diff --git a/mlir/lib/Dialect/LLVMIR/Transforms/LegalizeForExport.cpp b/mlir/lib/Dialect/LLVMIR/Transforms/LegalizeForExport.cpp
--- a/mlir/lib/Dialect/LLVMIR/Transforms/LegalizeForExport.cpp
+++ b/mlir/lib/Dialect/LLVMIR/Transforms/LegalizeForExport.cpp
@@ -15,7 +15,14 @@
 
 using namespace mlir;
 
+/// If the given block has the same successor with different arguments,
+/// introduce dummy successor blocks so that all successors of the given block
+/// are different.
 static void ensureDistinctSuccessors(Block &bb) {
+  // Early exit if the block cannot have successors.
+  if (bb.empty() || !bb.back().mightHaveTrait<OpTrait::IsTerminator>())
+    return;
+
   auto *terminator = bb.getTerminator();
 
   // Find repeated successors with arguments.
@@ -49,9 +56,11 @@
 }
 
 void mlir::LLVM::ensureDistinctSuccessors(Operation *op) {
-  op->walk([](LLVMFuncOp f) {
-    for (auto &bb : f) {
-      ::ensureDistinctSuccessors(bb);
+  op->walk([](Operation *nested) {
+    for (Region &region : llvm::make_early_inc_range(nested->getRegions())) {
+      for (Block &block : llvm::make_early_inc_range(region)) {
+        ::ensureDistinctSuccessors(block);
+      }
     }
   });
 }
diff --git a/mlir/test/Dialect/LLVMIR/legalize-for-export.mlir b/mlir/test/Dialect/LLVMIR/legalize-for-export.mlir
--- a/mlir/test/Dialect/LLVMIR/legalize-for-export.mlir
+++ b/mlir/test/Dialect/LLVMIR/legalize-for-export.mlir
@@ -29,3 +29,17 @@
 
 // CHECK-NOT: ^{{.*}}:
 }
+
+// CHECK: @repeated_successor_openmp
+llvm.func @repeated_successor_openmp(%arg0: i64, %arg1: i64, %arg2: i64, %arg3: i1) {
+  omp.wsloop (%arg4) : i64 = (%arg0) to (%arg1) step (%arg2)  {
+    // CHECK: llvm.cond_br %{{.*}}, ^[[BB1:.*]]({{.*}}), ^[[BB2:.*]]({{.*}})
+    llvm.cond_br %arg3, ^bb1(%arg0 : i64), ^bb1(%arg1 : i64)
+  // CHECK: ^[[BB1]]
+  ^bb1(%0: i64):  // 2 preds: ^bb0, ^bb0
+    omp.yield
+  // CHECK: ^[[BB2]](%[[ARG:.*]]: i64):
+  // CHECK:  llvm.br ^[[BB1]](%[[ARG]] : i64)
+  }
+  llvm.return
+}
diff --git a/mlir/test/Target/LLVMIR/openmp-llvm.mlir b/mlir/test/Target/LLVMIR/openmp-llvm.mlir
--- a/mlir/test/Target/LLVMIR/openmp-llvm.mlir
+++ b/mlir/test/Target/LLVMIR/openmp-llvm.mlir
@@ -892,3 +892,19 @@
   }
   llvm.return
 }
+
+// -----
+
+// Check that translation doesn't crash in presence of repeated successor
+// blocks with different arguments within OpenMP operations: LLVM cannot
+// represent this and a dummy block will be introduced for forwarding. The
+// introduction mechanism itself is tested elsewhere.
+// CHECK-LABEL: @repeated_successor
+llvm.func @repeated_successor(%arg0: i64, %arg1: i64, %arg2: i64, %arg3: i1) {
+  omp.wsloop (%arg4) : i64 = (%arg0) to (%arg1) step (%arg2)  {
+    llvm.cond_br %arg3, ^bb1(%arg0 : i64), ^bb1(%arg1 : i64)
+  ^bb1(%0: i64):  // 2 preds: ^bb0, ^bb0
+    omp.yield
+  }
+  llvm.return
+}