X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FAnalysis%2FLoopPass.cpp;h=10e3f297f9c51dd138171a0f40f7cded30f3e638;hb=6c3541d5597033bdb2f26f5ade811b482c32a39a;hp=8d613b09f4234b2cd9955b4e9db212f4fe4ff133;hpb=a5057d02c05efc0ead8787c76a012382ef675b03;p=oota-llvm.git

diff --git a/lib/Analysis/LoopPass.cpp b/lib/Analysis/LoopPass.cpp
index 8d613b09f42..10e3f297f9c 100644
--- a/lib/Analysis/LoopPass.cpp
+++ b/lib/Analysis/LoopPass.cpp
@@ -2,8 +2,8 @@
 //
 //                     The LLVM Compiler Infrastructure
 //
-// This file was developed by Devang Patel and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
@@ -14,142 +14,396 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Analysis/LoopPass.h"
+#include "llvm/DebugInfoProbe.h"
+#include "llvm/Assembly/PrintModulePass.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/ManagedStatic.h"
+#include "llvm/Support/Timer.h"
 using namespace llvm;
 
+namespace {
+
+/// PrintLoopPass - Print a Function corresponding to a Loop.
+///
+class PrintLoopPass : public LoopPass {
+private:
+  std::string Banner;
+  raw_ostream &Out;       // raw_ostream to print on.
+
+public:
+  static char ID;
+  PrintLoopPass(const std::string &B, raw_ostream &o)
+      : LoopPass(ID), Banner(B), Out(o) {}
+
+  virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+    AU.setPreservesAll();
+  }
+
+  bool runOnLoop(Loop *L, LPPassManager &) {
+    Out << Banner;
+    for (Loop::block_iterator b = L->block_begin(), be = L->block_end();
+         b != be;
+         ++b) {
+      (*b)->print(Out);
+    }
+    return false;
+  }
+};
+
+char PrintLoopPass::ID = 0;
+}
+
+//===----------------------------------------------------------------------===//
+// DebugInfoProbe
+
+static DebugInfoProbeInfo *TheDebugProbe;
+static void createDebugInfoProbe() {
+  if (TheDebugProbe) return;
+      
+  // Constructed the first time this is called. This guarantees that the 
+  // object will be constructed, if -enable-debug-info-probe is set, 
+  // before static globals, thus it will be destroyed before them.
+  static ManagedStatic<DebugInfoProbeInfo> DIP;
+  TheDebugProbe = &*DIP;
+}
+
 //===----------------------------------------------------------------------===//
 // LPPassManager
 //
-/// LPPassManager manages FPPassManagers and CalLGraphSCCPasses.
 
-LPPassManager::LPPassManager(int Depth) : PMDataManager(Depth) { 
+char LPPassManager::ID = 0;
+
+LPPassManager::LPPassManager(int Depth) 
+  : FunctionPass(ID), PMDataManager(Depth) { 
   skipThisLoop = false;
   redoThisLoop = false;
+  LI = NULL;
+  CurrentLoop = NULL;
 }
 
-/// Delete loop from the loop queue. This is used by Loop pass to inform
-/// Loop Pass Manager that it should skip rest of the passes for this loop.
+/// Delete loop from the loop queue and loop hierarchy (LoopInfo). 
 void LPPassManager::deleteLoopFromQueue(Loop *L) {
-  // Do not pop loop from LQ here. It will be done by runOnFunction while loop.
-  skipThisLoop = true;
+
+  if (Loop *ParentLoop = L->getParentLoop()) { // Not a top-level loop.
+    // Reparent all of the blocks in this loop.  Since BBLoop had a parent,
+    // they are now all in it.
+    for (Loop::block_iterator I = L->block_begin(), E = L->block_end(); 
+         I != E; ++I)
+      if (LI->getLoopFor(*I) == L)    // Don't change blocks in subloops.
+        LI->changeLoopFor(*I, ParentLoop);
+    
+    // Remove the loop from its parent loop.
+    for (Loop::iterator I = ParentLoop->begin(), E = ParentLoop->end();;
+         ++I) {
+      assert(I != E && "Couldn't find loop");
+      if (*I == L) {
+        ParentLoop->removeChildLoop(I);
+        break;
+      }
+    }
+    
+    // Move all subloops into the parent loop.
+    while (!L->empty())
+      ParentLoop->addChildLoop(L->removeChildLoop(L->end()-1));
+  } else {
+    // Reparent all of the blocks in this loop.  Since BBLoop had no parent,
+    // they no longer in a loop at all.
+    
+    for (unsigned i = 0; i != L->getBlocks().size(); ++i) {
+      // Don't change blocks in subloops.
+      if (LI->getLoopFor(L->getBlocks()[i]) == L) {
+        LI->removeBlock(L->getBlocks()[i]);
+        --i;
+      }
+    }
+
+    // Remove the loop from the top-level LoopInfo object.
+    for (LoopInfo::iterator I = LI->begin(), E = LI->end();; ++I) {
+      assert(I != E && "Couldn't find loop");
+      if (*I == L) {
+        LI->removeLoop(I);
+        break;
+      }
+    }
+
+    // Move all of the subloops to the top-level.
+    while (!L->empty())
+      LI->addTopLevelLoop(L->removeChildLoop(L->end()-1));
+  }
+
+  delete L;
+
+  // If L is current loop then skip rest of the passes and let
+  // runOnFunction remove L from LQ. Otherwise, remove L from LQ now
+  // and continue applying other passes on CurrentLoop.
+  if (CurrentLoop == L) {
+    skipThisLoop = true;
+    return;
+  }
+
+  for (std::deque<Loop *>::iterator I = LQ.begin(),
+         E = LQ.end(); I != E; ++I) {
+    if (*I == L) {
+      LQ.erase(I);
+      break;
+    }
+  }
+}
+
+// Inset loop into loop nest (LoopInfo) and loop queue (LQ).
+void LPPassManager::insertLoop(Loop *L, Loop *ParentLoop) {
+
+  assert (CurrentLoop != L && "Cannot insert CurrentLoop");
+
+  // Insert into loop nest
+  if (ParentLoop)
+    ParentLoop->addChildLoop(L);
+  else
+    LI->addTopLevelLoop(L);
+
+  insertLoopIntoQueue(L);
+}
+
+void LPPassManager::insertLoopIntoQueue(Loop *L) {
+  // Insert L into loop queue
+  if (L == CurrentLoop) 
+    redoLoop(L);
+  else if (!L->getParentLoop())
+    // This is top level loop. 
+    LQ.push_front(L);
+  else {
+    // Insert L after the parent loop.
+    for (std::deque<Loop *>::iterator I = LQ.begin(),
+           E = LQ.end(); I != E; ++I) {
+      if (*I == L->getParentLoop()) {
+        // deque does not support insert after.
+        ++I;
+        LQ.insert(I, 1, L);
+        break;
+      }
+    }
+  }
 }
 
 // Reoptimize this loop. LPPassManager will re-insert this loop into the
 // queue. This allows LoopPass to change loop nest for the loop. This
 // utility may send LPPassManager into infinite loops so use caution.
 void LPPassManager::redoLoop(Loop *L) {
+  assert (CurrentLoop == L && "Can redo only CurrentLoop");
   redoThisLoop = true;
 }
 
+/// cloneBasicBlockSimpleAnalysis - Invoke cloneBasicBlockAnalysis hook for
+/// all loop passes.
+void LPPassManager::cloneBasicBlockSimpleAnalysis(BasicBlock *From, 
+                                                  BasicBlock *To, Loop *L) {
+  for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {  
+    LoopPass *LP = getContainedPass(Index);
+    LP->cloneBasicBlockAnalysis(From, To, L);
+  }
+}
+
+/// deleteSimpleAnalysisValue - Invoke deleteAnalysisValue hook for all passes.
+void LPPassManager::deleteSimpleAnalysisValue(Value *V, Loop *L) {
+  if (BasicBlock *BB = dyn_cast<BasicBlock>(V)) {
+    for (BasicBlock::iterator BI = BB->begin(), BE = BB->end(); BI != BE; 
+         ++BI) {
+      Instruction &I = *BI;
+      deleteSimpleAnalysisValue(&I, L);
+    }
+  }
+  for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {  
+    LoopPass *LP = getContainedPass(Index);
+    LP->deleteAnalysisValue(V, L);
+  }
+}
+
+
 // Recurse through all subloops and all loops  into LQ.
 static void addLoopIntoQueue(Loop *L, std::deque<Loop *> &LQ) {
+  LQ.push_back(L);
   for (Loop::iterator I = L->begin(), E = L->end(); I != E; ++I)
     addLoopIntoQueue(*I, LQ);
-  LQ.push_back(L);
+}
+
+/// Pass Manager itself does not invalidate any analysis info.
+void LPPassManager::getAnalysisUsage(AnalysisUsage &Info) const {
+  // LPPassManager needs LoopInfo. In the long term LoopInfo class will 
+  // become part of LPPassManager.
+  Info.addRequired<LoopInfo>();
+  Info.setPreservesAll();
 }
 
