fix unused var error (#9908)

Author: kexinzhao

paddle/fluid/operators/math/math_function.cu

@@ -268,6 +268,7 @@ void batched_gemm<platform::CUDADeviceContext, float16>(
     const CBLAS_TRANSPOSE transB, const int M, const int N, const int K,
     const float16 alpha, const float16* A, const float16* B, const float16 beta,
     float16* C, const int batchCount, const int strideA, const int strideB) {
+#if CUDA_VERSION >= 8000
   // Note that cublas follows fortran order, so the order is different from
   // the cblas convention.
   int lda = (transA == CblasNoTrans) ? K : M;
@@ -289,7 +290,6 @@ void batched_gemm<platform::CUDADeviceContext, float16>(
   PADDLE_ENFORCE_GE(context.GetComputeCapability(), 53,
                     "cublas Hgemm requires GPU compute capability >= 53");
 
-#if CUDA_VERSION >= 8000
   PADDLE_ENFORCE(platform::dynload::cublasHgemmStridedBatched(
       context.cublas_handle(), cuTransB, cuTransA, N, M, K, &h_alpha, h_B, ldb,
       strideB, h_A, lda, strideA, &h_beta, h_C, ldc, strideC, batchCount));
@@ -304,6 +304,7 @@ void batched_gemm<platform::CUDADeviceContext, float>(
     const CBLAS_TRANSPOSE transB, const int M, const int N, const int K,
     const float alpha, const float* A, const float* B, const float beta,
     float* C, const int batchCount, const int strideA, const int strideB) {
+#if CUDA_VERSION >= 8000
   // Note that cublas follows fortran order, so the order is different from
   // the cblas convention.
   int lda = (transA == CblasNoTrans) ? K : M;
@@ -315,7 +316,6 @@ void batched_gemm<platform::CUDADeviceContext, float>(
       (transB == CblasNoTrans) ? CUBLAS_OP_N : CUBLAS_OP_T;
   const int strideC = M * N;
 
-#if CUDA_VERSION >= 8000
   PADDLE_ENFORCE(platform::dynload::cublasSgemmStridedBatched(
       context.cublas_handle(), cuTransB, cuTransA, N, M, K, &alpha, B, ldb,
       strideB, A, lda, strideA, &beta, C, ldc, strideC, batchCount));
@@ -330,6 +330,7 @@ void batched_gemm<platform::CUDADeviceContext, double>(
     const CBLAS_TRANSPOSE transB, const int M, const int N, const int K,
     const double alpha, const double* A, const double* B, const double beta,
     double* C, const int batchCount, const int strideA, const int strideB) {
+#if CUDA_VERSION >= 8000
   // Note that cublas follows fortran order, so the order is different from
   // the cblas convention.
   int lda = (transA == CblasNoTrans) ? K : M;
@@ -341,7 +342,6 @@ void batched_gemm<platform::CUDADeviceContext, double>(
       (transB == CblasNoTrans) ? CUBLAS_OP_N : CUBLAS_OP_T;
   const int strideC = M * N;
 
-#if CUDA_VERSION >= 8000
   PADDLE_ENFORCE(platform::dynload::cublasDgemmStridedBatched(
       context.cublas_handle(), cuTransB, cuTransA, N, M, K, &alpha, B, ldb,
       strideB, A, lda, strideA, &beta, C, ldc, strideC, batchCount));