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-rw-r--r--cpu/o3/dep_graph.hh213
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diff --git a/cpu/o3/dep_graph.hh b/cpu/o3/dep_graph.hh
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+
+#ifndef __CPU_O3_DEP_GRAPH_HH__
+#define __CPU_O3_DEP_GRAPH_HH__
+
+#include "cpu/o3/comm.hh"
+
+template <class DynInstPtr>
+class DependencyEntry
+{
+ public:
+ DependencyEntry()
+ : inst(NULL), next(NULL)
+ { }
+
+ DynInstPtr inst;
+ //Might want to include data about what arch. register the
+ //dependence is waiting on.
+ DependencyEntry<DynInstPtr> *next;
+};
+
+template <class DynInstPtr>
+class DependencyGraph
+{
+ public:
+ typedef DependencyEntry<DynInstPtr> DepEntry;
+
+ DependencyGraph()
+ : numEntries(0), memAllocCounter(0), nodesTraversed(0), nodesRemoved(0)
+ { }
+
+ void resize(int num_entries);
+
+ void reset();
+
+ void insert(PhysRegIndex idx, DynInstPtr &new_inst);
+
+ void setInst(PhysRegIndex idx, DynInstPtr &new_inst)
+ { dependGraph[idx].inst = new_inst; }
+
+ void clearInst(PhysRegIndex idx)
+ { dependGraph[idx].inst = NULL; }
+
+ void remove(PhysRegIndex idx, DynInstPtr &inst_to_remove);
+
+ DynInstPtr pop(PhysRegIndex idx);
+
+ bool empty(PhysRegIndex idx) { return !dependGraph[idx].next; }
+
+ /** Debugging function to dump out the dependency graph.
+ */
+ void dump();
+
+ private:
+ /** Array of linked lists. Each linked list is a list of all the
+ * instructions that depend upon a given register. The actual
+ * register's index is used to index into the graph; ie all
+ * instructions in flight that are dependent upon r34 will be
+ * in the linked list of dependGraph[34].
+ */
+ DepEntry *dependGraph;
+
+ int numEntries;
+
+ // Debug variable, remove when done testing.
+ unsigned memAllocCounter;
+
+ public:
+ uint64_t nodesTraversed;
+ uint64_t nodesRemoved;
+};
+
+template <class DynInstPtr>
+void
+DependencyGraph<DynInstPtr>::resize(int num_entries)
+{
+ numEntries = num_entries;
+ dependGraph = new DepEntry[numEntries];
+}
+
+template <class DynInstPtr>
+void
+DependencyGraph<DynInstPtr>::reset()
+{
+ // Clear the dependency graph
+ DepEntry *curr;
+ DepEntry *prev;
+
+ for (int i = 0; i < numEntries; ++i) {
+ curr = dependGraph[i].next;
+
+ while (curr) {
+ memAllocCounter--;
+
+ prev = curr;
+ curr = prev->next;
+ prev->inst = NULL;
+
+ delete prev;
+ }
+
+ if (dependGraph[i].inst) {
+ dependGraph[i].inst = NULL;
+ }
+
+ dependGraph[i].next = NULL;
+ }
+}
+
+template <class DynInstPtr>
+void
+DependencyGraph<DynInstPtr>::insert(PhysRegIndex idx, DynInstPtr &new_inst)
+{
+ //Add this new, dependent instruction at the head of the dependency
+ //chain.
+
+ // First create the entry that will be added to the head of the
+ // dependency chain.
+ DepEntry *new_entry = new DepEntry;
+ new_entry->next = dependGraph[idx].next;
+ new_entry->inst = new_inst;
+
+ // Then actually add it to the chain.
+ dependGraph[idx].next = new_entry;
+
+ ++memAllocCounter;
+}
+
+
+template <class DynInstPtr>
+void
+DependencyGraph<DynInstPtr>::remove(PhysRegIndex idx,
+ DynInstPtr &inst_to_remove)
+{
+ DepEntry *prev = &dependGraph[idx];
+ DepEntry *curr = dependGraph[idx].next;
+
+ // Make sure curr isn't NULL. Because this instruction is being
+ // removed from a dependency list, it must have been placed there at
+ // an earlier time. The dependency chain should not be empty,
+ // unless the instruction dependent upon it is already ready.
+ if (curr == NULL) {
+ return;
+ }
+
+ nodesRemoved++;
+
+ // Find the instruction to remove within the dependency linked list.
+ while (curr->inst != inst_to_remove) {
+ prev = curr;
+ curr = curr->next;
+ nodesTraversed++;
+
+ assert(curr != NULL);
+ }
+
+ // Now remove this instruction from the list.
+ prev->next = curr->next;
+
+ --memAllocCounter;
+
+ // Could push this off to the destructor of DependencyEntry
+ curr->inst = NULL;
+
+ delete curr;
+}
+
+template <class DynInstPtr>
+DynInstPtr
+DependencyGraph<DynInstPtr>::pop(PhysRegIndex idx)
+{
+ DepEntry *node;
+ node = dependGraph[idx].next;
+ DynInstPtr inst = NULL;
+ if (node) {
+ inst = node->inst;
+ dependGraph[idx].next = node->next;
+ node->inst = NULL;
+ memAllocCounter--;
+ delete node;
+ }
+ return inst;
+}
+
+template <class DynInstPtr>
+void
+DependencyGraph<DynInstPtr>::dump()
+{
+ DepEntry *curr;
+
+ for (int i = 0; i < numEntries; ++i)
+ {
+ curr = &dependGraph[i];
+
+ if (curr->inst) {
+ cprintf("dependGraph[%i]: producer: %#x [sn:%lli] consumer: ",
+ i, curr->inst->readPC(), curr->inst->seqNum);
+ } else {
+ cprintf("dependGraph[%i]: No producer. consumer: ", i);
+ }
+
+ while (curr->next != NULL) {
+ curr = curr->next;
+
+ cprintf("%#x [sn:%lli] ",
+ curr->inst->readPC(), curr->inst->seqNum);
+ }
+
+ cprintf("\n");
+ }
+ cprintf("memAllocCounter: %i\n", memAllocCounter);
+}
+
+#endif // __CPU_O3_DEP_GRAPH_HH__