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//===--- Interp.h - Interpreter for the constexpr VM ------------*- 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
//
//===----------------------------------------------------------------------===//
//
// Definition of the interpreter state and entry point.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CLANG_AST_INTERP_INTERP_H
#define LLVM_CLANG_AST_INTERP_INTERP_H
#include "../ExprConstShared.h"
#include "Boolean.h"
#include "DynamicAllocator.h"
#include "Floating.h"
#include "Function.h"
#include "FunctionPointer.h"
#include "InterpFrame.h"
#include "InterpStack.h"
#include "InterpState.h"
#include "MemberPointer.h"
#include "Opcode.h"
#include "PrimType.h"
#include "Program.h"
#include "State.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/Expr.h"
#include "llvm/ADT/APFloat.h"
#include "llvm/ADT/APSInt.h"
#include <type_traits>
namespace clang {
namespace interp {
using APSInt = llvm::APSInt;
/// Convert a value to an APValue.
template <typename T>
bool ReturnValue(const InterpState &S, const T &V, APValue &R) {
R = V.toAPValue(S.getCtx());
return true;
}
/// Checks if the variable has externally defined storage.
bool CheckExtern(InterpState &S, CodePtr OpPC, const Pointer &Ptr);
/// Checks if the array is offsetable.
bool CheckArray(InterpState &S, CodePtr OpPC, const Pointer &Ptr);
/// Checks if a pointer is live and accessible.
bool CheckLive(InterpState &S, CodePtr OpPC, const Pointer &Ptr,
AccessKinds AK);
/// Checks if a pointer is a dummy pointer.
bool CheckDummy(InterpState &S, CodePtr OpPC, const Pointer &Ptr,
AccessKinds AK);
/// Checks if a pointer is null.
bool CheckNull(InterpState &S, CodePtr OpPC, const Pointer &Ptr,
CheckSubobjectKind CSK);
/// Checks if a pointer is in range.
bool CheckRange(InterpState &S, CodePtr OpPC, const Pointer &Ptr,
AccessKinds AK);
/// Checks if a field from which a pointer is going to be derived is valid.
bool CheckRange(InterpState &S, CodePtr OpPC, const Pointer &Ptr,
CheckSubobjectKind CSK);
/// Checks if Ptr is a one-past-the-end pointer.
bool CheckSubobject(InterpState &S, CodePtr OpPC, const Pointer &Ptr,
CheckSubobjectKind CSK);
/// Checks if the dowcast using the given offset is possible with the given
/// pointer.
bool CheckDowncast(InterpState &S, CodePtr OpPC, const Pointer &Ptr,
uint32_t Offset);
/// Checks if a pointer points to const storage.
bool CheckConst(InterpState &S, CodePtr OpPC, const Pointer &Ptr);
/// Checks if the Descriptor is of a constexpr or const global variable.
bool CheckConstant(InterpState &S, CodePtr OpPC, const Descriptor *Desc);
/// Checks if a pointer points to a mutable field.
bool CheckMutable(InterpState &S, CodePtr OpPC, const Pointer &Ptr);
/// Checks if a value can be loaded from a block.
bool CheckLoad(InterpState &S, CodePtr OpPC, const Pointer &Ptr,
AccessKinds AK = AK_Read);
bool CheckFinalLoad(InterpState &S, CodePtr OpPC, const Pointer &Ptr);
bool CheckInitialized(InterpState &S, CodePtr OpPC, const Pointer &Ptr,
AccessKinds AK);
/// Check if a global variable is initialized.
bool CheckGlobalInitialized(InterpState &S, CodePtr OpPC, const Pointer &Ptr);
/// Checks if a value can be stored in a block.
bool CheckStore(InterpState &S, CodePtr OpPC, const Pointer &Ptr);
/// Checks if a method can be invoked on an object.
bool CheckInvoke(InterpState &S, CodePtr OpPC, const Pointer &Ptr);
/// Checks if a value can be initialized.
