From de37070c28c08e1d7a5e18f8c65e4837f51c9e40 Mon Sep 17 00:00:00 2001 From: Gus Smith Date: Wed, 22 Jun 2022 10:57:46 -0700 Subject: [PATCH 1/4] Support param. default values in JSON FE and SV BE --- backends/verilog/verilog_backend.cc | 11 +++++++++++ frontends/json/jsonparse.cc | 3 +++ 2 files changed, 14 insertions(+) diff --git a/backends/verilog/verilog_backend.cc b/backends/verilog/verilog_backend.cc index aa1d4558c..28cbb4f4d 100644 --- a/backends/verilog/verilog_backend.cc +++ b/backends/verilog/verilog_backend.cc @@ -395,6 +395,14 @@ void dump_attributes(std::ostream &f, std::string indent, dictattributes, '\n', /*modattr=*/false, /*regattr=*/reg_wires.count(wire->name)); @@ -2084,6 +2092,9 @@ void dump_module(std::ostream &f, std::string indent, RTLIL::Module *module) f << indent + " " << "reg " << id(initial_id) << " = 0;\n"; } + for (auto p : module->parameter_default_values) + dump_parameter(f, indent + " ", p.first, p.second); + for (auto w : module->wires()) dump_wire(f, indent + " ", w); diff --git a/frontends/json/jsonparse.cc b/frontends/json/jsonparse.cc index 1aab81015..96c2d3d77 100644 --- a/frontends/json/jsonparse.cc +++ b/frontends/json/jsonparse.cc @@ -302,6 +302,9 @@ void json_import(Design *design, string &modname, JsonNode *node) if (node->data_dict.count("attributes")) json_parse_attr_param(module->attributes, node->data_dict.at("attributes")); + if (node->data_dict.count("parameter_default_values")) + json_parse_attr_param(module->parameter_default_values, node->data_dict.at("parameter_default_values")); + dict signal_bits; if (node->data_dict.count("ports")) From 3d738f86573993fa848a5a67a6177ac8520d03a8 Mon Sep 17 00:00:00 2001 From: Gus Smith Date: Tue, 6 Jan 2026 09:37:13 -0800 Subject: [PATCH 2/4] Update backends/verilog/verilog_backend.cc MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Co-authored-by: Marcelina Kościelnicka <236399+mwkmwkmwk@users.noreply.github.com> --- backends/verilog/verilog_backend.cc | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/backends/verilog/verilog_backend.cc b/backends/verilog/verilog_backend.cc index 28cbb4f4d..84b1ce97d 100644 --- a/backends/verilog/verilog_backend.cc +++ b/backends/verilog/verilog_backend.cc @@ -400,7 +400,7 @@ void dump_parameter(std::ostream &f, std::string indent, RTLIL::IdString id_stri f << stringf("%sparameter %s", indent.c_str(), id(id_string).c_str()); f << stringf(" = "); dump_const(f, parameter); - f << stringf(";\n"); + f << ";\n"; } void dump_wire(std::ostream &f, std::string indent, RTLIL::Wire *wire) From 9635e1f0d4c0d86d0c30eeda96a3e7e4e1e017d7 Mon Sep 17 00:00:00 2001 From: Gus Smith Date: Tue, 6 Jan 2026 09:37:21 -0800 Subject: [PATCH 3/4] Update backends/verilog/verilog_backend.cc MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Co-authored-by: Marcelina Kościelnicka <236399+mwkmwkmwk@users.noreply.github.com> --- backends/verilog/verilog_backend.cc | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/backends/verilog/verilog_backend.cc b/backends/verilog/verilog_backend.cc index 84b1ce97d..aaad5787b 100644 --- a/backends/verilog/verilog_backend.cc +++ b/backends/verilog/verilog_backend.cc @@ -397,8 +397,7 @@ void dump_attributes(std::ostream &f, std::string indent, dict Date: Tue, 6 Jan 2026 10:38:03 -0800 Subject: [PATCH 4/4] Add tests --- tests/various/json_param_defaults.v | 10 ++++++++++ tests/various/json_param_defaults.ys | 8 ++++++++ 2 files changed, 18 insertions(+) create mode 100644 tests/various/json_param_defaults.v create mode 100644 tests/various/json_param_defaults.ys diff --git a/tests/various/json_param_defaults.v b/tests/various/json_param_defaults.v new file mode 100644 index 000000000..7d3b94a68 --- /dev/null +++ b/tests/various/json_param_defaults.v @@ -0,0 +1,10 @@ +module json_param_defaults #( + parameter WIDTH = 8, + parameter SIGNED = 1 +) ( + input [WIDTH-1:0] a, + output [WIDTH-1:0] y +); + wire [WIDTH-1:0] y_int = a << SIGNED; + assign y = y_int; +endmodule diff --git a/tests/various/json_param_defaults.ys b/tests/various/json_param_defaults.ys new file mode 100644 index 000000000..2624ab884 --- /dev/null +++ b/tests/various/json_param_defaults.ys @@ -0,0 +1,8 @@ +! mkdir -p temp +read_verilog -sv json_param_defaults.v +write_json temp/json_param_defaults.json +design -reset +read_json temp/json_param_defaults.json +write_verilog -noattr temp/json_param_defaults.v +! grep -qF "parameter WIDTH = 32'd8" temp/json_param_defaults.v +! grep -qF "parameter SIGNED = 32'd1" temp/json_param_defaults.v