Mikhail Gudim via llvm-dev
2020-Jan-07 13:13 UTC
[llvm-dev] Let CallGraphSCCPass Use Function-Level Analysis
Dear all, I would like to use the PostDominatorTree in ArgPromotion. I did not find an example of how to use function level analysis inside CallGraphSCCPass. I tried to follow an example of how to use function-level pass in a module pass, but I hit "llvm_unreachable" in PMDataManager::addLowerLevelRequiredPass. What would be a proper way to make PostDominatorTree available in ArgPromotion? Thanks in advance, Mikhail -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20200107/dd1bc481/attachment.html>
Brian Gesiak via llvm-dev
2020-Jan-07 16:55 UTC
[llvm-dev] Let CallGraphSCCPass Use Function-Level Analysis
Hello! The new pass manager provides analysis proxies from one IR unit
type to another. These are specializations of
'llvm::InnerAnalysisManagerProxy'. For example,
'llvm::FunctionAnalysisManagerModuleProxy' allows you to access
function analyses from within module passes.
In your case, it sounds like you'd want to use
'llvm::FunctionAnalysisManagerCGSCCProxy', which allows you to access
function analyses from within an CGSCC pass. Here's an example of
using it:
```
class MyCGSCCPass : public llvm::PassInfoMixin<MyCGSCCPass> {
public:
llvm::PreservedAnalyses run(llvm::LazyCallGraph::SCC &C,
llvm::CGSCCAnalysisManager &AM,
llvm::LazyCallGraph &CG,
llvm::CGSCCUpdateResult &UR) {
llvm::FunctionAnalysisManager &FAM
AM.getResult<llvm::FunctionAnalysisManagerCGSCCProxy>(C, CG)
.getManager();
for (llvm::LazyCallGraph::Node &N : C) {
llvm::Function &F = N.getFunction();
llvm::PostDominatorTree &PDT
FAM.getResult<llvm::PostDominatorTreeAnalysis>(F);
PDT.print(llvm::outs());
}
return llvm::PreservedAnalyses::none();
}
};
```
Here's a full example of the above:
https://gist.github.com/modocache/d5804ba567476e32cad1fd0850363532
I was just reading through this part of the codebase, so I'm a little
familiar with it now. Anyway, hope this helps!
- Brian Gesiak
On Tue, Jan 7, 2020 at 8:13 AM Mikhail Gudim via llvm-dev
<llvm-dev at lists.llvm.org> wrote:>
> Dear all,
>
>
>
> I would like to use the PostDominatorTree in ArgPromotion. I did not find
an example of how to use function level analysis inside CallGraphSCCPass. I
tried to follow an example of how to use function-level pass in a module pass,
but I hit “llvm_unreachable” in PMDataManager::addLowerLevelRequiredPass.
>
>
>
> What would be a proper way to make PostDominatorTree available in
ArgPromotion?
>
>
>
> Thanks in advance,
>
>
>
> Mikhail
>
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
Doerfert, Johannes via llvm-dev
2020-Jan-07 17:18 UTC
[llvm-dev] Let CallGraphSCCPass Use Function-Level Analysis
Hi Mikhail, As Brian noted, stuff like this works better in the new pass manager. Even in the old pass manager I thought it should work though. Did you initialize the pass, via `INITIALIZE_PASS_DEPENDENCY(PostDominatorTreeWrapperPass)`? Did you require it, via ` AU.addRequired<PostDominatorTreeWrapperPass>();`? Btw. May I ask what you are planning to do? Cheers, Johannes On 01/07, Brian Gesiak via llvm-dev wrote:> Hello! The new pass manager provides analysis proxies from one IR unit > type to another. These are specializations of > 'llvm::InnerAnalysisManagerProxy'. For example, > 'llvm::FunctionAnalysisManagerModuleProxy' allows you to access > function analyses from within module passes. > > In your case, it sounds like you'd want to use > 'llvm::FunctionAnalysisManagerCGSCCProxy', which allows you to access > function analyses from within an CGSCC pass. Here's an example of > using it: > > ``` > class MyCGSCCPass : public llvm::PassInfoMixin<MyCGSCCPass> { > public: > llvm::PreservedAnalyses run(llvm::LazyCallGraph::SCC &C, > llvm::CGSCCAnalysisManager &AM, > llvm::LazyCallGraph &CG, > llvm::CGSCCUpdateResult &UR) { > llvm::FunctionAnalysisManager &FAM > AM.getResult<llvm::FunctionAnalysisManagerCGSCCProxy>(C, CG) > .getManager(); > for (llvm::LazyCallGraph::Node &N : C) { > llvm::Function &F = N.getFunction(); > llvm::PostDominatorTree &PDT > FAM.getResult<llvm::PostDominatorTreeAnalysis>(F); > PDT.print(llvm::outs()); > } > return llvm::PreservedAnalyses::none(); > } > }; > ``` > > Here's a full example of the above: > https://gist.github.com/modocache/d5804ba567476e32cad1fd0850363532 > > I was just reading through this part of the codebase, so I'm a little > familiar with it now. Anyway, hope this helps! > > - Brian Gesiak > > On Tue, Jan 7, 2020 at 8:13 AM Mikhail Gudim via llvm-dev > <llvm-dev at lists.llvm.org> wrote: > > > > Dear all, > > > > > > > > I would like to use the PostDominatorTree in ArgPromotion. I did not find an example of how to use function level analysis inside CallGraphSCCPass. I tried to follow an example of how to use function-level pass in a module pass, but I hit “llvm_unreachable” in PMDataManager::addLowerLevelRequiredPass. > > > > > > > > What would be a proper way to make PostDominatorTree available in ArgPromotion? > > > > > > > > Thanks in advance, > > > > > > > > Mikhail > > > > _______________________________________________ > > LLVM Developers mailing list > > llvm-dev at lists.llvm.org > > https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev > _______________________________________________ > LLVM Developers mailing list > llvm-dev at lists.llvm.org > https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev-- Johannes Doerfert Researcher Argonne National Laboratory Lemont, IL 60439, USA jdoerfert at anl.gov -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 228 bytes Desc: not available URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20200107/90203561/attachment.sig>