path: root/include/llvm/PassSupport.h

//===- llvm/PassSupport.h - Pass Support code -------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines stuff that is used to define and "use" Passes.  This file
// is automatically #included by Pass.h, so:
//
//           NO .CPP FILES SHOULD INCLUDE THIS FILE DIRECTLY
//
// Instead, #include Pass.h.
//
// This file defines Pass registration code and classes used for it.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_PASS_SUPPORT_H
#define LLVM_PASS_SUPPORT_H

#include "Pass.h"
#include "llvm/PassRegistry.h"
#include "llvm/InitializePasses.h"
#include "llvm/Support/Atomic.h"
#include <vector>

namespace llvm {

  class PassManagerBase;

//===---------------------------------------------------------------------------
/// PassInfo class - An instance of this class exists for every pass known by
/// the system, and can be obtained from a live Pass by calling its
/// getPassInfo() method.  These objects are set up by the RegisterPass<>
/// template, defined below.
///
class PassInfo {
public:
  typedef Pass* (*NormalCtor_t)();

private:
  const char      *const PassName;     // Nice name for Pass
  const char      *const PassArgument; // Command Line argument to run this pass
  const void *PassID;      
  const bool IsCFGOnlyPass;            // Pass only looks at the CFG.
  const bool IsAnalysis;               // True if an analysis pass.
  const bool IsAnalysisGroup;          // True if an analysis group.
  std::vector<const PassInfo*> ItfImpl;// Interfaces implemented by this pass

  NormalCtor_t NormalCtor;

public:
  /// PassInfo ctor - Do not call this directly, this should only be invoked
  /// through RegisterPass.
  PassInfo(const char *name, const char *arg, const void *pi,
           NormalCtor_t normal, bool isCFGOnly, bool is_analysis)
    : PassName(name), PassArgument(arg), PassID(pi), 
      IsCFGOnlyPass(isCFGOnly), 
      IsAnalysis(is_analysis), IsAnalysisGroup(false), NormalCtor(normal) { }
  /// PassInfo ctor - Do not call this directly, this should only be invoked
  /// through RegisterPass. This version is for use by analysis groups; it
  /// does not auto-register the pass.
  PassInfo(const char *name, const void *pi)
    : PassName(name), PassArgument(""), PassID(pi), 
      IsCFGOnlyPass(false), 
      IsAnalysis(false), IsAnalysisGroup(true), NormalCtor(0) { }

  /// getPassName - Return the friendly name for the pass, never returns null
  ///
  const char *getPassName() const { return PassName; }

  /// getPassArgument - Return the command line option that may be passed to
  /// 'opt' that will cause this pass to be run.  This will return null if there
  /// is no argument.
  ///
  const char *getPassArgument() const { return PassArgument; }

  /// getTypeInfo - Return the id object for the pass...
  /// TODO : Rename
  const void *getTypeInfo() const { return PassID; }

  /// Return true if this PassID implements the specified ID pointer.
  bool isPassID(const void *IDPtr) const {
    return PassID == IDPtr;
  }
  
  /// isAnalysisGroup - Return true if this is an analysis group, not a normal
  /// pass.
  ///
  bool isAnalysisGroup() const { return IsAnalysisGroup; }
  bool isAnalysis() const { return IsAnalysis; }

  /// isCFGOnlyPass - return true if this pass only looks at the CFG for the
  /// function.
  bool isCFGOnlyPass() const { return IsCFGOnlyPass; }
  
  /// getNormalCtor - Return a pointer to a function, that when called, creates
  /// an instance of the pass and returns it.  This pointer may be null if there
  /// is no default constructor for the pass.
  ///
  NormalCtor_t getNormalCtor() const {
    return NormalCtor;
  }
  void setNormalCtor(NormalCtor_t Ctor) {
    NormalCtor = Ctor;
  }

  /// createPass() - Use this method to create an instance of this pass.
  Pass *createPass() const;

  /// addInterfaceImplemented - This method is called when this pass is
  /// registered as a member of an analysis group with the RegisterAnalysisGroup
  /// template.
  ///
  void addInterfaceImplemented(const PassInfo *ItfPI) {
    ItfImpl.push_back(ItfPI);
  }

  /// getInterfacesImplemented - Return a list of all of the analysis group
  /// interfaces implemented by this pass.
  ///
  const std::vector<const PassInfo*> &getInterfacesImplemented() const {
    return ItfImpl;
  }

private:
  void operator=(const PassInfo &); // do not implement
  PassInfo(const PassInfo &);       // do not implement
};

#define CALL_ONCE_INITIALIZATION(function) \
  static volatile sys::cas_flag initialized = 0; \
  sys::cas_flag old_val = sys::CompareAndSwap(&initialized, 1, 0); \
  if (old_val == 0) { \
    function(Registry); \
    sys::MemoryFence(); \
    initialized = 2; \
  } else { \
    sys::cas_flag tmp = initialized; \
    sys::MemoryFence(); \
    while (tmp != 2) { \
      tmp = initialized; \
      sys::MemoryFence(); \
    } \
  }

#define INITIALIZE_PASS(passName, arg, name, cfg, analysis) \
  static void* initialize##passName##PassOnce(PassRegistry &Registry) { \
    PassInfo *PI = new PassInfo(name, arg, & passName ::ID, \
      PassInfo::NormalCtor_t(callDefaultCtor< passName >), cfg, analysis); \
    Registry.registerPass(*PI, true); \
    return PI; \
  } \
  void llvm::initialize##passName##Pass(PassRegistry &Registry) { \
    CALL_ONCE_INITIALIZATION(initialize##passName##PassOnce) \
  }

