Subversion Repositories QNX 8.QNX8 LLVM/Clang compiler suite

//===--- Builtins.h - Builtin function header -------------------*- C++ -*-===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//===----------------------------------------------------------------------===//

///

/// \file

/// Defines enum values for all the target-independent builtin

/// functions.

///

//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_BASIC_BUILTINS_H

#define LLVM_CLANG_BASIC_BUILTINS_H

#include "llvm/ADT/ArrayRef.h"

#include "llvm/ADT/StringMap.h"

#include "llvm/ADT/StringRef.h"

#include <cstring>

// VC++ defines 'alloca' as an object-like macro, which interferes with our

// builtins.

#undef alloca

namespace clang {

class TargetInfo;

class IdentifierTable;

class LangOptions;

enum LanguageID : uint16_t {

  GNU_LANG = 0x1,            // builtin requires GNU mode.

  C_LANG = 0x2,              // builtin for c only.

  CXX_LANG = 0x4,            // builtin for cplusplus only.

  OBJC_LANG = 0x8,           // builtin for objective-c and objective-c++

  MS_LANG = 0x10,            // builtin requires MS mode.

  OMP_LANG = 0x20,           // builtin requires OpenMP.

  CUDA_LANG = 0x40,          // builtin requires CUDA.

  COR_LANG = 0x80,           // builtin requires use of 'fcoroutine-ts' option.

  OCL_GAS = 0x100,           // builtin requires OpenCL generic address space.

  OCL_PIPE = 0x200,          // builtin requires OpenCL pipe.

  OCL_DSE = 0x400,           // builtin requires OpenCL device side enqueue.

  ALL_OCL_LANGUAGES = 0x800, // builtin for OCL languages.

  HLSL_LANG = 0x1000,        // builtin requires HLSL.

  ALL_LANGUAGES = C_LANG | CXX_LANG | OBJC_LANG, // builtin for all languages.

  ALL_GNU_LANGUAGES = ALL_LANGUAGES | GNU_LANG,  // builtin requires GNU mode.

  ALL_MS_LANGUAGES = ALL_LANGUAGES | MS_LANG     // builtin requires MS mode.

};

struct HeaderDesc {

  enum HeaderID : uint16_t {

#define HEADER(ID, NAME) ID,

#include "clang/Basic/BuiltinHeaders.def"

#undef HEADER

  } ID;

  constexpr HeaderDesc(HeaderID ID) : ID(ID) {}

  const char *getName() const;

};

namespace Builtin {

enum ID {

  NotBuiltin  = 0,      // This is not a builtin function.

#define BUILTIN(ID, TYPE, ATTRS) BI##ID,

#include "clang/Basic/Builtins.def"

  FirstTSBuiltin

};

struct Info {

  llvm::StringLiteral Name;

  const char *Type, *Attributes;

  const char *Features;

  HeaderDesc Header;

  LanguageID Langs;

};

/// Holds information about both target-independent and

/// target-specific builtins, allowing easy queries by clients.

///

/// Builtins from an optional auxiliary target are stored in

/// AuxTSRecords. Their IDs are shifted up by TSRecords.size() and need to

/// be translated back with getAuxBuiltinID() before use.

class Context {

  llvm::ArrayRef<Info> TSRecords;

  llvm::ArrayRef<Info> AuxTSRecords;

public:

  Context() = default;

  /// Perform target-specific initialization

  /// \param AuxTarget Target info to incorporate builtins from. May be nullptr.

  void InitializeTarget(const TargetInfo &Target, const TargetInfo *AuxTarget);

  /// Mark the identifiers for all the builtins with their

  /// appropriate builtin ID # and mark any non-portable builtin identifiers as

  /// such.

  void initializeBuiltins(IdentifierTable &Table, const LangOptions& LangOpts);

  /// Return the identifier name for the specified builtin,

  /// e.g. "__builtin_abs".

