PassManager.cpp

//===- PassManager.cpp - LLVM Pass Infrastructure Implementation ----------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the LLVM Pass Manager infrastructure.
//
//===----------------------------------------------------------------------===//


#include "llvm/PassManagers.h"
#include "llvm/Assembly/PrintModulePass.h"
#include "llvm/Assembly/Writer.h"
#include "llvm/IR/Module.h"
#include "llvm/PassManager.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/Mutex.h"
#include "llvm/Support/PassNameParser.h"
#include "llvm/Support/Timer.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
#include <map>
using namespace llvm;

// See PassManagers.h for Pass Manager infrastructure overview.

namespace llvm {

//===----------------------------------------------------------------------===//
// Pass debugging information.  Often it is useful to find out what pass is
// running when a crash occurs in a utility.  When this library is compiled with
// debugging on, a command line option (--debug-pass) is enabled that causes the
// pass name to be printed before it executes.
//

// Different debug levels that can be enabled...
enum PassDebugLevel {
  Disabled, Arguments, Structure, Executions, Details
};

static cl::opt<enum PassDebugLevel>
PassDebugging("debug-pass", cl::Hidden,
                  cl::desc("Print PassManager debugging information"),
                  cl::values(
  clEnumVal(Disabled  , "disable debug output"),
  clEnumVal(Arguments , "print pass arguments to pass to 'opt'"),
  clEnumVal(Structure , "print pass structure before run()"),
  clEnumVal(Executions, "print pass name before it is executed"),
  clEnumVal(Details   , "print pass details when it is executed"),
                             clEnumValEnd));

typedef llvm::cl::list<const llvm::PassInfo *, bool, PassNameParser>
PassOptionList;

// Print IR out before/after specified passes.
static PassOptionList
PrintBefore("print-before",
            llvm::cl::desc("Print IR before specified passes"),
            cl::Hidden);

static PassOptionList
PrintAfter("print-after",
           llvm::cl::desc("Print IR after specified passes"),
           cl::Hidden);

static cl::opt<bool>
PrintBeforeAll("print-before-all",
               llvm::cl::desc("Print IR before each pass"),
               cl::init(false));
static cl::opt<bool>
PrintAfterAll("print-after-all",
              llvm::cl::desc("Print IR after each pass"),
              cl::init(false));

/// This is a helper to determine whether to print IR before or
/// after a pass.

static bool ShouldPrintBeforeOrAfterPass(const PassInfo *PI,
                                         PassOptionList &PassesToPrint) {
  for (unsigned i = 0, ie = PassesToPrint.size(); i < ie; ++i) {
    const llvm::PassInfo *PassInf = PassesToPrint[i];
    if (PassInf)
      if (PassInf->getPassArgument() == PI->getPassArgument()) {
        return true;
      }
  }
  return false;
}

/// This is a utility to check whether a pass should have IR dumped
/// before it.
static bool ShouldPrintBeforePass(const PassInfo *PI) {
  return PrintBeforeAll || ShouldPrintBeforeOrAfterPass(PI, PrintBefore);
}

/// This is a utility to check whether a pass should have IR dumped
/// after it.
static bool ShouldPrintAfterPass(const PassInfo *PI) {
  return PrintAfterAll || ShouldPrintBeforeOrAfterPass(PI, PrintAfter);
}

} // End of llvm namespace

/// isPassDebuggingExecutionsOrMore - Return true if -debug-pass=Executions
/// or higher is specified.
bool PMDataManager::isPassDebuggingExecutionsOrMore() const {
  return PassDebugging >= Executions;
}




void PassManagerPrettyStackEntry::print(raw_ostream &OS) const {
  if (V == 0 && M == 0)
    OS << "Releasing pass '";
  else
    OS << "Running pass '";

  OS << P->getPassName() << "'";

  if (M) {
    OS << " on module '" << M->getModuleIdentifier() << "'.\n";
    return;
  }
  if (V == 0) {
    OS << '\n';
    return;
  }

  OS << " on ";
  if (isa<Function>(V))
    OS << "function";
  else if (isa<BasicBlock>(V))
    OS << "basic block";
  else
    OS << "value";

  OS << " '";
  WriteAsOperand(OS, V, /*PrintTy=*/false, M);
  OS << "'\n";
}


namespace {

//===----------------------------------------------------------------------===//
// BBPassManager
//
/// BBPassManager manages BasicBlockPass. It batches all the
/// pass together and sequence them to process one basic block before
/// processing next basic block.
class BBPassManager : public PMDataManager, public FunctionPass {

public:
  static char ID;
  explicit BBPassManager()
    : PMDataManager(), FunctionPass(ID) {}

  /// 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 runOnFunction(Function &F);

  /// Pass Manager itself does not invalidate any analysis info.
  void getAnalysisUsage(AnalysisUsage &Info) const {
    Info.setPreservesAll();
  }

  bool doInitialization(Module &M);
  bool doInitialization(Function &F);
  bool doFinalization(Module &M);
  bool doFinalization(Function &F);

  virtual PMDataManager *getAsPMDataManager() { return this; }
  virtual Pass *getAsPass() { return this; }

  virtual const char *getPassName() const {
    return "BasicBlock Pass Manager";
  }

  // Print passes managed by this manager
  void dumpPassStructure(unsigned Offset) {
    llvm::dbgs().indent(Offset*2) << "BasicBlockPass Manager\n";
    for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
      BasicBlockPass *BP = getContainedPass(Index);
      BP->dumpPassStructure(Offset + 1);
      dumpLastUses(BP, Offset+1);
    }
  }

  BasicBlockPass *getContainedPass(unsigned N) {
    assert(N < PassVector.size() && "Pass number out of range!");
    BasicBlockPass *BP = static_cast<BasicBlockPass *>(PassVector[N]);
    return BP;