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Cleanup of some width mismatches in instruction decompress

This commit is contained in:
Luke Wren 2022-08-20 14:58:41 +01:00
parent 276830ecb6
commit dbe9a7824a
1 changed files with 57 additions and 32 deletions
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89
hdl/hazard3_instr_decompress.v
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@ -27,17 +27,42 @@ wire [W_REGADDR-1:0] rd_s = {2'b01, instr_in[4:2]};
wire [W_REGADDR-1:0] rs1_s = {2'b01, instr_in[9:7]}; wire [W_REGADDR-1:0] rs1_s = {2'b01, instr_in[9:7]};
wire [W_REGADDR-1:0] rs2_s = {2'b01, instr_in[4:2]}; wire [W_REGADDR-1:0] rs2_s = {2'b01, instr_in[4:2]};
// Mapping of cx -> x immediate formats (we are *expanding* instructions, not
// decoding them):
// I don't even O_O wire [31:0] imm_ci = {
{7{instr_in[12]}},
instr_in[6:2],
20'h00000
};
wire [31:0] imm_ci = {{7{instr_in[12]}}, instr_in[6:2], {20{1'b0}}}; wire [31:0] imm_cj = {
instr_in[12],
instr_in[8],
instr_in[10:9],
instr_in[6],
instr_in[7],
instr_in[2],
instr_in[11],
instr_in[5:3],
{9{instr_in[12]}},
12'h000
};
wire [31:0] imm_cj = {instr_in[12], instr_in[8], instr_in[10:9], instr_in[6], instr_in[7], wire [31:0] imm_cb ={
instr_in[2], instr_in[11], instr_in[5:3], {9{instr_in[12]}}, {12{1'b0}}}; {4{instr_in[12]}},
instr_in[6:5],
instr_in[2],
13'h0000,
instr_in[11:10],
instr_in[4:3],
instr_in[12],
7'h00
};
wire [31:0] imm_cb = function [31:0] rfmt_rd; input [4:0] rd; begin rfmt_rd = {20'h00000, rd, 7'h00}; end endfunction
{{20{1'b0}}, instr_in[11:10], instr_in[4:3], instr_in[12], {7{1'b0}}} | function [31:0] rfmt_rs1; input [4:0] rs1; begin rfmt_rs1 = {12'h000, rs1, 15'h0000}; end endfunction
{{4{instr_in[12]}}, instr_in[6:5], instr_in[2], {25{1'b0}}}; function [31:0] rfmt_rs2; input [4:0] rs2; begin rfmt_rs2 = {7'h00, rs2, 20'h00000}; end endfunction
generate generate
if (PASSTHROUGH) begin: instr_passthrough if (PASSTHROUGH) begin: instr_passthrough
@ -58,60 +83,60 @@ end else begin: instr_decompress
invalid = 1'b0; invalid = 1'b0;
casez (instr_in[15:0]) casez (instr_in[15:0])
16'h0: invalid = 1'b1; 16'h0: invalid = 1'b1;
RV_C_ADDI4SPN: instr_out = RV_NOZ_ADDI | ({27'h0, rd_s} << RV_RD_LSB) | (5'h2 << RV_RS1_LSB) RV_C_ADDI4SPN: instr_out = RV_NOZ_ADDI | rfmt_rd(rd_s) | rfmt_rs1(5'h2)
| ({instr_in[10:7], instr_in[12:11], instr_in[5], instr_in[6], 2'b00} << 20); | ({instr_in[10:7], instr_in[12:11], instr_in[5], instr_in[6], 2'b00} << 20);
RV_C_LW: instr_out = RV_NOZ_LW | ({27'h0, rd_s} << RV_RD_LSB) | (rs1_s << RV_RS1_LSB) RV_C_LW: instr_out = RV_NOZ_LW | rfmt_rd(rd_s) | rfmt_rs1(rs1_s)
