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+/*
+ * Copyright (c) 2019 Inria
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Daniel Carvalho
+ */
+
+/** @file
+ * Implementation of a base delta immediate compressor. @see BDI
+ */
+
+#ifndef __MEM_CACHE_COMPRESSORS_BASE_DELTA_IMPL_HH__
+#define __MEM_CACHE_COMPRESSORS_BASE_DELTA_IMPL_HH__
+
+#include "debug/CacheComp.hh"
+#include "mem/cache/compressors/base_delta.hh"
+#include "mem/cache/compressors/dictionary_compressor_impl.hh"
+
+template <class BaseType, std::size_t DeltaSizeBits>
+BaseDelta<BaseType, DeltaSizeBits>::BaseDelta(const Params *p)
+    : DictionaryCompressor<BaseType>(p)
+{
+}
+
+template <class BaseType, std::size_t DeltaSizeBits>
+void
+BaseDelta<BaseType, DeltaSizeBits>::resetDictionary()
+{
+    DictionaryCompressor<BaseType>::resetDictionary();
+
+    // Add zero base for the immediate values
+    addToDictionary(DictionaryCompressor<BaseType>::toDictionaryEntry(0));
+}
+
+template <class BaseType, std::size_t DeltaSizeBits>
+void
+BaseDelta<BaseType, DeltaSizeBits>::addToDictionary(DictionaryEntry data)
+{
+    assert(DictionaryCompressor<BaseType>::numEntries <
+        DictionaryCompressor<BaseType>::dictionarySize);
+    DictionaryCompressor<BaseType>::dictionary[
+        DictionaryCompressor<BaseType>::numEntries++] = data;
+}
+
+template <class BaseType, std::size_t DeltaSizeBits>
+std::unique_ptr<BaseCacheCompressor::CompressionData>
+BaseDelta<BaseType, DeltaSizeBits>::compress(const uint64_t* data,
+    Cycles& comp_lat, Cycles& decomp_lat)
+{
+    std::unique_ptr<BaseCacheCompressor::CompressionData> comp_data =
+        DictionaryCompressor<BaseType>::compress(data);
+
+    // If there are more bases than the maximum, the compressor failed.
+    // Otherwise, we have to take into account all bases that have not
+    // been used, considering that there is an implicit zero base that
+    // does not need to be added to the final size.
+    const int diff = DEFAULT_MAX_NUM_BASES -
+        DictionaryCompressor<BaseType>::numEntries;
+    if (diff < 0) {
+        comp_data->setSizeBits(DictionaryCompressor<BaseType>::blkSize * 8);
+        DPRINTF(CacheComp, "Base%dDelta%d compression failed\n",
+            8 * sizeof(BaseType), DeltaSizeBits);
+    } else if (diff > 0) {
+        comp_data->setSizeBits(comp_data->getSizeBits() +
+            8 * sizeof(BaseType) * diff);
+    }
+
+    // Set compression latency (Assumes 1 cycle per entry and 1 cycle for
+    // packing)
+    comp_lat = Cycles(1 + (DictionaryCompressor<BaseType>::blkSize /
+        sizeof(BaseType)));
+
+    // Set decompression latency
+    decomp_lat = Cycles(1);
+
+    // Return compressed line
+    return comp_data;
+}
+
+#endif //__MEM_CACHE_COMPRESSORS_BASE_DELTA_IMPL_HH__