Viewing file:  SemaBase.h (8.26 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
//===--- SemaBase.h - Common utilities for semantic analysis-----*- 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
//
//===----------------------------------------------------------------------===//
//
// This file defines the SemaBase class, which provides utilities for Sema
// and its parts like SemaOpenACC.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CLANG_SEMA_SEMABASE_H
#define LLVM_CLANG_SEMA_SEMABASE_H
#include "clang/AST/Decl.h"
#include "clang/AST/Redeclarable.h"
#include "clang/Basic/Diagnostic.h"
#include "clang/Basic/PartialDiagnostic.h"
#include "clang/Basic/SourceLocation.h"
#include "clang/Sema/Ownership.h"
#include "llvm/ADT/DenseMap.h"
#include <optional>
#include <type_traits>
#include <utility>
#include <vector>
namespace clang {
class ASTContext;
class DiagnosticsEngine;
class LangOptions;
class Sema;
class SemaBase {
public:
SemaBase(Sema &S);
Sema &SemaRef;
ASTContext &getASTContext() const;
DiagnosticsEngine &getDiagnostics() const;
const LangOptions &getLangOpts() const;
/// Helper class that creates diagnostics with optional
/// template instantiation stacks.
///
/// This class provides a wrapper around the basic DiagnosticBuilder
/// class that emits diagnostics. ImmediateDiagBuilder is
/// responsible for emitting the diagnostic (as DiagnosticBuilder
/// does) and, if the diagnostic comes from inside a template
/// instantiation, printing the template instantiation stack as
/// well.
class ImmediateDiagBuilder : public DiagnosticBuilder {
Sema &SemaRef;
unsigned DiagID;
public:
ImmediateDiagBuilder(DiagnosticBuilder &DB, Sema &SemaRef, unsigned DiagID)
: DiagnosticBuilder(DB), SemaRef(SemaRef), DiagID(DiagID) {}
ImmediateDiagBuilder(DiagnosticBuilder &&DB, Sema &SemaRef, unsigned DiagID)
: DiagnosticBuilder(DB), SemaRef(SemaRef), DiagID(DiagID) {}
// This is a cunning lie. DiagnosticBuilder actually performs move
// construction in its copy constructor (but due to varied uses, it's not
// possible to conveniently express this as actual move construction). So
// the default copy ctor here is fine, because the base class disables the
// source anyway, so the user-defined ~ImmediateDiagBuilder is a safe no-op
// in that case anwyay.
ImmediateDiagBuilder(const ImmediateDiagBuilder &) = default;
~ImmediateDiagBuilder();
/// Teach operator<< to produce an object of the correct type.
template <typename T>
friend const ImmediateDiagBuilder &
operator<<(const ImmediateDiagBuilder &Diag, const T &Value) {
const DiagnosticBuilder &BaseDiag = Diag;
BaseDiag << Value;
return Diag;
}
// It is necessary to limit this to rvalue reference to avoid calling this
// function with a bitfield lvalue argument since non-const reference to
// bitfield is not allowed.
template <typename T,
typename = std::enable_if_t<!std::is_lvalue_reference<T>::value>>
const ImmediateDiagBuilder &operator<<(T &&V) const {
const DiagnosticBuilder &BaseDiag = *this;
BaseDiag << std::move(V);
return *this;
}
};
/// A generic diagnostic builder for errors which may or may not be deferred.
///
/// In CUDA, there exist constructs (e.g. variable-length arrays, try/catch)
/// which are not allowed to appear inside __device__ functions and are
/// allowed to appear in __host__ __device__ functions only if the host+device
/// function is never codegen'ed.
///
/// To handle this, we use the notion of "deferred diagnostics", where we
/// attach a diagnostic to a FunctionDecl that's emitted iff it's codegen'ed.
///
/// This class lets you emit either a regular diagnostic, a deferred
/// diagnostic, or no diagnostic at all, according to an argument you pass to
/// its constructor, thus simplifying the process of creating these "maybe
/// deferred" diagnostics.
class SemaDiagnosticBuilder {
public:
enum Kind {
/// Emit no diagnostics.
K_Nop,
/// Emit the diagnostic immediately (i.e., behave like Sema::Diag()).
