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-rw-r--r--src/instruction_decode.v56
1 files changed, 0 insertions, 56 deletions
diff --git a/src/instruction_decode.v b/src/instruction_decode.v
deleted file mode 100644
index 2a7eba7..0000000
--- a/src/instruction_decode.v
+++ /dev/null
@@ -1,56 +0,0 @@
-module instruction_decode(
- input [31:0] instruction,
- output [6:0] opcode,
- output [2:0] funct3,
- output [6:0] funct7,
- output reg [31:0] immediate,
- output [4:0] rs1, rs2, rd
-);
-
-parameter INSTRUCTION_FORMAT_UNKNOWN = 3'b000,
- INSTRUCTION_FORMAT_R = 3'b001,
- INSTRUCTION_FORMAT_I = 3'b010,
- INSTRUCTION_FORMAT_S = 3'b011,
- INSTRUCTION_FORMAT_B = 3'b100,
- INSTRUCTION_FORMAT_U = 3'b101,
- INSTRUCTION_FORMAT_J = 3'b110;
-
-reg [2:0] instruction_format;
-
-always @ (*) begin
- case (opcode)
- 7'b0110011: instruction_format <= INSTRUCTION_FORMAT_R; // ADD, SUB, SLL, SLT, SLTU, XOR, SRL, SRA, OR, AND
- 7'b0010011: instruction_format <= INSTRUCTION_FORMAT_I; // ADDI, SLTI, SLTIU, XORI, ORI, ANDI, SLLI, SRLI, SRAI
- 7'b0000011: instruction_format <= INSTRUCTION_FORMAT_I; // LB, LH, LW, LBU, LHU
- 7'b1100111: instruction_format <= INSTRUCTION_FORMAT_I; // JALR
- 7'b0100011: instruction_format <= INSTRUCTION_FORMAT_S; // SB, SH, SW
- 7'b1100011: instruction_format <= INSTRUCTION_FORMAT_B; // BEQ, BNE, BLT, BGE, BLTU, BGEU
- 7'b0110111: instruction_format <= INSTRUCTION_FORMAT_U; // LUI
- 7'b0010111: instruction_format <= INSTRUCTION_FORMAT_U; // AUIPC
- 7'b1101111: instruction_format <= INSTRUCTION_FORMAT_J; // JAL
- 7'b0001111: instruction_format <= INSTRUCTION_FORMAT_I; // FENCE, FENCE.I
- 7'b1110011: instruction_format <= INSTRUCTION_FORMAT_I; // ECALL, EBREAK, CSRRW, CSRRS, CSRRC, CSRRWI, CSRRSI, CSRRCI
- default: instruction_format <= INSTRUCTION_FORMAT_UNKNOWN;
- endcase
-end
-
-always @ (*) begin
- case (instruction_format)
- INSTRUCTION_FORMAT_I: immediate <= { {21{instruction[31]}}, instruction[30:20] };
- INSTRUCTION_FORMAT_S: immediate <= { {21{instruction[31]}}, instruction[30:25], instruction[11:8], instruction[7] };
- INSTRUCTION_FORMAT_B: immediate <= { {20{instruction[31]}}, instruction[7], instruction[30:25], instruction[11:8], 1'b0 };
- INSTRUCTION_FORMAT_U: immediate <= { instruction[31], instruction[30:12], 12'b0 };
- INSTRUCTION_FORMAT_J: immediate <= { {12{instruction[31]}}, instruction[19:12], instruction[20], instruction[30:21], 1'b0 };
- default: immediate <= 32'b0;
- endcase
-end
-
-assign opcode = instruction[6:0];
-assign funct3 = instruction[14:12];
-assign funct7 = instruction[31:25];
-assign rs1 = instruction[19:15];
-assign rs2 = instruction[24:20];
-assign rd = instruction[11:7];
-
-
-endmodule