//
// 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.
//
//===----------------------------------------------------------------------===//
//
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/LoopPass.h"
-#include <queue>
+#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;
-//===----------------------------------------------------------------------===//
-// LoopQueue
+namespace {
-namespace llvm {
+/// PrintLoopPass - Print a Function corresponding to a Loop.
+///
+class PrintLoopPass : public LoopPass {
+private:
+ std::string Banner;
+ raw_ostream &Out; // raw_ostream to print on.
-// Compare Two loops based on their depth in loop nest.
-class LoopCompare {
public:
- bool operator()( Loop *L1, Loop *L2) const {
- return L1->getLoopDepth() > L2->getLoopDepth();
+ 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();
}
-};
-// Loop queue used by Loop Pass Manager. This is a wrapper class
-// that hides implemenation detail (use of priority_queue) inside .cpp file.
-class LoopQueue {
-public:
- inline void push(Loop *L) { LPQ.push(L); }
- inline void pop() { LPQ.pop(); }
- inline Loop *top() { return LPQ.top(); }
- inline bool empty() { return LPQ.empty(); }
-private:
- std::priority_queue<Loop *, std::vector<Loop *>, LoopCompare> LPQ;
+ 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;
+ }
};
-} // End of LLVM namespace
+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;
- LQ = new LoopQueue();
+ LI = NULL;
+ CurrentLoop = NULL;
}
-LPPassManager::~LPPassManager() {
- delete LQ;
+/// Delete loop from the loop queue and loop hierarchy (LoopInfo).
+void LPPassManager::deleteLoopFromQueue(Loop *L) {
+
+ 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;
+ }
+ }
}
-/// 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.
-void LPPassManager::deleteLoopFromQueue(Loop *L) {
- // Do not pop loop from LQ here. It will be done by runOnFunction while loop.
- skipThisLoop = true;
+// 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, LoopQueue *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(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);
- std::string Msg1 = "Executing Pass '";
- std::string Msg3 = "' Made Modification '";
+ 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) {
+ LoopPass *P = getContainedPass(Index);
+ Changed |= P->doInitialization(L, *this);
+ }
+ }
// Walk Loops
- while (!LQ->empty()) {
+ while (!LQ.empty()) {
- Loop *L = LQ->top();
+ 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);
-
- std::string Msg2 = "' on Loop ...\n'";
- dumpPassInfo(P, Msg1, Msg2);
- 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, Msg3, Msg2);
- 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, Msg2);
+ 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();
+ LQ.pop_back();
if (redoThisLoop)
- LQ->push(L);
+ LQ.push_back(CurrentLoop);
+ }
+
+ // Finalization
+ for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
+ 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();
// [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);
LPPM->add(this);
}
-