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// Part of the Crubit project, under the Apache License v2.0 with LLVM
// Exceptions. See /LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#ifndef CRUBIT_NULLABILITY_VERIFICATION_POINTER_NULLABILITY_H_
#define CRUBIT_NULLABILITY_VERIFICATION_POINTER_NULLABILITY_H_
#include <utility>
#include "clang/AST/ASTContext.h"
#include "clang/AST/Expr.h"
#include "clang/Analysis/FlowSensitive/DataflowEnvironment.h"
#include "clang/Analysis/FlowSensitive/Value.h"
#include "clang/Basic/Specifiers.h"
namespace clang {
namespace tidy {
namespace nullability {
/// Returns the `NullabilityKind` corresponding to the nullability annotation on
/// `Type` if present. Otherwise, returns `NullabilityKind::Unspecified`.
NullabilityKind getNullabilityKind(QualType Type, ASTContext& Ctx);
/// Returns the `PointerValue` allocated to `PointerExpr` if available.
/// Otherwise, returns nullptr.
dataflow::PointerValue* getPointerValueFromExpr(
const Expr* PointerExpr, const dataflow::Environment& Env);
/// Returns the properties representing the nullness information of a pointer.
///
/// The first boolean indicates if the pointer's nullability is known.
/// The second boolean indicates if the pointer's value is not null.
std::pair<dataflow::AtomicBoolValue&, dataflow::AtomicBoolValue&>
getPointerNullState(const dataflow::PointerValue& PointerVal,
const dataflow::Environment& Env);
/// Sets the nullness properties on `PointerVal` if not already initialised.
///
/// The boolean properties may be constrained by specifying `KnownConstraint`
/// and `NotNullConstraint`. Otherwise, the properties are set to freshly
/// created atomic booleans.
void initPointerNullState(dataflow::PointerValue& PointerVal,
dataflow::Environment& Env,
dataflow::BoolValue* KnownConstraint = nullptr,
dataflow::BoolValue* NotNullConstraint = nullptr);
/// Sets the nullness properties on `PointerVal` representing a nullptr if not
/// already initialised.
///
/// `Known` is constrained to true, `NotNull` is constrained to false.
inline void initNullPointer(dataflow::PointerValue& PointerVal,
dataflow::Environment& Env) {
initPointerNullState(PointerVal, Env,
/*KnownConstraint=*/&Env.getBoolLiteralValue(true),
/*NotNullConstraint=*/&Env.getBoolLiteralValue(false));
}
/// Sets the nullness properties on `PointerVal` representing a pointer that is
/// not null if not already initialised.
///
/// `Known` is constrained to true, `NotNull` is constrained to true.
inline void initNotNullPointer(dataflow::PointerValue& PointerVal,
dataflow::Environment& Env) {
initPointerNullState(PointerVal, Env,
/*KnownConstraint=*/&Env.getBoolLiteralValue(true),
/*NotNullConstraint=*/&Env.getBoolLiteralValue(true));
}
/// Sets the nullness properties on `PointerVal` representing a pointer that is
/// nullable if not already initialised.
///
/// `Known` is constrained to true, `NotNull` is unconstrained.
inline void initNullablePointer(dataflow::PointerValue& PointerVal,
dataflow::Environment& Env) {
initPointerNullState(PointerVal, Env,
/*KnownConstraint=*/&Env.getBoolLiteralValue(true));
}
/// Sets the nullness properties on `PointerVal` representing a pointer with
/// unknown nullability if not already initialised.
///
/// `Known` is constrained to false, `NotNull` is unconstrained.
inline void initUnknownPointer(dataflow::PointerValue& PointerVal,
dataflow::Environment& Env) {
initPointerNullState(PointerVal, Env,
/*KnownConstraint=*/&Env.getBoolLiteralValue(false));
}
/// Returns true if there is evidence that `PointerVal` may hold a nullptr.
bool isNullable(const dataflow::PointerValue& PointerVal,
const dataflow::Environment& Env);
} // namespace nullability
} // namespace tidy
} // namespace clang
#endif // CRUBIT_NULLABILITY_VERIFICATION_POINTER_NULLABILITY_H_