bool CheckInit(InterpState &S, CodePtr OpPC, const Pointer &Ptr);
/// Checks if a method can be called.
bool CheckCallable(InterpState &S, CodePtr OpPC, const Function *F);
/// Checks if calling the currently active function would exceed
/// the allowed call depth.
bool CheckCallDepth(InterpState &S, CodePtr OpPC);
/// Checks the 'this' pointer.
bool CheckThis(InterpState &S, CodePtr OpPC, const Pointer &This);
/// Checks if a method is pure virtual.
bool CheckPure(InterpState &S, CodePtr OpPC, const CXXMethodDecl *MD);
/// Checks if all the arguments annotated as 'nonnull' are in fact not null.
bool CheckNonNullArgs(InterpState &S, CodePtr OpPC, const Function *F,
const CallExpr *CE, unsigned ArgSize);
/// Checks if dynamic memory allocation is available in the current
/// language mode.
bool CheckDynamicMemoryAllocation(InterpState &S, CodePtr OpPC);
/// Diagnose mismatched new[]/delete or new/delete[] pairs.
bool CheckNewDeleteForms(InterpState &S, CodePtr OpPC, bool NewWasArray,
bool DeleteIsArray, const Descriptor *D,
const Expr *NewExpr);
/// Check the source of the pointer passed to delete/delete[] has actually
/// been heap allocated by us.
bool CheckDeleteSource(InterpState &S, CodePtr OpPC, const Expr *Source,
const Pointer &Ptr);
/// Sets the given integral value to the pointer, which is of
/// a std::{weak,partial,strong}_ordering type.
bool SetThreeWayComparisonField(InterpState &S, CodePtr OpPC,
const Pointer &Ptr, const APSInt &IntValue);
/// Copy the contents of Src into Dest.
bool DoMemcpy(InterpState &S, CodePtr OpPC, const Pointer &Src, Pointer &Dest);
/// Checks if the shift operation is legal.
template <typename LT, typename RT>
bool CheckShift(InterpState &S, CodePtr OpPC, const LT &LHS, const RT &RHS,
unsigned Bits) {
if (RHS.isNegative()) {
const SourceInfo &Loc = S.Current->getSource(OpPC);
S.CCEDiag(Loc, diag::note_constexpr_negative_shift) << RHS.toAPSInt();
if (!S.noteUndefinedBehavior())
return false;
}
// C++11 [expr.shift]p1: Shift width must be less than the bit width of
// the shifted type.
if (Bits > 1 && RHS >= RT::from(Bits, RHS.bitWidth())) {
const Expr *E = S.Current->getExpr(OpPC);
const APSInt Val = RHS.toAPSInt();
QualType Ty = E->getType();
S.CCEDiag(E, diag::note_constexpr_large_shift) << Val << Ty << Bits;
if (!S.noteUndefinedBehavior())
return false;
}
if (LHS.isSigned() && !S.getLangOpts().CPlusPlus20) {
const Expr *E = S.Current->getExpr(OpPC);
// C++11 [expr.shift]p2: A signed left shift must have a non-negative
// operand, and must not overflow the corresponding unsigned type.
if (LHS.isNegative()) {
S.CCEDiag(E, diag::note_constexpr_lshift_of_negative) << LHS.toAPSInt();
if (!S.noteUndefinedBehavior())
return false;
} else if (LHS.toUnsigned().countLeadingZeros() <
static_cast<unsigned>(RHS)) {
S.CCEDiag(E, diag::note_constexpr_lshift_discards);
if (!S.noteUndefinedBehavior())
return false;
}
}
// C++2a [expr.shift]p2: [P0907R4]:
// E1 << E2 is the unique value congruent to
// E1 x 2^E2 module 2^N.
return true;
}
/// Checks if Div/Rem operation on LHS and RHS is valid.
template <typename T>
bool CheckDivRem(InterpState &S, CodePtr OpPC, const T &LHS, const T &RHS) {
if (RHS.isZero()) {
const auto *Op = cast<BinaryOperator>(S.Current->getExpr(OpPC));
if constexpr (std::is_same_v<T, Floating>) {
S.CCEDiag(Op, diag::note_expr_divide_by_zero)
<< Op->getRHS()->getSourceRange();
return true;
}
S.FFDiag(Op, diag::note_expr_divide_by_zero)
<< Op->getRHS()->getSourceRange();
return false;
}
if (LHS.isSigned() && LHS.isMin() && RHS.isNegative() && RHS.isMinusOne()) {
APSInt LHSInt = LHS.toAPSInt();
SmallString<32> Trunc;
(-LHSInt.extend(LHSInt.getBitWidth() + 1)).toString(Trunc, 10);
const SourceInfo &Loc = S.Current->getSource(OpPC);
const Expr *E = S.Current->getExpr(OpPC);
S.CCEDiag(Loc, diag::note_constexpr_overflow) << Trunc << E->getType();
return false;
}
return true;
}
template <typename SizeT>
bool CheckArraySize(InterpState &S, CodePtr OpPC, SizeT *NumElements,
unsigned ElemSize, bool IsNoThrow) {
// FIXME: Both the SizeT::from() as well as the
// NumElements.toAPSInt() in this function are rather expensive.
// FIXME: GH63562
// APValue stores array extents as unsigned,
// so anything that is greater that unsigned would overflow when
// constructing the array, we catch this here.
SizeT MaxElements = SizeT::from(Descriptor::MaxArrayElemBytes / ElemSize);
if (NumElements->toAPSInt().getActiveBits() >
ConstantArrayType::getMaxSizeBits(S.getCtx()) ||
*NumElements > MaxElements) {
if (!IsNoThrow) {
const SourceInfo &Loc = S.Current->getSource(OpPC);
S.FFDiag(Loc, diag::note_constexpr_new_too_large)
<< NumElements->toDiagnosticString(S.getCtx());
}
return false;
}
return true;
}
/// Checks if the result of a floating-point operation is valid
/// in the current context.
bool CheckFloatResult(InterpState &S, CodePtr OpPC, const Floating &Result,
APFloat::opStatus Status);
/// Checks why the given DeclRefExpr is invalid.
bool CheckDeclRef(InterpState &S, CodePtr OpPC, const DeclRefExpr *DR);
/// Interpreter entry point.
bool Interpret(InterpState &S, APValue &Result);
/// Interpret a builtin function.
bool InterpretBuiltin(InterpState &S, CodePtr OpPC, const Function *F,
const CallExpr *Call);
/// Interpret an offsetof operation.
bool InterpretOffsetOf(InterpState &S, CodePtr OpPC, const OffsetOfExpr *E,
llvm::ArrayRef<int64_t> ArrayIndices, int64_t &Result);
inline bool Invalid(InterpState &S, CodePtr OpPC);
enum class ArithOp { Add, Sub };
//===----------------------------------------------------------------------===//
// Returning values
//===----------------------------------------------------------------------===//
void cleanupAfterFunctionCall(InterpState &S, CodePtr OpPC);
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool Ret(InterpState &S, CodePtr &PC, APValue &Result) {
const T &Ret = S.Stk.pop<T>();
// Make sure returned pointers are live. We might be trying to return a
// pointer or reference to a local variable.
// Just return false, since a diagnostic has already been emitted in Sema.
if constexpr (std::is_same_v<T, Pointer>) {
// FIXME: We could be calling isLive() here, but the emitted diagnostics
// seem a little weird, at least if the returned expression is of
// pointer type.
