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