llvm dev - Mar 2019 - Unable to find requested analysis info (Interesting Assertion Failture for Specific Target Source Code)

Dear all,

    Hi! I encounter an interesting assertion failure when implementing my Pass,
which is defined with the member functions shown below:
======================My Pass=====================================bool
MYPass::runOnModule(Module &M)
{
    for (auto &F : M)
        {
            SE = &getAnalysis<ScalarEvolutionWrapperPass>(F).getSE();
            ......
        }
    }
    return false;
}

void MYPass::getAnalysisUsage(AnalysisUsage &AU) const
{
    AU.setPreservesAll();
    AU.addRequired<LoopInfoWrapperPass>();
    AU.addRequired<ScalarEvolutionWrapperPass>();
    AU.addRequired<LoopAccessLegacyAnalysis>();
    AU.addRequired<DominatorTreeWrapperPass>();
    AU.addRequired<OptimizationRemarkEmitterWrapperPass>();
}
==================================================================
    Then, I got the assert failure when running the pass on the following code
======================Target Code with Assertion
Failure=============================void f ( int A[50][100]) {
  int N = 100;
  int M = 50;
  int B[50][100];
  for ( int j = 0; j < N; j++ )
    for ( int i = 0; i < M; i++ )
      B[i][j]=i;
  for ( int j = 1; j < N; j++ )
    for ( int i = 1; i < M; i++ )
      A[i][j] = i%2? A[i-1][j]:B[i][j];
  return;
}
=====================================================================    The
thing made this failture interesting is that I got no failure when running the
pass on the other code, e.g.
===========================Target Code without Assertion
Failure====================================void f ( int A[50][100],int
B[50][100]) {
  int N = 100;
  int M = 50;
  for ( int j = 0; j < N; j++ )
    for ( int i = 0; i < M; i++ )
      B[i][j]=i;
  for ( int j = 1; j < N; j++ )
    for ( int i = 1; i < M; i++ )
      A[i][j] = i%2? A[i-1][j]:B[i][j];
  return;
}

    I am confused by this situation because this failure has not occurred before
and it shoud not be effected by the target code.
    Thanks in advance for your time and suggestion!!!^_^

Best regards,
------------------------------------------
Tingyuan LIANG
MPhil Student
Department of Electronic and Computer Engineering
The Hong Kong University of Science and Technology

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Dear all,

    Hi! I encounter an interesting assertion failure: (sorry for re-sending the
email because I need to add the details of the assertion)

        /usr/local/include/llvm/PassAnalysisSupport.h:262: AnalysisType&
llvm::Pass::getAnalysisID(llvm::AnalysisID, llvm::Function&) [with
AnalysisType = llvm::ScalarEvolutionWrapperPass; llvm::AnalysisID = const
void*]: Assertion `ResultPass && "Unable to find requested analysis
info"' failed

    when implementing my Pass, which is defined with the member functions shown
below:
======================My Pass=====================================bool
MYPass::runOnModule(Module &M)
{
    for (auto &F : M)
        {
            SE = &getAnalysis<ScalarEvolutionWrapperPass>(F).getSE();
            ......
        }
    }
    return false;
}

void MYPass::getAnalysisUsage(AnalysisUsage &AU) const
{
    AU.setPreservesAll();
    AU.addRequired<LoopInfoWrapperPass>();
    AU.addRequired<ScalarEvolutionWrapperPass>();
    AU.addRequired<LoopAccessLegacyAnalysis>();
    AU.addRequired<DominatorTreeWrapperPass>();
    AU.addRequired<OptimizationRemarkEmitterWrapperPass>();
}
==================================================================
    Then, I got the assert failure when running the pass on the following code
======================Target Code with Assertion
Failure=============================void f ( int A[50][100]) {
  int N = 100;
  int M = 50;
  int B[50][100];
  for ( int j = 0; j < N; j++ )
    for ( int i = 0; i < M; i++ )
      B[i][j]=i;
  for ( int j = 1; j < N; j++ )
    for ( int i = 1; i < M; i++ )
      A[i][j] = i%2? A[i-1][j]:B[i][j];
  return;
}
=====================================================================    The
thing made this failture interesting is that I got no failure when running the
pass on the other code, e.g.
===========================Target Code without Assertion
Failure====================================void f ( int A[50][100],int
B[50][100]) {
  int N = 100;
  int M = 50;
  for ( int j = 0; j < N; j++ )
    for ( int i = 0; i < M; i++ )
      B[i][j]=i;
  for ( int j = 1; j < N; j++ )
    for ( int i = 1; i < M; i++ )
      A[i][j] = i%2? A[i-1][j]:B[i][j];
  return;
}

