-//===- llvm/Pass.h - Base class for XForm Passes -----------------*- C++ -*--=//
+//===- llvm/Pass.h - Base class for Passes ----------------------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
//
// This file defines a base class that indicates that a specified class is a
// transformation pass implementation.
#include <map>
#include <iosfwd>
#include <typeinfo>
+#include <cassert>
+
+namespace llvm {
+
class Value;
class BasicBlock;
class Function;
class Module;
class AnalysisUsage;
class PassInfo;
+class ImmutablePass;
template<class UnitType> class PassManagerT;
struct AnalysisResolver;
// AnalysisID - Use the PassInfo to identify a pass...
typedef const PassInfo* AnalysisID;
-
//===----------------------------------------------------------------------===//
-// Pass interface - Implemented by all 'passes'. Subclass this if you are an
-// interprocedural optimization or you do not fit into any of the more
-// constrained passes described below.
-//
+/// Pass interface - Implemented by all 'passes'. Subclass this if you are an
+/// interprocedural optimization or you do not fit into any of the more
+/// constrained passes described below.
+///
class Pass {
friend class AnalysisResolver;
AnalysisResolver *Resolver; // AnalysisResolver this pass is owned by...
const PassInfo *PassInfoCache;
+
+ // AnalysisImpls - This keeps track of which passes implement the interfaces
+ // that are required by the current pass (to implement getAnalysis()).
+ //
+ std::vector<std::pair<const PassInfo*, Pass*> > AnalysisImpls;
+
void operator=(const Pass&); // DO NOT IMPLEMENT
Pass(const Pass &); // DO NOT IMPLEMENT
public:
Pass() : Resolver(0), PassInfoCache(0) {}
virtual ~Pass() {} // Destructor is virtual so we can be subclassed
- // getPassName - Return a nice clean name for a pass. This usually
- // implemented in terms of the name that is registered by one of the
- // Registration templates, but can be overloaded directly, and if nothing else
- // is available, C++ RTTI will be consulted to get a SOMEWHAT intelligable
- // name for the pass.
- //
+ /// getPassName - Return a nice clean name for a pass. This usually
+ /// implemented in terms of the name that is registered by one of the
+ /// Registration templates, but can be overloaded directly, and if nothing
+ /// else is available, C++ RTTI will be consulted to get a SOMEWHAT
+ /// intelligible name for the pass.
+ ///
virtual const char *getPassName() const;
- // getPassInfo - Return the PassInfo data structure that corresponds to this
- // pass... If the pass has not been registered, this will return null.
- //
+ /// getPassInfo - Return the PassInfo data structure that corresponds to this
+ /// pass... If the pass has not been registered, this will return null.
+ ///
const PassInfo *getPassInfo() const;
- // run - Run this pass, returning true if a modification was made to the
- // module argument. This should be implemented by all concrete subclasses.
- //
+ /// run - Run this pass, returning true if a modification was made to the
+ /// module argument. This should be implemented by all concrete subclasses.
+ ///
virtual bool run(Module &M) = 0;
- // print - Print out the internal state of the pass. This is called by
- // Analyze to print out the contents of an analysis. Otherwise it is not
- // neccesary to implement this method. Beware that the module pointer MAY be
- // null. This automatically forwards to a virtual function that does not
- // provide the Module* in case the analysis doesn't need it it can just be
- // ignored.
- //
+ /// print - Print out the internal state of the pass. This is called by
+ /// Analyze to print out the contents of an analysis. Otherwise it is not
+ /// necessary to implement this method. Beware that the module pointer MAY be
+ /// null. This automatically forwards to a virtual function that does not
+ /// provide the Module* in case the analysis doesn't need it it can just be
+ /// ignored.
+ ///
virtual void print(std::ostream &O, const Module *M) const { print(O); }
virtual void print(std::ostream &O) const;
void dump() const; // dump - call print(std::cerr, 0);
- // getAnalysisUsage - This function should be overriden by passes that need
- // analysis information to do their job. If a pass specifies that it uses a
- // particular analysis result to this function, it can then use the
- // getAnalysis<AnalysisType>() function, below.
