From 8a6b0a35207578342c10113b29ca3a303092c37a Mon Sep 17 00:00:00 2001
From: Clifford Wolf <clifford@clifford.at>
Date: Fri, 1 Mar 2013 08:03:00 +0100
Subject: [PATCH] Added help messages to ilang and verilog frontends

---
 README                                |  3 ++
 frontends/ilang/ilang_frontend.cc     | 12 ++++++-
 frontends/verilog/verilog_frontend.cc | 47 ++++++++++++++++++++++++++-
 3 files changed, 60 insertions(+), 2 deletions(-)

diff --git a/README b/README
index 470a32366..7512f7673 100644
--- a/README
+++ b/README
@@ -170,6 +170,9 @@ Verilog Attributes and non-standard features
 - The 'full_case' attribute on case statements is supported
   (also the non-standard "// synopsys full_case" directive)
 
+- The 'parallel_case' attribute on case statements is supported
+  (also the non-standard "// synopsys parallel_case" directive)
+
 - The "// synopsys translate_off" and "// synopsys translate_on"
   directives are also supported (but the use of `ifdef .. `endif
   is strongly recommended instead).
diff --git a/frontends/ilang/ilang_frontend.cc b/frontends/ilang/ilang_frontend.cc
index f3ad3a199..572a35720 100644
--- a/frontends/ilang/ilang_frontend.cc
+++ b/frontends/ilang/ilang_frontend.cc
@@ -32,7 +32,17 @@ void rtlil_frontend_ilang_yyerror(char const *s)
 }
 
 struct IlangFrontend : public Frontend {
-	IlangFrontend() : Frontend("ilang") { }
+	IlangFrontend() : Frontend("ilang", "read modules from ilang file") { }
+	virtual void help()
+	{
+		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
+		log("\n");
+		log("    read_ilang [filename]\n");
+		log("\n");
+		log("Load modules from an ilang file to the current design. (ilang is a text\n");
+		log("representation of a design in yosys's internal format.)\n");
+		log("\n");
+	}
 	virtual void execute(FILE *&f, std::string filename, std::vector<std::string> args, RTLIL::Design *design)
 	{
 		log_header("Executing ILANG frontend.\n");
diff --git a/frontends/verilog/verilog_frontend.cc b/frontends/verilog/verilog_frontend.cc
index e8af13888..878f1c0ec 100644
--- a/frontends/verilog/verilog_frontend.cc
+++ b/frontends/verilog/verilog_frontend.cc
@@ -39,7 +39,52 @@ using namespace VERILOG_FRONTEND;
 // use the Verilog bison/flex parser to generate an AST and use AST::process() to convert it to RTLIL
 
 struct VerilogFrontend : public Frontend {
-	VerilogFrontend() : Frontend("verilog") { }
+	VerilogFrontend() : Frontend("verilog", "read modules from verilog file") { }
+	virtual void help()
+	{
+		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
+		log("\n");
+		log("    read_verilog [filename]\n");
+		log("\n");
+		log("Load modules from a verilog file to the current design. A large subset of\n");
+		log("Verilog-2005 is supported.\n");
+		log("\n");
+		log("    -dump_ast\n");
+		log("        dump abstract syntax tree (after simplification)\n");
+		log("\n");
+		log("    -dump_ast_diff\n");
+		log("        dump ast differences before and after simplification\n");
+		log("\n");
+		log("    -dump_vlog\n");
+		log("        dump ast as verilog code (after simplification)\n");
+		log("\n");
+		log("    -yydebug\n");
+		log("        enable parser debug output\n");
+		log("\n");
+		log("    -nolatches\n");
+		log("        usually latches are synthesized into logic loops\n");
+		log("        this option prohibits this and sets the output to 'x'\n");
+		log("        in what would be the latches hold condition\n");
+		log("\n");
+		log("        this behavior can also be achieved by setting the\n");
+		log("        'nolatches' attribute on the respective module or\n");
+		log("        always block.\n");
+		log("\n");
+		log("    -nomem2reg\n");
+		log("        under certain conditions memories are converted to registers\n");
+		log("        early during simplification to ensure correct handling of\n");
+		log("        complex corner cases. this option disables this behavior.\n");
+		log("\n");
+		log("        this can also be achieved by setting the 'nomem2reg'\n");
+		log("        attribute on the respective module or register.\n");
+		log("\n");
+		log("    -ppdump\n");
+		log("        dump verilog code after pre-processor\n");
+		log("\n");
+		log("    -nopp\n");
+		log("        do not run the pre-processor\n");
+		log("\n");
+	}
 	virtual void execute(FILE *&f, std::string filename, std::vector<std::string> args, RTLIL::Design *design)
 	{
 		bool flag_dump_ast = false;
-- 
2.30.2