[flang] [llvm] [mlir][llvm][OpenMP] Hoist __atomic_load alloca (PR #132888)

[via llvm-commits]

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@@ -118,8 +118,14 @@ AtomicInfo::EmitAtomicLoadLibcall(AtomicOrdering AO) {
   Value *PtrVal = getAtomicPointer();
   PtrVal = Builder->CreateAddrSpaceCast(PtrVal, PointerType::getUnqual(Ctx));
   Args.push_back(PtrVal);
+
+  auto CurrentIP = Builder->saveIP();
+  BasicBlock &InsertBB =
+      Builder->GetInsertBlock()->getParent()->getEntryBlock();
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NimishMishra wrote:

Hi @tblah, 

I have enclosed the offending compare-exchange loop with a stack save/restore, and the SEGFAULT is resolved now in my testing.

Do you think we need the stack save/restore for atomic reads too (where we would not have any updates)? I could not reproduce a problem as such, so have not added the save/restore as of now. Do let me know if they are needed for atomic reads too.

https://github.com/llvm/llvm-project/pull/132888