1//===-------------------------- cxa_demangle.cpp --------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9// FIXME: (possibly) incomplete list of features that clang mangles that this
10// file does not yet support:
11// - C++ modules TS
12
13#include "demangle/ItaniumDemangle.h"
14#include "__cxxabi_config.h"
15#include <cassert>
16#include <cctype>
17#include <cstdio>
18#include <cstdlib>
19#include <cstring>
20#include <functional>
21#include <numeric>
22#include <utility>
23
24using namespace itanium_demangle;
25
26constexpr const char *itanium_demangle::FloatData<float>::spec;
27constexpr const char *itanium_demangle::FloatData<double>::spec;
28constexpr const char *itanium_demangle::FloatData<long double>::spec;
29
30// <discriminator> := _ <non-negative number> # when number < 10
31// := __ <non-negative number> _ # when number >= 10
32// extension := decimal-digit+ # at the end of string
33const char *itanium_demangle::parse_discriminator(const char *first,
34 const char *last) {
35 // parse but ignore discriminator
36 if (first != last) {
37 if (*first == '_') {
38 const char *t1 = first + 1;
39 if (t1 != last) {
40 if (std::isdigit(*t1))
41 first = t1 + 1;
42 else if (*t1 == '_') {
43 for (++t1; t1 != last && std::isdigit(*t1); ++t1)
44 ;
45 if (t1 != last && *t1 == '_')
46 first = t1 + 1;
47 }
48 }
49 } else if (std::isdigit(*first)) {
50 const char *t1 = first + 1;
51 for (; t1 != last && std::isdigit(*t1); ++t1)
52 ;
53 if (t1 == last)
54 first = last;
55 }
56 }
57 return first;
58}
59
60#ifndef NDEBUG
61namespace {
62struct DumpVisitor {
63 unsigned Depth = 0;
64 bool PendingNewline = false;
65
66 template<typename NodeT> static constexpr bool wantsNewline(const NodeT *) {
67 return true;
68 }
69 static bool wantsNewline(NodeArray A) { return !A.empty(); }
70 static constexpr bool wantsNewline(...) { return false; }
71
72 template<typename ...Ts> static bool anyWantNewline(Ts ...Vs) {
73 for (bool B : {wantsNewline(Vs)...})
74 if (B)
75 return true;
76 return false;
77 }
78
79 void printStr(const char *S) { fprintf(stderr, "%s", S); }
80 void print(StringView SV) {
81 fprintf(stderr, "\"%.*s\"", (int)SV.size(), SV.begin());
82 }
83 void print(const Node *N) {
84 if (N)
85 N->visit(std::ref(*this));
86 else
87 printStr("<null>");
88 }
89 void print(NodeArray A) {
90 ++Depth;
91 printStr("{");
92 bool First = true;
93 for (const Node *N : A) {
94 if (First)
95 print(N);
96 else
97 printWithComma(N);
98 First = false;
99 }
100 printStr("}");
101 --Depth;
102 }
103
104 // Overload used when T is exactly 'bool', not merely convertible to 'bool'.
