[PATCH] D17157: Add the beginnings of an update API for preserving MemorySSA

[Mikael Holmén via llvm-commits]

Hi,

On 03/02/2016 04:40 PM, Daniel Berlin wrote:
> I'm kinda surprised nothing asserts here, even in debug mode.

Yes, only reason I saw this is because in my out-of-tree backend we do 
some more things in DataLayout::getTypeStoreSize (accessing members in 
the DL object) which caused a SEGV since the DL object was broken.

> But I'll fix if George's fixes didn't do it already.

Yep, I saw the fix now.

Thanks!
Mikael

>
>
> On Wed, Mar 2, 2016 at 2:44 AM, Mikael Holmén
> <mikael.holmen at ericsson.com <mailto:mikael.holmen at ericsson.com>> wrote:
>
>     Hi,
>
>     There seems to be a problem in the MemorySSA.cpp test case:
>
>     First a Function is built
>
>        std::unique_ptr<Function> F(Function::Create(
>            FunctionType::get(B.getVoidTy(), {B.getInt8PtrTy()}, false),
>            GlobalValue::ExternalLinkage, "F"));
>
>     Note that we don't pass any Module to the Function:
>
>        static Function *Create(FunctionType *Ty, LinkageTypes Linkage,
>                                const Twine &N = "", Module *M = nullptr)
>
>     o the Function's Module will be nullptr.
>
>     However, throughout the code there are places where it is assumed
>     that the Module can be fetched, e.g. in
>
>     MemoryLocation MemoryLocation::get(const LoadInst *LI) {
>        AAMDNodes AATags;
>        LI->getAAMetadata(AATags);
>        const auto &DL = LI->getModule()->getDataLayout();
>
>        return MemoryLocation(LI->getPointerOperand(),
>                              DL.getTypeStoreSize(LI->getType()), AATags);
>     }
>
>     which in the MemorySSA test indeed gets called:
>
>     #3  0x00000000006b3886 in llvm::MemoryLocation::get (Inst=0xda03f8)
>     at include/llvm/Analysis/MemoryLocation.h:72
>     #4  0x00000000006b2c84 in
>     llvm::CachingMemorySSAWalker::getClobberingMemoryAccess
>     (this=0xda1bf0, I=0xda03f8)
>          at lib/Transforms/Utils/MemorySSA.cpp:1047
>     #5  0x00000000006aff7a in llvm::MemorySSA::buildMemorySSA
>     (this=0xda0440, AA=0xda16c0, DT=0xda04c0)
>          at lib/Transforms/Utils/MemorySSA.cpp:346
>     #6  0x000000000042786f in
>     MemorySSA_RemoveMemoryAccess_Test::TestBody (this=0xd9a920) at
>     unittests/Transforms/Utils/MemorySSA.cpp:55
>
>     So I suppose a Module should be created as well to setup the test
>     properly.
>
>     Regards,
>     Mikael
>
>
>
>     On 03/01/2016 07:51 PM, Phabricator via llvm-commits wrote:
>
>         This revision was automatically updated to reflect the committed
>         changes.
>         Closed by commit rL262362: Add the beginnings of an update API
>         for preserving MemorySSA (authored by dannyb).
>
>         Changed prior to commit:
>         http://reviews.llvm.org/D17157?vs=47855&id=49511#toc
>
>         Repository:
>             rL LLVM
>
>         http://reviews.llvm.org/D17157
>
>         Files:
>             llvm/trunk/include/llvm/Transforms/Utils/MemorySSA.h
>             llvm/trunk/lib/Transforms/Utils/MemorySSA.cpp
>             llvm/trunk/unittests/Transforms/Utils/CMakeLists.txt
>             llvm/trunk/unittests/Transforms/Utils/MemorySSA.cpp
>
>
>
>         _______________________________________________
>         llvm-commits mailing list
>         llvm-commits at lists.llvm.org <mailto:llvm-commits at lists.llvm.org>
>         http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits
>
>