clang::interp::Context Class Reference

Holds all information required to evaluate constexpr code in a module. More...

#include "/work/as-worker-4/publish-doxygen-docs/llvm-project/clang/lib/AST/ByteCode/Context.h"

Public Member Functions
	Context (ASTContext &Ctx)
	Initialises the constexpr VM.
	~Context ()
	Cleans up the constexpr VM.
bool	isPotentialConstantExpr (const EvalSettings &Settings, const FunctionDecl *FD)
	Checks if a function is a potential constant expression.
void	isPotentialConstantExprUnevaluated (const EvalSettings &Settings, const Expr *E, const FunctionDecl *FD)
bool	evaluateAsRValue (const EvalSettings &Settings, const Expr *E, APValue &Result)
	Evaluates a toplevel expression as an rvalue.
bool	evaluate (const EvalSettings &Settings, const Expr *E, APValue &Result)
	Like evaluateAsRvalue(), but does no implicit lvalue-to-rvalue conversion.
bool	evaluateAsInitializer (const EvalSettings &Settings, const VarDecl *VD, const Expr *Init, APValue &Result)
	Evaluates a toplevel initializer.
void	registerRedecl (const VarDecl *VD, const APValue &V)
bool	evaluateDestruction (const EvalSettings &Settings, const VarDecl *VD, APValue Value)
	Evaluates the destruction of a variable.
bool	evaluateCharRange (const EvalSettings &Settings, const Expr *SizeExpr, const Expr *PtrExpr, APValue &Result)
bool	evaluateCharRange (const EvalSettings &Settings, const Expr *SizeExpr, const Expr *PtrExpr, std::string &Result)
bool	evaluateString (const EvalSettings &Settings, const Expr *E, std::string &Result)
	Evaluate.
std::optional< uint64_t >	evaluateStrlen (const EvalSettings &Settings, const Expr *E)
	Evalute.
std::optional< uint64_t >	tryEvaluateObjectSize (const EvalSettings &Settings, const Expr *E, unsigned Kind, bool IsDynamic)
	If.
std::optional< bool >	evaluateWithSubstitution (const EvalSettings &Settings, const FunctionDecl *Callee, ArrayRef< const Expr * > Args, const Expr *This, const Expr *Condition)
ASTContext &	getASTContext () const
	Returns the AST context.
const LangOptions &	getLangOpts () const
	Returns the language options.
unsigned	getCharBit () const
	Returns CHAR_BIT.
const llvm::fltSemantics &	getFloatSemantics (QualType T) const
	Return the floating-point semantics for T.
uint32_t	getBitWidth (QualType T) const
	Return the size of T in bits.
OptPrimType	classify (QualType T) const
	Classifies a type.
OptPrimType	classify (const Expr *E) const
	Classifies an expression.
bool	canClassify (QualType T) const
bool	canClassify (const Expr *E) const
const CXXMethodDecl *	getOverridingFunction (const CXXRecordDecl *DynamicDecl, const CXXRecordDecl *StaticDecl, const CXXMethodDecl *InitialFunction) const
const Function *	getOrCreateFunction (const FunctionDecl *FuncDecl)
const Function *	getOrCreateObjCBlock (const BlockExpr *E)
Program &	getProgram () const
	Returns the program. This is only needed for unittests.
unsigned	collectBaseOffset (const RecordDecl *BaseDecl, const RecordDecl *DerivedDecl) const
const Record *	getRecord (const RecordDecl *D) const
unsigned	getEvalID () const

Static Public Member Functions
static bool	shouldBeGloballyIndexed (const ValueDecl *VD)
	Returns whether we should create a global variable for the given ValueDecl.
static bool	isUnevaluatedBuiltin (unsigned ID)
	Unevaluated builtins don't get their arguments put on the stack automatically.

Friends
class	EvalIDScope

Detailed Description

Holds all information required to evaluate constexpr code in a module.

Definition at line 49 of file Context.h.

Constructor & Destructor Documentation

Context()

Context::Context ( ASTContext & Ctx )

explicit

Initialises the constexpr VM.

Definition at line 30 of file Context.cpp.

References Context().

Referenced by Context().