- //
+ /// getAnalysisUsage - This function should be overriden by passes that need
+ /// analysis information to do their job. If a pass specifies that it uses a
+ /// particular analysis result to this function, it can then use the
+ /// getAnalysis<AnalysisType>() function, below.
+ ///
virtual void getAnalysisUsage(AnalysisUsage &Info) const {
// By default, no analysis results are used, all are invalidated.
}
- // releaseMemory() - This member can be implemented by a pass if it wants to
- // be able to release its memory when it is no longer needed. The default
- // behavior of passes is to hold onto memory for the entire duration of their
- // lifetime (which is the entire compile time). For pipelined passes, this
- // is not a big deal because that memory gets recycled every time the pass is
- // invoked on another program unit. For IP passes, it is more important to
- // free memory when it is unused.
- //
- // Optionally implement this function to release pass memory when it is no
- // longer used.
- //
+ /// releaseMemory() - This member can be implemented by a pass if it wants to
+ /// be able to release its memory when it is no longer needed. The default
+ /// behavior of passes is to hold onto memory for the entire duration of their
+ /// lifetime (which is the entire compile time). For pipelined passes, this
+ /// is not a big deal because that memory gets recycled every time the pass is
+ /// invoked on another program unit. For IP passes, it is more important to
+ /// free memory when it is unused.
+ ///
+ /// Optionally implement this function to release pass memory when it is no
+ /// longer used.
+ ///
virtual void releaseMemory() {}
// dumpPassStructure - Implement the -debug-passes=PassStructure option
virtual void dumpPassStructure(unsigned Offset = 0);
+
// getPassInfo - Static method to get the pass information from a class name.
template<typename AnalysisClass>
static const PassInfo *getClassPassInfo() {
return lookupPassInfo(typeid(AnalysisClass));
}
-protected:
// lookupPassInfo - Return the pass info object for the specified pass class,
// or null if it is not known.
static const PassInfo *lookupPassInfo(const std::type_info &TI);
- // getAnalysis<AnalysisType>() - This function is used by subclasses to get to
- // the analysis information that they claim to use by overriding the
- // getAnalysisUsage function.
- //
+ /// getAnalysisToUpdate<AnalysisType>() - This function is used by subclasses
+ /// to get to the analysis information that might be around that needs to be
+ /// updated. This is different than getAnalysis in that it can fail (ie the
+ /// analysis results haven't been computed), so should only be used if you
+ /// provide the capability to update an analysis that exists. This method is
+ /// often used by transformation APIs to update analysis results for a pass
+ /// automatically as the transform is performed.
+ ///
template<typename AnalysisType>
- AnalysisType &getAnalysis() {
+ AnalysisType *getAnalysisToUpdate() const; // Defined in PassAnalysisSupport.h
+
+ /// mustPreserveAnalysisID - This method serves the same function as
+ /// getAnalysisToUpdate, but works if you just have an AnalysisID. This
+ /// obviously cannot give you a properly typed instance of the class if you
+ /// don't have the class name available (use getAnalysisToUpdate if you do),
+ /// but it can tell you if you need to preserve the pass at least.
+ ///
+ bool mustPreserveAnalysisID(const PassInfo *AnalysisID) const;
+
+ /// getAnalysis<AnalysisType>() - This function is used by subclasses to get
+ /// to the analysis information that they claim to use by overriding the
+ /// getAnalysisUsage function.
