Merge demangler changes over to libcxxabi

[zturner]

Summary

I actually tried to compile this on Windows, but was unsuccessful. I guess the only way to test it would be with a linux environment. Sorry for the trouble, but hopefully this at least saves you some of the gruntwork.

[erik.pilkington]

$ diff llvm-project/libcxxabi/src/demangle/StringView.h llvm-project/llvm/lib/Demangle/StringView.h gives a bunch of junk, I used to be able to just use a script that basically called patch to copy the bulk of the changes over. Did you call clang-format or something?

I think this is fine though, so after deformatting and adding that include feel free to commit!

libcxxabi/src/demangle/Compiler.h

23 ↗

(On Diff #156384)

This depends on __cxxabi_config.h to make sure that __has_attribute is defined on compilers that don't support it. Please add the include.

[thakis]

libcxxabi/src/demangle/Compiler.h

23 ↗

(On Diff #156384)

Is there any harm to just #ifndef #def here instead of pulling in that whole header?

[llvm-commits]

Or just doing nothing. It’s a private header and is only included in 1 TU.
In that fine, cxxabi-config is already included first

• msg-7316-56.txt162 BDownload

[erik.pilkington]

In D49575#1169729, @llvm-commits wrote:

Or just doing nothing. It’s a private header and is only included in 1 TU.
In that fine, cxxabi-config is already included first

I guess we're starting to split hairs here, but I think its better to make headers self-contained rather then implicitly relying on #include ordering, even for a one-off header like this.

libcxxabi/src/demangle/Compiler.h

23 ↗

(On Diff #156384)

No, that would be fine too.

[zturner]

Yea, it's fine either way. I was just looking at it from the perspective
of minimizing differences from the master copy in LLVM. Definitely having
headers be self-contained is worthy, but it comes at the (very small)
expense of adding an extra difference from the master copy. That said, I
don't feel strongly, so if you want me to add it, that's fine.

libcxxabi/trunk/src/cxa_demangle.cpp

 // FIXME: (possibly) incomplete list of features that clang mangles that this
 // file does not yet support:
 //   - C++ modules TS
 
 #define _LIBCPP_NO_EXCEPTIONS
 
 #include "__cxxabi_config.h"
 
-#include <vector>
-#include <algorithm>
-#include <numeric>
+#include "demangle/Compiler.h"
+#include "demangle/StringView.h"
+#include "demangle/Utility.h"
+
 #include <cassert>
+#include <cctype>
 #include <cstdio>
 #include <cstdlib>
 #include <cstring>
-#include <cctype>
+#include <numeric>
+#include <vector>
 
-#ifdef _MSC_VER
-// snprintf is implemented in VS 2015
-#if _MSC_VER < 1900
-#define snprintf _snprintf_s
-#endif
-#endif
-
-#ifndef NDEBUG
-#if __has_attribute(noinline) && __has_attribute(used)
-#define DUMP_METHOD __attribute__((noinline,used))
-#else
-#define DUMP_METHOD
-#endif
-#endif
 