// Null pointers are considered live here.
if (!Ret.isZero() && !Ret.isLive())
return false;
}
assert(S.Current);
assert(S.Current->getFrameOffset() == S.Stk.size() && "Invalid frame");
if (!S.checkingPotentialConstantExpression() || S.Current->Caller)
cleanupAfterFunctionCall(S, PC);
if (InterpFrame *Caller = S.Current->Caller) {
PC = S.Current->getRetPC();
delete S.Current;
S.Current = Caller;
S.Stk.push<T>(Ret);
} else {
delete S.Current;
S.Current = nullptr;
if (!ReturnValue<T>(S, Ret, Result))
return false;
}
return true;
}
inline bool RetVoid(InterpState &S, CodePtr &PC, APValue &Result) {
assert(S.Current->getFrameOffset() == S.Stk.size() && "Invalid frame");
if (!S.checkingPotentialConstantExpression() || S.Current->Caller)
cleanupAfterFunctionCall(S, PC);
if (InterpFrame *Caller = S.Current->Caller) {
PC = S.Current->getRetPC();
delete S.Current;
S.Current = Caller;
} else {
delete S.Current;
S.Current = nullptr;
}
return true;
}
//===----------------------------------------------------------------------===//
// Add, Sub, Mul
//===----------------------------------------------------------------------===//
template <typename T, bool (*OpFW)(T, T, unsigned, T *),
template <typename U> class OpAP>
bool AddSubMulHelper(InterpState &S, CodePtr OpPC, unsigned Bits, const T &LHS,
const T &RHS) {
// Fast path - add the numbers with fixed width.
T Result;
if (!OpFW(LHS, RHS, Bits, &Result)) {
S.Stk.push<T>(Result);
return true;
}
// If for some reason evaluation continues, use the truncated results.
S.Stk.push<T>(Result);
// Slow path - compute the result using another bit of precision.
APSInt Value = OpAP<APSInt>()(LHS.toAPSInt(Bits), RHS.toAPSInt(Bits));
// Report undefined behaviour, stopping if required.
const Expr *E = S.Current->getExpr(OpPC);
QualType Type = E->getType();
if (S.checkingForUndefinedBehavior()) {
SmallString<32> Trunc;
Value.trunc(Result.bitWidth())
.toString(Trunc, 10, Result.isSigned(), /*formatAsCLiteral=*/false,
/*UpperCase=*/true, /*InsertSeparators=*/true);
auto Loc = E->getExprLoc();
S.report(Loc, diag::warn_integer_constant_overflow)
<< Trunc << Type << E->getSourceRange();
}
S.CCEDiag(E, diag::note_constexpr_overflow) << Value << Type;
if (!S.noteUndefinedBehavior()) {
S.Stk.pop<T>();
return false;
}
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool Add(InterpState &S, CodePtr OpPC) {
const T &RHS = S.Stk.pop<T>();
const T &LHS = S.Stk.pop<T>();
const unsigned Bits = RHS.bitWidth() + 1;
return AddSubMulHelper<T, T::add, std::plus>(S, OpPC, Bits, LHS, RHS);
}
inline bool Addf(InterpState &S, CodePtr OpPC, llvm::RoundingMode RM) {
const Floating &RHS = S.Stk.pop<Floating>();
const Floating &LHS = S.Stk.pop<Floating>();
Floating Result;
auto Status = Floating::add(LHS, RHS, RM, &Result);
S.Stk.push<Floating>(Result);
return CheckFloatResult(S, OpPC, Result, Status);
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool Sub(InterpState &S, CodePtr OpPC) {
const T &RHS = S.Stk.pop<T>();
const T &LHS = S.Stk.pop<T>();
const unsigned Bits = RHS.bitWidth() + 1;
return AddSubMulHelper<T, T::sub, std::minus>(S, OpPC, Bits, LHS, RHS);
}
inline bool Subf(InterpState &S, CodePtr OpPC, llvm::RoundingMode RM) {