| ({instr_in[5], instr_in[12:10], instr_in[6], 2'b00} << 20); | ({instr_in[5], instr_in[12:10], instr_in[6], 2'b00} << 20);
RV_C_SW: instr_out = RV_NOZ_SW | (rs2_s << RV_RS2_LSB) | (rs1_s << RV_RS1_LSB) RV_C_SW: instr_out = RV_NOZ_SW | rfmt_rs2(rs2_s) | rfmt_rs1(rs1_s)
| ({instr_in[11:10], instr_in[6], 2'b00} << 7) | ({instr_in[5], instr_in[12]} << 25); | ({instr_in[11:10], instr_in[6], 2'b00} << 7) | ({instr_in[5], instr_in[12]} << 25);
RV_C_ADDI: instr_out = RV_NOZ_ADDI | (rd_l << RV_RD_LSB) | (rs1_l << RV_RS1_LSB) | imm_ci; RV_C_ADDI: instr_out = RV_NOZ_ADDI | rfmt_rd(rd_l) | rfmt_rs1(rs1_l) | imm_ci;
RV_C_JAL: instr_out = RV_NOZ_JAL | (5'h1 << RV_RD_LSB) | imm_cj; RV_C_JAL: instr_out = RV_NOZ_JAL | rfmt_rd(5'h1) | imm_cj;
RV_C_J: instr_out = RV_NOZ_JAL | (5'h0 << RV_RD_LSB) | imm_cj; RV_C_J: instr_out = RV_NOZ_JAL | rfmt_rd(5'h0) | imm_cj;
RV_C_LI: instr_out = RV_NOZ_ADDI | (rd_l << RV_RD_LSB) | imm_ci; RV_C_LI: instr_out = RV_NOZ_ADDI | rfmt_rd(rd_l) | imm_ci;
RV_C_LUI: begin RV_C_LUI: begin
if (rd_l == 5'h2) begin if (rd_l == 5'h2) begin
// addi6sp // addi6sp
instr_out = RV_NOZ_ADDI | (5'h2 << RV_RD_LSB) | (5'h2 << RV_RS1_LSB) | instr_out = RV_NOZ_ADDI | rfmt_rd(5'h2) | rfmt_rs1(5'h2) |
({{3{instr_in[12]}}, instr_in[4:3], instr_in[5], instr_in[2], instr_in[6]} << 24); ({{3{instr_in[12]}}, instr_in[4:3], instr_in[5], instr_in[2], instr_in[6]} << 24);
end else begin end else begin
instr_out = RV_NOZ_LUI | (rd_l << RV_RD_LSB) | ({{15{instr_in[12]}}, instr_in[6:2]} << 12); instr_out = RV_NOZ_LUI | rfmt_rd(rd_l) | ({{15{instr_in[12]}}, instr_in[6:2]} << 12);
end end
invalid = ~|{instr_in[12], instr_in[6:2]}; // RESERVED if imm == 0 invalid = ~|{instr_in[12], instr_in[6:2]}; // RESERVED if imm == 0
end end
RV_C_SLLI: instr_out = RV_NOZ_SLLI | (rs1_l << RV_RD_LSB) | (rs1_l << RV_RS1_LSB) | imm_ci; RV_C_SLLI: instr_out = RV_NOZ_SLLI | rfmt_rd(rs1_l) | rfmt_rs1(rs1_l) | imm_ci;
RV_C_SRAI: instr_out = RV_NOZ_SRAI | (rs1_s << RV_RD_LSB) | (rs1_s << RV_RS1_LSB) | imm_ci; RV_C_SRAI: instr_out = RV_NOZ_SRAI | rfmt_rd(rs1_s) | rfmt_rs1(rs1_s) | imm_ci;
RV_C_SRLI: instr_out = RV_NOZ_SRLI | (rs1_s << RV_RD_LSB) | (rs1_s << RV_RS1_LSB) | imm_ci; RV_C_SRLI: instr_out = RV_NOZ_SRLI | rfmt_rd(rs1_s) | rfmt_rs1(rs1_s) | imm_ci;
RV_C_ANDI: instr_out = RV_NOZ_ANDI | (rs1_s << RV_RD_LSB) | (rs1_s << RV_RS1_LSB) | imm_ci; RV_C_ANDI: instr_out = RV_NOZ_ANDI | rfmt_rd(rs1_s) | rfmt_rs1(rs1_s) | imm_ci;
RV_C_AND: instr_out = RV_NOZ_AND | (rs1_s << RV_RD_LSB) | (rs1_s << RV_RS1_LSB) | (rs2_s << RV_RS2_LSB); RV_C_AND: instr_out = RV_NOZ_AND | rfmt_rd(rs1_s) | rfmt_rs1(rs1_s) | rfmt_rs2(rs2_s);