 namespace {
 
-class StringView {
-  const char *First;
-  const char *Last;
-
-public:
-  template <size_t N>
-  StringView(const char (&Str)[N]) : First(Str), Last(Str + N - 1) {}
-  StringView(const char *First_, const char *Last_) : First(First_), Last(Last_) {}
-  StringView() : First(nullptr), Last(nullptr) {}
-
-  StringView substr(size_t From, size_t To) {
-    if (To >= size())
-      To = size() - 1;
-    if (From >= size())
-      From = size() - 1;
-    return StringView(First + From, First + To);
-  }
-
-  StringView dropFront(size_t N) const {
-    if (N >= size())
-      N = size() - 1;
-    return StringView(First + N, Last);
-  }
-
-  bool startsWith(StringView Str) const {
-    if (Str.size() > size())
-      return false;
-    return std::equal(Str.begin(), Str.end(), begin());
-  }
-
-  const char &operator[](size_t Idx) const { return *(begin() + Idx); }
-
-  const char *begin() const { return First; }
-  const char *end() const { return Last; }
-  size_t size() const { return static_cast<size_t>(Last - First); }
-  bool empty() const { return First == Last; }
-};
-
-bool operator==(const StringView &LHS, const StringView &RHS) {
-  return LHS.size() == RHS.size() &&
-         std::equal(LHS.begin(), LHS.end(), RHS.begin());
-}
-
-// Stream that AST nodes write their string representation into after the AST
-// has been parsed.
-class OutputStream {
-  char *Buffer;
-  size_t CurrentPosition;
-  size_t BufferCapacity;
-
-  // Ensure there is at least n more positions in buffer.
-  void grow(size_t N) {
-    if (N + CurrentPosition >= BufferCapacity) {
-      BufferCapacity *= 2;
-      if (BufferCapacity < N + CurrentPosition)
-        BufferCapacity = N + CurrentPosition;
-      Buffer = static_cast<char *>(std::realloc(Buffer, BufferCapacity));
-    }
-  }
-
-public:
-  OutputStream(char *StartBuf, size_t Size)
-      : Buffer(StartBuf), CurrentPosition(0), BufferCapacity(Size) {}
-  OutputStream() = default;
-  void reset(char *Buffer_, size_t BufferCapacity_) {
-    CurrentPosition = 0;
-    Buffer = Buffer_;
-    BufferCapacity = BufferCapacity_;
-  }
-
-  /// If a ParameterPackExpansion (or similar type) is encountered, the offset
-  /// into the pack that we're currently printing.
-  unsigned CurrentPackIndex = std::numeric_limits<unsigned>::max();
-  unsigned CurrentPackMax = std::numeric_limits<unsigned>::max();
-
-  OutputStream &operator+=(StringView R) {
-    size_t Size = R.size();
-    if (Size == 0)
-      return *this;
-    grow(Size);
-    memmove(Buffer + CurrentPosition, R.begin(), Size);
-    CurrentPosition += Size;
-    return *this;
-  }
-
-  OutputStream &operator+=(char C) {
-    grow(1);
-    Buffer[CurrentPosition++] = C;
-    return *this;
-  }
-
-  size_t getCurrentPosition() const { return CurrentPosition; }
-  void setCurrentPosition(size_t NewPos) { CurrentPosition = NewPos; }
-
-  char back() const {
-    return CurrentPosition ? Buffer[CurrentPosition - 1] : '\0';
-  }
-
-  bool empty() const { return CurrentPosition == 0; }
-
-  char *getBuffer() { return Buffer; }
-  char *getBufferEnd() { return Buffer + CurrentPosition - 1; }
-  size_t getBufferCapacity() { return BufferCapacity; }
-};
-
-template <class T>
-class SwapAndRestore {
-  T &Restore;
-  T OriginalValue;
-public:
-  SwapAndRestore(T& Restore_, T NewVal)
-      : Restore(Restore_), OriginalValue(Restore) {
-    Restore = std::move(NewVal);
-  }
-  ~SwapAndRestore() { Restore = std::move(OriginalValue); }
-
-  SwapAndRestore(const SwapAndRestore &) = delete;
-  SwapAndRestore &operator=(const SwapAndRestore &) = delete;
+enum : int {
+  demangle_unknown_error = -4,
+  demangle_invalid_args = -3,
+  demangle_invalid_mangled_name = -2,
+  demangle_memory_alloc_failure = -1,
+  demangle_success = 0,
 };
 
 // Base class of all AST nodes. The AST is built by the parser, then is
 // traversed by the printLeft/Right functions to produce a demangled string.
 class Node {
 public:
   enum Kind : unsigned char {
     KNodeArrayNode,
public:
   }
 
   // Print the "left" side of this Node into OutputStream.
   virtual void printLeft(OutputStream &) const = 0;
 
