llvm-6502/include/llvm/CodeGen/MachineLoopInfo.h
Owen Anderson 081c34b725 Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which
must be called in the pass's constructor.  This function uses static dependency declarations to recursively initialize
the pass's dependencies.

Clients that only create passes through the createFooPass() APIs will require no changes.  Clients that want to use the
CommandLine options for passes will need to manually call the appropriate initialization functions in PassInitialization.h
before parsing commandline arguments.

I have tested this with all standard configurations of clang and llvm-gcc on Darwin.  It is possible that there are problems
with the static dependencies that will only be visible with non-standard options.  If you encounter any crash in pass
registration/creation, please send the testcase to me directly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116820 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-19 17:21:58 +00:00

179 lines
6.0 KiB
C++

//===- llvm/CodeGen/MachineLoopInfo.h - Natural Loop Calculator -*- 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 the MachineLoopInfo class that is used to identify natural
// loops and determine the loop depth of various nodes of the CFG. Note that
// natural loops may actually be several loops that share the same header node.
//
// This analysis calculates the nesting structure of loops in a function. For
// each natural loop identified, this analysis identifies natural loops
// contained entirely within the loop and the basic blocks the make up the loop.
//
// It can calculate on the fly various bits of information, for example:
//
// * whether there is a preheader for the loop
// * the number of back edges to the header
// * whether or not a particular block branches out of the loop
// * the successor blocks of the loop
// * the loop depth
// * the trip count
// * etc...
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CODEGEN_MACHINE_LOOP_INFO_H
#define LLVM_CODEGEN_MACHINE_LOOP_INFO_H
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/Analysis/LoopInfo.h"
namespace llvm {
class MachineLoop : public LoopBase<MachineBasicBlock, MachineLoop> {
public:
MachineLoop();
/// getTopBlock - Return the "top" block in the loop, which is the first
/// block in the linear layout, ignoring any parts of the loop not
/// contiguous with the part the contains the header.
MachineBasicBlock *getTopBlock();
/// getBottomBlock - Return the "bottom" block in the loop, which is the last
/// block in the linear layout, ignoring any parts of the loop not
/// contiguous with the part the contains the header.
MachineBasicBlock *getBottomBlock();
void dump() const;
private:
friend class LoopInfoBase<MachineBasicBlock, MachineLoop>;
explicit MachineLoop(MachineBasicBlock *MBB)
: LoopBase<MachineBasicBlock, MachineLoop>(MBB) {}
};
class MachineLoopInfo : public MachineFunctionPass {
LoopInfoBase<MachineBasicBlock, MachineLoop> LI;
friend class LoopBase<MachineBasicBlock, MachineLoop>;
void operator=(const MachineLoopInfo &); // do not implement
MachineLoopInfo(const MachineLoopInfo &); // do not implement
public:
static char ID; // Pass identification, replacement for typeid
MachineLoopInfo() : MachineFunctionPass(ID) {
initializeMachineLoopInfoPass(*PassRegistry::getPassRegistry());
}
LoopInfoBase<MachineBasicBlock, MachineLoop>& getBase() { return LI; }
/// iterator/begin/end - The interface to the top-level loops in the current
/// function.
///
typedef LoopInfoBase<MachineBasicBlock, MachineLoop>::iterator iterator;
inline iterator begin() const { return LI.begin(); }
inline iterator end() const { return LI.end(); }
bool empty() const { return LI.empty(); }
/// getLoopFor - Return the inner most loop that BB lives in. If a basic
/// block is in no loop (for example the entry node), null is returned.
///
inline MachineLoop *getLoopFor(const MachineBasicBlock *BB) const {
return LI.getLoopFor(BB);
}
/// operator[] - same as getLoopFor...
///
inline const MachineLoop *operator[](const MachineBasicBlock *BB) const {
return LI.getLoopFor(BB);
}
/// getLoopDepth - Return the loop nesting level of the specified block...
///
inline unsigned getLoopDepth(const MachineBasicBlock *BB) const {
return LI.getLoopDepth(BB);
}
// isLoopHeader - True if the block is a loop header node
inline bool isLoopHeader(MachineBasicBlock *BB) const {
return LI.isLoopHeader(BB);
}
/// runOnFunction - Calculate the natural loop information.
///
virtual bool runOnMachineFunction(MachineFunction &F);
virtual void releaseMemory() { LI.releaseMemory(); }
virtual void getAnalysisUsage(AnalysisUsage &AU) const;
/// removeLoop - This removes the specified top-level loop from this loop info
/// object. The loop is not deleted, as it will presumably be inserted into
/// another loop.
inline MachineLoop *removeLoop(iterator I) { return LI.removeLoop(I); }
/// changeLoopFor - Change the top-level loop that contains BB to the
/// specified loop. This should be used by transformations that restructure
/// the loop hierarchy tree.
inline void changeLoopFor(MachineBasicBlock *BB, MachineLoop *L) {
LI.changeLoopFor(BB, L);
}
/// changeTopLevelLoop - Replace the specified loop in the top-level loops
/// list with the indicated loop.
inline void changeTopLevelLoop(MachineLoop *OldLoop, MachineLoop *NewLoop) {
LI.changeTopLevelLoop(OldLoop, NewLoop);
}
/// addTopLevelLoop - This adds the specified loop to the collection of
/// top-level loops.
inline void addTopLevelLoop(MachineLoop *New) {
LI.addTopLevelLoop(New);
}
/// removeBlock - This method completely removes BB from all data structures,
/// including all of the Loop objects it is nested in and our mapping from
/// MachineBasicBlocks to loops.
void removeBlock(MachineBasicBlock *BB) {
LI.removeBlock(BB);
}
};
// Allow clients to walk the list of nested loops...
template <> struct GraphTraits<const MachineLoop*> {
typedef const MachineLoop NodeType;
typedef MachineLoopInfo::iterator ChildIteratorType;
static NodeType *getEntryNode(const MachineLoop *L) { return L; }
static inline ChildIteratorType child_begin(NodeType *N) {
return N->begin();
}
static inline ChildIteratorType child_end(NodeType *N) {
return N->end();
}
};
template <> struct GraphTraits<MachineLoop*> {
typedef MachineLoop NodeType;
typedef MachineLoopInfo::iterator ChildIteratorType;
static NodeType *getEntryNode(MachineLoop *L) { return L; }
static inline ChildIteratorType child_begin(NodeType *N) {
return N->begin();
}
static inline ChildIteratorType child_end(NodeType *N) {
return N->end();
}
};
} // End llvm namespace
#endif