disable xsmm with float16

Author: tensor-tang

paddle/fluid/operators/math/blas_impl.h

@@ -162,10 +162,10 @@ struct CBlas<platform::float16> {
   }
 #endif
 };
+
 template <typename T>
-inline static bool UseXSMM(const int &m, const int &n, const int &k,
-                           bool transa, bool transb, const T &alpha,
-                           const T &beta) {
+inline bool UseXSMM(const int &m, const int &n, const int &k, bool transa,
+                    bool transb, const T &alpha, const T &beta) {
 #ifdef PADDLE_WITH_LIBXSMM
   // Refer to https://github.com/hfp/libxsmm/blob/master/README.md
   // But the threshold is custom
@@ -182,6 +182,14 @@ inline static bool UseXSMM(const int &m, const int &n, const int &k,
   return false;
 }
 
+template <>
+inline bool UseXSMM<platform::float16>(const int &m, const int &n, const int &k,
+                                       bool transa, bool transb,
+                                       const platform::float16 &alpha,
+                                       const platform::float16 &beta) {
+  return false;
+}
+
 template <>
 template <typename T>
 void Blas<platform::CPUDeviceContext>::GEMM(CBLAS_TRANSPOSE transA,
@@ -194,7 +202,6 @@ void Blas<platform::CPUDeviceContext>::GEMM(CBLAS_TRANSPOSE transA,
 #ifdef PADDLE_WITH_LIBXSMM
   if (UseXSMM(M, N, K, transA != CblasNoTrans, transB != CblasNoTrans, alpha,
               beta)) {
-    // refer to https://github.com/hfp/libxsmm/blob/master/README.md
     // Note: SMM use ColMajor
     const char transa = 'N';
     const char transb = 'N';