diff --git a/mlir/include/mlir/Dialect/LLVMIR/LLVMIntrinsicOps.td b/mlir/include/mlir/Dialect/LLVMIR/LLVMIntrinsicOps.td
--- a/mlir/include/mlir/Dialect/LLVMIR/LLVMIntrinsicOps.td
+++ b/mlir/include/mlir/Dialect/LLVMIR/LLVMIntrinsicOps.td
@@ -680,6 +680,70 @@
   }];
 }
 
+//
+// Call an LLVM intrinsic
+//
+def LLVM_call_intrinsic : LLVM_Op<"call_intrinsic", [Pure]> {
+  let arguments = (ins StrAttr:$intrin, Variadic<LLVM_Type>:$args);
+  let results = (outs Variadic<LLVM_Type>:$results);
+  let llvmBuilder = [{
+    llvm::Module *module = builder.GetInsertBlock()->getModule();
+    llvm::Intrinsic::ID id = op.getIntrinsicEnum();
+    if (!id) {
+      assert(false && "Couldn't find the intrinsic!\n");
+    }
+    llvm::Function *fn;
+    if (!llvm::Intrinsic::isOverloaded(id)) {
+        fn = llvm::Intrinsic::getDeclaration(module, id, {});
+    } else {
+      SmallVector<llvm::Intrinsic::IITDescriptor, 8> Table;
+      getIntrinsicInfoTableEntries(id, Table);
+      ArrayRef<llvm::Intrinsic::IITDescriptor> TableRef = Table;
+
+      SmallVector<llvm::Type *, 8> opTys;
+      for (size_t i = 0; i < opInst.getNumOperands(); i++) {
+        opTys.push_back(moduleTranslation.convertType(
+          opInst.getOperand(i).getType()));
+      }
+
+      llvm::Type* resTy;
+      if (opInst.getNumResults() == 0) {
+        resTy = llvm::Type::getVoidTy(module->getContext());
+      } else {
+        resTy = moduleTranslation.convertType(opInst.getResult(0).getType());
+      }
+      llvm::FunctionType* FT = llvm::FunctionType::get(resTy, opTys, false);
+
+      SmallVector<llvm::Type *, 8> argTys;
+      if (llvm::Intrinsic::matchIntrinsicSignature(FT, TableRef, argTys) !=
+       llvm::Intrinsic::MatchIntrinsicTypesResult::MatchIntrinsicTypes_Match) {
+         assert (false && "Intrinsic type is not a match!\n");
+      }
+      if (llvm::Intrinsic::matchIntrinsicVarArg(FT->isVarArg(), TableRef)) {
+        assert (false && "Intrinsic variadic-ness is not a match!\n");
+      }
+
+      ArrayRef<llvm::Type *> ArgTys = argTys;
+      fn = llvm::Intrinsic::getDeclaration(module, id, ArgTys);
+    }
+
+    auto *inst = builder.CreateCall(fn,
+                  moduleTranslation.lookupValues(opInst.getOperands()));
+    if (opInst.getNumResults() == 1) {
+        moduleTranslation.mapValue(op->getResults().front())  = inst;
+    }
+  }];
+  let assemblyFormat = [{
+    $intrin `(` $args `)` `:` functional-type($args, $results) attr-dict
+  }];
+
+  let extraClassDeclaration = [{
+    llvm::Intrinsic::ID getIntrinsicEnum() {
+      return llvm::Function::lookupIntrinsicID(getIntrinAttr());
+    }
+  }];
+}
+
 //
 // LLVM Vector Predication operations.
 //
diff --git a/mlir/test/Dialect/LLVMIR/call-intrin.mlir b/mlir/test/Dialect/LLVMIR/call-intrin.mlir
new file mode 100644
--- /dev/null
+++ b/mlir/test/Dialect/LLVMIR/call-intrin.mlir
@@ -0,0 +1,54 @@
+// RUN: mlir-translate -mlir-to-llvmir -split-input-file %s | FileCheck %s
+
+// CHECK: ; ModuleID = 'LLVMDialectModule'
+// CHECK: source_filename = "LLVMDialectModule"
+// CHECK: declare ptr @malloc(i64)
+// CHECK: declare void @free(ptr)
+// CHECK: define <4 x float> @round_sse41() {
+// CHECK:  %1 = call <4 x float> @llvm.x86.sse41.round.ss(<4 x float> <float 0x3FC99999A0000000, float 0x3FC99999A0000000, float 0x3FC99999A0000000, float 0x3FC99999A0000000>, <4 x float> <float 0x3FC99999A0000000, float 0x3FC99999A0000000, float 0x3FC99999A0000000, float 0x3FC99999A0000000>, i32 1)
+// CHECK:  ret <4 x float> %1
+// CHECK: }
+llvm.func @round_sse41() -> vector<4xf32> {
+    %0 = llvm.mlir.constant(1 : i32) : i32
+    %1 = llvm.mlir.constant(dense<0.2> : vector<4xf32>) : vector<4xf32>
+    %res = llvm.call_intrinsic "llvm.x86.sse41.round.ss"(%1, %1, %0) : (vector<4xf32>, vector<4xf32>, i32) -> vector<4xf32> {}
+    llvm.return %res: vector<4xf32>
+}
+
+// -----
+
+// CHECK: ; ModuleID = 'LLVMDialectModule'
+// CHECK: source_filename = "LLVMDialectModule"
+
+// CHECK: declare ptr @malloc(i64)
+
+// CHECK: declare void @free(ptr)
+
+// CHECK: define float @round_overloaded() {
+// CHECK:   %1 = call float @llvm.round.f32(float 1.000000e+00)
+// CHECK:   ret float %1
+// CHECK: }
+llvm.func @round_overloaded() -> f32 {
+    %0 = llvm.mlir.constant(1.0 : f32) : f32
+    %res = llvm.call_intrinsic "llvm.round"(%0) : (f32) -> f32 {}
+    llvm.return %res: f32
+}
+
+// -----
+
+// CHECK: ; ModuleID = 'LLVMDialectModule'
+// CHECK: source_filename = "LLVMDialectModule"
+// CHECK: declare ptr @malloc(i64)
+// CHECK: declare void @free(ptr)
+// CHECK: define void @lifetime_start() {
+// CHECK:   %1 = alloca float, i8 1, align 4
+// CHECK:   call void @llvm.lifetime.start.p0(i64 4, ptr %1)
+// CHECK:   ret void
+// CHECK: }
+llvm.func @lifetime_start() {
+    %0 = llvm.mlir.constant(4 : i64) : i64
+    %1 = llvm.mlir.constant(1 : i8) : i8
+    %2 = llvm.alloca %1 x f32 : (i8) -> !llvm.ptr
+    llvm.call_intrinsic "llvm.lifetime.start"(%0, %2) : (i64, !llvm.ptr) -> () {}
+    llvm.return
+}