+ ///
+ template<typename AnalysisType>
+ AnalysisType &getAnalysis() const {
assert(Resolver && "Pass has not been inserted into a PassManager object!");
const PassInfo *PI = getClassPassInfo<AnalysisType>();
- assert(PI && "getAnalysis for unregistered pass!");
- return *(AnalysisType*)Resolver->getAnalysis(PI);
+ return getAnalysisID<AnalysisType>(PI);
}
template<typename AnalysisType>
- AnalysisType &getAnalysisID(const PassInfo *PI) {
+ AnalysisType &getAnalysisID(const PassInfo *PI) const {
assert(Resolver && "Pass has not been inserted into a PassManager object!");
assert(PI && "getAnalysis for unregistered pass!");
- return *(AnalysisType*)Resolver->getAnalysis(PI);
- }
- // getAnalysisToUpdate<AnalysisType>() - This function is used by subclasses
- // to get to the analysis information that might be around that needs to be
- // updated. This is different than getAnalysis in that it can fail (ie the
- // analysis results haven't been computed), so should only be used if you
- // provide the capability to update an analysis that exists.
- //
- template<typename AnalysisType>
- AnalysisType *getAnalysisToUpdate() {
- assert(Resolver && "Pass not resident in a PassManager object!");
- const PassInfo *PI = getClassPassInfo<AnalysisType>();
- if (PI == 0) return 0;
- return (AnalysisType*)Resolver->getAnalysisToUpdate(PI);
+ // PI *must* appear in AnalysisImpls. Because the number of passes used
+ // should be a small number, we just do a linear search over a (dense)
+ // vector.
+ Pass *ResultPass = 0;
+ for (unsigned i = 0; ; ++i) {
+ assert(i != AnalysisImpls.size() &&
+ "getAnalysis*() called on an analysis that we not "
+ "'required' by pass!");
+ if (AnalysisImpls[i].first == PI) {
+ ResultPass = AnalysisImpls[i].second;
+ break;
+ }
+ }
+
+ // Because the AnalysisType may not be a subclass of pass (for
+ // AnalysisGroups), we must use dynamic_cast here to potentially adjust the
+ // return pointer (because the class may multiply inherit, once from pass,
+ // once from AnalysisType).
+ //
+ AnalysisType *Result = dynamic_cast<AnalysisType*>(ResultPass);
+ assert(Result && "Pass does not implement interface required!");
+ return *Result;
}
-
private:
friend class PassManagerT<Module>;
friend class PassManagerT<Function>;
P.print(OS, 0); return OS;
}
+
+
//===----------------------------------------------------------------------===//
-// FunctionPass class - This class is used to implement most global
-// optimizations. Optimizations should subclass this class if they meet the
-// following constraints:
-//
-// 1. Optimizations are organized globally, ie a function at a time
-// 2. Optimizing a function does not cause the addition or removal of any
-// functions in the module
-//
+/// ImmutablePass class - This class is used to provide information that does
+/// not need to be run. This is useful for things like target information and
+/// "basic" versions of AnalysisGroups.
+///
+struct ImmutablePass : public Pass {
+ /// initializePass - This method may be overriden by immutable passes to allow
+ /// them to perform various initialization actions they require. This is
+ /// primarily because an ImmutablePass can "require" another ImmutablePass,
+ /// and if it does, the overloaded version of initializePass may get access to
+ /// these passes with getAnalysis<>.
+ ///
+ virtual void initializePass() {}
+
+ /// ImmutablePasses are never run.
+ ///
+ virtual bool run(Module &M) { return false; }
+
+private:
+ friend class PassManagerT<Module>;
+ virtual void addToPassManager(PassManagerT<Module> *PM, AnalysisUsage &AU);
+};
+
+
+//===----------------------------------------------------------------------===//
+/// FunctionPass class - This class is used to implement most global
+/// optimizations. Optimizations should subclass this class if they meet the
+/// following constraints:
+///
+/// 1. Optimizations are organized globally, i.e., a function at a time
+/// 2. Optimizing a function does not cause the addition or removal of any
+/// functions in the module
+///
struct FunctionPass : public Pass {
- // doInitialization - Virtual method overridden by subclasses to do
- // any neccesary per-module initialization.
- //
+ /// doInitialization - Virtual method overridden by subclasses to do
+ /// any necessary per-module initialization.