const Floating &RHS = S.Stk.pop<Floating>();
const Floating &LHS = S.Stk.pop<Floating>();
Floating Result;
auto Status = Floating::sub(LHS, RHS, RM, &Result);
S.Stk.push<Floating>(Result);
return CheckFloatResult(S, OpPC, Result, Status);
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool Mul(InterpState &S, CodePtr OpPC) {
const T &RHS = S.Stk.pop<T>();
const T &LHS = S.Stk.pop<T>();
const unsigned Bits = RHS.bitWidth() * 2;
return AddSubMulHelper<T, T::mul, std::multiplies>(S, OpPC, Bits, LHS, RHS);
}
inline bool Mulf(InterpState &S, CodePtr OpPC, llvm::RoundingMode RM) {
const Floating &RHS = S.Stk.pop<Floating>();
const Floating &LHS = S.Stk.pop<Floating>();
Floating Result;
auto Status = Floating::mul(LHS, RHS, RM, &Result);
S.Stk.push<Floating>(Result);
return CheckFloatResult(S, OpPC, Result, Status);
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
inline bool Mulc(InterpState &S, CodePtr OpPC) {
const Pointer &RHS = S.Stk.pop<Pointer>();
const Pointer &LHS = S.Stk.pop<Pointer>();
const Pointer &Result = S.Stk.peek<Pointer>();
if constexpr (std::is_same_v<T, Floating>) {
APFloat A = LHS.atIndex(0).deref<Floating>().getAPFloat();
APFloat B = LHS.atIndex(1).deref<Floating>().getAPFloat();
APFloat C = RHS.atIndex(0).deref<Floating>().getAPFloat();
APFloat D = RHS.atIndex(1).deref<Floating>().getAPFloat();
APFloat ResR(A.getSemantics());
APFloat ResI(A.getSemantics());
HandleComplexComplexMul(A, B, C, D, ResR, ResI);
// Copy into the result.
Result.atIndex(0).deref<Floating>() = Floating(ResR);
Result.atIndex(0).initialize();
Result.atIndex(1).deref<Floating>() = Floating(ResI);
Result.atIndex(1).initialize();
Result.initialize();
} else {
// Integer element type.
const T &LHSR = LHS.atIndex(0).deref<T>();
const T &LHSI = LHS.atIndex(1).deref<T>();
const T &RHSR = RHS.atIndex(0).deref<T>();
const T &RHSI = RHS.atIndex(1).deref<T>();
unsigned Bits = LHSR.bitWidth();
// real(Result) = (real(LHS) * real(RHS)) - (imag(LHS) * imag(RHS))
T A;
if (T::mul(LHSR, RHSR, Bits, &A))
return false;
T B;
if (T::mul(LHSI, RHSI, Bits, &B))
return false;
if (T::sub(A, B, Bits, &Result.atIndex(0).deref<T>()))
return false;
Result.atIndex(0).initialize();
// imag(Result) = (real(LHS) * imag(RHS)) + (imag(LHS) * real(RHS))
if (T::mul(LHSR, RHSI, Bits, &A))
return false;
if (T::mul(LHSI, RHSR, Bits, &B))
return false;
if (T::add(A, B, Bits, &Result.atIndex(1).deref<T>()))
return false;
Result.atIndex(1).initialize();
Result.initialize();
}
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
inline bool Divc(InterpState &S, CodePtr OpPC) {
const Pointer &RHS = S.Stk.pop<Pointer>();
const Pointer &LHS = S.Stk.pop<Pointer>();
const Pointer &Result = S.Stk.peek<Pointer>();
if constexpr (std::is_same_v<T, Floating>) {
APFloat A = LHS.atIndex(0).deref<Floating>().getAPFloat();
APFloat B = LHS.atIndex(1).deref<Floating>().getAPFloat();
APFloat C = RHS.atIndex(0).deref<Floating>().getAPFloat();
APFloat D = RHS.atIndex(1).deref<Floating>().getAPFloat();
APFloat ResR(A.getSemantics());
APFloat ResI(A.getSemantics());
HandleComplexComplexDiv(A, B, C, D, ResR, ResI);
// Copy into the result.
