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-rw-r--r--backends/firrtl/firrtl.cc139
1 files changed, 122 insertions, 17 deletions
diff --git a/backends/firrtl/firrtl.cc b/backends/firrtl/firrtl.cc
index 4f56f498c..14fae1a83 100644
--- a/backends/firrtl/firrtl.cc
+++ b/backends/firrtl/firrtl.cc
@@ -28,10 +28,32 @@
USING_YOSYS_NAMESPACE
PRIVATE_NAMESPACE_BEGIN
+bool defparam, noattr;
pool<string> used_names;
dict<IdString, string> namecache;
int autoid_counter;
+typedef unsigned FDirection;
+static const FDirection NODIRECTION = 0x0;
+static const FDirection IN = 0x1;
+static const FDirection OUT = 0x2;
+static const FDirection INOUT = 0x3;
+
+// Get a port direction with respect to a specific module.
+FDirection getPortFDirection(IdString id, Module *module)
+{
+ Wire *wire = module->wires_.at(id);
+ FDirection direction = NODIRECTION;
+ if (wire && wire->port_id)
+ {
+ if (wire->port_input)
+ direction |= IN;
+ if (wire->port_output)
+ direction |= OUT;
+ }
+ return direction;
+}
+
string next_id()
{
string new_id;
@@ -77,6 +99,8 @@ struct FirrtlWorker
dict<SigBit, pair<string, int>> reverse_wire_map;
string unconn_id;
+ RTLIL::Design *design;
+ std::string indent;
void register_reverse_wire_map(string id, SigSpec sig)
{
@@ -84,11 +108,11 @@ struct FirrtlWorker
reverse_wire_map[sig[i]] = make_pair(id, i);
}
- FirrtlWorker(Module *module, std::ostream &f) : module(module), f(f)
+ FirrtlWorker(Module *module, std::ostream &f, RTLIL::Design *theDesign) : module(module), f(f), design(theDesign), indent(" ")
{
}
- string make_expr(SigSpec sig)
+ string make_expr(const SigSpec &sig)
{
string expr;
@@ -135,6 +159,74 @@ struct FirrtlWorker
return expr;
}
+ std::string fid(RTLIL::IdString internal_id)
+ {
+ const char *str = internal_id.c_str();
+ return *str == '\\' ? str + 1 : str;
+ }
+
+
+ std::string cellname(RTLIL::Cell *cell)
+ {
+ return fid(cell->name).c_str();
+ }
+
+ void process_instance(RTLIL::Cell *cell, vector<string> &wire_exprs)
+ {
+ // TODO: Deal with cell attributes
+ if (!noattr && !cell->attributes.empty()) {
+
+ }
+ std::string cell_type = fid(cell->type);
+
+ // TODO: Deal with cell parameters
+ if (!defparam && cell->parameters.size() > 0) {
+
+ }
+
+ std::string cell_name = cellname(cell);
+ std::string cell_name_comment;
+ if (cell_name != fid(cell->name))
+ cell_name_comment = " /* " + fid(cell->name) + " */ ";
+ else
+ cell_name_comment = "";
+ // Find the module corresponding to this instance.
+ auto instModule = design->module(cell->type);
+ wire_exprs.push_back(stringf("%s" "inst %s%s of %s", indent.c_str(), cell_name.c_str(), cell_name_comment.c_str(), cell_type.c_str()));
+
+ for (auto it = cell->connections().begin(); it != cell->connections().end(); ++it) {
+ if (it->second.size() > 0) {
+ const SigSpec &secondSig = it->second;
+ const std::string firstName = cell_name + "." + make_id(it->first);
+ const std::string secondName = make_expr(secondSig);
+ // Find the direction for this port.
+ FDirection dir = getPortFDirection(it->first, instModule);
+ std::string source, sink;
+ switch (dir) {
+ case INOUT:
+ log_warning("Instance port connection %s.%s is INOUT; treating as OUT\n", log_id(cell_type), log_signal(it->second));
+ case OUT:
+ source = firstName;
+ sink = secondName;
+ break;
+ case NODIRECTION:
+ log_warning("Instance port connection %s.%s is NODIRECTION; treating as IN\n", log_id(cell_type), log_signal(it->second));
+ /* FALL_THROUGH */
+ case IN:
+ source = secondName;
+ sink = firstName;
+ break;
+ default:
+ log_error("Instance port %s.%s unrecognized connection direction 0x%x !\n", log_id(cell_type), log_signal(it->second), dir);
+ break;
+ }
+ wire_exprs.push_back(stringf("\n%s%s <= %s", indent.c_str(), sink.c_str(), source.c_str()));
+ }
+ }
+ wire_exprs.push_back(stringf("\n"));
+
+ }
+
void run()
{
f << stringf(" module %s:\n", make_id(module->name));
@@ -142,21 +234,28 @@ struct FirrtlWorker
for (auto wire : module->wires())
{
+ const auto wireName = make_id(wire->name);
if (wire->port_id)
{
if (wire->port_input && wire->port_output)
log_error("Module port %s.%s is inout!\n", log_id(module), log_id(wire));
port_decls.push_back(stringf(" %s %s: UInt<%d>\n", wire->port_input ? "input" : "output",
- make_id(wire->name), wire->width));
+ wireName, wire->width));
}
else
{
- wire_decls.push_back(stringf(" wire %s: UInt<%d>\n", make_id(wire->name), wire->width));
+ wire_decls.push_back(stringf(" wire %s: UInt<%d>\n", wireName, wire->width));
}
}
for (auto cell : module->cells())
{
+ // Is this cell is a module instance?
