Updated the liberty parser to accept [A:B] ranges (AST has not been updated). Liberty parser now also accepts key : value pair lines that do not end in ';'.

2 files changed, 90 insertions, 7 deletions

diff --git a/passes/techmap/libparse.cc b/passes/techmap/libparse.cc
index 3927a657b..878ca3160 100644
--- a/passes/techmap/libparse.cc
+++ b/passes/techmap/libparse.cc
@@ -24,6 +24,7 @@
 #include <istream>
 #include <fstream>
 #include <iostream>
+#include <sstream>
 
 #ifndef FILTERLIB
 #include "kernel/log.h"
@@ -86,15 +87,17 @@ int LibertyParser::lexer(std::string &str)
 {
 	int c;
 
+    // eat whitespace
 	do {
 		c = f.get();
 	} while (c == ' ' || c == '\t' || c == '\r');
 
-	if (('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') || ('0' <= c && c <= '9') || c == '_' || c == '-' || c == '+' || c == '.' || c == '[' || c == ']') {
+    // search for identifiers, numbers, plus or minus.
+	if (('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') || ('0' <= c && c <= '9') || c == '_' || c == '-' || c == '+' || c == '.') {
 		str = c;
 		while (1) {
 			c = f.get();
-			if (('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') || ('0' <= c && c <= '9') || c == '_' || c == '-' || c == '+' || c == '.' || c == '[' || c == ']')
+			if (('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') || ('0' <= c && c <= '9') || c == '_' || c == '-' || c == '+' || c == '.')
 				str += c;
 			else
 				break;
@@ -111,6 +114,8 @@ int LibertyParser::lexer(std::string &str)
 		}
 	}
 
+    // if it wasn't an identifer, number of array range,
+    // maybe it's a string?
 	if (c == '"') {
 		str = "";
 		while (1) {
@@ -125,9 +130,10 @@ int LibertyParser::lexer(std::string &str)
 		return 'v';
 	}
 
+    // if it wasn't a string, perhaps it's a comment or a forward slash?
 	if (c == '/') {
 		c = f.get();
-		if (c == '*') {
+		if (c == '*') {         // start of '/*' block comment
 			int last_c = 0;
 			while (c > 0 && (last_c != '*' || c != '/')) {
 				last_c = c;
@@ -136,7 +142,7 @@ int LibertyParser::lexer(std::string &str)
 					line++;
 			}
 			return lexer(str);
-		} else if (c == '/') {
+		} else if (c == '/') {  // start of '//' line comment
 			while (c > 0 && c != '\n')
 				c = f.get();
 			line++;
@@ -144,9 +150,10 @@ int LibertyParser::lexer(std::string &str)
 		}
 		f.unget();
 		// fprintf(stderr, "LEX: char >>/<<\n");
-		return '/';
+		return '/';             // a single '/' charater.
 	}
 
+    // check for a backslash
 	if (c == '\\') {
 		c = f.get();
 		if (c == '\r')
@@ -157,11 +164,15 @@ int LibertyParser::lexer(std::string &str)
 		return '\\';
 	}
 
+    // check for a new line
 	if (c == '\n') {
 		line++;
 		return 'n';
 	}
 
+    // anything else, such as ';' will get passed
+    // through as literal items.
+
 	// if (c >= 32 && c < 255)
 	// 	fprintf(stderr, "LEX: char >>%c<<\n", c);
 	// else
@@ -210,7 +221,12 @@ LibertyAst *LibertyParser::parse()
 				ast->value += str;
 				tok = lexer(str);
 			}
-			if (tok == ';')
+            
+            // In a liberty file, all key : value pairs should end in ';'
+            // However, there are some liberty files in the wild that
+            // just have a newline. We'll be kind and accept a newline
+            // instead of the ';' too..
+			if ((tok == ';') || (tok == 'n'))
 				break;
 			else
 				error();
@@ -225,6 +241,48 @@ LibertyAst *LibertyParser::parse()
 					continue;
 				if (tok == ')')
 					break;
+                
+                // FIXME: the AST needs to be extended to store
+                //        these vector ranges.
+                if (tok == '[')
+                {
+                    // parse vector range [A] or [A:B]
+                    std::string arg;
+                    tok = lexer(arg);
+                    if (tok != 'v')
+                    {
+                        // expected a vector array index
+                        error("Expected a number.");
+                    }
+                    else
+                    {
+                        // fixme: check for number A
+                    }
+                    tok = lexer(arg);
+                    // optionally check for : in case of [A:B]
+                    // if it isn't we just expect ']'
+                    // as we have [A]
+                    if (tok == ':')
+                    {
+                        tok = lexer(arg);
+                        if (tok != 'v')
+                        {
+                            // expected a vector array index
+                            error("Expected a number.");
+                        }
+                        else
+                        {
+                            // fixme: check for number B
+                            tok = lexer(arg);                            
+                        }
+                    }
+                    // expect a closing bracket of array range
+                    if (tok != ']')
+                    {
+                        error("Expected ']' on array range.");
+                    }
+                    continue;           
+                }
 				if (tok != 'v')
 					error();
 				ast->args.push_back(arg);
@@ -255,6 +313,14 @@ void LibertyParser::error()
 	log_error("Syntax error in liberty file on line %d.\n", line);
 }
 
+void LibertyParser::error(const std::string &str)
+{
+    std::stringstream ss;
+    ss << "Syntax error in liberty file on line " << line << ".\n";
+    ss << "  " << str << "\n";
+    log_error("%s", ss.str().c_str());
+}
+
 #else
 
 void LibertyParser::error()
@@ -263,6 +329,15 @@ void LibertyParser::error()
 	exit(1);
 }
 
+void LibertyParser::error(const std::string &str)
+{
+    std::stringstream ss;
+    ss << "Syntax error in liberty file on line " << line << ".\n";
+    ss << "  " << str << "\n";
+    printf("%s", ss.str().c_str());
+    exit(1);
+}
+
 /**** BEGIN: http://svn.clifford.at/tools/trunk/examples/check.h ****/
 
 #define CHECK_NV(result, check)                                      \
diff --git a/passes/techmap/libparse.h b/passes/techmap/libparse.h
index cf6325570..c9ebd06c5 100644
--- a/passes/techmap/libparse.h
+++ b/passes/techmap/libparse.h
@@ -46,9 +46,17 @@ namespace Yosys
 		LibertyAst *ast;
 		LibertyParser(std::istream &f) : f(f), line(1), ast(parse()) {}
 		~LibertyParser() { if (ast) delete ast; }
+        
+        /* lexer return values:
+           'v': identifier, string, array range [...] -> str holds the token string
+           'n': newline
+           anything else is a single character.
+        */
 		int lexer(std::string &str);
-		LibertyAst *parse();
+		
+        LibertyAst *parse();
 		void error();
+        void error(const std::string &str);
 	};
 }