Result.atIndex(0).deref<Floating>() = Floating(ResR);
Result.atIndex(0).initialize();
Result.atIndex(1).deref<Floating>() = Floating(ResI);
Result.atIndex(1).initialize();
Result.initialize();
} else {
// Integer element type.
const T &LHSR = LHS.atIndex(0).deref<T>();
const T &LHSI = LHS.atIndex(1).deref<T>();
const T &RHSR = RHS.atIndex(0).deref<T>();
const T &RHSI = RHS.atIndex(1).deref<T>();
unsigned Bits = LHSR.bitWidth();
const T Zero = T::from(0, Bits);
if (Compare(RHSR, Zero) == ComparisonCategoryResult::Equal &&
Compare(RHSI, Zero) == ComparisonCategoryResult::Equal) {
const SourceInfo &E = S.Current->getSource(OpPC);
S.FFDiag(E, diag::note_expr_divide_by_zero);
return false;
}
// Den = real(RHS)² + imag(RHS)²
T A, B;
if (T::mul(RHSR, RHSR, Bits, &A) || T::mul(RHSI, RHSI, Bits, &B))
return false;
T Den;
if (T::add(A, B, Bits, &Den))
return false;
// real(Result) = ((real(LHS) * real(RHS)) + (imag(LHS) * imag(RHS))) / Den
T &ResultR = Result.atIndex(0).deref<T>();
T &ResultI = Result.atIndex(1).deref<T>();
if (T::mul(LHSR, RHSR, Bits, &A) || T::mul(LHSI, RHSI, Bits, &B))
return false;
if (T::add(A, B, Bits, &ResultR))
return false;
if (T::div(ResultR, Den, Bits, &ResultR))
return false;
Result.atIndex(0).initialize();
// imag(Result) = ((imag(LHS) * real(RHS)) - (real(LHS) * imag(RHS))) / Den
if (T::mul(LHSI, RHSR, Bits, &A) || T::mul(LHSR, RHSI, Bits, &B))
return false;
if (T::sub(A, B, Bits, &ResultI))
return false;
if (T::div(ResultI, Den, Bits, &ResultI))
return false;
Result.atIndex(1).initialize();
Result.initialize();
}
return true;
}
/// 1) Pops the RHS from the stack.
/// 2) Pops the LHS from the stack.
/// 3) Pushes 'LHS & RHS' on the stack
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool BitAnd(InterpState &S, CodePtr OpPC) {
const T &RHS = S.Stk.pop<T>();
const T &LHS = S.Stk.pop<T>();
unsigned Bits = RHS.bitWidth();
T Result;
if (!T::bitAnd(LHS, RHS, Bits, &Result)) {
S.Stk.push<T>(Result);
return true;
}
return false;
}
/// 1) Pops the RHS from the stack.
/// 2) Pops the LHS from the stack.
/// 3) Pushes 'LHS | RHS' on the stack
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool BitOr(InterpState &S, CodePtr OpPC) {
const T &RHS = S.Stk.pop<T>();
const T &LHS = S.Stk.pop<T>();
unsigned Bits = RHS.bitWidth();
T Result;
if (!T::bitOr(LHS, RHS, Bits, &Result)) {
S.Stk.push<T>(Result);
return true;
}
return false;
}
/// 1) Pops the RHS from the stack.
/// 2) Pops the LHS from the stack.
/// 3) Pushes 'LHS ^ RHS' on the stack
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool BitXor(InterpState &S, CodePtr OpPC) {
const T &RHS = S.Stk.pop<T>();
const T &LHS = S.Stk.pop<T>();
unsigned Bits = RHS.bitWidth();
T Result;
if (!T::bitXor(LHS, RHS, Bits, &Result)) {
S.Stk.push<T>(Result);
return true;
}
return false;
}
/// 1) Pops the RHS from the stack.
/// 2) Pops the LHS from the stack.
/// 3) Pushes 'LHS % RHS' on the stack (the remainder of dividing LHS by RHS).
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool Rem(InterpState &S, CodePtr OpPC) {
const T &RHS = S.Stk.pop<T>();
const T &LHS = S.Stk.pop<T>();
if (!CheckDivRem(S, OpPC, LHS, RHS))
return false;
const unsigned Bits = RHS.bitWidth() * 2;
T Result;
if (!T::rem(LHS, RHS, Bits, &Result)) {
S.Stk.push<T>(Result);
return true;
}
return false;
}
/// 1) Pops the RHS from the stack.
