llvm dev - Apr 2019 - How can I use llvm::LoopInfo in the runOnModule method?

Hi all,


I tried to have a LoopInfo object in a function pass, and add addRequired
in getAnalysisUsage, and then use getAnalysis in runOnFunction(). It worked
OK.
Now I want to have a module pass to traverse the functions, and similarly,
I want to have to loop information of the functions.
When I did the above in runOnModule, and build the module pass, the
following error popped out, and the compile did not succeed:

[ 50%] Building CXX object src/CMakeFiles/SkeletonPass.dir/Skeleton.cpp.o
/home/**/Desktop/skeleton/src/Skeleton.cpp: In member function
‘virtual bool llvm::SkeletonPass::runOnModule(llvm::Module&)’:
/home/**/Desktop/skeleton/src/Skeleton.cpp:47:43: error: no matching
function for call to
‘llvm::SkeletonPass::getAnalysis(llvm::Function*&)’
     LoopInfo &LI = getAnalysis<LoopInfo>(F);

...
home/**/Work/llvm-6.0.1.src/include/llvm/PassAnalysisSupport.h: In
instantiation of ‘llvm::AnalysisUsage&
llvm::AnalysisUsage::addRequired() [with PassClass = llvm::LoopInfo]’:
/home/**/Desktop/skeleton/src/Skeleton.cpp:24:38:   required from here
/home/**/Work/llvm-6.0.1.src/include/llvm/PassAnalysisSupport.h:67:39:
error: ‘ID’ is not a member of ‘llvm::LoopInfo’
     return addRequiredID(PassClass::ID);
                                       ^

Here is my source code:

#include "llvm/Pass.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/IR/Dominators.h"
#include "llvm/Analysis/LoopInfo.h"

namespace llvm
{
    class SkeletonPass : public ModulePass
    {
    public:
        static char ID;
        SkeletonPass() : ModulePass(ID) {}
        bool runOnModule(Module &M) override;
        virtual StringRef getPassName() const override
        {
            return "Skeleton";
        }
        virtual void getAnalysisUsage(AnalysisUsage &AU) const override {
            errs() << "get analysis usage method.\n";
            AU.addRequired<LoopInfo>();
        }
    };

    Pass *createSkeletonPass()
    {
        return new SkeletonPass();
    }

    char SkeletonPass::ID = 0;
    Pass *createSkeletonPass();
    void initializeSkeletonPass(PassRegistry &Registry);


} // namespace llvm

using namespace llvm;
using namespace std;


bool SkeletonPass::runOnModule(llvm::Module &M){
    errs() << "=============start=============\n";
    auto F = M.getFunction("main");
    LoopInfo &LI = getAnalysis<LoopInfo>(F);

    LI.print(errs());
    errs() << "==========================\n";
}

static RegisterPass<SkeletonPass> X("run", "Hello world
pass", false, false);

The version of LLVM is 6.0.1, can anyone tell me the correct way to handle
this in a module pass? Thanks a lot!

Best,
Liu
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://lists.llvm.org/pipermail/llvm-dev/attachments/20190402/e5bdc3b5/attachment.html>

It should be `LoopInfoWrapperPass` instead of just `LoopInfo`, but you
can also get the same information if you manually construct a
dominator tree and target info first and pass those to the LoopInfo
constructor.

On Tue, Apr 2, 2019 at 2:48 AM J Skye via llvm-dev
<llvm-dev at lists.llvm.org> wrote:
>
> Hi all,
>
>
> I tried to have a LoopInfo object in a function pass, and add addRequired
in getAnalysisUsage, and then use getAnalysis in runOnFunction(). It worked OK.
> Now I want to have a module pass to traverse the functions, and similarly,
I want to have to loop information of the functions.
> When I did the above in runOnModule, and build the module pass, the
following error popped out, and the compile did not succeed:
>
> [ 50%] Building CXX object src/CMakeFiles/SkeletonPass.dir/Skeleton.cpp.o
> /home/**/Desktop/skeleton/src/Skeleton.cpp: In member function ‘virtual
bool llvm::SkeletonPass::runOnModule(llvm::Module&)’:
> /home/**/Desktop/skeleton/src/Skeleton.cpp:47:43: error: no matching
function for call to ‘llvm::SkeletonPass::getAnalysis(llvm::Function*&)’
>      LoopInfo &LI = getAnalysis<LoopInfo>(F);
>
> ...
> home/**/Work/llvm-6.0.1.src/include/llvm/PassAnalysisSupport.h: In
instantiation of ‘llvm::AnalysisUsage& llvm::AnalysisUsage::addRequired()
[with PassClass = llvm::LoopInfo]’:
> /home/**/Desktop/skeleton/src/Skeleton.cpp:24:38:   required from here
> /home/**/Work/llvm-6.0.1.src/include/llvm/PassAnalysisSupport.h:67:39:
error: ‘ID’ is not a member of ‘llvm::LoopInfo’
>      return addRequiredID(PassClass::ID);
>                                        ^
>
> Here is my source code:
>
> #include "llvm/Pass.h"
> #include "llvm/IR/Function.h"
> #include "llvm/IR/Module.h"
> #include "llvm/Support/raw_ostream.h"
> #include "llvm/IR/Dominators.h"
> #include "llvm/Analysis/LoopInfo.h"
>
> namespace llvm
> {
>     class SkeletonPass : public ModulePass
>     {
>     public:
>         static char ID;
>         SkeletonPass() : ModulePass(ID) {}
>         bool runOnModule(Module &M) override;
>         virtual StringRef getPassName() const override
>         {
>             return "Skeleton";
>         }
>         virtual void getAnalysisUsage(AnalysisUsage &AU) const override
{
>             errs() << "get analysis usage method.\n";
>             AU.addRequired<LoopInfo>();
>         }
>     };
>
>     Pass *createSkeletonPass()
>     {
>         return new SkeletonPass();
>     }
>
>     char SkeletonPass::ID = 0;
>     Pass *createSkeletonPass();
>     void initializeSkeletonPass(PassRegistry &Registry);
>
>
> } // namespace llvm
>
> using namespace llvm;
> using namespace std;
>
>
> bool SkeletonPass::runOnModule(llvm::Module &M){
>     errs() << "=============start=============\n";
>     auto F = M.getFunction("main");
>     LoopInfo &LI = getAnalysis<LoopInfo>(F);
>
>     LI.print(errs());
>     errs() << "==========================\n";
> }
>
> static RegisterPass<SkeletonPass> X("run", "Hello
world pass", false, false);
>
> The version of LLVM is 6.0.1, can anyone tell me the correct way to handle
this in a module pass? Thanks a lot!
>
> Best,
> Liu
>
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev

Interesting that we're getting a relative flood of these recently.

See here:

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

I don't think one can reliably get a Function analysis pass from within
a ModulePass using the legacy pass manager.  You have to manually
construct the pass yourself.

                    -David

Jonathan Smith via llvm-dev <llvm-dev at lists.llvm.org> writes:
> It should be `LoopInfoWrapperPass` instead of just `LoopInfo`, but you
> can also get the same information if you manually construct a
> dominator tree and target info first and pass those to the LoopInfo
> constructor.
>
> On Tue, Apr 2, 2019 at 2:48 AM J Skye via llvm-dev
> <llvm-dev at lists.llvm.org> wrote:
>>
>> Hi all,
>>
>>
>> I tried to have a LoopInfo object in a function pass, and add
addRequired in getAnalysisUsage, and then use getAnalysis in runOnFunction(). It
worked OK.
>> Now I want to have a module pass to traverse the functions, and
similarly, I want to have to loop information of the functions.
>> When I did the above in runOnModule, and build the module pass, the
following error popped out, and the compile did not succeed:
>>
>> [ 50%] Building CXX object
src/CMakeFiles/SkeletonPass.dir/Skeleton.cpp.o
>> /home/**/Desktop/skeleton/src/Skeleton.cpp: In member function ‘virtual
bool llvm::SkeletonPass::runOnModule(llvm::Module&)’:
>> /home/**/Desktop/skeleton/src/Skeleton.cpp:47:43: error: no matching
function for call to ‘llvm::SkeletonPass::getAnalysis(llvm::Function*&)’
>>      LoopInfo &LI = getAnalysis<LoopInfo>(F);
>>
>> ...
>> home/**/Work/llvm-6.0.1.src/include/llvm/PassAnalysisSupport.h: In
instantiation of ‘llvm::AnalysisUsage& llvm::AnalysisUsage::addRequired()
[with PassClass = llvm::LoopInfo]’:
>> /home/**/Desktop/skeleton/src/Skeleton.cpp:24:38:   required from here
>> /home/**/Work/llvm-6.0.1.src/include/llvm/PassAnalysisSupport.h:67:39:
error: ‘ID’ is not a member of ‘llvm::LoopInfo’
>>      return addRequiredID(PassClass::ID);
>>                                        ^
>>
>> Here is my source code:
>>
>> #include "llvm/Pass.h"
>> #include "llvm/IR/Function.h"
>> #include "llvm/IR/Module.h"
>> #include "llvm/Support/raw_ostream.h"
>> #include "llvm/IR/Dominators.h"
>> #include "llvm/Analysis/LoopInfo.h"
>>
>> namespace llvm
>> {
>>     class SkeletonPass : public ModulePass
>>     {
>>     public:
>>         static char ID;
>>         SkeletonPass() : ModulePass(ID) {}
>>         bool runOnModule(Module &M) override;
>>         virtual StringRef getPassName() const override
>>         {
>>             return "Skeleton";
>>         }
>>         virtual void getAnalysisUsage(AnalysisUsage &AU) const
override {
>>             errs() << "get analysis usage method.\n";
>>             AU.addRequired<LoopInfo>();
>>         }
>>     };
>>
>>     Pass *createSkeletonPass()
>>     {
>>         return new SkeletonPass();
>>     }
>>
>>     char SkeletonPass::ID = 0;
>>     Pass *createSkeletonPass();
>>     void initializeSkeletonPass(PassRegistry &Registry);
>>
>>
>> } // namespace llvm
>>
>> using namespace llvm;
>> using namespace std;
>>
>>
>> bool SkeletonPass::runOnModule(llvm::Module &M){
>>     errs() << "=============start=============\n";
>>     auto F = M.getFunction("main");
>>     LoopInfo &LI = getAnalysis<LoopInfo>(F);
>>
>>     LI.print(errs());
>>     errs() << "==========================\n";
>> }
>>
>> static RegisterPass<SkeletonPass> X("run", "Hello
world pass", false, false);
>>
>> The version of LLVM is 6.0.1, can anyone tell me the correct way to
handle this in a module pass? Thanks a lot!
>>
>> Best,
>> Liu
>>
>> _______________________________________________
>> 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