mirrors/yosys
3
0
Fork 0
mirror of https://github.com/YosysHQ/yosys synced 2026-06-17 14:26:22 +00:00
Code Activity

Merge pull request #5958 from YosysHQ/emil/opt_muxtree-single-driver

Browse source 
opt_muxtree: error on multiple drivers
This commit is contained in:
Emil J 2026-06-15 15:00:48 +00:00 • committed by GitHub
commit f33cc39a0c
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
2 changed files with 15 additions and 38 deletions
Download patch file Download diff file Expand all files Collapse all files

25
passes/opt/opt_muxtree.cc
View file

@ -68,7 +68,7 @@ struct OptMuxtreeWorker
// Is bit directly used by non-mux cells or ports?
bool seen_non_mux;
pool<int> mux_users;
pool<int> mux_drivers;
std::optional<int> mux_driver;
};
idict<SigBit> bit2num;
@ -107,7 +107,7 @@ struct OptMuxtreeWorker
// Populate bit2info[]:
// .seen_non_mux
// .mux_users
// .mux_drivers
// .mux_driver
// Populate mux2info[].ports[]:
// .ctrl_sig
// .input_sigs
@ -137,8 +137,11 @@ struct OptMuxtreeWorker
// Analyze port A
muxinfo.ports.push_back(used_port_bit(sig_a, this_mux_idx));
for (int idx : sig2bits(sig_y))
bit2info[idx].mux_drivers.insert(this_mux_idx);
for (int idx : sig2bits(sig_y)) {
if (bit2info[idx].mux_driver)
log_cmd_error("Cell %s Y port signal %s already driven by %s\n", cell->name, log_signal(sig_y), mux2info[*bit2info[idx].mux_driver].cell->name);
bit2info[idx].mux_driver = this_mux_idx;
}
for (int idx : sig2bits(sig_s))
bit2info[idx].seen_non_mux = true;
@ -170,8 +173,8 @@ struct OptMuxtreeWorker
for (int j : bit2info[i].mux_users)
for (auto &p : mux2info[j].ports) {
if (p.input_sigs.count(i))
for (int k : bit2info[i].mux_drivers)
p.input_muxes.insert(k);
if (bit2info[i].mux_driver)
p.input_muxes.insert(*bit2info[i].mux_driver);
}
}
@ -184,14 +187,14 @@ struct OptMuxtreeWorker
root_muxes.resize(GetSize(mux2info));
for (auto &bi : bit2info) {
for (int i : bi.mux_drivers)
if (bi.mux_driver)
for (int j : bi.mux_users)
mux_to_users[i].insert(j);
mux_to_users[*bi.mux_driver].insert(j);
if (!bi.seen_non_mux)
continue;
for (int mux_idx : bi.mux_drivers) {
root_muxes.at(mux_idx) = true;
root_enable_muxes.at(mux_idx) = true;
if (bi.mux_driver) {
root_muxes.at(*bi.mux_driver) = true;
root_enable_muxes.at(*bi.mux_driver) = true;
}
}

28
tests/hana/test_parse2synthtrans.v
View file

@ -23,33 +23,7 @@ always @(clk or reset) begin
end
endmodule
// test_parse2synthtrans_case_1_test.v
module f2_demultiplexer1_to_4 (out0, out1, out2, out3, in, s1, s0);
output out0, out1, out2, out3;
reg out0, out1, out2, out3;
input in;
input s1, s0;
reg [3:0] encoding;
reg [1:0] state;
always @(encoding) begin
case (encoding)
4'bxx11: state = 1;
4'bx0xx: state = 3;
4'b11xx: state = 4;
4'bx1xx: state = 2;
4'bxx1x: state = 1;
4'bxxx1: state = 0;
default: state = 0;
endcase
end
always @(encoding) begin
case (encoding)
4'b0000: state = 1;
default: state = 0;
endcase
end
endmodule
// test_parse2synthtrans_case_1_test.v module f2_demultiplexer1_to_4 - REMOVED, multiple drivers
// test_parse2synthtrans_contassign_1_test.v
module f3_test(in, out);