mirrors/yosys
3
0
Fork 0
mirror of https://github.com/YosysHQ/yosys synced 2026-05-30 13:56:33 +00:00
Code Activity

check_mem: Add -non-const option

Browse source 
Can identify potentially dangerous addressing, but also prone to false-positives.
This commit is contained in:
Krystine Sherwin 2026-05-29 18:40:24 +12:00
parent 099c664dc9
commit f6327cc444
No known key found for this signature in database
2 changed files with 82 additions and 3 deletions
Download patch file Download diff file Expand all files Collapse all files

20
passes/cmds/check.cc
View file

@ -468,6 +468,7 @@ struct CheckMemPass : public Pass {
"addressing invalid memory."
);
content_root->option("-non-const", "also check non-const address signals (may produce false-positives)");
content_root->option("-assert", "produce a runtime error if any problems are found in the current design");
return true;
@ -476,12 +477,17 @@ struct CheckMemPass : public Pass {
{
int counter = 0;
bool assert_mode = false;
bool nonconst_mode = false;
size_t argidx;
for (argidx = 1; argidx < args.size(); argidx++) {
if (args[argidx] == "-assert") {
assert_mode = true;
continue;
}
if (args[argidx] == "-non-const") {
nonconst_mode = true;
continue;
}
break;
}
@ -506,19 +512,27 @@ struct CheckMemPass : public Pass {
}
}
auto check_addr = [min_addr, max_addr, &counter, module, &mem](SigSpec &addr_sig, const char* access) {
auto check_addr = [min_addr, max_addr, &counter, module, &mem, &nonconst_mode](SigSpec &addr_sig, const char* access) {
if (addr_sig.is_fully_const()) {
auto addr = addr_sig.as_int();
if (addr < min_addr || addr > max_addr) {
log_warning("Mem %s.%s contains entries for addresses %d..%d but %s address %d.\n", log_id(module), log_id(mem.mem), min_addr, max_addr, access, addr);
counter++;
}
} else {
// TODO test variable addresses? may need sat solver
} else if (nonconst_mode) {
// TODO check addr_sig.has_const() for constant MSb/LSb that may change effective min/max
// TODO consider sat solver for variable addresses
int addr_sig_min = 0;
int addr_sig_max = (1 << addr_sig.size()) - 1;
if (min_addr > addr_sig_min || max_addr < addr_sig_max) {
log_warning("Mem %s.%s contains entries for addresses %d..%d but has a potentially dangerous non-const input %s\n", log_id(module), log_id(mem.mem), min_addr, max_addr, log_signal(addr_sig));
counter++;
}
}
};
// TODO test ABITS and WIDTH?
// TODO can we limit ports via selection?
for (auto &rd_port : mem.rd_ports)
check_addr(rd_port.addr, "reads");
for (auto &wr_port : mem.wr_ports)