diff --git a/src/mem/snoop_filter.cc b/src/mem/snoop_filter.cc
index 3e1dae6..8168c3d 100644
--- a/src/mem/snoop_filter.cc
+++ b/src/mem/snoop_filter.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2017 ARM Limited
+ * Copyright (c) 2013-2017,2019 ARM Limited
  * All rights reserved
  *
  * The license below extends only to copyright in the software and shall
@@ -49,11 +49,13 @@
 #include "debug/SnoopFilter.hh"
 #include "sim/system.hh"
 
+const int SnoopFilter::SNOOP_MASK_SIZE;
+
 void
 SnoopFilter::eraseIfNullEntry(SnoopFilterCache::iterator& sf_it)
 {
     SnoopItem& sf_item = sf_it->second;
-    if (!(sf_item.requested | sf_item.holder)) {
+    if ((sf_item.requested | sf_item.holder).none()) {
         cachedLocations.erase(sf_it);
         DPRINTF(SnoopFilter, "%s:   Removed SF entry.\n",
                 __func__);
@@ -96,8 +98,7 @@
 
     totRequests++;
     if (is_hit) {
-        // Single bit set -> value is a power of two
-        if (isPow2(interested))
+        if (interested.count() == 1)
             hitSingleRequests++;
         else
             hitMultiRequests++;
@@ -114,8 +115,9 @@
     if (cpkt->needsResponse()) {
         if (!cpkt->cacheResponding()) {
             // Max one request per address per port
-            panic_if(sf_item.requested & req_port, "double request :( " \
-                     "SF value %x.%x\n", sf_item.requested, sf_item.holder);
+            panic_if((sf_item.requested & req_port).any(),
+                     "double request :( SF value %x.%x\n",
+                     sf_item.requested, sf_item.holder);
 
             // Mark in-flight requests to distinguish later on
             sf_item.requested |= req_port;
@@ -126,7 +128,8 @@
             // to the CPU, already -> the response will not be seen by this
             // filter -> we do not need to keep the in-flight request, but make
             // sure that we know that that cluster has a copy
-            panic_if(!(sf_item.holder & req_port), "Need to hold the value!");
+            panic_if((sf_item.holder & req_port).none(),
+                     "Need to hold the value!");
             DPRINTF(SnoopFilter,
                     "%s: not marking request. SF value %x.%x\n",
                     __func__,  sf_item.requested, sf_item.holder);
@@ -134,7 +137,7 @@
     } else { // if (!cpkt->needsResponse())
         assert(cpkt->isEviction());
         // make sure that the sender actually had the line
-        panic_if(!(sf_item.holder & req_port), "requester %x is not a " \
+        panic_if((sf_item.holder & req_port).none(), "requester %x is not a " \
                  "holder :( SF value %x.%x\n", req_port,
                  sf_item.requested, sf_item.holder);
         // CleanEvicts and Writebacks -> the sender and all caches above
@@ -206,8 +209,8 @@
     SnoopMask interested = (sf_item.holder | sf_item.requested);
 
     totSnoops++;
-    // Single bit set -> value is a power of two
-    if (isPow2(interested))
+
+    if (interested.count() == 1)
         hitSingleSnoops++;
     else
         hitMultiSnoops++;
@@ -222,7 +225,7 @@
     assert(cpkt->isWriteback() || cpkt->req->isUncacheable() ||
            (cpkt->isInvalidate() == cpkt->needsWritable()) ||
            cpkt->req->isCacheMaintenance());
-    if (cpkt->isInvalidate() && !sf_item.requested) {
+    if (cpkt->isInvalidate() && sf_item.requested.none()) {
         // Early clear of the holder, if no other request is currently going on
         // @todo: This should possibly be updated even though we do not filter
         // upward snoops
@@ -266,11 +269,12 @@
             __func__,  sf_item.requested, sf_item.holder);
 
     // The source should have the line
-    panic_if(!(sf_item.holder & rsp_mask), "SF value %x.%x does not have "\
-             "the line\n", sf_item.requested, sf_item.holder);
+    panic_if((sf_item.holder & rsp_mask).none(),
+             "SF value %x.%x does not have the line\n",
+             sf_item.requested, sf_item.holder);
 