/// 2) Pops the LHS from the stack.
/// 3) Pushes 'LHS / RHS' on the stack
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool Div(InterpState &S, CodePtr OpPC) {
const T &RHS = S.Stk.pop<T>();
const T &LHS = S.Stk.pop<T>();
if (!CheckDivRem(S, OpPC, LHS, RHS))
return false;
const unsigned Bits = RHS.bitWidth() * 2;
T Result;
if (!T::div(LHS, RHS, Bits, &Result)) {
S.Stk.push<T>(Result);
return true;
}
return false;
}
inline bool Divf(InterpState &S, CodePtr OpPC, llvm::RoundingMode RM) {
const Floating &RHS = S.Stk.pop<Floating>();
const Floating &LHS = S.Stk.pop<Floating>();
if (!CheckDivRem(S, OpPC, LHS, RHS))
return false;
Floating Result;
auto Status = Floating::div(LHS, RHS, RM, &Result);
S.Stk.push<Floating>(Result);
return CheckFloatResult(S, OpPC, Result, Status);
}
//===----------------------------------------------------------------------===//
// Inv
//===----------------------------------------------------------------------===//
inline bool Inv(InterpState &S, CodePtr OpPC) {
const auto &Val = S.Stk.pop<Boolean>();
S.Stk.push<Boolean>(!Val);
return true;
}
//===----------------------------------------------------------------------===//
// Neg
//===----------------------------------------------------------------------===//
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool Neg(InterpState &S, CodePtr OpPC) {
const T &Value = S.Stk.pop<T>();
T Result;
if (!T::neg(Value, &Result)) {
S.Stk.push<T>(Result);
return true;
}
assert(isIntegralType(Name) &&
"don't expect other types to fail at constexpr negation");
S.Stk.push<T>(Result);
APSInt NegatedValue = -Value.toAPSInt(Value.bitWidth() + 1);
const Expr *E = S.Current->getExpr(OpPC);
QualType Type = E->getType();
if (S.checkingForUndefinedBehavior()) {
SmallString<32> Trunc;
NegatedValue.trunc(Result.bitWidth())
.toString(Trunc, 10, Result.isSigned(), /*formatAsCLiteral=*/false,
/*UpperCase=*/true, /*InsertSeparators=*/true);
auto Loc = E->getExprLoc();
S.report(Loc, diag::warn_integer_constant_overflow)
<< Trunc << Type << E->getSourceRange();
return true;
}
S.CCEDiag(E, diag::note_constexpr_overflow) << NegatedValue << Type;
return S.noteUndefinedBehavior();
}
enum class PushVal : bool {
No,
Yes,
};
enum class IncDecOp {
Inc,
Dec,
};
template <typename T, IncDecOp Op, PushVal DoPush>
bool IncDecHelper(InterpState &S, CodePtr OpPC, const Pointer &Ptr) {
assert(!Ptr.isDummy());
if constexpr (std::is_same_v<T, Boolean>) {
if (!S.getLangOpts().CPlusPlus14)
return Invalid(S, OpPC);
}
const T &Value = Ptr.deref<T>();
T Result;
if constexpr (DoPush == PushVal::Yes)
S.Stk.push<T>(Value);
if constexpr (Op == IncDecOp::Inc) {
if (!T::increment(Value, &Result)) {
Ptr.deref<T>() = Result;
return true;
}
} else {
if (!T::decrement(Value, &Result)) {
Ptr.deref<T>() = Result;
return true;
}
}
// Something went wrong with the previous operation. Compute the
// result with another bit of precision.
unsigned Bits = Value.bitWidth() + 1;
APSInt APResult;
if constexpr (Op == IncDecOp::Inc)
APResult = ++Value.toAPSInt(Bits);
else
APResult = --Value.toAPSInt(Bits);
// Report undefined behaviour, stopping if required.
