For PR797:

Rid the Assembly Parser of exceptions. This is a really gross hack but it
will do until the Assembly Parser is re-written as a recursive descent.
The basic premise is that wherever the old "ThrowException" function was
called (new name: GenerateError) we set a flag (TriggerError). Every
production checks that flag and calls YYERROR if it is set. Additionally,
each call to ThrowException in the grammar is replaced with GEN_ERROR
which calls GenerateError and then YYERROR immediately. This prevents
the remaining production from continuing after an error condition.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29763 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 37 insertions, 19 deletions

diff --git a/include/llvm/Assembly/Parser.h b/include/llvm/Assembly/Parser.h
index 39a622b286..bc7995eb6f 100644
--- a/include/llvm/Assembly/Parser.h
+++ b/include/llvm/Assembly/Parser.h
@@ -19,30 +19,45 @@
 namespace llvm {
 
 class Module;
-class ParseException;
-
-
-// The useful interface defined by this file... Parse an ascii file, and return
-// the internal representation in a nice slice'n'dice'able representation.  Note
-// that this does not verify that the generated LLVM is valid, so you should run
-// the verifier after parsing the file to check that it's ok.
-//
-Module *ParseAssemblyFile(const std::string &Filename);// throw (ParseException)
-Module *ParseAssemblyString(const char * AsmString, Module * M);// throw (ParseException)
+class ParseError;
+
+
+/// This function is the main interface to the LLVM Assembly Parse. It parses 
+/// an ascii file that (presumably) contains LLVM Assembly code. It returns a
+/// Module (intermediate representation) with the corresponding features. Note
+/// that this does not verify that the generated Module is valid, so you should
+/// run the verifier after parsing the file to check that it is okay.
+/// @brief Parse LLVM Assembly from a file
+Module *ParseAssemblyFile(
+  const std::string &Filename, ///< The name of the file to parse
+  ParseError* Error = 0        ///< If not null, an object to return errors in.
+);
+
+/// The function is a secondary interface to the LLVM Assembly Parse. It parses 
+/// an ascii string that (presumably) contains LLVM Assembly code. It returns a
+/// Module (intermediate representation) with the corresponding features. Note
+/// that this does not verify that the generated Module is valid, so you should
+/// run the verifier after parsing the file to check that it is okay.
+/// @brief Parse LLVM Assembly from a string
+Module *ParseAssemblyString(
+  const char * AsmString, ///< The string containing assembly
+  Module * M,             ///< A module to add the assembly too.
+  ParseError* Error = 0   ///< If not null, an object to return errors in.
+);
 
 //===------------------------------------------------------------------------===
 //                              Helper Classes
 //===------------------------------------------------------------------------===
 
-// ParseException - For when an exceptional event is generated by the parser.
-// This class lets you print out the exception message
-//
-class ParseException {
+/// An instance of this class can be passed to ParseAssemblyFile or 
+/// ParseAssemblyString functions in order to capture error information from
+/// the parser.  It provides a standard way to print out the error message
+/// including the file name and line number where the error occurred.
+/// @brief An LLVM Assembly Parsing Error Object
+class ParseError {
 public:
-  ParseException(const std::string &filename, const std::string &message,
-                 int LineNo = -1, int ColNo = -1);
-
-  ParseException(const ParseException &E);
+  ParseError() : Filename("unknown"), Message("none"), LineNo(0), ColumnNo(0) {}
+  ParseError(const ParseError &E);
 
   // getMessage - Return the message passed in at construction time plus extra
   // information extracted from the options used to parse with...
@@ -57,6 +72,9 @@ public:
     return Filename;
   }
 
+  void setError(const std::string &filename, const std::string &message,
+                 int LineNo = -1, int ColNo = -1);
+
   // getErrorLocation - Return the line and column number of the error in the
   // input source file.  The source filename can be derived from the
   // ParserOptions in effect.  If positional information is not applicable,
@@ -71,7 +89,7 @@ private :
   std::string Message;
   int LineNo, ColumnNo;                               // -1 if not relevant
 
-  ParseException &operator=(const ParseException &E); // objects by reference
+  ParseError &operator=(const ParseError &E); // objects by reference
 };
 
 } // End llvm namespace