C++ llvm::utostr方法代码示例

std::string RewriteBlocks::SynthesizeBlockHelperFuncs(BlockExpr *CE, int i,
                                                   const char *funcName,
                                                   std::string Tag) {
  std::string StructRef = "struct " + Tag;
  std::string S = "static void __";
  
  S += funcName;
  S += "_block_copy_" + utostr(i);
  S += "(" + StructRef;
  S += "*dst, " + StructRef;
  S += "*src) {";
  for (llvm::SmallPtrSet<ValueDecl*,8>::iterator I = ImportedBlockDecls.begin(), 
      E = ImportedBlockDecls.end(); I != E; ++I) {
    S += "_Block_copy_assign(&dst->";
    S += (*I)->getNameAsString();
    S += ", src->";
    S += (*I)->getNameAsString();
    S += ");}";
  }
  S += "\nstatic void __";
  S += funcName;
  S += "_block_dispose_" + utostr(i);
  S += "(" + StructRef;
  S += "*src) {";
  for (llvm::SmallPtrSet<ValueDecl*,8>::iterator I = ImportedBlockDecls.begin(), 
      E = ImportedBlockDecls.end(); I != E; ++I) {
    S += "_Block_destroy(src->";
    S += (*I)->getNameAsString();
    S += ");";
  }
  S += "}\n";  
  return S;
}

void RewriteBlocks::SynthesizeBlockLiterals(SourceLocation FunLocStart,
                                                const char *FunName) {
  // Insert closures that were part of the function.
  for (unsigned i = 0; i < Blocks.size(); i++) {

    CollectBlockDeclRefInfo(Blocks[i]);

    std::string Tag = "__" + std::string(FunName) + "_block_impl_" + utostr(i);
                      
    std::string CI = SynthesizeBlockImpl(Blocks[i], Tag, 
                                         ImportedBlockDecls.size() > 0);

    InsertText(FunLocStart, CI.c_str(), CI.size());

    std::string CF = SynthesizeBlockFunc(Blocks[i], i, FunName, Tag);
    
    InsertText(FunLocStart, CF.c_str(), CF.size());

    if (ImportedBlockDecls.size()) {
      std::string HF = SynthesizeBlockHelperFuncs(Blocks[i], i, FunName, Tag);
      InsertText(FunLocStart, HF.c_str(), HF.size());
    }
    
    BlockDeclRefs.clear();
    BlockByRefDecls.clear();
    BlockByCopyDecls.clear();
    BlockCallExprs.clear();
    ImportedBlockDecls.clear();
  }
  Blocks.clear();
  RewrittenBlockExprs.clear();
}

std::string RewriteBlocks::SynthesizeBlockInitExpr(BlockExpr *Exp, VarDecl *VD) {
  Blocks.push_back(Exp);

  CollectBlockDeclRefInfo(Exp);
  std::string FuncName;
  
  if (CurFunctionDef)
    FuncName = std::string(CurFunctionDef->getNameAsString());
  else if (CurMethodDef) {
    FuncName = CurMethodDef->getSelector().getAsString();
    // Convert colons to underscores.
    std::string::size_type loc = 0;
    while ((loc = FuncName.find(":", loc)) != std::string::npos)
      FuncName.replace(loc, 1, "_");
  } else if (VD)
    FuncName = std::string(VD->getNameAsString());
    
  std::string BlockNumber = utostr(Blocks.size()-1);
  
  std::string Tag = "__" + FuncName + "_block_impl_" + BlockNumber;
  std::string Func = "__" + FuncName + "_block_func_" + BlockNumber;
  
  std::string FunkTypeStr;
  
  // Get a pointer to the function type so we can cast appropriately.
  Context->getPointerType(QualType(Exp->getFunctionType(),0)).getAsStringInternal(FunkTypeStr);
  
  // Rewrite the closure block with a compound literal. The first cast is
  // to prevent warnings from the C compiler.
  std::string Init = "(" + FunkTypeStr;
  
  Init += ")&" + Tag;
  
