[llvm] [mlir] [mlir][llvmir][OpenMP] Translate affinity clause in task construct to llvmir (PR #182223)

[via llvm-commits]

================
@@ -11532,6 +11541,55 @@ void OpenMPIRBuilder::loadOffloadInfoMetadata(vfs::FileSystem &VFS,
   loadOffloadInfoMetadata(*M.get());
 }
 
+OpenMPIRBuilder::InsertPointOrErrorTy OpenMPIRBuilder::createIteratorLoop(
+    LocationDescription Loc, llvm::Value *TripCount, IteratorBodyGenTy BodyGen,
+    llvm::StringRef Name) {
+  Builder.restoreIP(Loc.IP);
+
+  BasicBlock *CurBB = Builder.GetInsertBlock();
+  assert(CurBB &&
+         "expected a valid insertion block for creating an iterator loop");
+  Function *F = CurBB->getParent();
+
+  InsertPointTy SplitIP = Builder.saveIP();
+  if (SplitIP.getPoint() == CurBB->end())
+    if (Instruction *Terminator = CurBB->getTerminator())
+      SplitIP = InsertPointTy(CurBB, Terminator->getIterator());
+
+  BasicBlock *ContBB =
+      splitBB(SplitIP, /*CreateBranch=*/false,
+              Builder.getCurrentDebugLocation(), "omp.it.cont");
+
+  CanonicalLoopInfo *CLI =
+      createLoopSkeleton(Builder.getCurrentDebugLocation(), TripCount, F,
+                         /*PreInsertBefore=*/ContBB,
+                         /*PostInsertBefore=*/ContBB, Name);
+
+  // Enter loop from original block.
+  redirectTo(CurBB, CLI->getPreheader(), Builder.getCurrentDebugLocation());
+
+  // Remove the unconditional branch inserted by createLoopSkeleton in the body
+  if (Instruction *T = CLI->getBody()->getTerminator())
+    T->eraseFromParent();
+
+  InsertPointTy BodyIP = CLI->getBodyIP();
+  if (llvm::Error Err = BodyGen(BodyIP, CLI->getIndVar()))
+    return Err;
----------------
chichunchen wrote:

The bodyGen for the iterator loop always comes with a terminator by design: the omp.iterator region ends with `omp.yield <entry>`, and lowering that region emits the body terminator.
In `convertIteratorRegion` you can see that terminator is not explicitly added but comes from the `moduleTranslation.convertBlock()`.

https://github.com/llvm/llvm-project/pull/182223