FindUsedTypes.cpp revision f4de63f65fa995e68e3cd268117ab065068be413 
1//===- FindUsedTypes.h - Find all Types used by a module --------------------=//
2//
3// This pass is used to seek out all of the types in use by the program.
4//
5//===----------------------------------------------------------------------===//
6
7#include "llvm/Analysis/FindUsedTypes.h"
8#include "llvm/Assembly/CachedWriter.h"
9#include "llvm/SymbolTable.h"
10#include "llvm/GlobalVariable.h"
11#include "llvm/DerivedTypes.h"
12
13// IncorporateType - Incorporate one type and all of its subtypes into the
14// collection of used types.
15//
16void FindUsedTypes::IncorporateType(const Type *Ty) {
17  if (UsedTypes.count(Ty)) return;  // Already contain Ty.
18
19  // If ty doesn't already exist in the used types map, add it now.
20  //
21  UsedTypes.insert(Ty);
22
23  // Make sure to add any types this type references now.
24  //
25  for (Type::subtype_iterator I = Ty->subtype_begin(), E = Ty->subtype_end();
26       I != E; ++I)
27    IncorporateType(*I);
28}
29
30// IncorporateSymbolTable - Add all types referenced by the specified symtab
31// into the collection of used types.
32//
33void FindUsedTypes::IncorporateSymbolTable(const SymbolTable *ST) {
34  assert(0 && "Unimp");
35}
36
37
38// doInitialization - This loops over global constants defined in the
39// module, converting them to their new type.
40//
41bool FindUsedTypes::doInitialization(Module *m) {
42  const Module *M = m;
43  if (IncludeSymbolTables && M->hasSymbolTable())
44    IncorporateSymbolTable(M->getSymbolTable()); // Add symtab first...
45
46  // Loop over global variables, incorporating their types
47  for (Module::const_giterator I = M->gbegin(), E = M->gend(); I != E; ++I)
48    IncorporateType((*I)->getType());
49  return false;
50}
51
52// doPerMethodWork - This incorporates all types used by the specified method
53//
54bool FindUsedTypes::runOnMethod(Method *m) {
55  const Method *M = m;
56  if (IncludeSymbolTables && M->hasSymbolTable())
57  IncorporateSymbolTable(M->getSymbolTable()); // Add symtab first...
58
59  // Loop over all of the instructions in the method, adding their return type
60  // as well as the types of their operands.
61  //
62  for (Method::const_inst_iterator II = M->inst_begin(), IE = M->inst_end();
63       II != IE; ++II) {
64    const Instruction *I = *II;
65    const Type *Ty = I->getType();
66
67    IncorporateType(Ty);  // Incorporate the type of the instruction
68    for (User::const_op_iterator OI = I->op_begin(), OE = I->op_end();
69         OI != OE; ++OI)
70      if ((*OI)->getType() != Ty)          // Avoid set lookup in common case
71        IncorporateType((*OI)->getType()); // Insert inst operand types as well
72  }
73
74  return false;
75}
76
77// Print the types found in the module.  If the optional Module parameter is
78// passed in, then the types are printed symbolically if possible, using the
79// symbol table from the module.
80//
81void FindUsedTypes::printTypes(std::ostream &o, const Module *M = 0) const {
82  o << "Types in use by this module:\n";
83  if (M) {
84    CachedWriter CW(M, o);
85    for (std::set<const Type *>::const_iterator I = UsedTypes.begin(),
86           E = UsedTypes.end(); I != E; ++I)
87      CW << "  " << *I << "\n";
88  } else
89    for (std::set<const Type *>::const_iterator I = UsedTypes.begin(),
90           E = UsedTypes.end(); I != E; ++I)
91      o << "  " << *I << "\n";
92}
93