1 //===--- Mangle.cpp - Mangle C++ Names --------------------------*- C++ -*-===//
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 // Implements generic name mangling support for blocks and Objective-C.
12 //===----------------------------------------------------------------------===//
13 #include "clang/AST/Attr.h"
14 #include "clang/AST/ASTContext.h"
15 #include "clang/AST/Decl.h"
16 #include "clang/AST/DeclCXX.h"
17 #include "clang/AST/DeclObjC.h"
18 #include "clang/AST/DeclTemplate.h"
19 #include "clang/AST/ExprCXX.h"
20 #include "clang/AST/Mangle.h"
21 #include "clang/Basic/ABI.h"
22 #include "clang/Basic/SourceManager.h"
23 #include "clang/Basic/TargetInfo.h"
24 #include "llvm/ADT/StringExtras.h"
25 #include "llvm/Support/ErrorHandling.h"
26 #include "llvm/Support/raw_ostream.h"
28 #define MANGLE_CHECKER 0
34 using namespace clang;
36 // FIXME: For blocks we currently mimic GCC's mangling scheme, which leaves
37 // much to be desired. Come up with a better mangling scheme.
39 static void mangleFunctionBlock(MangleContext &Context,
43 unsigned discriminator = Context.getBlockId(BD, true);
44 if (discriminator == 0)
45 Out << "__" << Outer << "_block_invoke";
47 Out << "__" << Outer << "_block_invoke_" << discriminator+1;
50 void MangleContext::anchor() { }
59 static bool isExternC(const NamedDecl *ND) {
60 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND))
61 return FD->isExternC();
62 return cast<VarDecl>(ND)->isExternC();
65 static CCMangling getCallingConvMangling(const ASTContext &Context,
66 const NamedDecl *ND) {
67 const TargetInfo &TI = Context.getTargetInfo();
68 const llvm::Triple &Triple = TI.getTriple();
69 if (!Triple.isOSWindows() ||
70 !(Triple.getArch() == llvm::Triple::x86 ||
71 Triple.getArch() == llvm::Triple::x86_64))
74 if (Context.getLangOpts().CPlusPlus && !isExternC(ND) &&
75 TI.getCXXABI() == TargetCXXABI::Microsoft)
78 const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND);
81 QualType T = FD->getType();
83 const FunctionType *FT = T->castAs<FunctionType>();
85 CallingConv CC = FT->getCallConv();
93 case CC_X86VectorCall:
98 bool MangleContext::shouldMangleDeclName(const NamedDecl *D) {
99 const ASTContext &ASTContext = getASTContext();
101 CCMangling CC = getCallingConvMangling(ASTContext, D);
105 // In C, functions with no attributes never need to be mangled. Fastpath them.
106 if (!getASTContext().getLangOpts().CPlusPlus && !D->hasAttrs())
109 // Any decl can be declared with __asm("foo") on it, and this takes precedence
110 // over all other naming in the .o file.
111 if (D->hasAttr<AsmLabelAttr>())
114 return shouldMangleCXXName(D);
117 void MangleContext::mangleName(const NamedDecl *D, raw_ostream &Out) {
118 // Any decl can be declared with __asm("foo") on it, and this takes precedence
119 // over all other naming in the .o file.
120 if (const AsmLabelAttr *ALA = D->getAttr<AsmLabelAttr>()) {
121 // If we have an asm name, then we use it as the mangling.
123 // Adding the prefix can cause problems when one file has a "foo" and
124 // another has a "\01foo". That is known to happen on ELF with the
125 // tricks normally used for producing aliases (PR9177). Fortunately the
126 // llvm mangler on ELF is a nop, so we can just avoid adding the \01
127 // marker. We also avoid adding the marker if this is an alias for an
129 StringRef UserLabelPrefix =
130 getASTContext().getTargetInfo().getUserLabelPrefix();
131 if (!UserLabelPrefix.empty() && !ALA->getLabel().startswith("llvm."))
132 Out << '\01'; // LLVM IR Marker for __asm("foo")
134 Out << ALA->getLabel();
138 const ASTContext &ASTContext = getASTContext();
139 CCMangling CC = getCallingConvMangling(ASTContext, D);
140 bool MCXX = shouldMangleCXXName(D);
141 const TargetInfo &TI = Context.getTargetInfo();
142 if (CC == CCM_Other || (MCXX && TI.getCXXABI() == TargetCXXABI::Microsoft)) {
143 if (const ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D))
144 mangleObjCMethodName(OMD, Out);
146 mangleCXXName(D, Out);
153 else if (CC == CCM_Fast)
157 Out << D->getIdentifier()->getName();
158 else if (const ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D))
159 mangleObjCMethodName(OMD, Out);
161 mangleCXXName(D, Out);
163 const FunctionDecl *FD = cast<FunctionDecl>(D);
164 const FunctionType *FT = FD->getType()->castAs<FunctionType>();
165 const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FT);
166 if (CC == CCM_Vector)
173 assert(!Proto->isVariadic());
174 unsigned ArgWords = 0;
175 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD))
178 for (const auto &AT : Proto->param_types())
179 // Size should be aligned to pointer size.
