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id_queue: Simplify existence lookup for Verilator speed-up #258

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Merged
merged 3 commits into from
Jun 20, 2025
Merged

id_queue: Simplify existence lookup for Verilator speed-up #258

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57e1306
id_queue: Simplify existence lookup for Verilator speed-up
MaxWipfli Jun 20, 2025
483f059
id_queue: Use bit-wise instead of logical operators
MaxWipfli Jun 20, 2025
18ed5d3
id_queue: Fix formatting
MaxWipfli Jun 20, 2025
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21 changes: 5 additions & 16 deletions src/id_queue.sv
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Original file line number Diff line number Diff line change
Expand Up @@ -362,22 +362,11 @@ module id_queue #(
// Exists Lookup
for (genvar k = 0; k < NUM_CMP_PORTS; k++) begin: gen_lookup_port
for (genvar i = 0; i < CAPACITY; i++) begin: gen_lookup
data_t exists_match_bits;
for (genvar j = 0; j < $bits(data_t); j++) begin: gen_mask
always_comb begin
if (linked_data_q[i].free) begin
exists_match_bits[j] = 1'b0;
end else begin
if (!exists_mask_i[k][j]) begin
exists_match_bits[j] = 1'b1;
end else begin
exists_match_bits[j] =
(linked_data_q[i].data[j] == exists_data_i[k][j]);
end
end
end
end
assign exists_match[k][i] = (&exists_match_bits);
// For a match, the entry needs to be occupied AND
// the masked slot data needs to match the masked query data.
assign exists_match[k][i] = ~linked_data_q[i].free &
((linked_data_q[i].data & exists_mask_i[k]) ==
(exists_data_i[k] & exists_mask_i[k]));
end
always_comb begin
exists_gnt_o[k] = 1'b0;
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