   // Print the "right". This distinction is necessary to represent C++ types
   // that appear on the RHS of their subtype, such as arrays or functions.
   // Since most types don't have such a component, provide a default
-  // implemenation.
+  // implementation.
   virtual void printRight(OutputStream &) const {}
 
   virtual StringView getBaseName() const { return StringView(); }
 
   // Silence compiler warnings, this dtor will never be called.
   virtual ~Node() = default;
 
 #ifndef NDEBUG
FunctionType(Node *Ret_, NodeArray Params_, Qualifiers CVQuals_,
              /*RHSComponentCache=*/Cache::Yes, /*ArrayCache=*/Cache::No,
              /*FunctionCache=*/Cache::Yes),
         Ret(Ret_), Params(Params_), CVQuals(CVQuals_), RefQual(RefQual_),
         ExceptionSpec(ExceptionSpec_) {}
 
   bool hasRHSComponentSlow(OutputStream &) const override { return true; }
   bool hasFunctionSlow(OutputStream &) const override { return true; }
 
-  // Handle C++'s ... quirky decl grammer by using the left & right
+  // Handle C++'s ... quirky decl grammar by using the left & right
   // distinction. Consider:
   //   int (*f(float))(char) {}
   // f is a function that takes a float and returns a pointer to a function
   // that takes a char and returns an int. If we're trying to print f, start
   // by printing out the return types's left, then print our parameters, then
   // finally print right of the return type.
   void printLeft(OutputStream &S) const override {
     Ret->printLeft(S);
public:
   void printRight(OutputStream &S) const override {
     initializePackExpansion(S);
     size_t Idx = S.CurrentPackIndex;
     if (Idx < Data.size())
       Data[Idx]->printRight(S);
   }
 };
 
-/// A variadic template argument. This node represents an occurance of
+/// A variadic template argument. This node represents an occurrence of
 /// J<something>E in some <template-args>. It isn't itself unexpanded, unless
 /// one of it's Elements is. The parser inserts a ParameterPack into the
 /// TemplateParams table if the <template-args> this pack belongs to apply to an
 /// <encoding>.
 class TemplateArgumentPack final : public Node {
   NodeArray Elements;
 public:
   TemplateArgumentPack(NodeArray Elements_)
public:
   }
 };
 
 struct Db {
   const char *First;
   const char *Last;
 
   // Name stack, this is used by the parser to hold temporary names that were
-  // parsed. The parser colapses multiple names into new nodes to construct
+  // parsed. The parser collapses multiple names into new nodes to construct
   // the AST. Once the parser is finished, names.size() == 1.
   PODSmallVector<Node *, 32> Names;
 
   // Substitution table. Itanium supports name substitutions as a means of
   // compression. The string "S42_" refers to the 44nd entry (base-36) in this
   // table.
   PODSmallVector<Node *, 32> Subs;
 
if (look() == 'I') {
     return make<NameWithTemplateArgs>(Oper, TA);
   }
   return Oper;
 }
 
 // <unresolved-name>
 //  extension        ::= srN <unresolved-type> [<template-args>] <unresolved-qualifier-level>* E <base-unresolved-name>
 //                   ::= [gs] <base-unresolved-name>                     # x or (with "gs") ::x
-//                   ::= [gs] sr <unresolved-qualifier-level>+ E <base-unresolved-name>  
+//                   ::= [gs] sr <unresolved-qualifier-level>+ E <base-unresolved-name>
 //                                                                       # A::x, N::y, A<T>::z; "gs" means leading "::"
 //                   ::= sr <unresolved-type> <base-unresolved-name>     # T::x / decltype(p)::x
 //  extension        ::= sr <unresolved-type> <template-args> <base-unresolved-name>
 //                                                                       # T::N::x /decltype(p)::N::x
 //  (ignored)        ::= srN <unresolved-type>  <unresolved-qualifier-level>+ E <base-unresolved-name>
 //
 // <unresolved-qualifier-level> ::= <simple-id>
 Node *Db::parseUnresolvedName() {
if (!consumeIf("sr")) {
     SoFar = parseBaseUnresolvedName();
     if (SoFar == nullptr)
       return nullptr;
     if (Global)
       SoFar = make<GlobalQualifiedName>(SoFar);
     return SoFar;
   }
 
