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Added 6 more compressed instructions

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Sven Stucki 2015-07-16 01:46:29 +02:00
parent a1430b3394
commit 4289008afe
1 changed files with 25 additions and 6 deletions
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31
compressed_decoder.sv
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@ -69,19 +69,26 @@ module compressed_decoder
3'b011: begin
unique case ({instr_i[12:10], instr_i[6:5]})
5'b00000: begin
// c.xor -> xor rd', rd', rs2'
instr_o = {7'b0, 2'b01, instr_i[4:2], 2'b01, instr_i[9:7], 3'b100, 2'b01, instr_i[9:7], `OPCODE_OP};
end
// c.xor -> xor rd', rd', rs2'
5'b00000: instr_o = {7'b0, 2'b01, instr_i[4:2], 2'b01, instr_i[9:7], 3'b100, 2'b01, instr_i[9:7], `OPCODE_OP};
// c.sltr
// c.sltur -> sltu rd', rs1', rd'
5'b01111: instr_o = {7'b0, 2'b01, instr_i[4:2], 2'b01, instr_i[9:7], 3'b011, 2'b01, instr_i[4:2], `OPCODE_OP};
default: illegal_instr_o = 1'b1;
endcase
end
3'b101: begin
unique case (instr_i[6:5])
// c.add3 -> add rd', rs1', rs2'
2'b00: instr_o = {7'b0, 2'b01, instr_i[4:2], 2'b01, instr_i[9:7], 3'b000, 2'b01, instr_i[12:10], `OPCODE_OP};
// c.sub3
// c.or3 -> or rd'1, rs1', rs2'
2'b10: instr_o = {7'b0, 2'b01, instr_i[4:2], 2'b01, instr_i[9:7], 3'b110, 2'b01, instr_i[12:10], `OPCODE_OP};
// c.and3 -> and rd', rs1', rs2'
2'b11: instr_o = {7'b0, 2'b01, instr_i[4:2], 2'b01, instr_i[9:7], 3'b111, 2'b01, instr_i[12:10], `OPCODE_OP};
default: illegal_instr_o = 1'b1;
endcase
end
@ -102,11 +109,19 @@ module compressed_decoder
unique case (instr_i[15:13])
3'b000: begin
// c.slli -> slli rd, rd, shamt
instr_o = {6'b0, instr_i[12], instr_i[6:2], instr_i[11:7], 3'b001, instr_i[11:7], `OPCODE_OPIMM};
instr_o = {7'b0, instr_i[6:2], instr_i[11:7], 3'b001, instr_i[11:7], `OPCODE_OPIMM};
if (instr_i[11:7] == 5'b0) illegal_instr_o = 1'b1;
if (instr_i[12] == 1'b1 || instr_i[6:2] == 5'b0) illegal_instr_o = 1'b1;
end
3'b001: begin
// c.srli -> srli rd, rd, shamt
instr_o = {7'b0, instr_i[6:2], instr_i[11:7], 3'b101, instr_i[11:7], `OPCODE_OPIMM};
if (instr_i[12] == 1'b1) illegal_instr_o = 1'b1;
if (instr_i[6:2] == 5'b0) illegal_instr_o = 1'b1;
if (instr_i[11:7] == 5'b0) illegal_instr_o = 1'b1;
end
3'b010: begin
// c.swsp -> sw rs2, imm(x2)
instr_o = {4'b0, instr_i[8:7], instr_i[12], instr_i[6:2], 5'h02, 3'b010, instr_i[11:9], 2'b00, `OPCODE_STORE};
@ -114,6 +129,10 @@ module compressed_decoder
3'b100: begin
unique case (instr_i[6:5])
// c.addin -> addi rd', rs1', imm
2'b00: instr_o = {{8 {instr_i[12]}}, instr_i[12:10], 2'b01, instr_i[9:7], 3'b000, 2'b01, instr_i[4:2], `OPCODE_OPIMM};
// c.xorin -> xori rd', rs1', imm
2'b01: instr_o = {{8 {instr_i[12]}}, instr_i[12:10], 2'b01, instr_i[9:7], 3'b100, 2'b01, instr_i[4:2], `OPCODE_OPIMM};
// c.orin -> ori rd', rs1', imm
2'b10: instr_o = {{8 {instr_i[12]}}, instr_i[12:10], 2'b01, instr_i[9:7], 3'b110, 2'b01, instr_i[4:2], `OPCODE_OPIMM};
// c.andin -> andi rd', rs1', imm