MEM: Add the PortId type and a corresponding id field to Port

This patch introduces the PortId type, moves the definition of
INVALID_PORT_ID to the Port class, and also gives every port an id to
reflect the fact that each element in a vector port has an
identifier/index.

Previously the bus and Ruby testers (and potentially other users of
the vector ports) added the id field in their port subclasses, and now
this functionality is always present as it is moved to the base class.

1 files changed, 23 insertions, 3 deletions

diff --git a/src/mem/port.hh b/src/mem/port.hh
index 61c92d8e4..e1f643e8e 100644
--- a/src/mem/port.hh
+++ b/src/mem/port.hh
@@ -79,6 +79,14 @@ class MemObject;
 class Port
 {
 
+  public:
+
+    /** A type name for the port identifier. */
+    typedef int PortId;
+
+    /** A symbolic name for the absence of a port id. */
+    static const PortId INVALID_PORT_ID = -1;
+
   private:
 
     /** Descriptive name (for DPRINTF output) */
@@ -86,6 +94,12 @@ class Port
 
   protected:
 
+    /**
+     * A numeric identifier to distinguish ports in a vector, and set
+     * to INVALID_PORT_ID in case this port is not part of a vector.
+     */
+    const PortId id;
+
     /** A pointer to the peer port.  */
     Port* peer;
 
@@ -97,8 +111,9 @@ class Port
      *
      * @param _name Port name including the owners name
      * @param _owner The MemObject that is the structural owner of this port
+     * @param _id A port identifier for vector ports
      */
-    Port(const std::string& _name, MemObject& _owner);
+    Port(const std::string& _name, MemObject& _owner, PortId _id);
 
     /**
      * Virtual destructor due to inheritance.
@@ -110,6 +125,9 @@ class Port
     /** Return port name (for DPRINTF). */
     const std::string name() const { return portName; }
 
+    /** Get the port id. */
+    PortId getId() const { return id; }
+
   protected:
 
     /** These functions are protected because they should only be
@@ -190,7 +208,8 @@ class MasterPort : public Port
 
   public:
 
-    MasterPort(const std::string& name, MemObject* owner);
+    MasterPort(const std::string& name, MemObject* owner,
+               PortId id = INVALID_PORT_ID);
     virtual ~MasterPort();
 
     void bind(SlavePort& slave_port);
@@ -286,7 +305,8 @@ class SlavePort : public Port
 
   public:
 
-    SlavePort(const std::string& name, MemObject* owner);
+    SlavePort(const std::string& name, MemObject* owner,
+              PortId id = INVALID_PORT_ID);
     virtual ~SlavePort();
 
     void bind(MasterPort& master_port);