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Using maccmap for $macc and $mul techmap

This commit is contained in:
Clifford Wolf 2014-09-07 18:24:08 +02:00
parent c50b841b29
commit dd887cc025
1 changed files with 15 additions and 189 deletions
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204
techlibs/common/techmap.v
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@ -455,102 +455,8 @@ endmodule
// Multiply // Multiply
// -------------------------------------------------------- // --------------------------------------------------------
module \$__acc_set (acc_new, value); (* techmap_maccmap *)
parameter WIDTH = 1; module \$macc ;
output reg [2*WIDTH-1:0] acc_new;
input [WIDTH-1:0] value;
wire [1023:0] _TECHMAP_DO_ = "proc;;;";
integer k;
always @* begin
for (k = 0; k < WIDTH; k = k+1) begin
acc_new[2*k +: 2] = value[k];
end
end
endmodule
module \$__acc_add (acc_new, acc_old, value);
parameter WIDTH = 1;
output reg [2*WIDTH-1:0] acc_new;
input [2*WIDTH-1:0] acc_old;
input [WIDTH-1:0] value;
wire [1023:0] _TECHMAP_DO_ = "proc; simplemap; opt -purge";
integer k;
reg a, b, c;
always @* begin
for (k = 0; k < WIDTH; k = k+1) begin
a = acc_old[2*k];
b = k ? acc_old[2*k-1] : 1'b0;
c = value[k];
acc_new[2*k] = (a ^ b) ^ c;
acc_new[2*k+1] = (a & b) | ((a ^ b) & c);
end
end
endmodule
module \$__acc_get (value, acc);
parameter WIDTH = 1;
output reg [WIDTH-1:0] value;
input [2*WIDTH-1:0] acc;
wire [1023:0] _TECHMAP_DO_ = "proc;;;";
integer k;
always @* begin
// at the end of the multiplier chain the carry-save accumulator
// should also have propagated all carries. thus we just need to
// copy the even bits from the carry accumulator to the output.
for (k = 0; k < WIDTH; k = k+1) begin
value[k] = acc[2*k];
end
end
endmodule
module \$__acc_mul (A, B, Y);
parameter WIDTH = 1;
input [WIDTH-1:0] A, B;
output [WIDTH-1:0] Y;
wire [1023:0] _TECHMAP_DO_ = "proc;;";
integer i;
reg [WIDTH-1:0] x;
reg [2*WIDTH-1:0] y;
(* via_celltype = "\\$__acc_set acc_new" *)
(* via_celltype_defparam_WIDTH = WIDTH *)
function [2*WIDTH-1:0] acc_set;
input [WIDTH-1:0] value;
endfunction
(* via_celltype = "\\$__acc_add acc_new" *)
(* via_celltype_defparam_WIDTH = WIDTH *)
function [2*WIDTH-1:0] acc_add;
input [2*WIDTH-1:0] acc_old;
input [WIDTH-1:0] value;
endfunction
(* via_celltype = "\\$__acc_get value" *)
(* via_celltype_defparam_WIDTH = WIDTH *)
function [WIDTH-1:0] acc_get;
input [2*WIDTH-1:0] acc;
endfunction
always @* begin
x = B;
y = acc_set(A[0] ? x : 1'b0);
for (i = 1; i < WIDTH; i = i+1) begin
x = {x[WIDTH-2:0], 1'b0};
y = acc_add(y, A[i] ? x : 1'b0);
end
end
assign Y = acc_get(y);
endmodule endmodule
module \$mul (A, B, Y); module \$mul (A, B, Y);
@ -566,105 +472,25 @@ module \$mul (A, B, Y);
wire [1023:0] _TECHMAP_DO_ = "RECURSION; CONSTMAP; opt -purge"; wire [1023:0] _TECHMAP_DO_ = "RECURSION; CONSTMAP; opt -purge";
wire [Y_WIDTH-1:0] A_buf, B_buf; localparam [ 3:0] CONFIG_WIDTH_BITS = 15;
\$pos #(.A_SIGNED(A_SIGNED), .A_WIDTH(A_WIDTH), .Y_WIDTH(Y_WIDTH)) A_conv (.A(A), .Y(A_buf)); localparam [ 0:0] CONFIG_IS_SIGNED = A_SIGNED && B_SIGNED;
