lib/CodeGen/PseudoSourceValue.cpp

   1 //===-- llvm/CodeGen/PseudoSourceValue.cpp ----------------------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file implements the PseudoSourceValue class.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/CodeGen/MachineFrameInfo.h"
  15 #include "llvm/CodeGen/PseudoSourceValue.h"
  16 #include "llvm/DerivedTypes.h"
  17 #include "llvm/Support/Compiler.h"
  18 #include "llvm/Support/ErrorHandling.h"
  19 #include "llvm/Support/ManagedStatic.h"
  20 #include "llvm/Support/raw_ostream.h"
  21 #include <map>
  22 using namespace llvm;
  23
  24 static ManagedStatic<PseudoSourceValue[4]> PSVs;
  25
  26 const PseudoSourceValue *PseudoSourceValue::getStack()
  27 { return &(*PSVs)[0]; }
  28 const PseudoSourceValue *PseudoSourceValue::getGOT()
  29 { return &(*PSVs)[1]; }
  30 const PseudoSourceValue *PseudoSourceValue::getJumpTable()
  31 { return &(*PSVs)[2]; }
  32 const PseudoSourceValue *PseudoSourceValue::getConstantPool()
  33 { return &(*PSVs)[3]; }
  34
  35 static const char *const PSVNames[] = {
  36   "Stack",
  37   "GOT",
  38   "JumpTable",
  39   "ConstantPool"
  40 };
  41
  42 PseudoSourceValue::PseudoSourceValue() :
  43   Value(PointerType::getUnqual(Type::Int8Ty), PseudoSourceValueVal) {}
  44
  45 void PseudoSourceValue::dump() const {
  46   print(errs()); errs() << '\n';
  47 }
  48
  49 void PseudoSourceValue::print(raw_ostream &OS) const {
  50   OS << PSVNames[this - *PSVs];
  51 }
  52
  53 namespace {
  54   /// FixedStackPseudoSourceValue - A specialized PseudoSourceValue
  55   /// for holding FixedStack values, which must include a frame
  56   /// index.
  57   class VISIBILITY_HIDDEN FixedStackPseudoSourceValue
  58     : public PseudoSourceValue {
  59     const int FI;
  60   public:
  61     explicit FixedStackPseudoSourceValue(int fi) : FI(fi) {}
  62
  63     virtual bool isConstant(const MachineFrameInfo *MFI) const;
  64
  65     virtual void print(raw_ostream &OS) const {
  66       OS << "FixedStack" << FI;
  67     }
  68   };
  69 }
  70
  71 static ManagedStatic<std::map<int, const PseudoSourceValue *> > FSValues;
  72
  73 const PseudoSourceValue *PseudoSourceValue::getFixedStack(int FI) {
  74   const PseudoSourceValue *&V = (*FSValues)[FI];
  75   if (!V)
  76     V = new FixedStackPseudoSourceValue(FI);
  77   return V;
  78 }
  79
  80 bool PseudoSourceValue::isConstant(const MachineFrameInfo *) const {
  81   if (this == getStack())
  82     return false;
  83   if (this == getGOT() ||
  84       this == getConstantPool() ||
  85       this == getJumpTable())
  86     return true;
  87   llvm_unreachable("Unknown PseudoSourceValue!");
  88   return false;
  89 }
  90
  91 bool FixedStackPseudoSourceValue::isConstant(const MachineFrameInfo *MFI) const{
  92   return MFI && MFI->isImmutableObjectIndex(FI);
  93 }