+ if (cell->type[0] != '$')
+ {
+ process_instance(cell, wire_exprs);
+ continue;
+ }
if (cell->type.in("$not", "$logic_not", "$neg", "$reduce_and", "$reduce_or", "$reduce_xor", "$reduce_bool", "$reduce_xnor"))
{
string y_id = make_id(cell->name);
@@ -169,7 +268,10 @@ struct FirrtlWorker
a_expr = "asSInt(" + a_expr + ")";
}
- a_expr = stringf("pad(%s, %d)", a_expr.c_str(), y_width);
+ // Don't use the results of logical operations (a single bit) to control padding
+ if (!(cell->type.in("$eq", "$eqx", "$gt", "$ge", "$lt", "$le", "$ne", "$nex", "$reduce_bool", "$logic_not") && y_width == 1) ) {
+ a_expr = stringf("pad(%s, %d)", a_expr.c_str(), y_width);
+ }
string primop;
bool always_uint = false;
@@ -187,9 +289,12 @@ struct FirrtlWorker
a_expr = stringf("xorr(%s)", a_expr.c_str());
}
if (cell->type == "$reduce_bool") {
- primop = "neq";
- a_expr = stringf("%s, UInt(0)", a_expr.c_str());
- }
+ primop = "neq";
+ // Use the sign of the a_expr and its width as the type (UInt/SInt) and width of the comparand.
+ bool a_signed = cell->parameters.at("\\A_SIGNED").as_bool();
+ int a_width = cell->parameters.at("\\A_WIDTH").as_int();
+ a_expr = stringf("%s, %cInt<%d>(0)", a_expr.c_str(), a_signed ? 'S' : 'U', a_width);
+ }
string expr = stringf("%s(%s)", primop.c_str(), a_expr.c_str());
@@ -215,16 +320,16 @@ struct FirrtlWorker
if (cell->parameters.at("\\A_SIGNED").as_bool()) {
a_expr = "asSInt(" + a_expr + ")";
}
- if (cell->parameters.at("\\A_SIGNED").as_bool() & (cell->type != "$shr")) {
- b_expr = "asSInt(" + b_expr + ")";
+ // Shift amount is always unsigned, and needn't be padded to result width.
+ if (!cell->type.in("$shr", "$sshr", "$shl", "$sshl")) {
+ if (cell->parameters.at("\\B_SIGNED").as_bool()) {
+ b_expr = "asSInt(" + b_expr + ")";
+ }
+ b_expr = stringf("pad(%s, %d)", b_expr.c_str(), y_width);
}
a_expr = stringf("pad(%s, %d)", a_expr.c_str(), y_width);
- if ((cell->type != "$shl") && (cell->type != "$sshl")) {
- b_expr = stringf("pad(%s, %d)", b_expr.c_str(), y_width);
- }
-
if (cell->parameters.at("\\A_SIGNED").as_bool() & (cell->type == "$shr")) {
a_expr = "asUInt(" + a_expr + ")";
}
@@ -494,14 +599,14 @@ struct FirrtlWorker
if (is_valid) {
if (make_unconn_id) {
wire_decls.push_back(stringf(" wire %s: UInt<1>\n", unconn_id.c_str()));
- cell_exprs.push_back(stringf(" %s is invalid\n", unconn_id.c_str()));
+ wire_decls.push_back(stringf(" %s is invalid\n", unconn_id.c_str()));
}
wire_exprs.push_back(stringf(" %s <= %s\n", make_id(wire->name), expr.c_str()));
} else {
if (make_unconn_id) {
unconn_id.clear();
}
- wire_exprs.push_back(stringf(" %s is invalid\n", make_id(wire->name)));
+ wire_decls.push_back(stringf(" %s is invalid\n", make_id(wire->name)));
}
}
@@ -570,7 +675,7 @@ struct FirrtlBackend : public Backend {
for (auto module : design->modules())
{
- FirrtlWorker worker(module, *f);
+ FirrtlWorker worker(module, *f, design);
worker.run();
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-11 08:21:18 +0000