K_Immediate,
/// Emit the diagnostic immediately, and, if it's a warning or error, also
/// emit a call stack showing how this function can be reached by an a
/// priori known-emitted function.
K_ImmediateWithCallStack,
/// Create a deferred diagnostic, which is emitted only if the function
/// it's attached to is codegen'ed. Also emit a call stack as with
/// K_ImmediateWithCallStack.
K_Deferred
};
SemaDiagnosticBuilder(Kind K, SourceLocation Loc, unsigned DiagID,
const FunctionDecl *Fn, Sema &S);
SemaDiagnosticBuilder(SemaDiagnosticBuilder &&D);
SemaDiagnosticBuilder(const SemaDiagnosticBuilder &) = default;
// The copy and move assignment operator is defined as deleted pending
// further motivation.
SemaDiagnosticBuilder &operator=(const SemaDiagnosticBuilder &) = delete;
SemaDiagnosticBuilder &operator=(SemaDiagnosticBuilder &&) = delete;
~SemaDiagnosticBuilder();
bool isImmediate() const { return ImmediateDiag.has_value(); }
/// Convertible to bool: True if we immediately emitted an error, false if
/// we didn't emit an error or we created a deferred error.
///
/// Example usage:
///
/// if (SemaDiagnosticBuilder(...) << foo << bar)
/// return ExprError();
///
/// But see DiagIfDeviceCode() and DiagIfHostCode() -- you probably
/// want to use these instead of creating a SemaDiagnosticBuilder yourself.
operator bool() const { return isImmediate(); }
template <typename T>
friend const SemaDiagnosticBuilder &
operator<<(const SemaDiagnosticBuilder &Diag, const T &Value) {
if (Diag.ImmediateDiag)
*Diag.ImmediateDiag << Value;
else if (Diag.PartialDiagId)
Diag.getDeviceDeferredDiags()[Diag.Fn][*Diag.PartialDiagId].second
<< Value;
return Diag;
}
// It is necessary to limit this to rvalue reference to avoid calling this
// function with a bitfield lvalue argument since non-const reference to
// bitfield is not allowed.
template <typename T,
typename = std::enable_if_t<!std::is_lvalue_reference<T>::value>>
const SemaDiagnosticBuilder &operator<<(T &&V) const {
if (ImmediateDiag)
*ImmediateDiag << std::move(V);
else if (PartialDiagId)
getDeviceDeferredDiags()[Fn][*PartialDiagId].second << std::move(V);
return *this;
}
friend const SemaDiagnosticBuilder &
operator<<(const SemaDiagnosticBuilder &Diag, const PartialDiagnostic &PD);
void AddFixItHint(const FixItHint &Hint) const;
friend ExprResult ExprError(const SemaDiagnosticBuilder &) {
return ExprError();
}
friend StmtResult StmtError(const SemaDiagnosticBuilder &) {
return StmtError();
}
operator ExprResult() const { return ExprError(); }
operator StmtResult() const { return StmtError(); }
operator TypeResult() const { return TypeError(); }
operator DeclResult() const { return DeclResult(true); }
operator MemInitResult() const { return MemInitResult(true); }
using DeferredDiagnosticsType =
llvm::DenseMap<CanonicalDeclPtr<const FunctionDecl>,
std::vector<PartialDiagnosticAt>>;
private:
Sema &S;
SourceLocation Loc;
unsigned DiagID;
const FunctionDecl *Fn;
bool ShowCallStack;
// Invariant: At most one of these Optionals has a value.
// FIXME: Switch these to a Variant once that exists.
std::optional<ImmediateDiagBuilder> ImmediateDiag;
std::optional<unsigned> PartialDiagId;
DeferredDiagnosticsType &getDeviceDeferredDiags() const;
};
/// Emit a diagnostic.
SemaDiagnosticBuilder Diag(SourceLocation Loc, unsigned DiagID,
bool DeferHint = false);
/// Emit a partial diagnostic.
SemaDiagnosticBuilder Diag(SourceLocation Loc, const PartialDiagnostic &PD,
bool DeferHint = false);
/// Build a partial diagnostic.
PartialDiagnostic PDiag(unsigned DiagID = 0);
};
} // namespace clang
#endif
|