~Context()

Context::~Context ( )

default

Cleans up the constexpr VM.

References clang::Condition, clang::interp::Init(), clang::Result, clang::interp::This(), and V.

Member Function Documentation

canClassify() [1/2]

bool clang::interp::Context::canClassify ( const Expr * E ) const

inline

Definition at line 159 of file Context.h.

References canClassify(), clang::Expr::getType(), and clang::Expr::isGLValue().

canClassify() [2/2]

bool clang::interp::Context::canClassify ( QualType T ) const

inline

Definition at line 138 of file Context.h.

References classify(), and clang::T.

Referenced by canClassify(), getOrCreateFunction(), clang::interp::interp__builtin_strcmp(), and toRValue().

classify() [1/2]

OptPrimType clang::interp::Context::classify ( const Expr * E ) const

inline

Classifies an expression.

Definition at line 130 of file Context.h.

References classify(), clang::Expr::getType(), clang::Expr::isGLValue(), and clang::interp::PT_Ptr.

classify() [2/2]

OptPrimType Context::classify

(

QualType

T

)

const

Classifies a type.

Definition at line 521 of file Context.cpp.

References classify(), integralTypeToPrimTypeS(), integralTypeToPrimTypeU(), clang::interp::PT_Bool, clang::interp::PT_FixedPoint, clang::interp::PT_Float, clang::interp::PT_MemberPtr, clang::interp::PT_Ptr, clang::interp::PT_Reflect, and clang::T.

Referenced by clang::interp::CallPtr(), canClassify(), clang::interp::CheckNonNullArgs(), classify(), classify(), convertToBlockPointer(), enumerateData(), evaluateString(), evaluateWithSubstitution(), getOrCreateFunction(), getOrCreateObjCBlock(), clang::interp::interp__builtin_addressof(), clang::interp::interp__builtin_assume_aligned(), clang::interp::interp__builtin_carryop(), clang::interp::interp__builtin_elementwise_abs(), clang::interp::interp__builtin_elementwise_countzeroes(), clang::interp::interp__builtin_elementwise_int_binop(), clang::interp::interp__builtin_elementwise_int_unaryop(), clang::interp::interp__builtin_elementwise_maxmin(), clang::interp::interp__builtin_elementwise_triop(), clang::interp::interp__builtin_expect(), clang::interp::interp__builtin_fpclassify(), clang::interp::interp__builtin_ia32_addcarry_subborrow(), clang::interp::interp__builtin_ia32_dbpsadbw(), clang::interp::interp__builtin_ia32_gfni_affine(), clang::interp::interp__builtin_ia32_gfni_mul(), clang::interp::interp__builtin_ia32_movmsk_op(), clang::interp::interp__builtin_ia32_mpsadbw(), clang::interp::interp__builtin_ia32_multishiftqb(), clang::interp::interp__builtin_ia32_pack(), clang::interp::interp__builtin_ia32_pclmulqdq(), clang::interp::interp__builtin_ia32_phminposuw(), clang::interp::interp__builtin_ia32_pmul(), clang::interp::interp__builtin_ia32_psadbw(), clang::interp::interp__builtin_ia32_pternlog(), clang::interp::interp__builtin_ia32_shift_with_count(), clang::interp::interp__builtin_ia32_shufbitqmb_mask(), clang::interp::interp__builtin_ia32_shuffle_generic(), clang::interp::interp__builtin_ia32_test_op(), clang::interp::interp__builtin_ia32_vcvtps2ph(), clang::interp::interp__builtin_ia32_vpconflict(), clang::interp::interp__builtin_ia32_vpdp(), clang::interp::interp__builtin_infer_alloc_token(), clang::interp::interp__builtin_is_aligned_up_down(), clang::interp::interp__builtin_memchr(), clang::interp::interp__builtin_memcmp(), clang::interp::interp__builtin_operator_delete(), clang::interp::interp__builtin_operator_new(), clang::interp::interp__builtin_overflowop(), clang::interp::interp__builtin_stdc_memreverse8(), clang::interp::interp__builtin_strcmp(), clang::interp::interp__builtin_vector_reduce(), clang::interp::interp_builtin_horizontal_int_binop(), clang::interp::interp_builtin_ia32_cvt_vector_to_int(), clang::interp::popToAPSInt(), clang::interp::popToAPSInt(), clang::interp::popToUInt64(), clang::interp::pushInteger(), clang::interp::Pointer::toRValue(), and toRValue().

collectBaseOffset()

unsigned Context::collectBaseOffset	(	const RecordDecl *	BaseDecl,
		const RecordDecl *	DerivedDecl ) const

Definition at line 804 of file Context.cpp.

