diff options
Diffstat (limited to 'rv64cpu/rtl/core/alu.sv')
| -rw-r--r-- | rv64cpu/rtl/core/alu.sv | 32 |
1 files changed, 16 insertions, 16 deletions
diff --git a/rv64cpu/rtl/core/alu.sv b/rv64cpu/rtl/core/alu.sv index ac2e9c9..abfc238 100644 --- a/rv64cpu/rtl/core/alu.sv +++ b/rv64cpu/rtl/core/alu.sv @@ -21,44 +21,44 @@ module alu import rv64_pkg::*; ( input alu_op_t alu_op, // ALU operation select (from decoder) - input logic [XLEN-1:0] rs1_val, // Operand 1 (register rs1 value or PC) - input logic [XLEN-1:0] rs2_val, // Operand 2 (register rs2 value or immediate) + input logic [XLEN-1:0] operand_a, // Operand 1 (register rs1 value or PC) + input logic [XLEN-1:0] operand_b, // Operand 2 (register rs2 value or immediate) - output logic [XLEN-1:0] alu_res // ALU result + output logic [XLEN-1:0] alu_result // ALU result ); // Shift amount: RV64I uses lower 6 bits of rs2 (shamt[5:0]) logic [5:0] shamt; - assign shamt = rs2_val[5:0]; + assign shamt = operand_b[5:0]; always_comb begin - alu_res = '0; + alu_result = '0; case (alu_op) - ALU_ADD: alu_res = rs1_val + rs2_val; - ALU_SUB: alu_res = rs1_val - rs2_val; + ALU_ADD: alu_result = operand_a + operand_b; + ALU_SUB: alu_result = operand_a - operand_b; // Logical left shift: the shift amount is the lower 6 bits of rs2 - ALU_SLL: alu_res = rs1_val << shamt; + ALU_SLL: alu_result = operand_a << shamt; // Set less than (signed) - ALU_SLT: alu_res = {63'b0, $signed(rs1_val) < $signed(rs2_val)}; + ALU_SLT: alu_result = {63'b0, $signed(operand_a) < $signed(operand_b)}; // Set less than (unsigned) - ALU_SLTU: alu_res = {63'b0, rs1_val < rs2_val}; + ALU_SLTU: alu_result = {63'b0, operand_a < operand_b}; - ALU_XOR: alu_res = rs1_val ^ rs2_val; + ALU_XOR: alu_result = operand_a ^ operand_b; // Logical right shift: the shift amount is the lower 6 bits of rs2 - ALU_SRL: alu_res = rs1_val >> shamt; + ALU_SRL: alu_result = operand_a >> shamt; // Arithmetic right shift: the shift amount is the lower 6 bits of rs2 - ALU_SRA: alu_res = $unsigned($signed(rs1_val) >>> shamt); + ALU_SRA: alu_result = $unsigned($signed(operand_a) >>> shamt); - ALU_OR: alu_res = rs1_val | rs2_val; - ALU_AND: alu_res = rs1_val & rs2_val; + ALU_OR: alu_result = operand_a | operand_b; + ALU_AND: alu_result = operand_a & operand_b; - default: alu_res = '0; + default: alu_result = '0; endcase end |