1 //===-- Mangler.cpp - Self-contained c/asm llvm name mangler --------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // 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/STLExtras.h"
18 #include "llvm/ADT/StringExtras.h"
19 #include "llvm/ADT/StringMap.h"
22 static char HexDigit(int V) {
23 return V < 10 ? V+'0' : V+'A'-10;
26 static std::string MangleLetter(unsigned char C) {
27 char Result[] = { '_', HexDigit(C >> 4), HexDigit(C & 15), '_', 0 };
31 /// makeNameProper - We don't want identifier names non-C-identifier characters
32 /// in them, so mangle them as appropriate.
34 std::string Mangler::makeNameProper(const std::string &X, const char *Prefix) {
36 if (X.empty()) return X; // Empty names are uniqued by the caller.
38 // If PreserveAsmNames is set, names with asm identifiers are not modified.
39 if (PreserveAsmNames && X[0] == 1)
43 // If X does not start with (char)1, add the prefix.
44 std::string::const_iterator I = X.begin();
48 ++I; // Skip over the marker.
50 // Mangle the first letter specially, don't allow numbers.
51 if (*I >= '0' && *I <= '9')
52 Result += MangleLetter(*I++);
54 for (std::string::const_iterator E = X.end(); I != E; ++I) {
55 if (!isCharAcceptable(*I))
56 Result += MangleLetter(*I);
61 bool NeedsQuotes = false;
63 std::string::const_iterator I = X.begin();
65 ++I; // Skip over the marker.
67 // If the first character is a number, we need quotes.
68 if (*I >= '0' && *I <= '9')
71 // Do an initial scan of the string, checking to see if we need quotes or
72 // to escape a '"' or not.
74 for (std::string::const_iterator E = X.end(); I != E; ++I)
75 if (!isCharAcceptable(*I)) {
80 // In the common case, we don't need quotes. Handle this quickly.
88 // Otherwise, construct the string the expensive way.
91 // If X does not start with (char)1, add the prefix.
95 ++I; // Skip the marker if present.
97 for (std::string::const_iterator E = X.end(); I != E; ++I) {
105 Result = '"' + Result + '"';
110 /// getTypeID - Return a unique ID for the specified LLVM type.
112 unsigned Mangler::getTypeID(const Type *Ty) {
113 unsigned &E = TypeMap[Ty];
114 if (E == 0) E = ++TypeCounter;
118 std::string Mangler::getValueName(const Value *V) {
119 if (const GlobalValue *GV = dyn_cast<GlobalValue>(V))
120 return getValueName(GV);
122 std::string &Name = Memo[V];
124 return Name; // Return the already-computed name for V.
126 // Always mangle local names.
127 Name = "ltmp_" + utostr(Count++) + "_" + utostr(getTypeID(V->getType()));
132 std::string Mangler::getValueName(const GlobalValue *GV, const char * Suffix) {
133 // Check to see whether we've already named V.
134 std::string &Name = Memo[GV];
136 return Name; // Return the already-computed name for V.
138 // Name mangling occurs as follows:
139 // - If V is an intrinsic function, do not change name at all
140 // - Otherwise, mangling occurs if global collides with existing name.
141 if (isa<Function>(GV) && cast<Function>(GV)->isIntrinsic()) {
142 Name = GV->getNameStart(); // Is an intrinsic function
143 } else if (!GV->hasName()) {
144 // Must mangle the global into a unique ID.
145 unsigned TypeUniqueID = getTypeID(GV->getType());
146 static unsigned GlobalID = 0;
147 Name = "__unnamed_" + utostr(TypeUniqueID) + "_" + utostr(GlobalID++);
148 } else if (!MangledGlobals.count(GV)) {
149 Name = makeNameProper(GV->getName() + Suffix, Prefix);
151 unsigned TypeUniqueID = getTypeID(GV->getType());
152 Name = "l" + utostr(TypeUniqueID) + "_" + makeNameProper(GV->getName());
158 static void InsertName(GlobalValue *GV, StringMap<GlobalValue*> &Names,
159 SmallPtrSet<const GlobalValue*, 16> &MangledGlobals) {
160 if (!GV->hasName()) // We must mangle unnamed globals.
163 // Figure out if this is already used.
164 GlobalValue *&ExistingValue = Names[GV->getNameStart()];
165 if (!ExistingValue) {
170 // If GV is external but the existing one is static, mangle the existing one
171 if ((GV->hasExternalLinkage() || GV->hasDLLImportLinkage()) &&
172 !(ExistingValue->hasExternalLinkage()
173 || ExistingValue->hasDLLImportLinkage())) {
174 MangledGlobals.insert(ExistingValue);
176 } else if ((GV->hasExternalLinkage() ||
177 GV->hasDLLImportLinkage()) &&
178 (ExistingValue->hasExternalLinkage() ||
179 ExistingValue->hasDLLImportLinkage()) &&
180 GV->isDeclaration() &&
181 ExistingValue->isDeclaration()) {
182 // If the two globals both have external inkage, and are both external,
183 // don't mangle either of them, we just have some silly type mismatch.
185 // Otherwise, mangle GV
186 MangledGlobals.insert(GV);
191 Mangler::Mangler(Module &M, const char *prefix)
192 : Prefix(prefix), UseQuotes(false), PreserveAsmNames(false),
193 Count(0), TypeCounter(0) {
194 std::fill(AcceptableChars, array_endof(AcceptableChars), 0);
196 // Letters and numbers are acceptable.
197 for (unsigned char X = 'a'; X <= 'z'; ++X)
198 markCharAcceptable(X);
199 for (unsigned char X = 'A'; X <= 'Z'; ++X)
200 markCharAcceptable(X);
201 for (unsigned char X = '0'; X <= '9'; ++X)
202 markCharAcceptable(X);
204 // These chars are acceptable.
205 markCharAcceptable('_');
206 markCharAcceptable('$');
207 markCharAcceptable('.');
209 // Calculate which global values have names that will collide when we throw
210 // away type information.
211 StringMap<GlobalValue*> Names;
212 for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
213 InsertName(I, Names, MangledGlobals);
214 for (Module::global_iterator I = M.global_begin(), E = M.global_end();
216 InsertName(I, Names, MangledGlobals);