-  // [gs] sr <unresolved-qualifier-level>+ E   <base-unresolved-name>  
+  // [gs] sr <unresolved-qualifier-level>+ E   <base-unresolved-name>
   if (std::isdigit(look())) {
     do {
       Node *Qual = parseSimpleId();
       if (Qual == nullptr)
         return nullptr;
       if (SoFar)
         SoFar = make<QualifiedName>(SoFar, Qual);
       else if (Global)
if (Buf == nullptr) {
     BufferSize = *N;
 
   S.reset(Buf, BufferSize);
   return false;
 }
 
 }  // unnamed namespace
 
-enum {
-  unknown_error = -4,
-  invalid_args = -3,
-  invalid_mangled_name = -2,
-  memory_alloc_failure = -1,
-  success = 0,
-};
-
 namespace __cxxabiv1 {
 extern "C" _LIBCXXABI_FUNC_VIS char *
 __cxa_demangle(const char *MangledName, char *Buf, size_t *N, int *Status) {
   if (MangledName == nullptr || (Buf != nullptr && N == nullptr)) {
     if (Status)
-      *Status = invalid_args;
+      *Status = demangle_invalid_args;
     return nullptr;
   }
 
-  int InternalStatus = success;
+  int InternalStatus = demangle_success;
   Db Parser(MangledName, MangledName + std::strlen(MangledName));
   OutputStream S;
 
   Node *AST = Parser.parse();
 
   if (AST == nullptr)
-    InternalStatus = invalid_mangled_name;
+    InternalStatus = demangle_invalid_mangled_name;
   else if (initializeOutputStream(Buf, N, S, 1024))
-    InternalStatus = memory_alloc_failure;
+    InternalStatus = demangle_memory_alloc_failure;
   else {
     assert(Parser.ForwardTemplateRefs.empty());
     AST->print(S);
     S += '\0';
     if (N != nullptr)
       *N = S.getCurrentPosition();
     Buf = S.getBuffer();
   }
 
   if (Status)
     *Status = InternalStatus;
-  return InternalStatus == success ? Buf : nullptr;
+  return InternalStatus == demangle_success ? Buf : nullptr;
 }
 }  // __cxxabiv1

libcxxabi/trunk/src/demangle/Compiler.h

+//===--- Compiler.h ---------------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+// This file is contains a subset of macros copied from
+// llvm/lib/Demangle/Compiler.h.
+//===----------------------------------------------------------------------===//
+
+#ifndef LIBCXX_DEMANGLE_COMPILER_H
+#define LIBCXX_DEMANGLE_COMPILER_H
+
+#ifdef _MSC_VER
+// snprintf is implemented in VS 2015
+#if _MSC_VER < 1900
+#define snprintf _snprintf_s
+#endif
+#endif
+
+#ifndef __has_attribute
+#define __has_attribute(x) 0
+#endif
+
+#ifndef NDEBUG
+#if __has_attribute(noinline) && __has_attribute(used)
+#define DUMP_METHOD __attribute__((noinline, used))
+#else
+#define DUMP_METHOD
+#endif
+#endif
+
+#endif

