mem-cache: Updated version of the Signature Path Prefetcher

This implementation is based in the description available in:
  Jinchun Kim, Seth H. Pugsley, Paul V. Gratz, A. L. Narasimha Reddy,
  Chris Wilkerson, and Zeshan Chishti. 2016.
  Path confidence based lookahead prefetching.
  In The 49th Annual IEEE/ACM International Symposium on Microarchitecture
  (MICRO-49). IEEE Press, Piscataway, NJ, USA, Article 60, 12 pages.

Change-Id: I4b8b54efef48ced7044bd535de9a69bca68d47d9
Reviewed-on: https://gem5-review.googlesource.com/c/14819
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/src/mem/cache/prefetch/base.hh b/src/mem/cache/prefetch/base.hh
index 63b0e1bed..06f77492d 100644
--- a/src/mem/cache/prefetch/base.hh
+++ b/src/mem/cache/prefetch/base.hh
@@ -214,6 +214,8 @@ class BasePrefetcher : public ClockedObject
     /** Determine if address is in cache miss queue */
     bool inMissQueue(Addr addr, bool is_secure) const;
 
+    bool hasBeenPrefetched(Addr addr, bool is_secure) const;
+
     /** Determine if addresses are on the same page */
     bool samePage(Addr a, Addr b) const;
     /** Determine the address of the block in which a lays */
@@ -229,6 +231,11 @@ class BasePrefetcher : public ClockedObject
 
     Stats::Scalar pfIssued;
 
+    /** Total prefetches issued */
+    uint64_t issuedPrefetches;
+    /** Total prefetches that has been useful */
+    uint64_t usefulPrefetches;
+
   public:
 
     BasePrefetcher(const BasePrefetcherParams *p);