[clang] [llvm] [mlir] [OpenMP] Migrate GPU Reductions CodeGen from Clang to OMPIRBuilder (PR #80343)

[Akash Banerjee via cfe-commits]

================
@@ -2719,10 +4051,24 @@ getKmpcForStaticLoopForType(Type *Ty, OpenMPIRBuilder *OMPBuilder,
 static void createTargetLoopWorkshareCall(
     OpenMPIRBuilder *OMPBuilder, WorksharingLoopType LoopType,
     BasicBlock *InsertBlock, Value *Ident, Value *LoopBodyArg,
-    Type *ParallelTaskPtr, Value *TripCount, Function &LoopBodyFn) {
-  Type *TripCountTy = TripCount->getType();
+    Type *ParallelTaskPtr, Value *TripCountOrig, Function &LoopBodyFn) {
   Module &M = OMPBuilder->M;
   IRBuilder<> &Builder = OMPBuilder->Builder;
+  Value *TripCount = TripCountOrig;
+  // FIXME(JAN): The trip count is 1 larger than it should be for GPU, this may
+  // not be the right way to fix it, but this works for now.
----------------
TIFitis wrote:

This section of the code is never executed from Clang, so I'm not sure.

https://github.com/llvm/llvm-project/pull/80343