     // The destination should have had a request in
-    panic_if(!(sf_item.requested & req_mask), "SF value %x.%x missing "\
+    panic_if((sf_item.requested & req_mask).none(), "SF value %x.%x missing "\
              "the original request\n",  sf_item.requested, sf_item.holder);
 
     // If the snoop response has no sharers the line is passed in
@@ -287,7 +291,7 @@
     // @todo Deal with invalidating responses
     sf_item.holder |=  req_mask;
     sf_item.requested &= ~req_mask;
-    assert(sf_item.requested | sf_item.holder);
+    assert((sf_item.requested | sf_item.holder).any());
     DPRINTF(SnoopFilter, "%s:   new SF value %x.%x\n",
             __func__, sf_item.requested, sf_item.holder);
 }
@@ -359,8 +363,9 @@
             __func__,  sf_item.requested, sf_item.holder);
 
     // Make sure we have seen the actual request, too
-    panic_if(!(sf_item.requested & slave_mask), "SF value %x.%x missing "\
-             "request bit\n", sf_item.requested, sf_item.holder);
+    panic_if((sf_item.requested & slave_mask).none(),
+             "SF value %x.%x missing request bit\n",
+             sf_item.requested, sf_item.holder);
 
     sf_item.requested &= ~slave_mask;
     // Update the residency of the cache line.
@@ -376,7 +381,7 @@
         // Any other response implies that a cache above will have the
         // block.
         sf_item.holder |= slave_mask;
-        assert(sf_item.holder | sf_item.requested);
+        assert((sf_item.holder | sf_item.requested).any());
     }
     DPRINTF(SnoopFilter, "%s:   new SF value %x.%x\n",
             __func__, sf_item.requested, sf_item.holder);
diff --git a/src/mem/snoop_filter.hh b/src/mem/snoop_filter.hh
index 85cc75e..9c06615 100644
--- a/src/mem/snoop_filter.hh
+++ b/src/mem/snoop_filter.hh
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2016 ARM Limited
+ * Copyright (c) 2013-2016,2019 ARM Limited
  * All rights reserved
  *
  * The license below extends only to copyright in the software and shall
@@ -45,6 +45,7 @@
 #ifndef __MEM_SNOOP_FILTER_HH__
 #define __MEM_SNOOP_FILTER_HH__
 
+#include <bitset>
 #include <unordered_map>
 #include <utility>
 
@@ -86,6 +87,10 @@
  */
 class SnoopFilter : public SimObject {
   public:
+
+    // Change for systems with more than 256 ports tracked by this object
+    static const int SNOOP_MASK_SIZE = 256;
+
     typedef std::vector<QueuedSlavePort*> SnoopList;
 
     SnoopFilter (const SnoopFilterParams *p) :
@@ -114,9 +119,9 @@
         }
 
         // make sure we can deal with this many ports
-        fatal_if(id > 8 * sizeof(SnoopMask),
+        fatal_if(id > SNOOP_MASK_SIZE,
                  "Snoop filter only supports %d snooping ports, got %d\n",
-                 8 * sizeof(SnoopMask), id);
+                 SNOOP_MASK_SIZE, id);
     }
 
     /**
@@ -198,13 +203,9 @@
 
     /**
      * The underlying type for the bitmask we use for tracking. This
-     * limits the number of snooping ports supported per crossbar. For
-     * the moment it is an uint64_t to offer maximum
-     * scalability. However, it is possible to use e.g. a uint16_t or
-     * uint32_to slim down the footprint of the hash map (and
-     * ultimately improve the simulation performance).
+     * limits the number of snooping ports supported per crossbar.
      */
-    typedef uint64_t SnoopMask;
+    typedef std::bitset<SNOOP_MASK_SIZE> SnoopMask;
 
     /**
     * Per cache line item tracking a bitmask of SlavePorts who have an
@@ -314,7 +315,7 @@
 {
     SnoopList res;
     for (const auto& p : slavePorts)
-        if (port_mask & portToMask(*p))
+        if ((port_mask & portToMask(*p)).any())
             res.push_back(p);
     return res;
 }