diff --git a/mlir/test/mlir-tblgen/op-decl.td b/mlir/test/mlir-tblgen/op-decl-and-defs.td
rename from mlir/test/mlir-tblgen/op-decl.td
rename to mlir/test/mlir-tblgen/op-decl-and-defs.td
--- a/mlir/test/mlir-tblgen/op-decl.td
+++ b/mlir/test/mlir-tblgen/op-decl-and-defs.td
@@ -1,7 +1,9 @@
-// RUN: mlir-tblgen -gen-op-decls -I %S/../../include %s | FileCheck  %s
+// RUN: mlir-tblgen -gen-op-decls -I %S/../../include %s | FileCheck %s
 // RUN: mlir-tblgen -gen-op-decls -op-include-regex="test.a_op" -I %S/../../include %s | FileCheck  %s --check-prefix=REDUCE_INC
 // RUN: mlir-tblgen -gen-op-decls -op-exclude-regex="test.a_op" -I %S/../../include %s | FileCheck  %s --check-prefix=REDUCE_EXC
 
+// RUN: mlir-tblgen -gen-op-defs -I %S/../../include %s | FileCheck %s --check-prefix=DEFS
+
 include "mlir/IR/OpBase.td"
 include "mlir/Interfaces/InferTypeOpInterface.td"
 include "mlir/Interfaces/SideEffectInterfaces.td"
@@ -58,6 +60,8 @@
 // CHECK:   ::mlir::ValueRange b();
 // CHECK:   ::mlir::IntegerAttr attr1();
 // CHECK:   ::mlir::FloatAttr attr2();
+// CHECK:   ::mlir::Region &someRegion();
+// CHECK:   ::mlir::RegionRange someRegions();
 // CHECK: private:
 // CHECK:   ::mlir::ValueRange odsOperands;
 // CHECK: };
@@ -96,6 +100,13 @@
 // CHECK:   void displayGraph();
 // CHECK: };
 
+// DEFS-LABEL: NS::AOp definitions
+
+// DEFS: AOpAdaptor::AOpAdaptor(::mlir::ValueRange values, ::mlir::DictionaryAttr attrs, ::mlir::RegionRange regions) : odsOperands(values), odsAttrs(attrs), odsRegions(regions)
+// DEFS: ::mlir::RegionRange AOpAdaptor::getRegions()
+// DEFS: ::mlir::RegionRange AOpAdaptor::someRegions()
+// DEFS-NEXT: return odsRegions.drop_front(1);
+
 // Check AttrSizedOperandSegments
 // ---
 
diff --git a/mlir/tools/mlir-tblgen/OpDefinitionsGen.cpp b/mlir/tools/mlir-tblgen/OpDefinitionsGen.cpp
--- a/mlir/tools/mlir-tblgen/OpDefinitionsGen.cpp
+++ b/mlir/tools/mlir-tblgen/OpDefinitionsGen.cpp
@@ -2246,6 +2246,7 @@
     : op(op), adaptor(op.getAdaptorName()) {
   adaptor.newField("::mlir::ValueRange", "odsOperands");
   adaptor.newField("::mlir::DictionaryAttr", "odsAttrs");
+  adaptor.newField("::mlir::RegionRange", "odsRegions");
   const auto *attrSizedOperands =
       op.getTrait("::mlir::OpTrait::AttrSizedOperandSegments");
   {
@@ -2253,10 +2254,12 @@
     paramList.emplace_back("::mlir::ValueRange", "values");
     paramList.emplace_back("::mlir::DictionaryAttr", "attrs",
                            attrSizedOperands ? "" : "nullptr");
+    paramList.emplace_back("::mlir::RegionRange", "regions", "{}");
     auto *constructor = adaptor.addConstructorAndPrune(std::move(paramList));
 
     constructor->addMemberInitializer("odsOperands", "values");
     constructor->addMemberInitializer("odsAttrs", "attrs");
+    constructor->addMemberInitializer("odsRegions", "regions");
   }
 
   {
@@ -2264,8 +2267,13 @@
         llvm::formatv("{0}&", op.getCppClassName()).str(), "op");
     constructor->addMemberInitializer("odsOperands", "op->getOperands()");
     constructor->addMemberInitializer("odsAttrs", "op->getAttrDictionary()");
+    constructor->addMemberInitializer("odsRegions", "op->getRegions()");
   }
 
+  {
+    auto *m = adaptor.addMethodAndPrune("::mlir::ValueRange", "getOperands");
+    m->body() << "  return odsOperands;";
+  }
   std::string sizeAttrInit =
       formatv(adapterSegmentSizeAttrInitCode, "operand_segment_sizes");
   generateNamedOperandGetters(op, adaptor, sizeAttrInit,
@@ -2299,6 +2307,11 @@
     body << "  return attr;\n";
   };
 
+  {
+    auto *m =
+        adaptor.addMethodAndPrune("::mlir::DictionaryAttr", "getAttributes");
+    m->body() << "  return odsAttrs;";
+  }
   for (auto &namedAttr : op.getAttributes()) {
     const auto &name = namedAttr.name;
     const auto &attr = namedAttr.attr;
@@ -2306,6 +2319,27 @@
       emitAttr(name, attr);
   }
 
+  unsigned numRegions = op.getNumRegions();
+  if (numRegions > 0) {
+    auto *m = adaptor.addMethodAndPrune("::mlir::RegionRange", "getRegions");
+    m->body() << "  return odsRegions;";
+  }
+  for (unsigned i = 0; i < numRegions; ++i) {
+    const auto &region = op.getRegion(i);
+    if (region.name.empty())
+      continue;
+
+    // Generate the accessors for a variadic region.
+    if (region.isVariadic()) {
+      auto *m = adaptor.addMethodAndPrune("::mlir::RegionRange", region.name);
+      m->body() << formatv("  return odsRegions.drop_front({0});", i);
+      continue;
+    }
+
+    auto *m = adaptor.addMethodAndPrune("::mlir::Region &", region.name);
+    m->body() << formatv("  return *odsRegions[{0}];", i);
+  }
+
   // Add verification function.
   addVerification();
 }