From da3d2eedd2b6391621e81b3eaaa28a571e058f9d Mon Sep 17 00:00:00 2001 From: Eddie Hung Date: Tue, 18 Jun 2019 09:49:57 -0700 Subject: [PATCH] Fix (do not) permute LUT inputs, but permute mux selects --- techlibs/xilinx/lut_map.v | 64 ++++++++++++++++++++------------------- 1 file changed, 33 insertions(+), 31 deletions(-) diff --git a/techlibs/xilinx/lut_map.v b/techlibs/xilinx/lut_map.v index 2f246e46d..62ce374df 100644 --- a/techlibs/xilinx/lut_map.v +++ b/techlibs/xilinx/lut_map.v @@ -29,30 +29,32 @@ module \$lut (A, Y); input [WIDTH-1:0] A; output Y; - // Need to swap input ordering, and fix init accordingly, + // Need to swap input ordering of wide LUTs, and fix init accordingly, // to match ABC's expectation of LUT inputs in non-decreasing // delay order function [WIDTH-1:0] permute_index; input [WIDTH-1:0] i; integer j; begin - permute_index = 0; - for (j = 0; j < WIDTH; j = j + 1) - permute_index[WIDTH-1 - j] = i[j]; + if (WIDTH == 7) + permute_index = { i[5:0], i[6] }; + else if (WIDTH == 8) + permute_index = { i[5:0], i[6], i[7] }; + else + permute_index = i; end endfunction function [2**WIDTH-1:0] permute_init; - input [2**WIDTH-1:0] orig; integer i; begin permute_init = 0; for (i = 0; i < 2**WIDTH; i = i + 1) - permute_init[i] = orig[permute_index(i)]; + permute_init[i] = LUT[permute_index(i)]; end endfunction - parameter [2**WIDTH-1:0] P_LUT = permute_init(LUT); + parameter [2**WIDTH-1:0] P_LUT = permute_init(); generate if (WIDTH == 1) begin @@ -61,54 +63,54 @@ module \$lut (A, Y); end else if (WIDTH == 2) begin LUT2 #(.INIT(P_LUT)) _TECHMAP_REPLACE_ (.O(Y), - .I0(A[1]), .I1(A[0])); + .I0(A[0]), .I1(A[1])); end else if (WIDTH == 3) begin LUT3 #(.INIT(P_LUT)) _TECHMAP_REPLACE_ (.O(Y), - .I0(A[2]), .I1(A[1]), .I2(A[0])); + .I0(A[0]), .I1(A[1]), .I2(A[2])); end else if (WIDTH == 4) begin LUT4 #(.INIT(P_LUT)) _TECHMAP_REPLACE_ (.O(Y), - .I0(A[3]), .I1(A[2]), .I2(A[1]), - .I3(A[0])); + .I0(A[0]), .I1(A[1]), .I2(A[2]), + .I3(A[3])); end else if (WIDTH == 5) begin LUT5 #(.INIT(P_LUT)) _TECHMAP_REPLACE_ (.O(Y), - .I0(A[4]), .I1(A[3]), .I2(A[2]), - .I3(A[1]), .I4(A[0])); + .I0(A[0]), .I1(A[1]), .I2(A[2]), + .I3(A[3]), .I4(A[4])); end else if (WIDTH == 6) begin LUT6 #(.INIT(P_LUT)) _TECHMAP_REPLACE_ (.O(Y), - .I0(A[5]), .I1(A[4]), .I2(A[3]), - .I3(A[2]), .I4(A[1]), .I5(A[0])); + .I0(A[0]), .I1(A[1]), .I2(A[2]), + .I3(A[3]), .I4(A[4]), .I5(A[5])); end else if (WIDTH == 7) begin wire T0, T1; LUT6 #(.INIT(P_LUT[63:0])) fpga_lut_0 (.O(T0), - .I0(A[5]), .I1(A[4]), .I2(A[3]), - .I3(A[2]), .I4(A[1]), .I5(A[0])); + .I0(A[1]), .I1(A[2]), .I2(A[3]), + .I3(A[4]), .I4(A[5]), .I5(A[6])); LUT6 #(.INIT(P_LUT[127:64])) fpga_lut_1 (.O(T1), - .I0(A[5]), .I1(A[4]), .I2(A[3]), - .I3(A[2]), .I4(A[1]), .I5(A[0])); - MUXF7 fpga_mux_0 (.O(Y), .I0(T0), .I1(T1), .S(A[6])); + .I0(A[1]), .I1(A[2]), .I2(A[3]), + .I3(A[4]), .I4(A[5]), .I5(A[6])); + MUXF7 fpga_mux_0 (.O(Y), .I0(T0), .I1(T1), .S(A[0])); end else if (WIDTH == 8) begin wire T0, T1, T2, T3, T4, T5; LUT6 #(.INIT(P_LUT[63:0])) fpga_lut_0 (.O(T0), - .I0(A[5]), .I1(A[4]), .I2(A[3]), - .I3(A[2]), .I4(A[1]), .I5(A[0])); + .I0(A[2]), .I1(A[3]), .I2(A[4]), + .I3(A[5]), .I4(A[6]), .I5(A[7])); LUT6 #(.INIT(P_LUT[127:64])) fpga_lut_1 (.O(T1), - .I0(A[5]), .I1(A[4]), .I2(A[3]), - .I3(A[2]), .I4(A[1]), .I5(A[0])); + .I0(A[2]), .I1(A[3]), .I2(A[4]), + .I3(A[5]), .I4(A[6]), .I5(A[7])); LUT6 #(.INIT(P_LUT[191:128])) fpga_lut_2 (.O(T2), - .I0(A[5]), .I1(A[4]), .I2(A[3]), - .I3(A[2]), .I4(A[1]), .I5(A[0])); + .I0(A[2]), .I1(A[3]), .I2(A[4]), + .I3(A[5]), .I4(A[6]), .I5(A[7])); LUT6 #(.INIT(P_LUT[255:192])) fpga_lut_3 (.O(T3), - .I0(A[5]), .I1(A[4]), .I2(A[3]), - .I3(A[2]), .I4(A[1]), .I5(A[0])); - MUXF7 fpga_mux_0 (.O(T4), .I0(T0), .I1(T1), .S(A[6])); - MUXF7 fpga_mux_1 (.O(T5), .I0(T2), .I1(T3), .S(A[6])); - MUXF8 fpga_mux_2 (.O(Y), .I0(T4), .I1(T5), .S(A[7])); + .I0(A[2]), .I1(A[3]), .I2(A[4]), + .I3(A[5]), .I4(A[6]), .I5(A[7])); + MUXF7 fpga_mux_0 (.O(T4), .I0(T0), .I1(T1), .S(A[1])); + MUXF7 fpga_mux_1 (.O(T5), .I0(T2), .I1(T3), .S(A[1])); + MUXF8 fpga_mux_2 (.O(Y), .I0(T4), .I1(T5), .S(A[0])); end else begin wire _TECHMAP_FAIL_ = 1; end -- 2.30.2