diff --git a/mlir/include/mlir/Dialect/StandardOps/Transforms/Passes.h b/mlir/include/mlir/Dialect/StandardOps/Transforms/Passes.h
--- a/mlir/include/mlir/Dialect/StandardOps/Transforms/Passes.h
+++ b/mlir/include/mlir/Dialect/StandardOps/Transforms/Passes.h
@@ -20,10 +20,18 @@
 namespace mlir {
 
 class Pass;
+class MLIRContext;
+class OwningRewritePatternList;
 
 /// Creates an instance of the ExpandAtomic pass.
 std::unique_ptr<Pass> createExpandAtomicPass();
 
+/// Creates an instance of the ExpandTanh pass.
+std::unique_ptr<Pass> createExpandTanhPass();
+
+void populateExpandTanhPattern(OwningRewritePatternList &patterns,
+                               MLIRContext *ctx);
+
 } // end namespace mlir
 
 #endif // MLIR_DIALECT_STANDARD_TRANSFORMS_PASSES_H_
diff --git a/mlir/include/mlir/Dialect/StandardOps/Transforms/Passes.td b/mlir/include/mlir/Dialect/StandardOps/Transforms/Passes.td
--- a/mlir/include/mlir/Dialect/StandardOps/Transforms/Passes.td
+++ b/mlir/include/mlir/Dialect/StandardOps/Transforms/Passes.td
@@ -16,4 +16,9 @@
   let constructor = "mlir::createExpandAtomicPass()";
 }
 
+def ExpandTanh : FunctionPass<"expand-tanh"> {
+  let summary = "Expands TanhOp into ExpOp form.";
+  let constructor = "mlir::createExpandTanhPass()";
+}
+
 #endif // MLIR_DIALECT_STANDARD_TRANSFORMS_PASSES
diff --git a/mlir/lib/Conversion/LinalgToLLVM/LinalgToLLVM.cpp b/mlir/lib/Conversion/LinalgToLLVM/LinalgToLLVM.cpp
--- a/mlir/lib/Conversion/LinalgToLLVM/LinalgToLLVM.cpp
+++ b/mlir/lib/Conversion/LinalgToLLVM/LinalgToLLVM.cpp
@@ -20,6 +20,7 @@
 #include "mlir/Dialect/Linalg/IR/LinalgTypes.h"
 #include "mlir/Dialect/Linalg/Passes.h"
 #include "mlir/Dialect/StandardOps/EDSC/Intrinsics.h"
+#include "mlir/Dialect/StandardOps/Transforms/Passes.h"
 #include "mlir/IR/AffineExpr.h"
 #include "mlir/IR/AffineMap.h"
 #include "mlir/IR/Attributes.h"
@@ -377,6 +378,7 @@
   populateAffineToStdConversionPatterns(patterns, &getContext());
   populateLoopToStdConversionPatterns(patterns, &getContext());
   populateStdToLLVMConversionPatterns(converter, patterns);
+  populateExpandTanhPattern(patterns, &getContext());
   populateVectorToSCFConversionPatterns(patterns, &getContext());
   populateVectorToLLVMMatrixConversionPatterns(converter, patterns);
   populateVectorToLLVMConversionPatterns(converter, patterns);
diff --git a/mlir/lib/Dialect/StandardOps/Transforms/CMakeLists.txt b/mlir/lib/Dialect/StandardOps/Transforms/CMakeLists.txt
--- a/mlir/lib/Dialect/StandardOps/Transforms/CMakeLists.txt
+++ b/mlir/lib/Dialect/StandardOps/Transforms/CMakeLists.txt
@@ -1,5 +1,6 @@
 add_mlir_dialect_library(MLIRStandardOpsTransforms
   ExpandAtomic.cpp
+  ExpandTanh.cpp
   FuncConversions.cpp
 
   ADDITIONAL_HEADER_DIRS
diff --git a/mlir/test/Dialect/Standard/expand-tanh.mlir b/mlir/test/Dialect/Standard/expand-tanh.mlir
new file mode 100644
--- /dev/null
+++ b/mlir/test/Dialect/Standard/expand-tanh.mlir
@@ -0,0 +1,23 @@
+// RUN: mlir-opt %s -expand-tanh | FileCheck %s
+
+// CHECK-LABEL: func @tanh
+func @tanh(%arg: f32) -> f32 {
+  %res = tanh %arg : f32
+  return %res : f32
+}
+// CHECK: %[[ONE:.+]] = constant 1.000000e+00 : f32
+// CHECK: %[[TWO:.+]] = constant 2.000000e+00 : f32
+// CHECK: %[[XX:.+]] = mulf %arg0, %[[TWO]] : f32
+// CHECK: %[[NEGXX:.+]] = negf %[[XX]] : f32
+// CHECK: %[[EXP1:.+]] = exp %[[NEGXX]] : f32
+// CHECK: %[[DIVIDEND1:.+]] = subf %[[ONE]], %[[EXP1]] : f32
+// CHECK: %[[DIVISOR1:.+]] = addf %[[ONE]], %[[EXP1]] : f32
+// CHECK: %[[RES1:.+]] = divf %[[DIVIDEND1]], %[[DIVISOR1]] : f32
+// CHECK: %[[EXP2:.+]] = exp %[[XX]] : f32
+// CHECK: %[[DIVIDEND2:.+]] = subf %[[EXP2]], %[[ONE]] : f32
+// CHECK: %[[DIVISOR2:.+]] = addf %[[EXP2]], %[[ONE]] : f32
+// CHECK: %[[RES2:.+]] = divf %[[DIVIDEND2]], %[[DIVISOR2]] : f32
+// CHECK: %[[ZERO:.+]] = constant 0.000000e+00 : f32
+// CHECK: %[[COND:.+]] = cmpf "oge", %arg0, %[[ZERO]] : f32
+// CHECK: %[[RESULT:.+]] = select %[[COND]], %[[RES1]], %[[RES2]] : f32
+// CHECK: return %[[RESULT]]