  llvm::StringRef getName(unsigned ID) const { return getRecord(ID).Name; }

  /// Get the type descriptor string for the specified builtin.

  const char *getTypeString(unsigned ID) const {

    return getRecord(ID).Type;

  }

  /// Return true if this function is a target-specific builtin.

  bool isTSBuiltin(unsigned ID) const {

    return ID >= Builtin::FirstTSBuiltin;

  }

  /// Return true if this function has no side effects.

  bool isPure(unsigned ID) const {

    return strchr(getRecord(ID).Attributes, 'U') != nullptr;

  }

  /// Return true if this function has no side effects and doesn't

  /// read memory.

  bool isConst(unsigned ID) const {

    return strchr(getRecord(ID).Attributes, 'c') != nullptr;

  }

  /// Return true if we know this builtin never throws an exception.

  bool isNoThrow(unsigned ID) const {

    return strchr(getRecord(ID).Attributes, 'n') != nullptr;

  }

  /// Return true if we know this builtin never returns.

  bool isNoReturn(unsigned ID) const {

    return strchr(getRecord(ID).Attributes, 'r') != nullptr;

  }

  /// Return true if we know this builtin can return twice.

  bool isReturnsTwice(unsigned ID) const {

    return strchr(getRecord(ID).Attributes, 'j') != nullptr;

  }

  /// Returns true if this builtin does not perform the side-effects

  /// of its arguments.

  bool isUnevaluated(unsigned ID) const {

    return strchr(getRecord(ID).Attributes, 'u') != nullptr;

  }

  /// Return true if this is a builtin for a libc/libm function,

  /// with a "__builtin_" prefix (e.g. __builtin_abs).

  bool isLibFunction(unsigned ID) const {

    return strchr(getRecord(ID).Attributes, 'F') != nullptr;

  }

  /// Determines whether this builtin is a predefined libc/libm

  /// function, such as "malloc", where we know the signature a

  /// priori.

  /// In C, such functions behave as if they are predeclared,

  /// possibly with a warning on first use. In Objective-C and C++,

  /// they do not, but they are recognized as builtins once we see

  /// a declaration.

  bool isPredefinedLibFunction(unsigned ID) const {

    return strchr(getRecord(ID).Attributes, 'f') != nullptr;

  }

  /// Returns true if this builtin requires appropriate header in other

  /// compilers. In Clang it will work even without including it, but we can emit

  /// a warning about missing header.

  bool isHeaderDependentFunction(unsigned ID) const {

    return strchr(getRecord(ID).Attributes, 'h') != nullptr;

  }

  /// Determines whether this builtin is a predefined compiler-rt/libgcc

  /// function, such as "__clear_cache", where we know the signature a

  /// priori.

  bool isPredefinedRuntimeFunction(unsigned ID) const {

    return strchr(getRecord(ID).Attributes, 'i') != nullptr;

  }

  /// Determines whether this builtin is a C++ standard library function

  /// that lives in (possibly-versioned) namespace std, possibly a template

  /// specialization, where the signature is determined by the standard library

  /// declaration.

  bool isInStdNamespace(unsigned ID) const {

    return strchr(getRecord(ID).Attributes, 'z') != nullptr;

  }

  /// Determines whether this builtin can have its address taken with no

  /// special action required.

  bool isDirectlyAddressable(unsigned ID) const {

    // Most standard library functions can have their addresses taken. C++

    // standard library functions formally cannot in C++20 onwards, and when

    // we allow it, we need to ensure we instantiate a definition.

    return isPredefinedLibFunction(ID) && !isInStdNamespace(ID);

  }

  /// Determines whether this builtin has custom typechecking.

  bool hasCustomTypechecking(unsigned ID) const {

    return strchr(getRecord(ID).Attributes, 't') != nullptr;

  }

  /// Determines whether a declaration of this builtin should be recognized

  /// even if the type doesn't match the specified signature.

  bool allowTypeMismatch(unsigned ID) const {

    return strchr(getRecord(ID).Attributes, 'T') != nullptr ||

           hasCustomTypechecking(ID);

  }

  /// Determines whether this builtin has a result or any arguments which

  /// are pointer types.

  bool hasPtrArgsOrResult(unsigned ID) const {

    return strchr(getRecord(ID).Type, '*') != nullptr;

  }

  /// Return true if this builtin has a result or any arguments which are

  /// reference types.

  bool hasReferenceArgsOrResult(unsigned ID) const {

    return strchr(getRecord(ID).Type, '&') != nullptr ||

           strchr(getRecord(ID).Type, 'A') != nullptr;

  }

  /// If this is a library function that comes from a specific

  /// header, retrieve that header name.

  const char *getHeaderName(unsigned ID) const {

    return getRecord(ID).Header.getName();

  }

  /// Determine whether this builtin is like printf in its

  /// formatting rules and, if so, set the index to the format string

  /// argument and whether this function as a va_list argument.

  bool isPrintfLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg);

  /// Determine whether this builtin is like scanf in its

  /// formatting rules and, if so, set the index to the format string

  /// argument and whether this function as a va_list argument.

  bool isScanfLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg);

  /// Determine whether this builtin has callback behavior (see

  /// llvm::AbstractCallSites for details). If so, add the index to the

  /// callback callee argument and the callback payload arguments.

  bool performsCallback(unsigned ID,

                        llvm::SmallVectorImpl<int> &Encoding) const;

  /// Return true if this function has no side effects and doesn't

  /// read memory, except for possibly errno or raising FP exceptions.

  ///

  /// Such functions can be const when the MathErrno lang option and FP

  /// exceptions are disabled.

  bool isConstWithoutErrnoAndExceptions(unsigned ID) const {

    return strchr(getRecord(ID).Attributes, 'e') != nullptr;

  }

  bool isConstWithoutExceptions(unsigned ID) const {

    return strchr(getRecord(ID).Attributes, 'g') != nullptr;

  }

  const char *getRequiredFeatures(unsigned ID) const {

    return getRecord(ID).Features;

  }

  unsigned getRequiredVectorWidth(unsigned ID) const;

  /// Return true if builtin ID belongs to AuxTarget.

  bool isAuxBuiltinID(unsigned ID) const {

    return ID >= (Builtin::FirstTSBuiltin + TSRecords.size());

  }

  /// Return real builtin ID (i.e. ID it would have during compilation

  /// for AuxTarget).

  unsigned getAuxBuiltinID(unsigned ID) const { return ID - TSRecords.size(); }

  /// Returns true if this is a libc/libm function without the '__builtin_'

  /// prefix.

  static bool isBuiltinFunc(llvm::StringRef Name);

  /// Returns true if this is a builtin that can be redeclared.  Returns true

  /// for non-builtins.

  bool canBeRedeclared(unsigned ID) const;

  /// Return true if this function can be constant evaluated by Clang frontend.

  bool isConstantEvaluated(unsigned ID) const {

    return strchr(getRecord(ID).Attributes, 'E') != nullptr;

  }

private:

  const Info &getRecord(unsigned ID) const;

  /// Helper function for isPrintfLike and isScanfLike.

  bool isLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg,

              const char *Fmt) const;

};

/// Returns true if the required target features of a builtin function are

/// enabled.

/// \p TargetFeatureMap maps a target feature to true if it is enabled and

///    false if it is disabled.

bool evaluateRequiredTargetFeatures(

    llvm::StringRef RequiredFatures,

    const llvm::StringMap<bool> &TargetFetureMap);

} // namespace Builtin

/// Kinds of BuiltinTemplateDecl.

enum BuiltinTemplateKind : int {

  /// This names the __make_integer_seq BuiltinTemplateDecl.

  BTK__make_integer_seq,

  /// This names the __type_pack_element BuiltinTemplateDecl.

  BTK__type_pack_element

};

} // end namespace clang

#endif