PseudoSourceValue.cpp revision 6553155172a2e74feff1253837daa608123de54a 
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>
22using namespace llvm;
23
24static ManagedStatic<PseudoSourceValue[4]> PSVs;
25
26const PseudoSourceValue *PseudoSourceValue::getStack()
27{ return &(*PSVs)[0]; }
28const PseudoSourceValue *PseudoSourceValue::getGOT()
29{ return &(*PSVs)[1]; }
30const PseudoSourceValue *PseudoSourceValue::getJumpTable()
31{ return &(*PSVs)[2]; }
32const PseudoSourceValue *PseudoSourceValue::getConstantPool()
33{ return &(*PSVs)[3]; }
34
35static const char *const PSVNames[] = {
36  "Stack",
37  "GOT",
38  "JumpTable",
39  "ConstantPool"
40};
41
42// FIXME: THIS IS A HACK!!!!
43// Eventually these should be uniqued on LLVMContext rather than in a managed
44// static.  For now, we can safely use the global context for the time being to
45// squeak by.
46PseudoSourceValue::PseudoSourceValue() :
47  Value(Type::getInt8PtrTy(getGlobalContext()),
48        PseudoSourceValueVal) {}
49
50void PseudoSourceValue::printCustom(raw_ostream &O) const {
51  O << PSVNames[this - *PSVs];
52}
53
54namespace {
55  /// FixedStackPseudoSourceValue - A specialized PseudoSourceValue
56  /// for holding FixedStack values, which must include a frame
57  /// index.
58  class VISIBILITY_HIDDEN FixedStackPseudoSourceValue
59    : public PseudoSourceValue {
60    const int FI;
61  public:
62    explicit FixedStackPseudoSourceValue(int fi) : FI(fi) {}
63
64    virtual bool isConstant(const MachineFrameInfo *MFI) const;
65
66    virtual void printCustom(raw_ostream &OS) const {
67      OS << "FixedStack" << FI;
68    }
69  };
70}
71
72static ManagedStatic<std::map<int, const PseudoSourceValue *> > FSValues;
73
74const PseudoSourceValue *PseudoSourceValue::getFixedStack(int FI) {
75  const PseudoSourceValue *&V = (*FSValues)[FI];
76  if (!V)
77    V = new FixedStackPseudoSourceValue(FI);
78  return V;
79}
80
81bool PseudoSourceValue::isConstant(const MachineFrameInfo *) const {
82  if (this == getStack())
83    return false;
84  if (this == getGOT() ||
85      this == getConstantPool() ||
86      this == getJumpTable())
87    return true;
88  llvm_unreachable("Unknown PseudoSourceValue!");
89  return false;
90}
91
92bool FixedStackPseudoSourceValue::isConstant(const MachineFrameInfo *MFI) const{
93  return MFI && MFI->isImmutableObjectIndex(FI);
94}
95