clang-1/include/clang/Sema/ScopeInfo.h

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//===--- ScopeInfo.h - Information about a semantic context -----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines FunctionScopeInfo and BlockScopeInfo.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CLANG_SEMA_SCOPE_INFO_H
#define LLVM_CLANG_SEMA_SCOPE_INFO_H
#include "clang/AST/Type.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallVector.h"
namespace clang {
class BlockDecl;
class IdentifierInfo;
class LabelStmt;
class ReturnStmt;
class Scope;
class SwitchStmt;
namespace sema {
/// \brief Retains information about a function, method, or block that is
/// currently being parsed.
class FunctionScopeInfo {
public:
/// \brief Whether this scope information structure defined information for
/// a block.
bool IsBlockInfo;
/// \brief Whether this function contains a VLA, @try, try, C++
/// initializer, or anything else that can't be jumped past.
bool HasBranchProtectedScope;
/// \brief Whether this function contains any switches or direct gotos.
bool HasBranchIntoScope;
/// \brief Whether this function contains any indirect gotos.
bool HasIndirectGoto;
/// \brief The number of errors that had occurred before starting this
/// function or block.
unsigned NumErrorsAtStartOfFunction;
/// LabelMap - This is a mapping from label identifiers to the LabelStmt for
/// it (which acts like the label decl in some ways). Forward referenced
/// labels have a LabelStmt created for them with a null location & SubStmt.
llvm::DenseMap<IdentifierInfo*, LabelStmt*> LabelMap;
/// SwitchStack - This is the current set of active switch statements in the
/// block.
llvm::SmallVector<SwitchStmt*, 8> SwitchStack;
/// \brief The list of return statements that occur within the function or
/// block, if there is any chance of applying the named return value
/// optimization.
llvm::SmallVector<ReturnStmt *, 4> Returns;
void setHasBranchIntoScope() {
HasBranchIntoScope = true;
}
void setHasBranchProtectedScope() {
HasBranchProtectedScope = true;
}
void setHasIndirectGoto() {
HasIndirectGoto = true;
}
bool NeedsScopeChecking() const {
return HasIndirectGoto ||
(HasBranchProtectedScope && HasBranchIntoScope);
}
FunctionScopeInfo(unsigned NumErrors)
: IsBlockInfo(false),
HasBranchProtectedScope(false),
HasBranchIntoScope(false),
HasIndirectGoto(false),
NumErrorsAtStartOfFunction(NumErrors) { }
virtual ~FunctionScopeInfo();
/// \brief Clear out the information in this function scope, making it
/// suitable for reuse.
void Clear(unsigned NumErrors);
static bool classof(const FunctionScopeInfo *FSI) { return true; }
};
/// \brief Retains information about a block that is currently being parsed.
class BlockScopeInfo : public FunctionScopeInfo {
public:
bool hasBlockDeclRefExprs;
BlockDecl *TheDecl;
/// TheScope - This is the scope for the block itself, which contains
/// arguments etc.
Scope *TheScope;
/// ReturnType - The return type of the block, or null if the block
/// signature didn't provide an explicit return type.
QualType ReturnType;
/// BlockType - The function type of the block, if one was given.
/// Its return type may be BuiltinType::Dependent.
QualType FunctionType;
BlockScopeInfo(unsigned NumErrors, Scope *BlockScope, BlockDecl *Block)
: FunctionScopeInfo(NumErrors), hasBlockDeclRefExprs(false),
TheDecl(Block), TheScope(BlockScope)
{
IsBlockInfo = true;
}
virtual ~BlockScopeInfo();
static bool classof(const FunctionScopeInfo *FSI) { return FSI->IsBlockInfo; }
static bool classof(const BlockScopeInfo *BSI) { return true; }
};
}
}
#endif