  // Initialize the block function.
  Init += "((void*)" + Func;
  
  if (ImportedBlockDecls.size()) {
    std::string Buf = "__" + FuncName + "_block_copy_" + BlockNumber;
    Init += ",(void*)" + Buf;
    Buf = "__" + FuncName + "_block_dispose_" + BlockNumber;
    Init += ",(void*)" + Buf;
  }
  // Add initializers for any closure decl refs.
  if (BlockDeclRefs.size()) {
    // Output all "by copy" declarations.
    for (llvm::SmallPtrSet<ValueDecl*,8>::iterator I = BlockByCopyDecls.begin(), 
         E = BlockByCopyDecls.end(); I != E; ++I) {
      Init += ",";
      if (isObjCType((*I)->getType())) {
        Init += "[[";
        Init += (*I)->getNameAsString();
        Init += " retain] autorelease]";
      } else if (isBlockPointerType((*I)->getType())) {
        Init += "(void *)";
        Init += (*I)->getNameAsString();
      } else {
        Init += (*I)->getNameAsString();
      }
    }
    // Output all "by ref" declarations.
    for (llvm::SmallPtrSet<ValueDecl*,8>::iterator I = BlockByRefDecls.begin(), 
         E = BlockByRefDecls.end(); I != E; ++I) {
      Init += ",&";
      Init += (*I)->getNameAsString();
    }
  }
  Init += ")";
  BlockDeclRefs.clear();
  BlockByRefDecls.clear();
  BlockByCopyDecls.clear();
  ImportedBlockDecls.clear();

  return Init;
}

std::string RewriteBlocks::SynthesizeBlockFunc(BlockExpr *CE, int i,
                                                   const char *funcName,
                                                   std::string Tag) {
  const FunctionType *AFT = CE->getFunctionType();
  QualType RT = AFT->getResultType();
  std::string StructRef = "struct " + Tag;
  std::string S = "static " + RT.getAsString() + " __" +
                  funcName + "_" + "block_func_" + utostr(i);

  BlockDecl *BD = CE->getBlockDecl();
  
  if (isa<FunctionNoProtoType>(AFT)) {
    S += "()";
  } else if (BD->param_empty()) {
    S += "(" + StructRef + " *__cself)";
  } else {
    const FunctionProtoType *FT = cast<FunctionProtoType>(AFT);
    assert(FT && "SynthesizeBlockFunc: No function proto");
    S += '(';
    // first add the implicit argument.
    S += StructRef + " *__cself, ";
    std::string ParamStr;
    for (BlockDecl::param_iterator AI = BD->param_begin(),
         E = BD->param_end(); AI != E; ++AI) {
      if (AI != BD->param_begin()) S += ", ";
      ParamStr = (*AI)->getNameAsString();
      (*AI)->getType().getAsStringInternal(ParamStr);
      S += ParamStr;
    }
    if (FT->isVariadic()) {
      if (!BD->param_empty()) S += ", ";
      S += "...";
    }
    S += ')';
  }
  S += " {\n";
  
  // Create local declarations to avoid rewriting all closure decl ref exprs.
  // First, emit a declaration for all "by ref" decls.
  for (llvm::SmallPtrSet<ValueDecl*,8>::iterator I = BlockByRefDecls.begin(), 
       E = BlockByRefDecls.end(); I != E; ++I) {
    S += "  ";
    std::string Name = (*I)->getNameAsString();
    Context->getPointerType((*I)->getType()).getAsStringInternal(Name);
    S += Name + " = __cself->" + (*I)->getNameAsString() + "; // bound by ref\n";
  }    
  // Next, emit a declaration for all "by copy" declarations.
  for (llvm::SmallPtrSet<ValueDecl*,8>::iterator I = BlockByCopyDecls.begin(), 
       E = BlockByCopyDecls.end(); I != E; ++I) {
    S += "  ";
    std::string Name = (*I)->getNameAsString();
    // Handle nested closure invocation. For example:
    //
    //   void (^myImportedClosure)(void);
    //   myImportedClosure  = ^(void) { setGlobalInt(x + y); };
    // 
    //   void (^anotherClosure)(void);
    //   anotherClosure = ^(void) {
    //     myImportedClosure(); // import and invoke the closure
    //   };
    //
    if (isBlockPointerType((*I)->getType()))
      S += "struct __block_impl *";
    else
      (*I)->getType().getAsStringInternal(Name);
    S += Name + " = __cself->" + (*I)->getNameAsString() + "; // bound by copy\n";
  }
  std::string RewrittenStr = RewrittenBlockExprs[CE];
  const char *cstr = RewrittenStr.c_str();
  while (*cstr++ != '{') ;
  S += cstr;
  S += "\n";
  return S;
}