libcxxabi/trunk/src/demangle/StringView.h

+//===--- StringView.h -------------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//
+// This file is copied from llvm/lib/Demangle/StringView.h.
+//===----------------------------------------------------------------------===//
+
+#ifndef LIBCXX_DEMANGLE_STRINGVIEW_H
+#define LIBCXX_DEMANGLE_STRINGVIEW_H
+
+#include <algorithm>
+#include <cassert>
+#include <cstring>
+
+namespace {
+class StringView {
+  const char *First;
+  const char *Last;
+
+public:
+  template <size_t N>
+  StringView(const char (&Str)[N]) : First(Str), Last(Str + N - 1) {}
+  StringView(const char *First_, const char *Last_)
+      : First(First_), Last(Last_) {}
+  StringView(const char *First_, size_t Len)
+      : First(First_), Last(First_ + Len) {}
+  StringView(const char *Str) : First(Str), Last(Str + std::strlen(Str)) {}
+  StringView() : First(nullptr), Last(nullptr) {}
+
+  StringView substr(size_t From) const {
+    return StringView(begin() + From, size() - From);
+  }
+
+  StringView substr(size_t From, size_t To) const {
+    if (To >= size())
+      To = size() - 1;
+    if (From >= size())
+      From = size() - 1;
+    return StringView(First + From, First + To);
+  }
+
+  StringView dropFront(size_t N = 1) const {
+    if (N >= size())
+      N = size() - 1;
+    return StringView(First + N, Last);
+  }
+
+  char front() const {
+    assert(!empty());
+    return *begin();
+  }
+
+  char popFront() {
+    assert(!empty());
+    return *First++;
+  }
+
+  bool consumeFront(char C) {
+    if (!startsWith(C))
+      return false;
+    *this = dropFront(1);
+    return true;
+  }
+
+  bool consumeFront(StringView S) {
+    if (!startsWith(S))
+      return false;
+    *this = dropFront(S.size());
+    return true;
+  }
+
+  bool startsWith(char C) const { return !empty() && *begin() == C; }
+
+  bool startsWith(StringView Str) const {
+    if (Str.size() > size())
+      return false;
+    return std::equal(Str.begin(), Str.end(), begin());
+  }
+
+  const char &operator[](size_t Idx) const { return *(begin() + Idx); }
+
+  const char *begin() const { return First; }
+  const char *end() const { return Last; }
+  size_t size() const { return static_cast<size_t>(Last - First); }
+  bool empty() const { return First == Last; }
+};
+
+inline bool operator==(const StringView &LHS, const StringView &RHS) {
+  return LHS.size() == RHS.size() &&
+         std::equal(LHS.begin(), LHS.end(), RHS.begin());
+}
+} // namespace
+
+#endif

