Fix for beta!=0 in reduce (#1440)

* fix for beta!=0 in reduce

* add reviewers suggestions

example/12_reduce/reduce_blockwise_impl.hpp

 // SPDX-License-Identifier: MIT
-// Copyright (c) 2018-2023, Advanced Micro Devices, Inc. All rights reserved.
+// Copyright (c) 2018-2024, Advanced Micro Devices, Inc. All rights reserved.
 
 #pragma once
 
@@ -316,7 +316,17 @@ int reduce_blockwise_impl(bool do_verification,
 
     auto invoker_ptr = reduce.MakeInvokerPointer();
 
-    float avg_time = invoker_ptr->Run(argument_ptr.get(), StreamConfig{nullptr, time_kernel});
+    int log_level = 0, cold_niters = 5, nrepeat = 50;
+    if(beta != 0.0f)
+    {
+        std::cerr << "Warning: With beta != 0.0f there must be only one repeat for correct results "
+                     "since out memory is being overwritten."
+                  << std::endl;
+        cold_niters = 0;
+        nrepeat     = 1;
+    }
+    float avg_time = invoker_ptr->Run(
+        argument_ptr.get(), StreamConfig{nullptr, time_kernel, log_level, cold_niters, nrepeat});
 
     std::size_t num_bytes = invariant_total_length * reduce_total_length * sizeof(InOutDataType) +
                             invariant_total_length * sizeof(InOutDataType);

include/ck/tensor_operation/gpu/grid/gridwise_2d_multiple_reduction_multiblock.hpp

 // SPDX-License-Identifier: MIT
-// Copyright (c) 2018-2023, Advanced Micro Devices, Inc. All rights reserved.
+// Copyright (c) 2018-2024, Advanced Micro Devices, Inc. All rights reserved.
 
 #pragma once
 
@@ -258,7 +258,7 @@ struct GridwiseMultipleReduction_mk_to_m_multiblock
 
             if(thread_k_cluster_id == 0)
             {
-                if(block_group_size == 0 && !float_equal_zero{}(beta_values[iR]))
+                if(!float_equal_zero{}(beta_values[iR]))
                 {
                     StaticBuffer<AddressSpaceEnum::Vgpr, OutDataType, MThreadSliceSize, true>
                         priorDstValueBuf;

include/ck/tensor_operation/gpu/grid/gridwise_2d_reduction_multiblock.hpp

 // SPDX-License-Identifier: MIT
-// Copyright (c) 2018-2023, Advanced Micro Devices, Inc. All rights reserved.
+// Copyright (c) 2018-2024, Advanced Micro Devices, Inc. All rights reserved.
 
 #pragma once
 
@@ -244,7 +244,7 @@ struct GridwiseReduction_mk_to_m_multiblock
 
         if(thread_k_cluster_id == 0)
         {
-            if(block_group_size == 0 && !float_equal_zero{}(beta))
+            if(!float_equal_zero{}(beta))
             {
                 StaticBuffer<AddressSpaceEnum::Vgpr, OutDataType, MThreadSliceSize, true>
                     priorDstValueBuf;