References clang::interp::Record::bases(), clang::cast(), and clang::interp::Record::getNumBases().

Referenced by clang::interp::CallVirt(), and clang::interp::MemberPointer::toPointer().

evaluate()

bool Context::evaluate	(	const EvalSettings &	Settings,
		const Expr *	E,
		APValue &	Result )

Like evaluateAsRvalue(), but does no implicit lvalue-to-rvalue conversion.

Definition at line 106 of file Context.cpp.

References clang::C, clang::interp::EvalSettings::ConstexprKind, and clang::Result.

Referenced by clang::Expr::EvaluateAsConstantExpr(), and clang::Expr::EvaluateAsLValue().

evaluateAsInitializer()

bool Context::evaluateAsInitializer	(	const EvalSettings &	Settings,
		const VarDecl *	VD,
		const Expr *	Init,
		APValue &	Result )

Evaluates a toplevel initializer.

Definition at line 137 of file Context.cpp.

References clang::C, clang::ValueDecl::getType(), clang::interp::Init(), clang::Type::isArrayType(), isRecordType(), and clang::Result.

Referenced by clang::Expr::EvaluateAsInitializer().

evaluateAsRValue()

bool Context::evaluateAsRValue	(	const EvalSettings &	Settings,
		const Expr *	E,
		APValue &	Result )

Evaluates a toplevel expression as an rvalue.

Definition at line 76 of file Context.cpp.

References clang::C, and clang::Result.

Referenced by CheckEvalInICE(), clang::Expr::EvaluateAsFixedPoint(), clang::Expr::EvaluateAsInt(), clang::Expr::EvaluateAsRValue(), clang::Expr::EvaluateForOverflow(), clang::Expr::EvaluateKnownConstInt(), clang::Expr::EvaluateKnownConstIntCheckOverflow(), clang::Expr::getIntegerConstantExpr(), and clang::Expr::isCXX11ConstantExpr().

evaluateCharRange() [1/2]

bool Context::evaluateCharRange	(	const EvalSettings &	Settings,
		const Expr *	SizeExpr,
		const Expr *	PtrExpr,
		APValue &	Result )

Definition at line 280 of file Context.cpp.

References clang::Result.

Referenced by EvaluateCharRangeAsStringImpl().

evaluateCharRange() [2/2]

bool Context::evaluateCharRange	(	const EvalSettings &	Settings,
		const Expr *	SizeExpr,
		const Expr *	PtrExpr,
		std::string &	Result )

Definition at line 289 of file Context.cpp.

References clang::Result.

evaluateDestruction()

bool Context::evaluateDestruction	(	const EvalSettings &	Settings,
		const VarDecl *	VD,
		APValue	Value )

Evaluates the destruction of a variable.

Definition at line 170 of file Context.cpp.

References clang::C.

Referenced by clang::VarDecl::evaluateDestruction().

evaluateString()

bool Context::evaluateString	(	const EvalSettings &	Settings,
		const Expr *	E,
		std::string &	Result )

Evaluate.

Parameters

E	and if it can be evaluated to a null-terminated string, copy the result into
Result.

Definition at line 298 of file Context.cpp.

References clang::C, classify(), INT_TYPE_SWITCH, clang::Result, and clang::T.

Referenced by clang::Expr::tryEvaluateString().

evaluateStrlen()

std::optional< uint64_t > Context::evaluateStrlen	(	const EvalSettings &	Settings,
		const Expr *	E )

Evalute.

Parameters

E	and if it can be evaluated to a string literal, run strlen() on it.

Definition at line 363 of file Context.cpp.