    I am confused by this situation because this failure has not occurred before
and it shoud not be effected by the target code.
    Thanks in advance for your time and suggestion!!!^_^

Best regards,
------------------------------------------
Tingyuan LIANG
MPhil Student
Department of Electronic and Computer Engineering
The Hong Kong University of Science and Technology

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See this:

http://lists.llvm.org/pipermail/llvm-dev/2019-March/131346.html

I have also had trouble with function-level analysis passes used by a
ModulePass.  It seems like the legacy pass manager simply doesn't
support it.  It works fine with the new pass manager.

What's scary is that the code compiles just fine but it fails at runtime
(for some codes, as you've observed) because the legacy pass manager
deletes each function analysis pass sometime after getAnalysis is run.

The on-the-fly pass manager systems seems fundamentally broken to me,
though I haven't got any responses on that post that either confirm or
deny that.

                     -David

Tingyuan LIANG via llvm-dev <llvm-dev at lists.llvm.org> writes:
> Dear all,
>
>     Hi! I encounter an interesting assertion failure: (sorry for re-sending
the email because I need to add the details of the assertion)
>
>         /usr/local/include/llvm/PassAnalysisSupport.h:262:
AnalysisType& llvm::Pass::getAnalysisID(llvm::AnalysisID,
llvm::Function&) [with AnalysisType > llvm::ScalarEvolutionWrapperPass;
llvm::AnalysisID = const void*]: Assertion `ResultPass && "Unable
to find requested analysis info"' failed
>
>     when implementing my Pass, which is defined with the member functions
shown below:
> ======================My Pass=====================================> bool
MYPass::runOnModule(Module &M)
> {
>     for (auto &F : M)
>         {
>             SE =
&getAnalysis<ScalarEvolutionWrapperPass>(F).getSE();
>             ......
>         }
>     }
>     return false;
> }
>
> void MYPass::getAnalysisUsage(AnalysisUsage &AU) const
> {
>     AU.setPreservesAll();
>     AU.addRequired<LoopInfoWrapperPass>();
>     AU.addRequired<ScalarEvolutionWrapperPass>();
>     AU.addRequired<LoopAccessLegacyAnalysis>();
>     AU.addRequired<DominatorTreeWrapperPass>();
>     AU.addRequired<OptimizationRemarkEmitterWrapperPass>();   
> }
> ==================================================================>
>     Then, I got the assert failure when running the pass on the following
code
> ======================Target Code with Assertion
Failure=============================> void f ( int A[50][100]) {
>   int N = 100;
>   int M = 50;
>   int B[50][100];
>   for ( int j = 0; j < N; j++ )
>     for ( int i = 0; i < M; i++ )
>       B[i][j]=i;
>   for ( int j = 1; j < N; j++ )
>     for ( int i = 1; i < M; i++ )
>       A[i][j] = i%2? A[i-1][j]:B[i][j];
>   return;
> }
> =====================================================================>  
The thing made this failture interesting is that I got no failure when running
the pass on the other code, e.g.
> ===========================Target Code without Assertion
Failure====================================> void f ( int A[50][100],int
B[50][100]) {
>   int N = 100;
>   int M = 50;
>   for ( int j = 0; j < N; j++ )
>     for ( int i = 0; i < M; i++ )
>       B[i][j]=i;
>   for ( int j = 1; j < N; j++ )
>     for ( int i = 1; i < M; i++ )
>       A[i][j] = i%2? A[i-1][j]:B[i][j];
>   return;
> }
>
>     I am confused by this situation because this failure has not occurred
before and it shoud not be effected by the target code.
>     Thanks in advance for your time and suggestion!!!^_^
>
> Best regards,
> ------------------------------------------
> Tingyuan LIANG
> MPhil Student
> Department of Electronic and Computer Engineering
> The Hong Kong University of Science and Technology
>
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
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