mem: Remove null-check bypassing in Packet::getPtr

This patch removes the parameter that enables bypassing the null check
in the Packet::getPtr method. A number of call sites assume the value
to be non-null.

The one odd case is the RubyTester, which issues zero-sized
prefetches(!), and despite being reads they had no valid data
pointer. This is now fixed, but the size oddity remains (unless anyone
object or has any good suggestions).

Finally, in the Ruby Sequencer, appropriate checks are made for flush
packets as they have no valid data pointer.

2 files changed, 10 insertions, 12 deletions

diff --git a/src/mem/ruby/system/DMASequencer.cc b/src/mem/ruby/system/DMASequencer.cc
index eb4ce6123..2c4c024b6 100644
--- a/src/mem/ruby/system/DMASequencer.cc
+++ b/src/mem/ruby/system/DMASequencer.cc
@@ -235,7 +235,7 @@ DMASequencer::makeRequest(PacketPtr pkt)
     }
 
     uint64_t paddr = pkt->getAddr();
-    uint8_t* data =  pkt->getPtr<uint8_t>(true);
+    uint8_t* data =  pkt->getPtr<uint8_t>();
     int len = pkt->getSize();
     bool write = pkt->isWrite();
 
diff --git a/src/mem/ruby/system/Sequencer.cc b/src/mem/ruby/system/Sequencer.cc
index bd82d9468..281ea22be 100644
--- a/src/mem/ruby/system/Sequencer.cc
+++ b/src/mem/ruby/system/Sequencer.cc
@@ -524,28 +524,23 @@ Sequencer::hitCallback(SequencerRequest* srequest, DataBlock& data,
              llscSuccess ? "Done" : "SC_Failed", "", "",
              request_address, total_latency);
 
-    // update the data
+    // update the data unless it is a non-data-carrying flush
     if (g_system_ptr->m_warmup_enabled) {
-        assert(pkt->getPtr<uint8_t>(false) != NULL);
-        data.setData(pkt->getPtr<uint8_t>(false),
+        data.setData(pkt->getPtr<uint8_t>(),
                      request_address.getOffset(), pkt->getSize());
-    } else if (pkt->getPtr<uint8_t>(true) != NULL) {
+    } else if (!pkt->isFlush()) {
         if ((type == RubyRequestType_LD) ||
             (type == RubyRequestType_IFETCH) ||
             (type == RubyRequestType_RMW_Read) ||
             (type == RubyRequestType_Locked_RMW_Read) ||
             (type == RubyRequestType_Load_Linked)) {
-            memcpy(pkt->getPtr<uint8_t>(true),
+            memcpy(pkt->getPtr<uint8_t>(),
                    data.getData(request_address.getOffset(), pkt->getSize()),
                    pkt->getSize());
         } else {
-            data.setData(pkt->getPtr<uint8_t>(true),
+            data.setData(pkt->getPtr<uint8_t>(),
                          request_address.getOffset(), pkt->getSize());
         }
-    } else {
-        DPRINTF(MemoryAccess,
-                "WARNING.  Data not transfered from Ruby to M5 for type %s\n",
-                RubyRequestType_to_string(type));
     }
 
     // If using the RubyTester, update the RubyTester sender state's
@@ -679,9 +674,12 @@ Sequencer::issueRequest(PacketPtr pkt, RubyRequestType secondary_type)
         pc = pkt->req->getPC();
     }
 
+    // check if the packet has data as for example prefetch and flush
+    // requests do not
     std::shared_ptr<RubyRequest> msg =
         std::make_shared<RubyRequest>(clockEdge(), pkt->getAddr(),
-                                      pkt->getPtr<uint8_t>(true),
+                                      pkt->isFlush() ?
+                                      nullptr : pkt->getPtr<uint8_t>(),
                                       pkt->getSize(), pc, secondary_type,
                                       RubyAccessMode_Supervisor, pkt,
                                       PrefetchBit_No, proc_id);