References clang::C, clang::interp::Descriptor::getPrimType(), INT_TYPE_SWITCH, clang::interp::isIntegerType(), clang::interp::Descriptor::isPrimitiveArray(), clang::Off, clang::Result, and clang::T.

Referenced by clang::Expr::tryEvaluateStrLen().

evaluateWithSubstitution()

std::optional< bool > Context::evaluateWithSubstitution	(	const EvalSettings &	Settings,
		const FunctionDecl *	Callee,
		ArrayRef< const Expr * >	Args,
		const Expr *	This,
		const Expr *	Condition )

Definition at line 461 of file Context.cpp.

References clang::C, classify(), clang::Condition, clang::interp::PT_Bool, clang::Result, and clang::interp::This().

Referenced by clang::Expr::EvaluateWithSubstitution().

getASTContext()

ASTContext & clang::interp::Context::getASTContext ( ) const

inline

Returns the AST context.

Definition at line 116 of file Context.h.

Referenced by clang::interp::IntPointer::atOffset(), clang::interp::IntPointer::baseCast(), enumerateData(), getOrCreateFunction(), clang::interp::GetTypeidPtr(), print(), clang::interp::readPointerToBuffer(), clang::interp::Pointer::toRValue(), toRValue(), and tryEvaluateObjectSize().

getBitWidth()

uint32_t clang::interp::Context::getBitWidth ( QualType T ) const

inline

Return the size of T in bits.

Definition at line 124 of file Context.h.

References clang::T.

getCharBit()

unsigned Context::getCharBit

(

)

const

Returns CHAR_BIT.

Definition at line 604 of file Context.cpp.

Referenced by convertToBlockPointer().

getEvalID()

unsigned clang::interp::Context::getEvalID ( ) const

inline

Definition at line 190 of file Context.h.

Referenced by convertToBlockPointer(), and clang::interp::interp__builtin_operator_new().

getFloatSemantics()

const llvm::fltSemantics & Context::getFloatSemantics

(

QualType

T

)

const

Return the floating-point semantics for T.

Simple wrapper around getFloatTypeSemantics() to make code a little shorter.

Definition at line 610 of file Context.cpp.

References clang::T.

getLangOpts()

const LangOptions & Context::getLangOpts

(

)

const

Returns the language options.

Definition at line 487 of file Context.cpp.

Referenced by clang::interp::interp__builtin_elementwise_triop_fp(), clang::interp::interp__builtin_ia32_addsub(), and clang::interp::interp_builtin_horizontal_fp_binop().

getOrCreateFunction()

const Function * Context::getOrCreateFunction

(

const FunctionDecl *

FuncDecl

)

Definition at line 669 of file Context.cpp.

References clang::interp::align(), canClassify(), classify(), clang::Func, clang::Type::getAs(), getASTContext(), clang::FunctionDecl::getNumParams(), clang::FieldDecl::getParent(), clang::FunctionDecl::getReturnType(), clang::ValueDecl::getType(), clang::isLambdaCallOperator(), clang::Type::isVoidType(), clang::FunctionDecl::param_begin(), clang::FunctionDecl::param_empty(), clang::FunctionDecl::parameters(), clang::interp::primSize(), clang::interp::PT_Ptr, and clang::T.

Referenced by clang::interp::CallVirt(), clang::interp::GetMemberPtrDecl(), isPotentialConstantExpr(), and clang::interp::runRecordDestructor().

getOrCreateObjCBlock()

const Function * Context::getOrCreateObjCBlock

(

const BlockExpr *

E

)

Definition at line 766 of file Context.cpp.

References clang::interp::align(), classify(), clang::Func, clang::BlockExpr::getBlockDecl(), clang::BlockDecl::hasCaptures(), clang::BlockDecl::parameters(), clang::interp::primSize(), clang::interp::PT_Ptr, and clang::T.

getOverridingFunction()

const CXXMethodDecl * Context::getOverridingFunction	(	const CXXRecordDecl *	DynamicDecl,
		const CXXRecordDecl *	StaticDecl,
		const CXXMethodDecl *	InitialFunction ) const

Definition at line 633 of file Context.cpp.

