mem-cache: Use shouldAllocate() instead of CPack's decompress()
Split decompression functionality using the proper function to
determine if a dictionary entry should be allocated after
decompression or not.
Change-Id: I4995304f4c4508c03c9fc1685f04511622969556
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21146
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
diff --git a/src/mem/cache/compressors/cpack.cc b/src/mem/cache/compressors/cpack.cc
index 1192963..625bedc 100644
--- a/src/mem/cache/compressors/cpack.cc
+++ b/src/mem/cache/compressors/cpack.cc
@@ -159,8 +159,6 @@
uint32_t
CPack::decompressWord(const Pattern* pattern)
{
- std::array<uint8_t, 4> data;
-
// Search for matching entry
std::vector<std::array<uint8_t, 4>>::iterator entry_it =
dictionary.begin();
@@ -168,7 +166,8 @@
// Decompress the match. If the decompressed value must be added to
// the dictionary, do it
- if (pattern->decompress(*entry_it, data)) {
+ const std::array<uint8_t, 4> data = pattern->decompress(*entry_it);
+ if (pattern->shouldAllocate()) {
dictionary[numEntries++] = data;
}
diff --git a/src/mem/cache/compressors/cpack.hh b/src/mem/cache/compressors/cpack.hh
index 664a376..1a271ee 100644
--- a/src/mem/cache/compressors/cpack.hh
+++ b/src/mem/cache/compressors/cpack.hh
@@ -357,11 +357,10 @@
* its data.
*
* @param dict_bytes The bytes in the corresponding matching entry.
- * @param data The decompressed pattern.
- * @return Whether entry should be added to dictionary or not.
+ * @return The decompressed pattern.
*/
- virtual bool decompress(const std::array<uint8_t, 4> dict_bytes,
- std::array<uint8_t, 4>& data) const = 0;
+ virtual std::array<uint8_t, 4> decompress(
+ const std::array<uint8_t, 4> dict_bytes) const = 0;
};
class CPack::PatternZZZZ : public Pattern
@@ -378,11 +377,10 @@
(bytes[0] == 0);
}
- bool decompress(const std::array<uint8_t, 4> dict_bytes,
- std::array<uint8_t, 4>& data) const override
+ std::array<uint8_t, 4>
+ decompress(const std::array<uint8_t, 4> dict_bytes) const override
{
- data = {0, 0, 0, 0};
- return false;
+ return {0, 0, 0, 0};
}
};
@@ -407,11 +405,10 @@
return true;
}
- bool decompress(const std::array<uint8_t, 4> dict_bytes,
- std::array<uint8_t, 4>& data) const override
+ std::array<uint8_t, 4>
+ decompress(const std::array<uint8_t, 4> dict_bytes) const override
{
- data = bytes;
- return true;
+ return bytes;
}
};
@@ -428,11 +425,10 @@
return (bytes == dict_bytes) && (match_location >= 0);
}
- bool decompress(const std::array<uint8_t, 4> dict_bytes,
- std::array<uint8_t, 4>& data) const override
+ std::array<uint8_t, 4>
+ decompress(const std::array<uint8_t, 4> dict_bytes) const override
{
- data = dict_bytes;
- return true;
+ return dict_bytes;
}
};
@@ -461,11 +457,10 @@
}
- bool decompress(const std::array<uint8_t, 4> dict_bytes,
- std::array<uint8_t, 4>& data) const override
+ std::array<uint8_t, 4>
+ decompress(const std::array<uint8_t, 4> dict_bytes) const override
{
- data = {byte0, byte1, dict_bytes[2], dict_bytes[3]};
- return true;
+ return {byte0, byte1, dict_bytes[2], dict_bytes[3]};
}
};
@@ -489,11 +484,10 @@
(bytes[0] != 0);
}
- bool decompress(const std::array<uint8_t, 4> dict_bytes,
- std::array<uint8_t, 4>& data) const override
+ std::array<uint8_t, 4>
+ decompress(const std::array<uint8_t, 4> dict_bytes) const override
{
- data = {byte, 0, 0, 0};
- return false;
+ return {byte, 0, 0, 0};
}
};
@@ -519,11 +513,10 @@
(match_location >= 0);
}
- bool decompress(const std::array<uint8_t, 4> dict_bytes,
- std::array<uint8_t, 4>& data) const override
+ std::array<uint8_t, 4>
+ decompress(const std::array<uint8_t, 4> dict_bytes) const override
{
- data = {byte, dict_bytes[1], dict_bytes[2], dict_bytes[3]};
- return true;
+ return {byte, dict_bytes[1], dict_bytes[2], dict_bytes[3]};
}
};