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Code Activity

Added $shift and $shiftx cell types (needed for correct part select behavior)

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This commit is contained in:
Clifford Wolf 2014-07-29 14:42:33 +02:00
parent 48822e79a3
commit 397b00252d
12 changed files with 214 additions and 40 deletions
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48
techlibs/common/simlib.v
View file

@ -418,6 +418,54 @@ endmodule
// --------------------------------------------------------
module \$shift (A, B, Y);
parameter A_SIGNED = 0;
parameter B_SIGNED = 0;
parameter A_WIDTH = 0;
parameter B_WIDTH = 0;
parameter Y_WIDTH = 0;
input [A_WIDTH-1:0] A;
input [B_WIDTH-1:0] B;
output [Y_WIDTH-1:0] Y;
generate
if (B_SIGNED) begin:BLOCK1
assign Y = $signed(B) < 0 ? A << -B : A >> B;
end else begin:BLOCK2
assign Y = A >> B;
end
endgenerate
endmodule
// --------------------------------------------------------
module \$shiftx (A, B, Y);
parameter A_SIGNED = 0;
parameter B_SIGNED = 0;
parameter A_WIDTH = 0;
parameter B_WIDTH = 0;
parameter Y_WIDTH = 0;
input [A_WIDTH-1:0] A;
input [B_WIDTH-1:0] B;
output [Y_WIDTH-1:0] Y;
generate
if (B_SIGNED) begin:BLOCK1
assign Y = A[$signed(B) +: Y_WIDTH];
end else begin:BLOCK2
assign Y = A[B +: Y_WIDTH];
end
endgenerate
endmodule
// --------------------------------------------------------
module \$lt (A, B, Y);
parameter A_SIGNED = 0;

72
techlibs/common/stdcells.v
View file

@ -129,12 +129,12 @@ endmodule
// --------------------------------------------------------
module \$__shift (X, A, Y);
module \$__shift (XL, XR, A, Y);
parameter WIDTH = 1;
parameter SHIFT = 0;
input X;
input XL, XR;
input [WIDTH-1:0] A;
output [WIDTH-1:0] Y;
@ -142,12 +142,12 @@ genvar i;
generate
for (i = 0; i < WIDTH; i = i + 1) begin:V
if (i+SHIFT < 0) begin
assign Y[i] = 0;
assign Y[i] = XR;
end else
if (i+SHIFT < WIDTH) begin
assign Y[i] = A[i+SHIFT];
end else begin
assign Y[i] = X;
assign Y[i] = XL;
end
end
endgenerate
@ -196,7 +196,8 @@ generate
.WIDTH(WIDTH),
.SHIFT(0 - (2 ** (i > 30 ? 30 : i)))
) sh (
.X(0),
.XL(1'b0),
.XR(1'b0),
.A(unshifted),
.Y(shifted)
);
@ -255,7 +256,8 @@ generate
.WIDTH(WIDTH),
.SHIFT(2 ** (i > 30 ? 30 : i))
) sh (
.X(0),
.XL(1'b0),
.XR(1'b0),
.A(unshifted),
.Y(shifted)
);
@ -314,7 +316,8 @@ generate
.WIDTH(WIDTH),
.SHIFT(0 - (2 ** (i > 30 ? 30 : i)))
) sh (
.X(0),
.XL(1'b0),
.XR(1'b0),
.A(unshifted),
.Y(shifted)
);
@ -382,7 +385,8 @@ generate
.WIDTH(WIDTH),
.SHIFT(2 ** (i > 30 ? 30 : i))
) sh (
.X(A_SIGNED && A[A_WIDTH-1]),
.XL(A_SIGNED && A[A_WIDTH-1]),
.XR(1'b0),
.A(unshifted),
.Y(shifted)
);
@ -401,6 +405,58 @@ endmodule
// --------------------------------------------------------
module \$shift (A, B, Y);
parameter A_SIGNED = 0;
parameter B_SIGNED = 0;
parameter A_WIDTH = 1;
parameter B_WIDTH = 1;
parameter Y_WIDTH = 1;
input [A_WIDTH-1:0] A;
input [B_WIDTH-1:0] B;
output [Y_WIDTH-1:0] Y;
generate
if (B_SIGNED) begin:BLOCK1
assign Y = $signed(B) < 0 ? A << -B : A >> B;
end else begin:BLOCK2
assign Y = A >> B;
end
endgenerate
endmodule
// --------------------------------------------------------
module \$shiftx (A, B, Y);
parameter A_SIGNED = 0;
parameter B_SIGNED = 0;
parameter A_WIDTH = 1;
parameter B_WIDTH = 1;
parameter Y_WIDTH = 1;
input [A_WIDTH-1:0] A;
input [B_WIDTH-1:0] B;
output [Y_WIDTH-1:0] Y;
\$shift #(
.A_SIGNED(A_SIGNED),
.B_SIGNED(B_SIGNED),
.A_WIDTH(A_WIDTH),
.B_WIDTH(B_WIDTH),
.Y_WIDTH(Y_WIDTH),
) sh (
.A(A),
.B(B),
.Y(Y)
);
endmodule
// --------------------------------------------------------
module \$__fulladd (A, B, C, X, Y);
// {X, Y} = A + B + C