\$pos #(.A_SIGNED(B_SIGNED), .A_WIDTH(B_WIDTH), .Y_WIDTH(Y_WIDTH)) B_conv (.A(B), .Y(B_buf)); localparam [ 0:0] CONFIG_DO_SUBTRACT = 0;
localparam [14:0] CONFIG_A_WIDTH = A_WIDTH;
localparam [14:0] CONFIG_B_WIDTH = B_WIDTH;
\$__acc_mul #( \$macc #(
.WIDTH(Y_WIDTH) .CONFIG({CONFIG_B_WIDTH, CONFIG_A_WIDTH, CONFIG_DO_SUBTRACT, CONFIG_IS_SIGNED, CONFIG_WIDTH_BITS}),
.CONFIG_WIDTH(15 + 15 + 2 + 4),
.A_WIDTH(B_WIDTH + A_WIDTH),
.B_WIDTH(0),
.Y_WIDTH(Y_WIDTH)
) _TECHMAP_REPLACE_ ( ) _TECHMAP_REPLACE_ (
.A(A_buf), .A({B, A}),
.B(B_buf), .B(),
.Y(Y) .Y(Y)
); );
endmodule endmodule
module \$macc (A, B, Y);
parameter A_WIDTH = 0;
parameter B_WIDTH = 0;
parameter Y_WIDTH = 0;
parameter CONFIG = 4'b0000;
parameter CONFIG_WIDTH = 4;
input [A_WIDTH-1:0] A;
input [B_WIDTH-1:0] B;
output reg [Y_WIDTH-1:0] Y;
wire [1023:0] _TECHMAP_DO_ = "proc; opt -fast";
localparam integer num_bits = CONFIG[3:0];
localparam integer num_ports = (CONFIG_WIDTH-4) / (2 + 2*num_bits);
localparam integer num_abits = $clog2(A_WIDTH) > 0 ? $clog2(A_WIDTH) : 1;
function [2*num_ports*num_abits-1:0] get_port_offsets;
input [CONFIG_WIDTH-1:0] cfg;
integer i, cursor;
begin
cursor = 0;
get_port_offsets = 0;
for (i = 0; i < num_ports; i = i+1) begin
get_port_offsets[(2*i + 0)*num_abits +: num_abits] = cursor;
cursor = cursor + cfg[4 + i*(2 + 2*num_bits) + 2 +: num_bits];
get_port_offsets[(2*i + 1)*num_abits +: num_abits] = cursor;
cursor = cursor + cfg[4 + i*(2 + 2*num_bits) + 2 + num_bits +: num_bits];
end
end
endfunction
localparam [2*num_ports*num_abits-1:0] port_offsets = get_port_offsets(CONFIG);
`define PORT_IS_SIGNED (0 + CONFIG[4 + i*(2 + 2*num_bits)])
`define PORT_DO_SUBTRACT (0 + CONFIG[4 + i*(2 + 2*num_bits) + 1])
`define PORT_SIZE_A (0 + CONFIG[4 + i*(2 + 2*num_bits) + 2 +: num_bits])
`define PORT_SIZE_B (0 + CONFIG[4 + i*(2 + 2*num_bits) + 2 + num_bits +: num_bits])
`define PORT_OFFSET_A (0 + port_offsets[2*i*num_abits +: num_abits])
`define PORT_OFFSET_B (0 + port_offsets[2*i*num_abits + num_abits +: num_abits])
integer i, j;
reg [Y_WIDTH-1:0] tmp_a, tmp_b;
always @* begin
Y = 0;
for (i = 0; i < num_ports; i = i+1)
begin
tmp_a = 0;
tmp_b = 0;
for (j = 0; j < `PORT_SIZE_A; j = j+1)
tmp_a[j] = A[`PORT_OFFSET_A + j];
if (`PORT_IS_SIGNED && `PORT_SIZE_A > 0)
for (j = `PORT_SIZE_A; j < Y_WIDTH; j = j+1)
tmp_a[j] = tmp_a[`PORT_SIZE_A-1];
for (j = 0; j < `PORT_SIZE_B; j = j+1)
tmp_b[j] = A[`PORT_OFFSET_B + j];
if (`PORT_IS_SIGNED && `PORT_SIZE_B > 0)
for (j = `PORT_SIZE_B; j < Y_WIDTH; j = j+1)
tmp_b[j] = tmp_b[`PORT_SIZE_B-1];
if (`PORT_SIZE_B > 0)
tmp_a = tmp_a * tmp_b;
if (`PORT_DO_SUBTRACT)
Y = Y - tmp_a;
else
Y = Y + tmp_a;
end
for (i = 0; i < B_WIDTH; i = i+1) begin
Y = Y + B[i];
end
end
`undef PORT_IS_SIGNED
`undef PORT_DO_SUBTRACT
`undef PORT_SIZE_A
`undef PORT_SIZE_B
`undef PORT_OFFSET_A
`undef PORT_OFFSET_B
endmodule
// -------------------------------------------------------- // --------------------------------------------------------
// Divide and Modulo // Divide and Modulo