[OpenMP][OMPIRBuilder] Fix missing alloca address space from downstream

Downstream we appear to have cut a corner when it comes to alloca address spaces in the
createFakeIntVal function, rather than create the alloca in the right address space and
then cast it appropriately, we forced it into the default address space which is invalid
for AMDGPU and now that we're stricter verifying this it was causing failed tests.

Author: agozillon

llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp

@@ -394,20 +394,28 @@ BasicBlock *llvm::splitBBWithSuffix(IRBuilderBase &Builder, bool CreateBranch,
 // This function creates a fake integer value and a fake use for the integer
 // value. It returns the fake value created. This is useful in modeling the
 // extra arguments to the outlined functions.
-Value *createFakeIntVal(IRBuilderBase &Builder,
+Value *createFakeIntVal(IRBuilderBase &Builder, Module &M,
                         OpenMPIRBuilder::InsertPointTy OuterAllocaIP,
                         llvm::SmallVectorImpl<Instruction *> &ToBeDeleted,
                         OpenMPIRBuilder::InsertPointTy InnerAllocaIP,
                         const Twine &Name = "", bool AsPtr = true) {
   Builder.restoreIP(OuterAllocaIP);
   Instruction *FakeVal;
   AllocaInst *FakeValAddr =
-      Builder.CreateAlloca(Builder.getInt32Ty(), 0, nullptr, Name + ".addr");
+      Builder.CreateAlloca(Builder.getInt32Ty(), nullptr, Name + ".addr");
+  FakeVal = FakeValAddr;
+
+  if (M.getDataLayout().getAllocaAddrSpace() != 0) {
+    // Add additional casts to enforce pointers in zero address space
+    FakeVal = new AddrSpaceCastInst(
+        FakeValAddr, PointerType ::get(M.getContext(), 0), "tid.addr.ascast");
+    FakeVal->insertAfter(FakeValAddr->getIterator());
+    ToBeDeleted.push_back(FakeVal);
+  }
+
   ToBeDeleted.push_back(FakeValAddr);
 
-  if (AsPtr) {
-    FakeVal = FakeValAddr;
-  } else {
+  if (!AsPtr) {
     FakeVal =
         Builder.CreateLoad(Builder.getInt32Ty(), FakeValAddr, Name + ".val");
     ToBeDeleted.push_back(FakeVal);
@@ -1941,7 +1949,7 @@ OpenMPIRBuilder::InsertPointOrErrorTy OpenMPIRBuilder::createTask(
   // Add the thread ID argument.
   SmallVector<Instruction *, 4> ToBeDeleted;
   OI.ExcludeArgsFromAggregate.push_back(createFakeIntVal(
-      Builder, AllocaIP, ToBeDeleted, TaskAllocaIP, "global.tid", false));
+      Builder, M, AllocaIP, ToBeDeleted, TaskAllocaIP, "global.tid", false));
 
   OI.PostOutlineCB = [this, Ident, Tied, Final, IfCondition, Dependencies,
                       Mergeable, Priority, EventHandle, TaskAllocaBB,
@@ -7541,8 +7549,9 @@ OpenMPIRBuilder::InsertPointOrErrorTy OpenMPIRBuilder::emitTargetTask(
 
   // Add the thread ID argument.
   SmallVector<Instruction *, 4> ToBeDeleted;
-  OI.ExcludeArgsFromAggregate.push_back(createFakeIntVal(
-      Builder, AllocaIP, ToBeDeleted, TargetTaskAllocaIP, "global.tid", false));
+  OI.ExcludeArgsFromAggregate.push_back(
+      createFakeIntVal(Builder, M, AllocaIP, ToBeDeleted, TargetTaskAllocaIP,
+                       "global.tid", false));
 
   // Generate the task body which will subsequently be outlined.
   Builder.restoreIP(TargetTaskBodyIP);
@@ -9532,9 +9541,9 @@ OpenMPIRBuilder::createTeams(const LocationDescription &Loc,
   SmallVector<Instruction *, 8> ToBeDeleted;
   InsertPointTy OuterAllocaIP(&OuterAllocaBB, OuterAllocaBB.begin());
   OI.ExcludeArgsFromAggregate.push_back(createFakeIntVal(
-      Builder, OuterAllocaIP, ToBeDeleted, AllocaIP, "gid", true));
+      Builder, M, OuterAllocaIP, ToBeDeleted, AllocaIP, "gid", true));
   OI.ExcludeArgsFromAggregate.push_back(createFakeIntVal(
-      Builder, OuterAllocaIP, ToBeDeleted, AllocaIP, "tid", true));
+      Builder, M, OuterAllocaIP, ToBeDeleted, AllocaIP, "tid", true));
 
   auto HostPostOutlineCB = [this, Ident,
                             ToBeDeleted](Function &OutlinedFn) mutable {