LLVM 17.0.0git
Public Member Functions | List of all members
llvm::AbstractState Struct Referenceabstract

An interface to query the internal state of an abstract attribute. More...

#include "llvm/Transforms/IPO/Attributor.h"

Inheritance diagram for llvm::AbstractState:
Inheritance graph

Public Member Functions

virtual ~AbstractState ()=default
virtual bool isValidState () const =0
 Return if this abstract state is in a valid state.
virtual bool isAtFixpoint () const =0
 Return if this abstract state is fixed, thus does not need to be updated if information changes as it cannot change itself.
virtual ChangeStatus indicateOptimisticFixpoint ()=0
 Indicate that the abstract state should converge to the optimistic state.
virtual ChangeStatus indicatePessimisticFixpoint ()=0
 Indicate that the abstract state should converge to the pessimistic state.

Detailed Description

An interface to query the internal state of an abstract attribute.

The abstract state is a minimal interface that allows the Attributor to communicate with the abstract attributes about their internal state without enforcing or exposing implementation details, e.g., the (existence of an) underlying lattice.

It is sufficient to be able to query if a state is (1) valid or invalid, (2) at a fixpoint, and to indicate to the state that (3) an optimistic fixpoint was reached or (4) a pessimistic fixpoint was enforced.

All methods need to be implemented by the subclass. For the common use case, a single boolean state or a bit-encoded state, the BooleanState and {Inc,Dec,Bit}IntegerState classes are already provided. An abstract attribute can inherit from them to get the abstract state interface and additional methods to directly modify the state based if needed. See the class comments for help.

Definition at line 2425 of file Attributor.h.

Constructor & Destructor Documentation

◆ ~AbstractState()

virtual llvm::AbstractState::~AbstractState ( )

Member Function Documentation

◆ indicateOptimisticFixpoint()

virtual ChangeStatus llvm::AbstractState::indicateOptimisticFixpoint ( )
pure virtual

◆ indicatePessimisticFixpoint()

virtual ChangeStatus llvm::AbstractState::indicatePessimisticFixpoint ( )
pure virtual

◆ isAtFixpoint()

virtual bool llvm::AbstractState::isAtFixpoint ( ) const
pure virtual

◆ isValidState()

virtual bool llvm::AbstractState::isValidState ( ) const
pure virtual

The documentation for this struct was generated from the following file: