mem-cache: Privatize extractSet

Only BaseSetAssoc uses extractSet(). Besides, skewed caches need
the way information to know which set an address is located at.

Change-Id: Id222e907dc550d053018561bb2683cfc415471ec
Reviewed-on: https://gem5-review.googlesource.com/9962
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>

src/mem/cache/tags/base.hh

@@ -288,9 +288,6 @@ class BaseTags : public ClockedObject
      */
     virtual Addr regenerateBlkAddr(const CacheBlk* blk) const = 0;
 
-    virtual int extractSet(Addr addr) const = 0;
-
-
     /**
      * Visit each block in the tags and apply a visitor
      *

src/mem/cache/tags/base_set_assoc.hh

@@ -278,16 +278,6 @@ class BaseSetAssoc : public BaseTags
         return (addr >> tagShift);
     }
 
-    /**
-     * Calculate the set index from the address.
-     * @param addr The address to get the set from.
-     * @return The set index of the address.
-     */
-    int extractSet(Addr addr) const override
-    {
-        return ((addr >> setShift) & setMask);
-    }
-
     /**
      * Regenerate the block address from the tag and set.
      *
@@ -313,6 +303,18 @@ class BaseSetAssoc : public BaseTags
         }
         return false;
     }
+
+  private:
+    /**
+     * Calculate the set index from the address.
+     *
+     * @param addr The address to get the set from.
+     * @return The set index of the address.
+     */
+    int extractSet(Addr addr) const
+    {
+        return ((addr >> setShift) & setMask);
+    }
 };
 
 #endif //__MEM_CACHE_TAGS_BASE_SET_ASSOC_HH__

src/mem/cache/tags/fa_lru.hh

@@ -220,16 +220,6 @@ class FALRU : public BaseTags
         return blkAlign(addr);
     }
 
-    /**
-     * Return the set of an address. Only one set in a fully associative cache.
-     * @param addr The address to get the set from.
-     * @return 0.
-     */
-    int extractSet(Addr addr) const override
-    {
-        return 0;
-    }
-
     /**
      * Regenerate the block address from the tag.
      *