 /// run - Execute all of the passes scheduled for execution.  Keep track of
 /// whether any of the passes modifies the function, and if so, return true.
 bool LPPassManager::runOnFunction(Function &F) {
-  LoopInfo &LI = getAnalysis<LoopInfo>();
+  LI = &getAnalysis<LoopInfo>();
   bool Changed = false;
+  createDebugInfoProbe();
+
+  // Collect inherited analysis from Module level pass manager.
+  populateInheritedAnalysis(TPM->activeStack);
 
   // Populate Loop Queue
-  for (LoopInfo::iterator I = LI.begin(), E = LI.end(); I != E; ++I)
+  for (LoopInfo::iterator I = LI->begin(), E = LI->end(); I != E; ++I)
     addLoopIntoQueue(*I, LQ);
 
+  if (LQ.empty()) // No loops, skip calling finalizers
+    return false;
+
   // Initialization
   for (std::deque<Loop *>::const_iterator I = LQ.begin(), E = LQ.end();
        I != E; ++I) {
     Loop *L = *I;
     for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {  
-      Pass *P = getContainedPass(Index);
-      LoopPass *LP = dynamic_cast<LoopPass *>(P);
-      if (LP)
-        Changed |= LP->doInitialization(L, *this);
+      LoopPass *P = getContainedPass(Index);
+      Changed |= P->doInitialization(L, *this);
     }
   }
 
   // Walk Loops
   while (!LQ.empty()) {
       
-    Loop *L  = LQ.back();
+    CurrentLoop  = LQ.back();
     skipThisLoop = false;
     redoThisLoop = false;
 
-    // Run all passes on current SCC
+    // Run all passes on the current Loop.
     for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {  
-        
-      Pass *P = getContainedPass(Index);
-      AnalysisUsage AnUsage;
-      P->getAnalysisUsage(AnUsage);
-
-      dumpPassInfo(P, EXECUTION_MSG, ON_LOOP_MSG, "");
-      dumpAnalysisSetInfo("Required", P, AnUsage.getRequiredSet());
+      LoopPass *P = getContainedPass(Index);
+      dumpPassInfo(P, EXECUTION_MSG, ON_LOOP_MSG,
+                   CurrentLoop->getHeader()->getName());
+      dumpRequiredSet(P);
 
       initializeAnalysisImpl(P);
+      if (TheDebugProbe)
+        TheDebugProbe->initialize(P, F);
+      {
+        PassManagerPrettyStackEntry X(P, *CurrentLoop->getHeader());
+        TimeRegion PassTimer(getPassTimer(P));
 
-      StartPassTimer(P);
-      LoopPass *LP = dynamic_cast<LoopPass *>(P);
-      assert (LP && "Invalid LPPassManager member");
-      LP->runOnLoop(L, *this);
-      StopPassTimer(P);
+        Changed |= P->runOnLoop(CurrentLoop, *this);
+      }
+      if (TheDebugProbe)
+        TheDebugProbe->finalize(P, F);
 
       if (Changed)
-        dumpPassInfo(P, MODIFICATION_MSG, ON_LOOP_MSG, "");
-      dumpAnalysisSetInfo("Preserved", P, AnUsage.getPreservedSet());
-      
+        dumpPassInfo(P, MODIFICATION_MSG, ON_LOOP_MSG,
+                     skipThisLoop ? "<deleted>" :
+                                    CurrentLoop->getHeader()->getName());
+      dumpPreservedSet(P);
+
+      if (!skipThisLoop) {
+        // Manually check that this loop is still healthy. This is done
+        // instead of relying on LoopInfo::verifyLoop since LoopInfo
+        // is a function pass and it's really expensive to verify every
+        // loop in the function every time. That level of checking can be
+        // enabled with the -verify-loop-info option.
+        {
+          TimeRegion PassTimer(getPassTimer(LI));
+          CurrentLoop->verifyLoop();
+        }
+
+        // Then call the regular verifyAnalysis functions.
+        verifyPreservedAnalysis(P);
+      }
+
       removeNotPreservedAnalysis(P);
       recordAvailableAnalysis(P);
-      removeDeadPasses(P, "", ON_LOOP_MSG);
+      removeDeadPasses(P,
+                       skipThisLoop ? "<deleted>" :
+                                      CurrentLoop->getHeader()->getName(),
+                       ON_LOOP_MSG);
 
       if (skipThisLoop)
         // Do not run other passes on this loop.
         break;
     }
     
