asmparser doesn't report errors it finds

[lattner]

Bugzilla Link	886
Resolution	FIXED
Resolved on	Feb 22, 2010 12:54
Version	trunk
OS	All
Blocks	llvm/llvm-bugzilla-archive#895

Extended Description

This .ll file is buggy (%X isn't defined):

ulong %foo(ulong %x) { 
         %tmp.1 = load long* %X          ; [#uses=1]
        %tmp.3 = cast long %tmp.1 to ubyte              ; [#uses=1]
        %tmp.4 = shl ulong %x, ubyte %tmp.3             ; [#uses=1]
        ret ulong %tmp.4
}

When parsing it, I don't get a good error from the asmparser, I get assertion failures.

I could have sworn this used to be caught.

-Chris

[lattner]

Reid, please look into this. This is a really annoying regression from your "remove EH" patch.

You'll notice that running on this .ll file causes the parser to call GenerateError. However, it doesn't print
an error, and it returns the bogus module as though success happened.

-Chris

[llvmbot]

I ran the test case. The error is produced in this production:

Module : FunctionList {
$$ = ParserResult = $1;
CurModule.ModuleDone();
CHECK_FOR_ERROR;
};

When ModuleDone() is finished, the TriggerError flag is true and CHECK_FOR_ERROR
invokes YYERROR. This causes yyparse to return 1. Unfortunately, the RunParser
function was invoking yyparse like this:

yyparse();
if (!ParserResult)
return 0;

This doesn't check for the non-zero result from yyparse because it expects
either an exception or a zero-valued ParserResult to indicate the error. To
correct the problem, this code was changed to:

// Check to make sure the parser succeeded
if (yyparse()) {
if (ParserResult)
delete ParserResult;
return 0;
}

// Check to make sure that parsing produced a result
if (!ParserResult)
return 0;

Which checks both error conditions and returns 0 on them both. This fixes the
problem.

[lattner]

Nice.  Does it also print out the error message with that patch?

[llvmbot]

Yes, the error message is printed correctly. It never hits the validator.

[lattner]

perfect

[llvmbot]

Resolved, patch here:

http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20061009/038418.html

[nlewycky]

mentioned in issue llvm/llvm-bugzilla-archive#895

[nlewycky]

mentioned in issue llvm/llvm-bugzilla-archive#895