RV_C_OR: instr_out = RV_NOZ_OR | (rs1_s << RV_RD_LSB) | (rs1_s << RV_RS1_LSB) | (rs2_s << RV_RS2_LSB); RV_C_OR: instr_out = RV_NOZ_OR | rfmt_rd(rs1_s) | rfmt_rs1(rs1_s) | rfmt_rs2(rs2_s);
RV_C_XOR: instr_out = RV_NOZ_XOR | (rs1_s << RV_RD_LSB) | (rs1_s << RV_RS1_LSB) | (rs2_s << RV_RS2_LSB); RV_C_XOR: instr_out = RV_NOZ_XOR | rfmt_rd(rs1_s) | rfmt_rs1(rs1_s) | rfmt_rs2(rs2_s);
RV_C_SUB: instr_out = RV_NOZ_SUB | (rs1_s << RV_RD_LSB) | (rs1_s << RV_RS1_LSB) | (rs2_s << RV_RS2_LSB); RV_C_SUB: instr_out = RV_NOZ_SUB | rfmt_rd(rs1_s) | rfmt_rs1(rs1_s) | rfmt_rs2(rs2_s);
RV_C_ADD: begin RV_C_ADD: begin
if (|rs2_l) begin if (|rs2_l) begin
instr_out = RV_NOZ_ADD | (rd_l << RV_RD_LSB) | (rs1_l << RV_RS1_LSB) | (rs2_l << RV_RS2_LSB); instr_out = RV_NOZ_ADD | rfmt_rd(rd_l) | rfmt_rs1(rs1_l) | rfmt_rs2(rs2_l);
end else if (|rs1_l) begin // jalr end else if (|rs1_l) begin // jalr
instr_out = RV_NOZ_JALR | (5'h1 << RV_RD_LSB) | (rs1_l << RV_RS1_LSB); instr_out = RV_NOZ_JALR | rfmt_rd(5'h1) | rfmt_rs1(rs1_l);
end else begin // ebreak end else begin // ebreak
instr_out = RV_NOZ_EBREAK; instr_out = RV_NOZ_EBREAK;
end end
end end
RV_C_MV: begin RV_C_MV: begin
if (|rs2_l) begin // mv if (|rs2_l) begin // mv
instr_out = RV_NOZ_ADD | (rd_l << RV_RD_LSB) | (rs2_l << RV_RS2_LSB); instr_out = RV_NOZ_ADD | rfmt_rd(rd_l) | rfmt_rs2(rs2_l);
end else begin // jr end else begin // jr
instr_out = RV_NOZ_JALR | (rs1_l << RV_RS1_LSB); instr_out = RV_NOZ_JALR | rfmt_rs1(rs1_l);
invalid = ~|rs1_l; // RESERVED invalid = ~|rs1_l; // RESERVED
end end
end end
RV_C_LWSP: begin RV_C_LWSP: begin
instr_out = RV_NOZ_LW | (rd_l << RV_RD_LSB) | (5'h2 << RV_RS1_LSB) instr_out = RV_NOZ_LW | rfmt_rd(rd_l) | rfmt_rs1(5'h2)
| ({instr_in[3:2], instr_in[12], instr_in[6:4], 2'b00} << 20); | ({instr_in[3:2], instr_in[12], instr_in[6:4], 2'b00} << 20);
invalid = ~|rd_l; // RESERVED invalid = ~|rd_l; // RESERVED
end end
RV_C_SWSP: instr_out = RV_NOZ_SW | (rs2_l << RV_RS2_LSB) | (5'h2 << RV_RS1_LSB) RV_C_SWSP: instr_out = RV_NOZ_SW | rfmt_rs2(rs2_l) | rfmt_rs1(5'h2)
| ({instr_in[11:9], 2'b00} << 7) | ({instr_in[8:7], instr_in[12]} << 25); | ({instr_in[11:9], 2'b00} << 7) | ({instr_in[8:7], instr_in[12]} << 25);
RV_C_BEQZ: instr_out = RV_NOZ_BEQ | (rs1_s << RV_RS1_LSB) | imm_cb; RV_C_BEQZ: instr_out = RV_NOZ_BEQ | rfmt_rs1(rs1_s) | imm_cb;
RV_C_BNEZ: instr_out = RV_NOZ_BNE | (rs1_s << RV_RS1_LSB) | imm_cb; RV_C_BNEZ: instr_out = RV_NOZ_BNE | rfmt_rs1(rs1_s) | imm_cb;
default: invalid = 1'b1; default: invalid = 1'b1;
endcase endcase
end end