Add RegionPass support.
A RegionPass is executed like a LoopPass but on the regions detected by the
RegionInfo pass instead of the loops detected by the LoopInfo pass.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116905 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/RegionPass.cpp b/lib/Analysis/RegionPass.cpp
new file mode 100644
index 0000000..a4145e1
--- /dev/null
+++ b/lib/Analysis/RegionPass.cpp
@@ -0,0 +1,276 @@
+//===- RegionPass.cpp - Region Pass and Region Pass Manager ---------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements RegionPass and RGPassManager. All region optimization
+// and transformation passes are derived from RegionPass. RGPassManager is
+// responsible for managing RegionPasses.
+// most of these codes are COPY from LoopPass.cpp
+//
+//===----------------------------------------------------------------------===//
+#include "llvm/Analysis/RegionPass.h"
+#include "llvm/Analysis/RegionIterator.h"
+#include "llvm/Support/Timer.h"
+
+#define DEBUG_TYPE "regionpassmgr"
+#include "llvm/Support/Debug.h"
+using namespace llvm;
+
+//===----------------------------------------------------------------------===//
+// RGPassManager
+//
+
+char RGPassManager::ID = 0;
+
+RGPassManager::RGPassManager(int Depth)
+ : FunctionPass(ID), PMDataManager(Depth) {
+ skipThisRegion = false;
+ redoThisRegion = false;
+ RI = NULL;
+ CurrentRegion = NULL;
+}
+
+// Recurse through all subregions and all regions into RQ.
+static void addRegionIntoQueue(Region *R, std::deque<Region *> &RQ) {
+ RQ.push_back(R);
+ for (Region::iterator I = R->begin(), E = R->end(); I != E; ++I)
+ addRegionIntoQueue(*I, RQ);
+}
+
+/// Pass Manager itself does not invalidate any analysis info.
+void RGPassManager::getAnalysisUsage(AnalysisUsage &Info) const {
+ Info.addRequired<RegionInfo>();
+ 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 RGPassManager::runOnFunction(Function &F) {
+ RI = &getAnalysis<RegionInfo>();
+ bool Changed = false;
+
+ // Collect inherited analysis from Module level pass manager.
+ populateInheritedAnalysis(TPM->activeStack);
+
+ addRegionIntoQueue(RI->getTopLevelRegion(), RQ);
+
+ if (RQ.empty()) // No regions, skip calling finalizers
+ return false;
+
+ // Initialization
+ for (std::deque<Region *>::const_iterator I = RQ.begin(), E = RQ.end();
+ I != E; ++I) {
+ Region *R = *I;
+ for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
+ RegionPass *RP = (RegionPass *)getContainedPass(Index);
+ Changed |= RP->doInitialization(R, *this);
+ }
+ }
+
+ // Walk Regions
+ while (!RQ.empty()) {
+
+ CurrentRegion = RQ.back();
+ skipThisRegion = false;
+ redoThisRegion = false;
+
+ // Run all passes on the current Region.
+ for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
+ RegionPass *P = (RegionPass*)getContainedPass(Index);
+
+ dumpPassInfo(P, EXECUTION_MSG, ON_REGION_MSG,
+ CurrentRegion->getNameStr());
+ dumpRequiredSet(P);
+
+ initializeAnalysisImpl(P);
+
+ {
+ PassManagerPrettyStackEntry X(P, *CurrentRegion->getEntry());
+
+ TimeRegion PassTimer(getPassTimer(P));
+ Changed |= P->runOnRegion(CurrentRegion, *this);
+ }
+
+ if (Changed)
+ dumpPassInfo(P, MODIFICATION_MSG, ON_REGION_MSG,
+ skipThisRegion ? "<deleted>" :
+ CurrentRegion->getNameStr());
+ dumpPreservedSet(P);
+
+ if (!skipThisRegion) {
+ // Manually check that this region is still healthy. This is done
+ // instead of relying on RegionInfo::verifyRegion since RegionInfo
+ // is a function pass and it's really expensive to verify every
+ // Region in the function every time. That level of checking can be
+ // enabled with the -verify-region-info option.
+ {
+ TimeRegion PassTimer(getPassTimer(P));
+ CurrentRegion->verifyRegion();
+ }
+
+ // Then call the regular verifyAnalysis functions.
+ verifyPreservedAnalysis(P);
+ }
+
+ removeNotPreservedAnalysis(P);
+ recordAvailableAnalysis(P);
+ removeDeadPasses(P,
+ skipThisRegion ? "<deleted>" :
+ CurrentRegion->getNameStr(),
+ ON_REGION_MSG);
+
+ if (skipThisRegion)
+ // Do not run other passes on this region.
