[LLVMdev] opt -verify

[Ryan M. Lefever]

I followed what you said and called verifyModule() with the 
AbortProcessAction option.  verifyModule() returns false, but does not 
abort and does not print out any information about what caused the 
verification to fail.

Chris Lattner wrote:
> On Wed, 21 Feb 2007, Ryan M. Lefever wrote:
>> I am writing an interprocedural compiler pass.  Because the passneeds
>> information from a FunctionPass, e.g., the post-dominance frontier
>> (PDF), and because a ModulePass is not permitted to require a
>> FunctionPass, I am forced to make my pass a FunctionPass and do majority
>> of its work in the doFinalization() method.
> 
> ok
> 
>> When I run "opt -mypass -verify -o code2.bc code1.bc" I get no
>> complaints.  However, if I then try run "opt -simplifycfg -verify -o
>> code3.bc code2.bc," I get the assertion failure below.  If thought that
>> the verify option should have made sure that bytecode written to
>> code2.bc was correct.  Am I incorrect?
> 
> Yes.  the passmanager runs the passes in roughly this order:
> 
> 1. doinitialization for mypass and verify
> 2. runOnModule for mypass
> 3. verifier::runOnFunction for each function
> 4. dofinalization for mypass
> 5. dofinalization for verify
> 
> Because you'd doing your xform in #4, but verifier checks the code at #3, 
> you lose :(
> 
> However, there is hope!  Just call "llvm/Analysis/Verifier.h" -> 
> verifyModule or verifyFunction explicitly in your pass.
> 
> -Chris
> 
>> opt: Reader.cpp:1978: llvm::Value*
>> llvm::BytecodeReader::ParseConstantPoolValue(unsigned int): Assertion
>> `(!isa<Constant>(Result) || !cast<Constant>(Result)->isNullValue()) ||
>> !hasImplicitNull(TypeID) && "Cannot read null values from bytecode!"'
>> failed.
>> opt((anonymous namespace)::PrintStackTrace()+0x1a)[0x8645bae]
>> opt((anonymous namespace)::SignalHandler(int)+0x112)[0x8645e74]
>> [0x70f420]
>> /lib/libc.so.6(abort+0x101)[0x4cab64f1]
>> /lib/libc.so.6(__assert_fail+0xfd)[0x4caae859]
>> opt(llvm::BytecodeReader::ParseConstantPoolValue(unsigned
>> int)+0x1b31)[0x856e825]
>> opt(llvm::BytecodeReader::ParseConstantPool(std::vector<llvm::BytecodeReader::ValueList*,
>> std::allocator<llvm::BytecodeReader::ValueList*> >&,
>> std::vector<llvm::PATypeHolder, std::allocator<llvm::PATypeHolder> >&,
>> bool)+0x147)[0x856e985]
>> opt(llvm::BytecodeReader::ParseModule()+0x188)[0x856edfe]
>> opt(llvm::BytecodeReader::ParseBytecode(unsigned char const*, unsigned
>> int, std::basic_string<char, std::char_traits<char>,
>> std::allocator<char> > const&, std::basic_string<char,
>> std::char_traits<char>, std::allocator<char> >*)+0x539)[0x856f6c1]
>> opt((anonymous
>> namespace)::BytecodeFileReader::read(std::basic_string<char,
>> std::char_traits<char>, std::allocator<char> >*)+0xeb)[0x855b569]
>> opt(llvm::getBytecodeModuleProvider(std::basic_string<char,
>> std::char_traits<char>, std::allocator<char> > const&,
>> std::basic_string<char, std::char_traits<char>, std::allocator<char> >*,
>> llvm::BytecodeHandler*)+0x93)[0x855b60b]
>> opt(llvm::ParseBytecodeFile(std::basic_string<char,
>> std::char_traits<char>, std::allocator<char> > const&,
>> std::basic_string<char, std::char_traits<char>, std::allocator<char>
>>> *)+0x20)[0x855b88e]
>> opt(main+0x7e)[0x8378c90]
>> /lib/libc.so.6(__libc_start_main+0xdc)[0x4caa24e4]
>> opt(__gxx_personality_v0+0x149)[0x836bac1]
>> Abort
>>
>> Regards,
>> Ryan
>>
>>
>>
> 
> -Chris
> 

-- 
Ryan M. Lefever  [http://www.ews.uiuc.edu/~lefever]