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Reduce number of decomposed muxes during techmap

This commit is contained in:
Eddie Hung 2019-06-24 14:28:56 -07:00
parent 2e7992efff
commit db6a0b72b2
1 changed files with 11 additions and 14 deletions
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25
techlibs/xilinx/cells_map.v
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@ -225,7 +225,7 @@ module \$__XILINX_SHIFTX (A, B, Y);
else if (A_WIDTH <= 2 ** 4) begin
localparam a_width0 = 2 ** 2;
localparam num_mux8 = A_WIDTH / a_width0;
localparam a_widthN = A_WIDTH - num_mux8*a_width0;
localparam a_widthN = A_WIDTH % a_width0;
wire [a_width0-1:0] T;
for (i = 0; i < a_width0; i++)
if (i < num_mux8)
@ -243,20 +243,17 @@ module \$__XILINX_SHIFTX (A, B, Y);
else begin
localparam a_width0 = 2 ** 4;
localparam num_mux16 = A_WIDTH / a_width0;
localparam a_widthN = A_WIDTH - num_mux16*a_width0;
wire [a_width0-1:0] T;
for (i = 0; i < a_width0; i++)
if (i < num_mux16)
\$__XILINX_SHIFTX #(.A_SIGNED(A_SIGNED), .B_SIGNED(B_SIGNED), .A_WIDTH(a_width0), .B_WIDTH(4), .Y_WIDTH(Y_WIDTH)) fpga_soft_mux (.A(A[i*a_width0+:a_width0]), .B(B[4-1:0]), .Y(T[i]));
else if (i == num_mux16 && a_widthN > 0) begin
if (a_widthN > 1)
\$__XILINX_SHIFTX #(.A_SIGNED(A_SIGNED), .B_SIGNED(B_SIGNED), .A_WIDTH(a_widthN), .B_WIDTH($clog2(a_widthN)), .Y_WIDTH(Y_WIDTH)) fpga_soft_mux_last (.A(A[A_WIDTH-1-:a_widthN]), .B(B[$clog2(a_widthN)-1:0]), .Y(T[i]));
else
assign T[i] = A[A_WIDTH-1];
end
localparam a_widthN = A_WIDTH % a_width0;
wire [num_mux16 + (a_widthN > 0 ? 1 : 0) - 1:0] T;
for (i = 0; i < num_mux16; i++)
\$__XILINX_SHIFTX #(.A_SIGNED(A_SIGNED), .B_SIGNED(B_SIGNED), .A_WIDTH(a_width0), .B_WIDTH(4), .Y_WIDTH(Y_WIDTH)) fpga_soft_mux (.A(A[i*a_width0+:a_width0]), .B(B[4-1:0]), .Y(T[i]));
if (a_widthN > 0) begin
if (a_widthN > 1)
\$__XILINX_SHIFTX #(.A_SIGNED(A_SIGNED), .B_SIGNED(B_SIGNED), .A_WIDTH(a_widthN), .B_WIDTH($clog2(a_widthN)), .Y_WIDTH(Y_WIDTH)) fpga_soft_mux_last (.A(A[A_WIDTH-1-:a_widthN]), .B(B[$clog2(a_widthN)-1:0]), .Y(T[num_mux16]));
else
assign T[i] = 1'bx;
\$__XILINX_SHIFTX #(.A_SIGNED(A_SIGNED), .B_SIGNED(B_SIGNED), .A_WIDTH(2**(B_WIDTH-4)), .B_WIDTH(B_WIDTH-4), .Y_WIDTH(Y_WIDTH)) _TECHMAP_REPLACE_ (.A(T), .B(B[B_WIDTH-1:4]), .Y(Y));
assign T[num_mux16] = A[A_WIDTH-1];
end
\$__XILINX_SHIFTX #(.A_SIGNED(A_SIGNED), .B_SIGNED(B_SIGNED), .A_WIDTH(num_mux16 + (a_widthN > 0 ? 1 : 0)), .B_WIDTH(B_WIDTH-4), .Y_WIDTH(Y_WIDTH)) _TECHMAP_REPLACE_ (.A(T), .B(B[B_WIDTH-1:4]), .Y(Y));
end
endgenerate
endmodule