tests/test.sh exit code (0 → resolved); the classification below is post-hoc and cannot change it.module TopModule(
input clk,
input rst_n,
input start,
input [127:0] block_in,
input [127:0] round_key0,
input [3:0] num_rounds,
input reseed,
input [3:0] reseed_round,
output reg ready,
output reg result_valid,
output reg [127:0] block_out
);
// engine registers
reg [127:0] state;
reg [127:0] key;
reg [3:0] nrounds;
reg [3:0] ridx; // completed-rounds counter / current round index
reg [4:0] slot; // 0..15 byte slots, 16 = key-mix slot
reg [7:0] fb; // feedback: start feedback at slot 0, else previous byte
reg busy;
// combinational byte-slot computation
// byte lane k for slot i = 4*(i>>2) + 3 - (i&3)
wire [4:0] k = {slot[3:2], 2'b00} + 5'd3 - {3'b000, slot[1:0]};
wire [7:0] obyte = state[k*8 +: 8];
wire [7:0] xored = obyte ^ fb;
wire [7:0] rolled = {xored[6:0], xored[7]}; // rol1
wire [7:0] newb = rolled ^ 8'h63;
always @(posedge clk) begin
if (!rst_n) begin
ready <= 1'b1;
result_valid <= 1'b0;
block_out <= 128'b0;
busy <= 1'b0;
state <= 128'b0;
key <= 128'b0;
nrounds <= 4'b0;
ridx <= 4'b0;
slot <= 5'b0;
fb <= 8'b0;
end else begin
if (ready && start) begin
// load a new operation
state <= block_in;
key <= round_key0;
nrounds <= num_rounds;
ridx <= 4'b0;
slot <= 5'b0;
fb <= 8'b0; // round 0 start feedback = {4'b0, round_index=0}
ready <= 1'b0;
result_valid <= 1'b0;
busy <= 1'b1;
end else if (busy) begin
if (slot < 5'd16) begin
// byte slot: replace only this byte
state[k*8 +: 8] <= newb;
fb <= newb; // becomes next slot's feedback
slot <= slot + 5'd1;
end else begin
// key-mix slot
state <= state ^ key;
if (ridx == nrounds - 4'd1) begin
// finishing slot
block_out <= state ^ key;
result_valid <= 1'b1;
ready <= 1'b1;
busy <= 1'b0;
end else begin
// set up next round; fix its start feedback here
ridx <= ridx + 4'd1;
slot <= 5'b0;
fb <= reseed ? {4'b0, reseed_round}
: {4'b0, (ridx + 4'd1)};
end
end
end
end
end
endmodule
Compile check with iverilog
iverilog -g2012 -o /tmp/dut_test dut.sv 2>&1 && echo "COMPILE OK" || echo "no iverilog or error"
COMPILE OK [stdout] COMPILE OK
Simulate with independent reference model
cat > /tmp/tb.sv <<'EOF'
module tb;
reg clk=0, rst_n=0, start=0, reseed=0;
reg [127:0] block_in, round_key0;
reg [3:0] num_rounds, reseed_round;
wire ready, result_valid;
wire [127:0] block_out;
TopModule dut(.clk(clk),.rst_n(rst_n),.start(start),.block_in(block_in),
.round_key0(round_key0),.num_rounds(num_rounds),.reseed(reseed),
.reseed_round(reseed_round),.ready(ready),.result_valid(result_valid),
.block_out(block_out));
always #5 clk=~clk;
// reference model
function [7:0] rol1(input [7:0] x); rol1={x[6:0],x[7]}; endfunction
reg [127:0] ref_model;
integer r,i,kk,cyc;
reg [7:0] feed, ob, nb;
task compute_ref;
input [127:0] bin; input [127:0] key; input [3:0] nr;
input rs; input [3:0] rr;
begin
ref_model = bin;
for (r=0;r<nr;r=r+1) begin
if (r==0) feed = 8'h00;
else feed = rs ? {4'b0,rr} : {4'b0,r[3:0]};
for (i=0;i<16;i=i+1) begin
kk = 4*(i/4) + 3 - (i%4);
ob = ref_model[kk*8 +: 8];
nb = rol1(ob ^ feed) ^ 8'h63;
ref_model[kk*8 +: 8] = nb;
feed = nb;
end
ref_model = ref_model ^ key;
end
end
endtask
initial begin
@(negedge clk); rst_n=1;
// test 1: num_rounds=1, no reseed
block_in=128'h0123456789abcdef_fedcba9876543210;
round_key0=128'hdeadbeefcafebabe_0011223344556677;
num_rounds=3; reseed=0; reseed_round=0;
@(negedge clk); start=1;
@(negedge clk); start=0;
cyc=0;
while(!result_valid && cyc<200) begin @(negedge clk); cyc=cyc+1; end
compute_ref(128'h0123456789abcdef_fedcba9876543210,
128'hdeadbeefcafebabe_0011223344556677,3,0,0);
$display("latency(after start cycle) cyc=%0d (expect 17*3=51)",cyc);
if (block_out===ref_model) $display("TEST1 PASS out=%h",block_out);
else $display("TEST1 FAIL got=%h exp=%h",block_out,ref_model);
if (ready!==1'b1) $display("READY not high at finish!");
// test 2 with reseed
@(negedge clk);
block_in=128'hffeeddccbbaa9988_7766554433221100;
round_key0=128'h00000000000000000000000000000001;
num_rounds=4; reseed=1; reseed_round=4'ha;
@(negedge clk); start=1; @(negedge clk); start=0;
while(!result_valid) @(negedge clk);
compute_ref(128'hffeeddccbbaa9988_7766554433221100,
128'h00000000000000000000000000000001,4,1,4'ha);
if (block_out===ref_model) $display("TEST2 PASS out=%h",block_out);
else $display("TEST2 FAIL got=%h exp=%h",block_out,ref_model);
$finish;
end
endmodule
EOF
iverilog -g2012 -o /tmp/sim /app/dut.sv /tmp/tb.sv 2>&1 && vvp /tmp/simlatency(after start cycle) cyc=51 (expect 17*3=51) TEST1 PASS out=50ae8d1a10eb939c73c1a0314683b79d TEST2 PASS out=d748aeeab45c0154c659bffb6c4499cc /tmp/tb.sv:69: $finish called at 1250 (1s) [stdout] latency(after start cycle) cyc=51 (expect 17*3=51) TEST1 PASS out=50ae8d1a10eb939c73c1a0314683b79d TEST2 PASS out=d748aeeab45c0154c659bffb6c4499cc /tmp/tb.sv:69: $finish called at 1250 (1s)
No file changes, the agent left the workspace untouched.
TEST dut_present: PASS (/app/dut.sv exists)
TEST dut_forbidden: PASS (no forbidden constructs)
TEST dut_elaborates: PASS (DUT elaborates standalone)
TEST dut_compiles: PASS (compiled with held-back reference/testbench)
TEST simulation_completed: PASS (Mismatches: 794 in 16537 samples)
TEST reference_equivalence: FAIL (794 mismatches in 16537 samples)
{"score": 0.000000, "results_file": "/tmp/h2t-grader-home.x7eKjY/runtime/cb_verifier_312-18500-24441-28065_312/results.jsonl"}Reproduce this trial: git checkout 2f94510 && PYTHONPATH=src python3 scripts/build_site.py , then open trial/trial_b7be3f19d23d4c1d. Re-running the agent live requires EVAL_PLATFORM_ENABLE_OAUTH_SMOKE=1 and is non-deterministic.
Trial trial_b7be3f19d23d4c1d · verifier authoritative; classifier explanatory.