105 void print(bool B) { printStr(B ? "true" : "false"); }
106
107 template <class T>
108 typename std::enable_if<std::is_unsigned<T>::value>::type print(T N) {
109 fprintf(stderr, "%llu", (unsigned long long)N);
110 }
111
112 template <class T>
113 typename std::enable_if<std::is_signed<T>::value>::type print(T N) {
114 fprintf(stderr, "%lld", (long long)N);
115 }
116
117 void print(ReferenceKind RK) {
118 switch (RK) {
119 case ReferenceKind::LValue:
120 return printStr("ReferenceKind::LValue");
121 case ReferenceKind::RValue:
122 return printStr("ReferenceKind::RValue");
123 }
124 }
125 void print(FunctionRefQual RQ) {
126 switch (RQ) {
127 case FunctionRefQual::FrefQualNone:
128 return printStr("FunctionRefQual::FrefQualNone");
129 case FunctionRefQual::FrefQualLValue:
130 return printStr("FunctionRefQual::FrefQualLValue");
131 case FunctionRefQual::FrefQualRValue:
132 return printStr("FunctionRefQual::FrefQualRValue");
133 }
134 }
135 void print(Qualifiers Qs) {
136 if (!Qs) return printStr("QualNone");
137 struct QualName { Qualifiers Q; const char *Name; } Names[] = {
138 {QualConst, "QualConst"},
139 {QualVolatile, "QualVolatile"},
140 {QualRestrict, "QualRestrict"},
141 };
142 for (QualName Name : Names) {
143 if (Qs & Name.Q) {
144 printStr(Name.Name);
145 Qs = Qualifiers(Qs & ~Name.Q);
146 if (Qs) printStr(" | ");
147 }
148 }
149 }
150 void print(SpecialSubKind SSK) {
151 switch (SSK) {
152 case SpecialSubKind::allocator:
153 return printStr("SpecialSubKind::allocator");
154 case SpecialSubKind::basic_string:
155 return printStr("SpecialSubKind::basic_string");
156 case SpecialSubKind::string:
157 return printStr("SpecialSubKind::string");
158 case SpecialSubKind::istream:
159 return printStr("SpecialSubKind::istream");
160 case SpecialSubKind::ostream:
161 return printStr("SpecialSubKind::ostream");
162 case SpecialSubKind::iostream:
163 return printStr("SpecialSubKind::iostream");
164 }
165 }
166 void print(TemplateParamKind TPK) {
167 switch (TPK) {
168 case TemplateParamKind::Type:
169 return printStr("TemplateParamKind::Type");
170 case TemplateParamKind::NonType:
171 return printStr("TemplateParamKind::NonType");
172 case TemplateParamKind::Template:
173 return printStr("TemplateParamKind::Template");
174 }
175 }
176
177 void newLine() {
178 printStr("\n");
179 for (unsigned I = 0; I != Depth; ++I)
180 printStr(" ");
181 PendingNewline = false;
182 }
183
184 template<typename T> void printWithPendingNewline(T V) {
185 print(V);
186 if (wantsNewline(V))
187 PendingNewline = true;
188 }
189
190 template<typename T> void printWithComma(T V) {
191 if (PendingNewline || wantsNewline(V)) {
192 printStr(",");
193 newLine();
194 } else {
195 printStr(", ");
196 }
197
198 printWithPendingNewline(V);
199 }
200
201 struct CtorArgPrinter {
202 DumpVisitor &Visitor;
203
204 template<typename T, typename ...Rest> void operator()(T V, Rest ...Vs) {
205 if (Visitor.anyWantNewline(V, Vs...))
206 Visitor.newLine();
207 Visitor.printWithPendingNewline(V);
208 int PrintInOrder[] = { (Visitor.printWithComma(Vs), 0)..., 0 };
209 (void)PrintInOrder;
210 }
211 };
212
213 template<typename NodeT> void operator()(const NodeT *Node) {
214 Depth += 2;
215 fprintf(stderr, "%s(", itanium_demangle::NodeKind<NodeT>::name());
216 Node->match(CtorArgPrinter{*this});
217 fprintf(stderr, ")");
218 Depth -= 2;
219 }
220
221 void operator()(const ForwardTemplateReference *Node) {
222 Depth += 2;
223 fprintf(stderr, "ForwardTemplateReference(");
224 if (Node->Ref && !Node->Printing) {
225 Node->Printing = true;
226 CtorArgPrinter{*this}(Node->Ref);
227 Node->Printing = false;
228 } else {
229 CtorArgPrinter{*this}(Node->Index);
230 }
