llvm-6502/include/llvm/Transforms/Utils/SSI.h
Nick Lewycky 715029478c Add Static Single Information construction pass written by André Tavares!
Use it by requiring it through the pass manager, then calling its createSSI
method on the variables that you want in SSI form.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74780 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-03 19:28:36 +00:00

103 lines
3.3 KiB
C++

//===------------------- SSI.h - Creates SSI Representation -----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This pass converts a list of variables to the Static Single Information
// form. This is a program representation described by Scott Ananian in his
// Master Thesis: "The Static Single Information Form (1999)".
// We are building an on-demand representation, that is, we do not convert
// every single variable in the target function to SSI form. Rather, we receive
// a list of target variables that must be converted. We also do not
// completely convert a target variable to the SSI format. Instead, we only
// change the variable in the points where new information can be attached
// to its live range, that is, at branch points.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_TRANSFORMS_UTILS_SSI_H
#define LLVM_TRANSFORMS_UTILS_SSI_H
#include "llvm/Pass.h"
#include "llvm/ADT/BitVector.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallVector.h"
namespace llvm {
class DominatorTree;
class PHINode;
class Instruction;
class CmpInst;
class SSI : public FunctionPass {
public:
static char ID; // Pass identification, replacement for typeid.
SSI() :
FunctionPass(&ID) {
}
void getAnalysisUsage(AnalysisUsage &AU) const;
/// runOnMachineFunction - pass entry point
bool runOnFunction(Function&);
void createSSI(SmallVectorImpl<Instruction *> &value);
private:
// Variables always live
DominatorTree *DT_;
// Stores variables created by SSI
SmallPtrSet<Instruction *, 16> created;
// These variables are only live for each creation
unsigned num_values;
// Has a bit for each variable, true if it needs to be created
// and false otherwise
BitVector needConstruction;
// Phis created by SSI
DenseMap<PHINode *, unsigned> phis;
// Sigmas created by SSI
DenseMap<PHINode *, unsigned> sigmas;
// Phi nodes that have a phi as operand and has to be fixed
SmallPtrSet<PHINode *, 1> phisToFix;
// List of definition points for every variable
SmallVector<SmallVector<BasicBlock *, 1>, 0> defsites;
// Basic Block of the original definition of each variable
SmallVector<BasicBlock *, 0> value_original;
// Stack of last seen definition of a variable
SmallVector<SmallVector<Instruction *, 1>, 0> value_stack;
void insertSigmaFunctions(SmallVectorImpl<Instruction *> &value);
void insertPhiFunctions(SmallVectorImpl<Instruction *> &value);
void renameInit(SmallVectorImpl<Instruction *> &value);
void rename(BasicBlock *BB);
void substituteUse(Instruction *I);
bool dominateAny(BasicBlock *BB, Instruction *value);
void fixPhis();
unsigned getPositionPhi(PHINode *PN);
unsigned getPositionSigma(PHINode *PN);
unsigned isUsedInTerminator(CmpInst *CI);
void init(SmallVectorImpl<Instruction *> &value);
void clean();
};
} // end namespace
#endif