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Four more compressed instructions

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Sven Stucki 2015-07-24 18:24:18 +02:00
parent d9b75c2ec0
commit a1b4551804
1 changed files with 17 additions and 3 deletions
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20
compressed_decoder.sv
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@ -79,15 +79,24 @@ module compressed_decoder
unique case ({instr_i[12:10], instr_i[6:5]})
// 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.sll -> sll rd', rd', rs2'
5'b00100: instr_o = {7'b0, 2'b01, instr_i[4:2], 2'b01, instr_i[9:7], 3'b001, 2'b01, instr_i[9:7], `OPCODE_OP};
// c.srl -> srl rd', rd', rs2'
5'b00101: instr_o = {7'b0, 2'b01, instr_i[4:2], 2'b01, instr_i[9:7], 3'b101, 2'b01, instr_i[9:7], `OPCODE_OP};
// c.sltu -> sltu rd', rd', rs2'
5'b00111: instr_o = {7'b0, 2'b01, instr_i[4:2], 2'b01, instr_i[9:7], 3'b011, 2'b01, instr_i[9:7], `OPCODE_OP};
// c.sllr -> sll rd', rs1', rd'
5'b01100: instr_o = {7'b0, 2'b01, instr_i[4:2], 2'b01, instr_i[4:2], 3'b001, 2'b01, instr_i[4:2], `OPCODE_OP};
// c.srlr
// c.sltr
// c.srlr -> srl rd', rs1', rd'
5'b01101: instr_o = {7'b0, 2'b01, instr_i[4:2], 2'b01, instr_i[4:2], 3'b101, 2'b01, instr_i[4:2], `OPCODE_OP};
// 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};
// c.sra
// c.slt
// c.sltr
default: illegal_instr_o = 1'b1;
endcase
end
@ -148,6 +157,11 @@ module compressed_decoder
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};
end
3'b011: begin
// c.bltz -> blt rs1', x0, imm
instr_o = {{3 {instr_i[12]}}, instr_i[12:10], instr_i[2], 5'b0, 2'b01, instr_i[9:7], 3'b100, instr_i[6:3], instr_i[12], `OPCODE_BRANCH};
end
3'b100: begin
unique case (instr_i[6:5])
// c.addin -> addi rd', rs1', imm