libcxxabi/trunk/src/demangle/Utility.h

+//===--- Utility.h ----------------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//
+// This file is copied from llvm/lib/Demangle/Utility.h.
+//===----------------------------------------------------------------------===//
+
+#ifndef LIBCXX_DEMANGLE_UTILITY_H
+#define LIBCXX_DEMANGLE_UTILITY_H
+
+#include "StringView.h"
+
+#include <cstdint>
+#include <cstdlib>
+#include <cstring>
+#include <iterator>
+#include <limits>
+
+namespace {
+// Stream that AST nodes write their string representation into after the AST
+// has been parsed.
+class OutputStream {
+  char *Buffer;
+  size_t CurrentPosition;
+  size_t BufferCapacity;
+
+  // Ensure there is at least n more positions in buffer.
+  void grow(size_t N) {
+    if (N + CurrentPosition >= BufferCapacity) {
+      BufferCapacity *= 2;
+      if (BufferCapacity < N + CurrentPosition)
+        BufferCapacity = N + CurrentPosition;
+      Buffer = static_cast<char *>(std::realloc(Buffer, BufferCapacity));
+    }
+  }
+
+  void writeUnsigned(uint64_t N, bool isNeg = false) {
+    // Handle special case...
+    if (N == 0) {
+      *this << '0';
+      return;
+    }
+
+    char Temp[21];
+    char *TempPtr = std::end(Temp);
+
+    while (N) {
+      *--TempPtr = '0' + char(N % 10);
+      N /= 10;
+    }
+
+    // Add negative sign...
+    if (isNeg)
+      *--TempPtr = '-';
+    this->operator<<(StringView(TempPtr, std::end(Temp)));
+  }
+
+public:
+  OutputStream(char *StartBuf, size_t Size)
+      : Buffer(StartBuf), CurrentPosition(0), BufferCapacity(Size) {}
+  OutputStream() = default;
+  void reset(char *Buffer_, size_t BufferCapacity_) {
+    CurrentPosition = 0;
+    Buffer = Buffer_;
+    BufferCapacity = BufferCapacity_;
+  }
+
+  /// Create an OutputStream from a buffer and a size.  If either of these are
+  /// null a buffer is allocated.
+  static OutputStream create(char *StartBuf, size_t *Size, size_t AllocSize) {
+    OutputStream Result;
+
+    if (!StartBuf || !Size) {
+      StartBuf = static_cast<char *>(std::malloc(AllocSize));
+      Size = &AllocSize;
+    }
+
+    Result.reset(StartBuf, *Size);
+    return Result;
+  }
+
+  /// If a ParameterPackExpansion (or similar type) is encountered, the offset
+  /// into the pack that we're currently printing.
+  unsigned CurrentPackIndex = std::numeric_limits<unsigned>::max();
+  unsigned CurrentPackMax = std::numeric_limits<unsigned>::max();
+
+  OutputStream &operator+=(StringView R) {
+    size_t Size = R.size();
+    if (Size == 0)
+      return *this;
+    grow(Size);
+    std::memmove(Buffer + CurrentPosition, R.begin(), Size);
+    CurrentPosition += Size;
+    return *this;
+  }
+
+  OutputStream &operator+=(char C) {
+    grow(1);
+    Buffer[CurrentPosition++] = C;
+    return *this;
+  }
+
+  OutputStream &operator<<(StringView R) { return (*this += R); }
+
+  OutputStream &operator<<(char C) { return (*this += C); }
+
+  OutputStream &operator<<(long long N) {
+    if (N < 0)
+      writeUnsigned(static_cast<unsigned long long>(-N), true);
+    else
+      writeUnsigned(static_cast<unsigned long long>(N));
+    return *this;
+  }
+
+  OutputStream &operator<<(unsigned long long N) {
+    writeUnsigned(N, false);
+    return *this;
+  }
+
+  OutputStream &operator<<(long N) {
+    return this->operator<<(static_cast<long long>(N));
+  }
+
+  OutputStream &operator<<(unsigned long N) {
+    return this->operator<<(static_cast<unsigned long long>(N));
+  }
+
+  OutputStream &operator<<(int N) {
+    return this->operator<<(static_cast<long long>(N));
+  }
+
+  OutputStream &operator<<(unsigned int N) {
+    return this->operator<<(static_cast<unsigned long long>(N));
+  }
+
+  size_t getCurrentPosition() const { return CurrentPosition; }
+  void setCurrentPosition(size_t NewPos) { CurrentPosition = NewPos; }
+
+  char back() const {
+    return CurrentPosition ? Buffer[CurrentPosition - 1] : '\0';
+  }
+
+  bool empty() const { return CurrentPosition == 0; }
+
+  char *getBuffer() { return Buffer; }
+  char *getBufferEnd() { return Buffer + CurrentPosition - 1; }
+  size_t getBufferCapacity() { return BufferCapacity; }
+};
+
+template <class T> class SwapAndRestore {
+  T &Restore;
+  T OriginalValue;
+  bool ShouldRestore = true;
+
+public:
+  SwapAndRestore(T &Restore_) : SwapAndRestore(Restore_, Restore_) {}
+
+  SwapAndRestore(T &Restore_, T NewVal)
+      : Restore(Restore_), OriginalValue(Restore) {
+    Restore = std::move(NewVal);
+  }
+  ~SwapAndRestore() {
+    if (ShouldRestore)
+      Restore = std::move(OriginalValue);
+  }
+
+  void shouldRestore(bool ShouldRestore_) { ShouldRestore = ShouldRestore_; }
+
+  void restoreNow(bool Force) {
+    if (!Force && !ShouldRestore)
+      return;
+
+    Restore = std::move(OriginalValue);
+    ShouldRestore = false;
+  }
+
+  SwapAndRestore(const SwapAndRestore &) = delete;
+  SwapAndRestore &operator=(const SwapAndRestore &) = delete;
+};
+
+} // namespace
+
+#endif