.branch_dest = $signed(VX_exec_unit_req.curr_PC) + ($signed(VX_exec_unit_req.itype_immed) << 1); // itype_immed = branch_offset
// always @(*) begin
// case(in_alu_op)
// `CSR_ALU_RW: out_csr_result = in_csr_mask;
// `CSR_ALU_RS: out_csr_result = in_csr_data | in_csr_mask;
// `CSR_ALU_RC: out_csr_result = in_csr_data & (32'hFFFFFFFF - in_csr_mask);
// default: out_csr_result = 32'hdeadbeef;
// endcase
// end
// assign out_is_csr = VX_exec_unit_req.is_csr;
// assign out_csr_address = VX_exec_unit_req.csr_address;
endmodule