180 ArgWords += llvm::RoundUpToAlignment(ASTContext.getTypeSize(AT),
181 TI.getPointerWidth(0)) /
182 TI.getPointerWidth(0);
183 Out << ((TI.getPointerWidth(0) / 8) * ArgWords);
186 void MangleContext::mangleGlobalBlock(const BlockDecl *BD,
189 unsigned discriminator = getBlockId(BD, false);
191 if (shouldMangleDeclName(ID))
194 Out << ID->getIdentifier()->getName();
197 if (discriminator == 0)
198 Out << "_block_invoke";
200 Out << "_block_invoke_" << discriminator+1;
203 void MangleContext::mangleCtorBlock(const CXXConstructorDecl *CD,
204 CXXCtorType CT, const BlockDecl *BD,
205 raw_ostream &ResStream) {
206 SmallString<64> Buffer;
207 llvm::raw_svector_ostream Out(Buffer);
208 mangleCXXCtor(CD, CT, Out);
209 mangleFunctionBlock(*this, Buffer, BD, ResStream);
212 void MangleContext::mangleDtorBlock(const CXXDestructorDecl *DD,
213 CXXDtorType DT, const BlockDecl *BD,
214 raw_ostream &ResStream) {
215 SmallString<64> Buffer;
216 llvm::raw_svector_ostream Out(Buffer);
217 mangleCXXDtor(DD, DT, Out);
218 mangleFunctionBlock(*this, Buffer, BD, ResStream);
221 void MangleContext::mangleBlock(const DeclContext *DC, const BlockDecl *BD,
223 assert(!isa<CXXConstructorDecl>(DC) && !isa<CXXDestructorDecl>(DC));
225 SmallString<64> Buffer;
226 llvm::raw_svector_ostream Stream(Buffer);
227 if (const ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(DC)) {
228 mangleObjCMethodName(Method, Stream);
230 assert((isa<NamedDecl>(DC) || isa<BlockDecl>(DC)) &&
231 "expected a NamedDecl or BlockDecl");
232 if (isa<BlockDecl>(DC))
233 for (; DC && isa<BlockDecl>(DC); DC = DC->getParent())
234 (void) getBlockId(cast<BlockDecl>(DC), true);
235 assert((isa<TranslationUnitDecl>(DC) || isa<NamedDecl>(DC)) &&
236 "expected a TranslationUnitDecl or a NamedDecl");
237 if (const auto *CD = dyn_cast<CXXConstructorDecl>(DC))
238 mangleCtorBlock(CD, /*CT*/ Ctor_Complete, BD, Out);
239 else if (const auto *DD = dyn_cast<CXXDestructorDecl>(DC))
240 mangleDtorBlock(DD, /*DT*/ Dtor_Complete, BD, Out);
241 else if (auto ND = dyn_cast<NamedDecl>(DC)) {
242 if (!shouldMangleDeclName(ND) && ND->getIdentifier())
243 Stream << ND->getIdentifier()->getName();
245 // FIXME: We were doing a mangleUnqualifiedName() before, but that's
246 // a private member of a class that will soon itself be private to the
247 // Itanium C++ ABI object. What should we do now? Right now, I'm just
248 // calling the mangleName() method on the MangleContext; is there a
250 mangleName(ND, Stream);
254 mangleFunctionBlock(*this, Buffer, BD, Out);
257 void MangleContext::mangleObjCMethodName(const ObjCMethodDecl *MD,
259 SmallString<64> Name;
260 llvm::raw_svector_ostream OS(Name);
262 const ObjCContainerDecl *CD =
263 dyn_cast<ObjCContainerDecl>(MD->getDeclContext());
264 assert (CD && "Missing container decl in GetNameForMethod");
265 OS << (MD->isInstanceMethod() ? '-' : '+') << '[' << CD->getName();
266 if (const ObjCCategoryImplDecl *CID = dyn_cast<ObjCCategoryImplDecl>(CD))
267 OS << '(' << *CID << ')';
269 MD->getSelector().print(OS);
272 Out << OS.str().size() << OS.str();