#define INITIALIZE_PASS_BEGIN(passName, arg, name, cfg, analysis) \
  static void* initialize##passName##PassOnce(PassRegistry &Registry) {

#define INITIALIZE_PASS_DEPENDENCY(depName) \
    initialize##depName##Pass(Registry);
#define INITIALIZE_AG_DEPENDENCY(depName) \
    initialize##depName##AnalysisGroup(Registry);

#define INITIALIZE_PASS_END(passName, arg, name, cfg, analysis) \
    PassInfo *PI = new PassInfo(name, arg, & passName ::ID, \
      PassInfo::NormalCtor_t(callDefaultCtor< passName >), cfg, analysis); \
    Registry.registerPass(*PI, true); \
    return PI; \
  } \
  void llvm::initialize##passName##Pass(PassRegistry &Registry) { \
    CALL_ONCE_INITIALIZATION(initialize##passName##PassOnce) \
  }

template<typename PassName>
Pass *callDefaultCtor() { return new PassName(); }

//===---------------------------------------------------------------------------
/// RegisterPass<t> template - This template class is used to notify the system
/// that a Pass is available for use, and registers it into the internal
/// database maintained by the PassManager.  Unless this template is used, opt,
/// for example will not be able to see the pass and attempts to create the pass
/// will fail. This template is used in the follow manner (at global scope, in
/// your .cpp file):
///
/// static RegisterPass<YourPassClassName> tmp("passopt", "My Pass Name");
///
/// This statement will cause your pass to be created by calling the default
/// constructor exposed by the pass.  If you have a different constructor that
/// must be called, create a global constructor function (which takes the
/// arguments you need and returns a Pass*) and register your pass like this:
///
/// static RegisterPass<PassClassName> tmp("passopt", "My Name");
///
template<typename passName>
struct RegisterPass : public PassInfo {

  // Register Pass using default constructor...
  RegisterPass(const char *PassArg, const char *Name, bool CFGOnly = false,
               bool is_analysis = false)
    : PassInfo(Name, PassArg, &passName::ID,
               PassInfo::NormalCtor_t(callDefaultCtor<passName>),
               CFGOnly, is_analysis) {
    PassRegistry::getPassRegistry()->registerPass(*this);
  }
};

  /// Unique identifiers for the default standard passes.  The addresses of
  /// these symbols are used to uniquely identify passes from the default list.
  namespace DefaultStandardPasses {
    extern unsigned char AggressiveDCEID;
    extern unsigned char ArgumentPromotionID;
    extern unsigned char BasicAliasAnalysisID;
    extern unsigned char CFGSimplificationID;
    extern unsigned char ConstantMergeID;
    extern unsigned char CorrelatedValuePropagationID;
    extern unsigned char DeadArgEliminationID;
    extern unsigned char DeadStoreEliminationID;
    extern unsigned char DeadTypeEliminationID;
    extern unsigned char EarlyCSEID;
    extern unsigned char FunctionAttrsID;
    extern unsigned char FunctionInliningID;
    extern unsigned char GVNID;
    extern unsigned char GlobalDCEID;
    extern unsigned char GlobalOptimizerID;
    extern unsigned char GlobalsModRefID;
    extern unsigned char IPSCCPID;
    extern unsigned char IndVarSimplifyID;
    extern unsigned char InlinerPlaceholderID;
    extern unsigned char InstructionCombiningID;
    extern unsigned char JumpThreadingID;
    extern unsigned char LICMID;
    extern unsigned char LoopDeletionID;
    extern unsigned char LoopIdiomID;
    extern unsigned char LoopRotateID;
    extern unsigned char LoopUnrollID;
    extern unsigned char LoopUnswitchID;
    extern unsigned char MemCpyOptID;
    extern unsigned char PruneEHID;
    extern unsigned char ReassociateID;
    extern unsigned char SCCPID;
    extern unsigned char ScalarReplAggregatesID;
    extern unsigned char SimplifyLibCallsID;
    extern unsigned char StripDeadPrototypesID;
    extern unsigned char TailCallEliminationID;
    extern unsigned char TypeBasedAliasAnalysisID;
  }


class RegisterStandardPass;
/// RegisterStandardPass - Registers a pass as a member of a standard set.  
class StandardPass {
  friend class RegisterStandardPassLists;
  public:
  /// Predefined standard sets of passes
  enum StandardSet {
    AliasAnalysis,
    Function,
    Module,
    LTO
  };
  /// Flags to specify whether a pass should be enabled.  Passes registered
  /// with the standard sets may specify a minimum optimization level and one
  /// or more flags that must be set when constructing the set for the pass to
  /// be used.
  enum OptimizationFlags {
    /// Optimize for size was requested.
    OptimizeSize = 1<<0,
    /// Allow passes which may make global module changes.
    UnitAtATime = 1<<1,
    /// UnrollLoops - Allow loop unrolling.
    UnrollLoops = 1<<2,
    /// Allow library calls to be simplified.
    SimplifyLibCalls = 1<<3,
    /// Whether the module may have code using exceptions.
    HaveExceptions = 1<<4,
    // Run an inliner pass as part of this set.
    RunInliner = 1<<5
  };
  enum OptimizationFlagComponents {
    /// The low bits are used to store the optimization level.  When requesting
    /// passes, this should store the requested optimisation level.  When
    /// setting passes, this should set the minimum optimization level at which
    /// the pass will run.
    OptimizationLevel