1 //===- FindUsedTypes.cpp - Find all Types used by a module ----------------===//
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 pass is used to seek out all of the types in use by the program. Note
11 // that this analysis explicitly does not include types only used by the symbol
12 // table.
13 //
14 //===----------------------------------------------------------------------===//
15
16 #include "llvm/Analysis/FindUsedTypes.h"
17 #include "llvm/Constants.h"
18 #include "llvm/DerivedTypes.h"
19 #include "llvm/Module.h"
20 #include "llvm/Assembly/Writer.h"
21 #include "llvm/Support/InstIterator.h"
22 #include "llvm/Support/raw_ostream.h"
23 using namespace llvm;
24
25 char FindUsedTypes::ID = 0;
26 INITIALIZE_PASS(FindUsedTypes, "print-used-types",
27 "Find Used Types", false, true)
28
29 // IncorporateType - Incorporate one type and all of its subtypes into the
30 // collection of used types.
31 //
IncorporateType(Type * Ty)32 void FindUsedTypes::IncorporateType(Type *Ty) {
33 // If ty doesn't already exist in the used types map, add it now, otherwise
34 // return.
35 if (!UsedTypes.insert(Ty)) return; // Already contain Ty.
36
37 // Make sure to add any types this type references now.
38 //
39 for (Type::subtype_iterator I = Ty->subtype_begin(), E = Ty->subtype_end();
40 I != E; ++I)
41 IncorporateType(*I);
42 }
43
IncorporateValue(const Value * V)44 void FindUsedTypes::IncorporateValue(const Value *V) {
45 IncorporateType(V->getType());
46
47 // If this is a constant, it could be using other types...
48 if (const Constant *C = dyn_cast<Constant>(V)) {
49 if (!isa<GlobalValue>(C))
50 for (User::const_op_iterator OI = C->op_begin(), OE = C->op_end();
51 OI != OE; ++OI)
52 IncorporateValue(*OI);
53 }
54 }
55
56
57 // run - This incorporates all types used by the specified module
58 //
runOnModule(Module & m)59 bool FindUsedTypes::runOnModule(Module &m) {
60 UsedTypes.clear(); // reset if run multiple times...
61
62 // Loop over global variables, incorporating their types
63 for (Module::const_global_iterator I = m.global_begin(), E = m.global_end();
64 I != E; ++I) {
65 IncorporateType(I->getType());
66 if (I->hasInitializer())
67 IncorporateValue(I->getInitializer());
68 }
69
70 for (Module::iterator MI = m.begin(), ME = m.end(); MI != ME; ++MI) {
71 IncorporateType(MI->getType());
72 const Function &F = *MI;
73
74 // Loop over all of the instructions in the function, adding their return
75 // type as well as the types of their operands.
76 //
77 for (const_inst_iterator II = inst_begin(F), IE = inst_end(F);
78 II != IE; ++II) {
79 const Instruction &I = *II;
80
81 IncorporateType(I.getType()); // Incorporate the type of the instruction
82 for (User::const_op_iterator OI = I.op_begin(), OE = I.op_end();
83 OI != OE; ++OI)
84 IncorporateValue(*OI); // Insert inst operand types as well
85 }
86 }
87
88 return false;
89 }
90
91 // Print the types found in the module. If the optional Module parameter is
92 // passed in, then the types are printed symbolically if possible, using the
93 // symbol table from the module.
94 //
print(raw_ostream & OS,const Module * M) const95 void FindUsedTypes::print(raw_ostream &OS, const Module *M) const {
96 OS << "Types in use by this module:\n";
97 for (SetVector<Type *>::const_iterator I = UsedTypes.begin(),
98 E = UsedTypes.end(); I != E; ++I) {
99 OS << " " << **I << '\n';
100 }
101 }
102