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These changes plus:

```c++
#define cublasGemmBatchedEx hipblasGemmBatchedEx
```

are needed to compile with ROCM. I haven't done performance testing, but it seems to work.

I couldn't figure out how to propose a change for lines outside what the pull changed, also this is the first time trying to create a multi-part review so please forgive me if I mess something up.

ggml-cuda.cu

@@ -7154,9 +7154,9 @@ static void ggml_cuda_mul_mat_mat_batched_cublas(const ggml_tensor * src0, const
         }
 
         // allocate device memory for pointers
-        void ** src0_ptrs_as = nullptr;
-        void ** src1_ptrs_as = nullptr;
-        void **  dst_ptrs_as = nullptr;
+        const void ** src0_ptrs_as = nullptr;
+        const void ** src1_ptrs_as = nullptr;
+        void       **  dst_ptrs_as = nullptr;
 
         CUDA_CHECK(cudaMalloc(&src0_ptrs_as, ne23*sizeof(void *)));
         CUDA_CHECK(cudaMalloc(&src1_ptrs_as, ne23*sizeof(void *)));
@@ -7170,9 +7170,9 @@ static void ggml_cuda_mul_mat_mat_batched_cublas(const ggml_tensor * src0, const
         CUBLAS_CHECK(
         cublasGemmBatchedEx(g_cublas_handles[id], CUBLAS_OP_T, CUBLAS_OP_N,
                 ne01, ne11, ne10,
-                &alpha_f16, (void **) src0_ptrs_as, CUDA_R_16F, nb01/sizeof(half),
-                            (void **) src1_ptrs_as, CUDA_R_16F, nb11/sizeof(float),
-                &beta_f16,  (void **)  dst_ptrs_as, CUDA_R_16F, ne01,
+                &alpha_f16, (const void **) src0_ptrs_as, CUDA_R_16F, nb01/sizeof(half),
+                            (const void **) src1_ptrs_as, CUDA_R_16F, nb11/sizeof(float),
+                &beta_f16,  (      void **)  dst_ptrs_as, CUDA_R_16F, ne01,
                 ne23,
                 CUBLAS_COMPUTE_16F,
                 CUBLAS_GEMM_DEFAULT_TENSOR_OP));