Flesh out a bunch more code, print allocations that are poolable.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@2031 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/IPO/OldPoolAllocate.cpp

@@ -9,25 +9,164 @@
 #include "llvm/Transforms/IPO/PoolAllocate.h"
 #include "llvm/Analysis/DataStructure.h"
 #include "llvm/Pass.h"
+#include "llvm/Module.h"
+#include "llvm/Function.h"
+#include "llvm/iMemory.h"
+#include <algorithm>
 
-
+// Define the pass class that we implement...
 namespace {
-  struct PoolAllocate : public Pass {
-    bool run(Module *M) {
-      DataStructure &DS = getAnalysis<DataStructure>();
-      return false;
+  class PoolAllocate : public Pass {
+    // PoolTy - The type of a scalar value that contains a pool pointer.
+    PointerType *PoolTy;
+  public:
+
+    PoolAllocate() {
+      // Initialize the PoolTy instance variable, since the type never changes.
+      vector<const Type*> PoolElements;
+      PoolElements.push_back(PointerType::get(Type::SByteTy));
+      PoolElements.push_back(Type::UIntTy);
+      PoolTy = PointerType::get(StructType::get(PoolElements));
+      // PoolTy = { sbyte*, uint }*
+
+      CurModule = 0; DS = 0;
+      PoolInit = PoolDestroy = PoolAlloc = PoolFree = 0;
     }
 
-    // getAnalysisUsageInfo - This function works on the call graph of a module.
-    // It is capable of updating the call graph to reflect the new state of the
-    // module.
+    bool run(Module *M);
+
+    // getAnalysisUsageInfo - This function requires data structure information
+    // to be able to see what is pool allocatable.
     //
     virtual void getAnalysisUsageInfo(Pass::AnalysisSet &Required,
-                                      Pass::AnalysisSet &Destroyed,
-                                      Pass::AnalysisSet &Provided) {
+                                      Pass::AnalysisSet &,Pass::AnalysisSet &) {
       Required.push_back(DataStructure::ID);
     }
+
+  private:
+    // CurModule - The module being processed.
+    Module *CurModule;
+
+    // DS - The data structure graph for the module being processed.
+    DataStructure *DS;
+
+    // Prototypes that we add to support pool allocation...
+    Function *PoolInit, *PoolDestroy, *PoolAlloc, *PoolFree;
+
+    // addPoolPrototypes - Add prototypes for the pool methods to the specified
+    // module and update the Pool* instance variables to point to them.
+    //
+    void addPoolPrototypes(Module *M);
+
+    // processFunction - Convert a function to use pool allocation where
+    // available.
+    //
+    bool processFunction(Function *F);
   };
 }
 
+
+
+// isNotPoolableAlloc - This is a predicate that returns true if the specified 
+// allocation node in a data structure graph is eligable for pool allocation.
+//
+static bool isNotPoolableAlloc(const AllocDSNode *DS) {
+  if (DS->isAllocaNode()) return false;  // Do not pool allocate alloca's.
+
+  MallocInst *MI = cast<MallocInst>(DS->getAllocation());
+  if (MI->isArrayAllocation() && !isa<Constant>(MI->getArraySize()))
+    return false;   // Do not allow variable size allocations...
+
+  return true;
+}
+
+
+// processFunction - Convert a function to use pool allocation where
+// available.
+//
+bool PoolAllocate::processFunction(Function *F) {
+  // Get the closed datastructure graph for the current function... if there are
+  // any allocations in this graph that are not escaping, we need to pool
+  // allocate them here!
+  //
+  FunctionDSGraph &IPGraph = DS->getClosedDSGraph(F);
+
+  // Get all of the allocations that do not escape the current function.  Since
+  // they are still live (they exist in the graph at all), this means we must
+  // have scalar references to these nodes, but the scalars are never returned.
+  // 
+  std::vector<AllocDSNode*> Allocs;
+  IPGraph.getNonEscapingAllocations(Allocs);
+
+  // Filter out allocations that we cannot handle.  Currently, this includes
+  // variable sized array allocations and alloca's (which we do not want to
+  // pool allocate)
+  //
+  Allocs.erase(remove_if(Allocs.begin(), Allocs.end(), isNotPoolableAlloc),
+               Allocs.end());
+
+
+  if (Allocs.empty()) return false;  // Nothing to do.
+
+  // Loop through the value map looking for scalars that refer to nonescaping
+  // allocations.
+  //
+  map<Value*, PointerValSet> &ValMap = IPGraph.getValueMap();
+  vector<pair<Value*, AllocDSNode*> > Scalars;
+
+  for (map<Value*, PointerValSet>::iterator I = ValMap.begin(),
+         E = ValMap.end(); I != E; ++I) {
+    const PointerValSet &PVS = I->second;  // Set of things pointed to by scalar
+    // Check to see if the scalar points to anything that is an allocation...
+    for (unsigned i = 0, e = PVS.size(); i != e; ++i)
+      if (AllocDSNode *Alloc = dyn_cast<AllocDSNode>(PVS[i].Node)) {
+        assert(PVS[i].Index == 0 && "Nonzero not handled yet!");
+        
+        // If the allocation is in the nonescaping set...
+        if (find(Allocs.begin(), Allocs.end(), Alloc) != Allocs.end())
+          // Add it to the list of scalars we have
+          Scalars.push_back(make_pair(I->first, Alloc));
+      }
+  }
+
+  cerr << "In '" << F->getName()
+       << "': Found the following values that point to poolable nodes:\n";
+
+  for (unsigned i = 0, e = Scalars.size(); i != e; ++i)
+    Scalars[i].first->dump();
+  return false;
+}
+
+
+// Prototypes that we add to support pool allocation...
+Function *PoolInit, *PoolDestroy, *PoolAlloc, *PoolFree;
+
+// addPoolPrototypes - Add prototypes for the pool methods to the specified
+// module and update the Pool* instance variables to point to them.
+//
+void PoolAllocate::addPoolPrototypes(Module *M) {
+  //M->getOrCreate...
+
+}
+
+
+bool PoolAllocate::run(Module *M) {
+  addPoolPrototypes(M);
+  CurModule = M;
+  
+  DS = &getAnalysis<DataStructure>();
+  bool Changed = false;
+  for (Module::iterator I = M->begin(); I != M->end(); ++I)
+    if (!(*I)->isExternal())
+      Changed |= processFunction(*I);
+
+  CurModule = 0;
+  DS = 0;
+  return false;
+}
+
+
+// createPoolAllocatePass - Global function to access the functionality of this
+// pass...
+//
 Pass *createPoolAllocatePass() { return new PoolAllocate(); }