231 fprintf(stderr, ")");
232 Depth -= 2;
233 }
234};
235}
236
237void itanium_demangle::Node::dump() const {
238 DumpVisitor V;
239 visit(std::ref(V));
240 V.newLine();
241}
242#endif
243
244namespace {
245class BumpPointerAllocator {
246 struct BlockMeta {
247 BlockMeta* Next;
248 size_t Current;
249 };
250
251 static constexpr size_t AllocSize = 4096;
252 static constexpr size_t UsableAllocSize = AllocSize - sizeof(BlockMeta);
253
254 alignas(long double) char InitialBuffer[AllocSize];
255 BlockMeta* BlockList = nullptr;
256
257 void grow() {
258 char* NewMeta = static_cast<char *>(std::malloc(AllocSize));
259 if (NewMeta == nullptr)
260 std::terminate();
261 BlockList = new (NewMeta) BlockMeta{BlockList, 0};
262 }
263
264 void* allocateMassive(size_t NBytes) {
265 NBytes += sizeof(BlockMeta);
266 BlockMeta* NewMeta = reinterpret_cast<BlockMeta*>(std::malloc(NBytes));
267 if (NewMeta == nullptr)
268 std::terminate();
269 BlockList->Next = new (NewMeta) BlockMeta{BlockList->Next, 0};
270 return static_cast<void*>(NewMeta + 1);
271 }
272
273public:
274 BumpPointerAllocator()
275 : BlockList(new (InitialBuffer) BlockMeta{nullptr, 0}) {}
276
277 void* allocate(size_t N) {
278 N = (N + 15u) & ~15u;
279 if (N + BlockList->Current >= UsableAllocSize) {
280 if (N > UsableAllocSize)
281 return allocateMassive(N);
282 grow();
283 }
284 BlockList->Current += N;
285 return static_cast<void*>(reinterpret_cast<char*>(BlockList + 1) +
286 BlockList->Current - N);
287 }
288
289 void reset() {
290 while (BlockList) {
291 BlockMeta* Tmp = BlockList;
292 BlockList = BlockList->Next;
293 if (reinterpret_cast<char*>(Tmp) != InitialBuffer)
294 std::free(Tmp);
295 }
296 BlockList = new (InitialBuffer) BlockMeta{nullptr, 0};
297 }
298
299 ~BumpPointerAllocator() { reset(); }
300};
301
302class DefaultAllocator {
303 BumpPointerAllocator Alloc;
304
305public:
306 void reset() { Alloc.reset(); }
307
308 template<typename T, typename ...Args> T *makeNode(Args &&...args) {
309 return new (Alloc.allocate(sizeof(T)))
310 T(std::forward<Args>(args)...);
311 }
312
313 void *allocateNodeArray(size_t sz) {
314 return Alloc.allocate(sizeof(Node *) * sz);
315 }
316};
317} // unnamed namespace
318
319//===----------------------------------------------------------------------===//
320// Code beyond this point should not be synchronized with LLVM.
321//===----------------------------------------------------------------------===//
322
323using Demangler = itanium_demangle::ManglingParser<DefaultAllocator>;
324
325namespace {
326enum : int {
327 demangle_invalid_args = -3,
328 demangle_invalid_mangled_name = -2,
329 demangle_memory_alloc_failure = -1,
330 demangle_success = 0,
331};
332}
333
334namespace __cxxabiv1 {
335extern "C" _LIBCXXABI_FUNC_VIS char *
336__cxa_demangle(const char *MangledName, char *Buf, size_t *N, int *Status) {
337 if (MangledName == nullptr || (Buf != nullptr && N == nullptr)) {
338 if (Status)
339 *Status = demangle_invalid_args;
340 return nullptr;
341 }
342
343 int InternalStatus = demangle_success;
344 Demangler Parser(MangledName, MangledName + std::strlen(MangledName));
345 OutputStream S;
346
347 Node *AST = Parser.parse();
348
349 if (AST == nullptr)
350 InternalStatus = demangle_invalid_mangled_name;
351 else if (!initializeOutputStream(Buf, N, S, 1024))
352 InternalStatus = demangle_memory_alloc_failure;
353 else {
354 assert(Parser.ForwardTemplateRefs.empty());
355 AST->print(S);
356 S += '\0';
357 if (N != nullptr)
358 *N = S.getCurrentPosition();
359 Buf = S.getBuffer();
360 }
361
362 if (Status)
363 *Status = InternalStatus;
364 return InternalStatus == demangle_success ? Buf : nullptr;
365}
366} // __cxxabiv1
367