References clang::CXXRecordDecl::bases(), clang::CXXRecordDecl::bases_begin(), clang::Type::getAsCXXRecordDecl(), clang::CXXMethodDecl::getCorrespondingMethodDeclaredInClass(), clang::CXXRecordDecl::getNumBases(), and clang::CXXBaseSpecifier::getType().

Referenced by clang::interp::CallVirt().

getProgram()

Program & clang::interp::Context::getProgram ( ) const

inline

Returns the program. This is only needed for unittests.

Definition at line 183 of file Context.h.

getRecord()

const Record * Context::getRecord

(

const RecordDecl *

D

)

const

Definition at line 835 of file Context.cpp.

Referenced by clang::interp::IntPointer::atOffset(), clang::interp::IntPointer::baseCast(), clang::interp::diagnoseTypeIdField(), clang::interp::getBase(), clang::interp::getField(), and clang::interp::MemberPointer::toPointer().

isPotentialConstantExpr()

bool Context::isPotentialConstantExpr	(	const EvalSettings &	Settings,
		const FunctionDecl *	FD )

Checks if a function is a potential constant expression.

Definition at line 41 of file Context.cpp.

References clang::Func, and getOrCreateFunction().

isPotentialConstantExprUnevaluated()

void Context::isPotentialConstantExprUnevaluated	(	const EvalSettings &	Settings,
		const Expr *	E,
		const FunctionDecl *	FD )

Definition at line 62 of file Context.cpp.

References clang::C.

Referenced by clang::Expr::isPotentialConstantExprUnevaluated().

isUnevaluatedBuiltin()

bool Context::isUnevaluatedBuiltin ( unsigned ID )

static

Unevaluated builtins don't get their arguments put on the stack automatically.

They instead operate on the AST of their Call Expression. Similar information is available via ASTContext::BuiltinInfo, but that is not correct for our use cases.

Definition at line 839 of file Context.cpp.

Referenced by clang::interp::Compiler< Emitter >::VisitBuiltinCallExpr().

registerRedecl()

void Context::registerRedecl	(	const VarDecl *	VD,
		const APValue &	V )

Definition at line 188 of file Context.cpp.

References clang::C, and V.

shouldBeGloballyIndexed()

bool clang::interp::Context::shouldBeGloballyIndexed ( const ValueDecl * VD )

inlinestatic

Returns whether we should create a global variable for the given ValueDecl.

Definition at line 175 of file Context.h.

References V.

Referenced by clang::interp::Program::createGlobal(), clang::interp::Compiler< Emitter >::VisitCastExpr(), clang::interp::Compiler< Emitter >::visitDecl(), clang::interp::Compiler< Emitter >::visitDeclAndReturn(), clang::interp::Compiler< Emitter >::VisitMaterializeTemporaryExpr(), and clang::interp::Compiler< Emitter >::visitVarDecl().

tryEvaluateObjectSize()

std::optional< uint64_t > Context::tryEvaluateObjectSize	(	const EvalSettings &	Settings,
		const Expr *	E,
		unsigned	Kind,
		bool	IsDynamic )

If.

Parameters

E

evaluates to a pointer the number of accessible bytes past the pointer is estimated in

Result

as if evaluated by the builtin function __builtin_object_size. This is a best effort approximation, when Kind & 2 == 0 the object size is less than or equal to the estimated size, when Kind & 2 == 1 the true value is greater than or equal to the estimated size. When Kind & 1 == 1 only bytes belonging to the same subobject as the one referred to by E are considered, when Kind & 1 == 0 bytes belonging to the same storage (stack, heap allocation, global variable) are considered.

Definition at line 431 of file Context.cpp.

References clang::C, clang::interp::evaluateBuiltinObjectSize(), getASTContext(), clang::Result, and clang::T.

Referenced by clang::Expr::tryEvaluateObjectSize().

Friends And Related Symbol Documentation

EvalIDScope

friend class EvalIDScope

friend

Definition at line 200 of file Context.h.

References EvalIDScope, clang::Func, and clang::Result.

Referenced by EvalIDScope.

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The documentation for this class was generated from the following files:

• lib/AST/ByteCode/Context.h
• lib/AST/ByteCode/Context.cpp