+    // If the loop was deleted, release all the loop passes. This frees up
+    // some memory, and avoids trouble with the pass manager trying to call
+    // verifyAnalysis on them.
+    if (skipThisLoop)
+      for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {  
+        Pass *P = getContainedPass(Index);
+        freePass(P, "<deleted>", ON_LOOP_MSG);
+      }
+
     // Pop the loop from queue after running all passes.
     LQ.pop_back();
     
     if (redoThisLoop)
-      LQ.push_back(L);
+      LQ.push_back(CurrentLoop);
   }
   
   // Finalization
   for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
-    Pass *P = getContainedPass(Index);
-    LoopPass *LP = dynamic_cast <LoopPass *>(P);
-    if (LP)
-      Changed |= LP->doFinalization();
+    LoopPass *P = getContainedPass(Index);
+    Changed |= P->doFinalization();
   }
 
   return Changed;
 }
 
+/// Print passes managed by this manager
+void LPPassManager::dumpPassStructure(unsigned Offset) {
+  errs().indent(Offset*2) << "Loop Pass Manager\n";
+  for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
+    Pass *P = getContainedPass(Index);
+    P->dumpPassStructure(Offset + 1);
+    dumpLastUses(P, Offset+1);
+  }
+}
+
 
 //===----------------------------------------------------------------------===//
 // LoopPass
 
+Pass *LoopPass::createPrinterPass(raw_ostream &O,
+                                  const std::string &Banner) const {
+  return new PrintLoopPass(Banner, O);
+}
+
+// Check if this pass is suitable for the current LPPassManager, if
+// available. This pass P is not suitable for a LPPassManager if P
+// is not preserving higher level analysis info used by other
+// LPPassManager passes. In such case, pop LPPassManager from the
+// stack. This will force assignPassManager() to create new
+// LPPassManger as expected.
+void LoopPass::preparePassManager(PMStack &PMS) {
+
+  // Find LPPassManager 
+  while (!PMS.empty() &&
+         PMS.top()->getPassManagerType() > PMT_LoopPassManager)
+    PMS.pop();
+
+  // If this pass is destroying high level information that is used
+  // by other passes that are managed by LPM then do not insert
+  // this pass in current LPM. Use new LPPassManager.
+  if (PMS.top()->getPassManagerType() == PMT_LoopPassManager &&
+      !PMS.top()->preserveHigherLevelAnalysis(this)) 
+    PMS.pop();
+}
+
 /// Assign pass manager to manage this pass.
 void LoopPass::assignPassManager(PMStack &PMS,
                                  PassManagerType PreferredType) {
   // Find LPPassManager 
-  while (!PMS.empty()) {
-    if (PMS.top()->getPassManagerType() > PMT_LoopPassManager)
-      PMS.pop();
-    else;
-    break;
-  }
-
-  LPPassManager *LPPM = dynamic_cast<LPPassManager *>(PMS.top());
-
-  // Create new Loop Pass Manager if it does not exist. 
-  if (!LPPM) {
+  while (!PMS.empty() &&
+         PMS.top()->getPassManagerType() > PMT_LoopPassManager)
+    PMS.pop();
 
+  LPPassManager *LPPM;
+  if (PMS.top()->getPassManagerType() == PMT_LoopPassManager)
+    LPPM = (LPPassManager*)PMS.top();
+  else {
+    // Create new Loop Pass Manager if it does not exist. 
     assert (!PMS.empty() && "Unable to create Loop Pass Manager");
     PMDataManager *PMD = PMS.top();
 
     // [1] Create new Call Graph Pass Manager
     LPPM = new LPPassManager(PMD->getDepth() + 1);
+    LPPM->populateInheritedAnalysis(PMS);
 
     // [2] Set up new manager's top level manager
     PMTopLevelManager *TPM = PMD->getTopLevelManager();
@@ -157,8 +411,8 @@ void LoopPass::assignPassManager(PMStack &PMS,
 
     // [3] Assign manager to manage this new manager. This may create
     // and push new managers into PMS
-    Pass *P = dynamic_cast<Pass *>(LPPM);
-    P->assignPassManager(PMS);
+    Pass *P = LPPM->getAsPass();
+    TPM->schedulePass(P);
 
     // [4] Push new manager into PMS
     PMS.push(LPPM);
@@ -166,4 +420,3 @@ void LoopPass::assignPassManager(PMStack &PMS,
 
   LPPM->add(this);
 }
-