+ ///
virtual bool doInitialization(Module &M) { return false; }
- // runOnFunction - Virtual method overriden by subclasses to do the
- // per-function processing of the pass.
- //
+ /// runOnFunction - Virtual method overriden by subclasses to do the
+ /// per-function processing of the pass.
+ ///
virtual bool runOnFunction(Function &F) = 0;
- // doFinalization - Virtual method overriden by subclasses to do any post
- // processing needed after all passes have run.
- //
+ /// doFinalization - Virtual method overriden by subclasses to do any post
+ /// processing needed after all passes have run.
+ ///
virtual bool doFinalization(Module &M) { return false; }
- // run - On a module, we run this pass by initializing, ronOnFunction'ing once
- // for every function in the module, then by finalizing.
- //
+ /// run - On a module, we run this pass by initializing, ronOnFunction'ing
+ /// once for every function in the module, then by finalizing.
+ ///
virtual bool run(Module &M);
- // run - On a function, we simply initialize, run the function, then finalize.
- //
+ /// run - On a function, we simply initialize, run the function, then
+ /// finalize.
+ ///
bool run(Function &F);
private:
//===----------------------------------------------------------------------===//
-// BasicBlockPass class - This class is used to implement most local
-// optimizations. Optimizations should subclass this class if they
-// meet the following constraints:
-// 1. Optimizations are local, operating on either a basic block or
-// instruction at a time.
-// 2. Optimizations do not modify the CFG of the contained function, or any
-// other basic block in the function.
-// 3. Optimizations conform to all of the contstraints of FunctionPass's.
-//
+/// BasicBlockPass class - This class is used to implement most local
+/// optimizations. Optimizations should subclass this class if they
+/// meet the following constraints:
+/// 1. Optimizations are local, operating on either a basic block or
+/// instruction at a time.
+/// 2. Optimizations do not modify the CFG of the contained function, or any
+/// other basic block in the function.
+/// 3. Optimizations conform to all of the constraints of FunctionPass's.
+///
struct BasicBlockPass : public FunctionPass {
- // runOnBasicBlock - Virtual method overriden by subclasses to do the
- // per-basicblock processing of the pass.
- //
+ /// doInitialization - Virtual method overridden by subclasses to do
+ /// any necessary per-module initialization.
+ ///
+ virtual bool doInitialization(Module &M) { return false; }
+
+ /// doInitialization - Virtual method overridden by BasicBlockPass subclasses
+ /// to do any necessary per-function initialization.
+ ///
+ virtual bool doInitialization(Function &F) { return false; }
+
+ /// runOnBasicBlock - Virtual method overriden by subclasses to do the
+ /// per-basicblock processing of the pass.
+ ///
virtual bool runOnBasicBlock(BasicBlock &BB) = 0;
+ /// doFinalization - Virtual method overriden by BasicBlockPass subclasses to
+ /// do any post processing needed after all passes have run.
+ ///
+ virtual bool doFinalization(Function &F) { return false; }
+
+ /// doFinalization - Virtual method overriden by subclasses to do any post
+ /// processing needed after all passes have run.
+ ///
+ virtual bool doFinalization(Module &M) { return false; }
+
+
// To run this pass on a function, we simply call runOnBasicBlock once for
// each function.
//
- virtual bool runOnFunction(Function &F);
+ bool runOnFunction(Function &F);
- // To run directly on the basic block, we initialize, runOnBasicBlock, then
- // finalize.
- //
+ /// To run directly on the basic block, we initialize, runOnBasicBlock, then
+ /// finalize.
+ ///
bool run(BasicBlock &BB);
private:
virtual void addToPassManager(PassManagerT<BasicBlock> *PM,AnalysisUsage &AU);
};
+} // End llvm namespace
+
// Include support files that contain important APIs commonly used by Passes,
-// but that we want to seperate out to make it easier to read the header files.
+// but that we want to separate out to make it easier to read the header files.
//
#include "llvm/PassSupport.h"
#include "llvm/PassAnalysisSupport.h"