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Implemented technology mapping for multipliers (using array multiplier)

This commit is contained in:
Clifford Wolf 2013-06-03 12:48:44 +02:00
parent 21d9251e52
commit 29d6ebd961
1 changed files with 30 additions and 4 deletions
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34
techlibs/stdcells.v
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@ -946,7 +946,26 @@ wire [Y_WIDTH-1:0] A_buf, B_buf;
endmodule endmodule
/**** // --------------------------------------------------------
module \$arraymul (A, B, Y);
parameter WIDTH = 8;
input [WIDTH-1:0] A, B;
output [WIDTH-1:0] Y;
wire [WIDTH*WIDTH-1:0] partials;
genvar i;
assign partials[WIDTH-1 : 0] = A[0] ? B : 0;
generate for (i = 1; i < WIDTH; i = i+1) begin:gen
assign partials[WIDTH*(i+1)-1 : WIDTH*i] = (A[i] ? B << i : 0) + partials[WIDTH*i-1 : WIDTH*(i-1)];
end endgenerate
assign Y = partials[WIDTH*WIDTH-1 : WIDTH*(WIDTH-1)];
endmodule
// -------------------------------------------------------- // --------------------------------------------------------
module \$mul (A, B, Y); module \$mul (A, B, Y);
@ -961,13 +980,20 @@ input [A_WIDTH-1:0] A;
input [B_WIDTH-1:0] B; input [B_WIDTH-1:0] B;
output [Y_WIDTH-1:0] Y; output [Y_WIDTH-1:0] Y;
wire signed [A_WIDTH:0] buffer_a = A_SIGNED ? $signed(A) : A; wire signed [Y_WIDTH:0] buffer_a = A_SIGNED ? $signed(A) : A;
wire signed [B_WIDTH:0] buffer_b = B_SIGNED ? $signed(B) : B; wire signed [Y_WIDTH:0] buffer_b = B_SIGNED ? $signed(B) : B;
assign Y = buffer_a * buffer_b; \$arraymul #(
.WIDTH(Y_WIDTH)
) arraymul (
.A(buffer_a),
.B(buffer_b),
.Y(Y)
);
endmodule endmodule
/****
// -------------------------------------------------------- // --------------------------------------------------------
module \$div (A, B, Y); module \$div (A, B, Y);