+ break;
+ }
+
+ // If the region was deleted, release all the region passes. This frees up
+ // some memory, and avoids trouble with the pass manager trying to call
+ // verifyAnalysis on them.
+ if (skipThisRegion)
+ for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
+ Pass *P = getContainedPass(Index);
+ freePass(P, "<deleted>", ON_REGION_MSG);
+ }
+
+ // Pop the region from queue after running all passes.
+ RQ.pop_back();
+
+ if (redoThisRegion)
+ RQ.push_back(CurrentRegion);
+
+ // Free all region nodes created in region passes.
+ RI->clearNodeCache();
+ }
+
+ // Finalization
+ for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
+ RegionPass *P = (RegionPass*)getContainedPass(Index);
+ Changed |= P->doFinalization();
+ }
+
+ // Print the region tree after all pass.
+ DEBUG(
+ dbgs() << "\nRegion tree of function " << F.getName()
+ << " after all region Pass:\n";
+ RI->dump();
+ dbgs() << "\n";
+ );
+
+ return Changed;
+}
+
+/// Print passes managed by this manager
+void RGPassManager::dumpPassStructure(unsigned Offset) {
+ errs().indent(Offset*2) << "Region Pass Manager\n";
+ for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
+ Pass *P = getContainedPass(Index);
+ P->dumpPassStructure(Offset + 1);
+ dumpLastUses(P, Offset+1);
+ }
+}
+
+namespace {
+//===----------------------------------------------------------------------===//
+// PrintRegionPass
+class PrintRegionPass : public RegionPass {
+private:
+ std::string Banner;
+ raw_ostream &Out; // raw_ostream to print on.
+
+public:
+ static char ID;
+ PrintRegionPass() : RegionPass(ID), Out(dbgs()) {}
+ PrintRegionPass(const std::string &B, raw_ostream &o)
+ : RegionPass(ID), Banner(B), Out(o) {}
+
+ virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+ AU.setPreservesAll();
+ }
+
+ virtual bool runOnRegion(Region *R, RGPassManager &RGM) {
+ Out << Banner;
+ for (Region::block_iterator I = R->block_begin(), E = R->block_end();
+ I != E; ++I)
+ (*I)->getEntry()->print(Out);
+
+ return false;
+ }
+};
+
+char PrintRegionPass::ID = 0;
+} //end anonymous namespace
+
+//===----------------------------------------------------------------------===//
+// RegionPass
+
+// Check if this pass is suitable for the current RGPassManager, if
+// available. This pass P is not suitable for a RGPassManager if P
+// is not preserving higher level analysis info used by other
+// RGPassManager passes. In such case, pop RGPassManager from the
+// stack. This will force assignPassManager() to create new
+// LPPassManger as expected.
+void RegionPass::preparePassManager(PMStack &PMS) {
+
+ // Find RGPassManager
+ while (!PMS.empty() &&
+ PMS.top()->getPassManagerType() > PMT_RegionPassManager)
+ 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 RGPassManager.
+ if (PMS.top()->getPassManagerType() == PMT_RegionPassManager &&
+ !PMS.top()->preserveHigherLevelAnalysis(this))
+ PMS.pop();
+}
+
+/// Assign pass manager to manage this pass.
+void RegionPass::assignPassManager(PMStack &PMS,
+ PassManagerType PreferredType) {
+ // Find RGPassManager
+ while (!PMS.empty() &&
+ PMS.top()->getPassManagerType() > PMT_RegionPassManager)
+ PMS.pop();
+
+ RGPassManager *RGPM;
+
+ // Create new Region Pass Manager if it does not exist.
+ if (PMS.top()->getPassManagerType() == PMT_RegionPassManager)
+ RGPM = (RGPassManager*)PMS.top();
+ else {
+
+ assert (!PMS.empty() && "Unable to create Region Pass Manager");
+ PMDataManager *PMD = PMS.top();
+
+ // [1] Create new Call Graph Pass Manager
+ RGPM = new RGPassManager(PMD->getDepth() + 1);
+ RGPM->populateInheritedAnalysis(PMS);
+
+ // [2] Set up new manager's top level manager
+ PMTopLevelManager *TPM = PMD->getTopLevelManager();
+ TPM->addIndirectPassManager(RGPM);
+
+ // [3] Assign manager to manage this new manager. This may create
+ // and push new managers into PMS
+ Pass *P = dynamic_cast<Pass *>(RGPM);
+ TPM->schedulePass(P);
+
+ // [4] Push new manager into PMS
+ PMS.push(RGPM);
+ }
+
+ RGPM->add(this);
+}
+
+/// Get the printer pass
+Pass *RegionPass::createPrinterPass(raw_ostream &O,
+ const std::string &Banner) const {
+ return new PrintRegionPass(Banner, O);
+}