1 //===-- Mangler.cpp - Self-contained c/asm llvm name mangler --------------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // Unified name mangler for CWriter and assembly backends.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/Support/Mangler.h"
15 #include "llvm/DerivedTypes.h"
16 #include "llvm/Module.h"
17 #include "llvm/ADT/StringExtras.h"
20 static char HexDigit(int V) {
21 return V < 10 ? V+'0' : V+'A'-10;
24 static std::string MangleLetter(unsigned char C) {
25 return std::string("_")+HexDigit(C >> 4) + HexDigit(C & 15) + "_";
28 /// makeNameProper - We don't want identifier names non-C-identifier characters
29 /// in them, so mangle them as appropriate.
31 std::string Mangler::makeNameProper(const std::string &X, const char *Prefix) {
34 // If X does not start with (char)1, add the prefix.
35 std::string::const_iterator I = X.begin();
39 ++I; // Skip over the marker.
41 // Mangle the first letter specially, don't allow numbers...
42 if (*I >= '0' && *I <= '9')
43 Result += MangleLetter(*I++);
45 for (std::string::const_iterator E = X.end(); I != E; ++I)
46 if ((*I < 'a' || *I > 'z') && (*I < 'A' || *I > 'Z') &&
47 (*I < '0' || *I > '9') && *I != '_' && *I != '$')
48 Result += MangleLetter(*I);
54 /// getTypeID - Return a unique ID for the specified LLVM type.
56 unsigned Mangler::getTypeID(const Type *Ty) {
57 unsigned &E = TypeMap[Ty];
58 if (E == 0) E = ++TypeCounter;
62 std::string Mangler::getValueName(const Value *V) {
63 if (const GlobalValue *GV = dyn_cast<GlobalValue>(V))
64 return getValueName(GV);
66 std::string &Name = Memo[V];
68 return Name; // Return the already-computed name for V.
70 // Always mangle local names.
71 Name = "ltmp_" + utostr(Count++) + "_" + utostr(getTypeID(V->getType()));
76 std::string Mangler::getValueName(const GlobalValue *GV) {
77 // Check to see whether we've already named V.
78 std::string &Name = Memo[GV];
80 return Name; // Return the already-computed name for V.
82 // Name mangling occurs as follows:
83 // - If V is an intrinsic function, do not change name at all
84 // - Otherwise, mangling occurs if global collides with existing name.
85 if (isa<Function>(GV) && cast<Function>(GV)->getIntrinsicID()) {
86 Name = GV->getName(); // Is an intrinsic function
87 } else if (!MangledGlobals.count(GV)) {
88 Name = makeNameProper(GV->getName(), Prefix);
90 unsigned TypeUniqueID = getTypeID(GV->getType());
91 Name = "l" + utostr(TypeUniqueID) + "_" + makeNameProper(GV->getName());
97 void Mangler::InsertName(GlobalValue *GV,
98 std::map<std::string, GlobalValue*> &Names) {
99 if (!GV->hasName()) { // We must mangle unnamed globals.
100 MangledGlobals.insert(GV);
104 // Figure out if this is already used.
105 GlobalValue *&ExistingValue = Names[GV->getName()];
106 if (!ExistingValue) {
109 // If GV is external but the existing one is static, mangle the existing one
110 if (GV->hasExternalLinkage() && !ExistingValue->hasExternalLinkage()) {
111 MangledGlobals.insert(ExistingValue);
114 // Otherwise, mangle GV
115 MangledGlobals.insert(GV);
121 Mangler::Mangler(Module &m, const char *prefix)
122 : M(m), Prefix(prefix), TypeCounter(0), Count(0) {
123 // Calculate which global values have names that will collide when we throw
124 // away type information.
125 std::map<std::string, GlobalValue*> Names;
126 for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
127 InsertName(I, Names);
128 for (Module::global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I)
129 InsertName(I, Names);