const Expr *E = S.Current->getExpr(OpPC);
QualType Type = E->getType();
if (S.checkingForUndefinedBehavior()) {
SmallString<32> Trunc;
APResult.trunc(Result.bitWidth())
.toString(Trunc, 10, Result.isSigned(), /*formatAsCLiteral=*/false,
/*UpperCase=*/true, /*InsertSeparators=*/true);
auto Loc = E->getExprLoc();
S.report(Loc, diag::warn_integer_constant_overflow)
<< Trunc << Type << E->getSourceRange();
return true;
}
S.CCEDiag(E, diag::note_constexpr_overflow) << APResult << Type;
return S.noteUndefinedBehavior();
}
/// 1) Pops a pointer from the stack
/// 2) Load the value from the pointer
/// 3) Writes the value increased by one back to the pointer
/// 4) Pushes the original (pre-inc) value on the stack.
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool Inc(InterpState &S, CodePtr OpPC) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckLoad(S, OpPC, Ptr, AK_Increment))
return false;
return IncDecHelper<T, IncDecOp::Inc, PushVal::Yes>(S, OpPC, Ptr);
}
/// 1) Pops a pointer from the stack
/// 2) Load the value from the pointer
/// 3) Writes the value increased by one back to the pointer
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool IncPop(InterpState &S, CodePtr OpPC) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckLoad(S, OpPC, Ptr, AK_Increment))
return false;
return IncDecHelper<T, IncDecOp::Inc, PushVal::No>(S, OpPC, Ptr);
}
/// 1) Pops a pointer from the stack
/// 2) Load the value from the pointer
/// 3) Writes the value decreased by one back to the pointer
/// 4) Pushes the original (pre-dec) value on the stack.
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool Dec(InterpState &S, CodePtr OpPC) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckLoad(S, OpPC, Ptr, AK_Decrement))
return false;
return IncDecHelper<T, IncDecOp::Dec, PushVal::Yes>(S, OpPC, Ptr);
}
/// 1) Pops a pointer from the stack
/// 2) Load the value from the pointer
/// 3) Writes the value decreased by one back to the pointer
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool DecPop(InterpState &S, CodePtr OpPC) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckLoad(S, OpPC, Ptr, AK_Decrement))
return false;
return IncDecHelper<T, IncDecOp::Dec, PushVal::No>(S, OpPC, Ptr);
}
template <IncDecOp Op, PushVal DoPush>
bool IncDecFloatHelper(InterpState &S, CodePtr OpPC, const Pointer &Ptr,
llvm::RoundingMode RM) {
Floating Value = Ptr.deref<Floating>();
Floating Result;
if constexpr (DoPush == PushVal::Yes)
S.Stk.push<Floating>(Value);
llvm::APFloat::opStatus Status;
if constexpr (Op == IncDecOp::Inc)
Status = Floating::increment(Value, RM, &Result);
else
Status = Floating::decrement(Value, RM, &Result);
Ptr.deref<Floating>() = Result;
return CheckFloatResult(S, OpPC, Result, Status);
}
inline bool Incf(InterpState &S, CodePtr OpPC, llvm::RoundingMode RM) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckLoad(S, OpPC, Ptr, AK_Increment))
return false;
return IncDecFloatHelper<IncDecOp::Inc, PushVal::Yes>(S, OpPC, Ptr, RM);
}
inline bool IncfPop(InterpState &S, CodePtr OpPC, llvm::RoundingMode RM) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckLoad(S, OpPC, Ptr, AK_Increment))
return false;
return IncDecFloatHelper<IncDecOp::Inc, PushVal::No>(S, OpPC, Ptr, RM);
}
inline bool Decf(InterpState &S, CodePtr OpPC, llvm::RoundingMode RM) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckLoad(S, OpPC, Ptr, AK_Decrement))
return false;
return IncDecFloatHelper<IncDecOp::Dec, PushVal::Yes>(S, OpPC, Ptr, RM);
}
inline bool DecfPop(InterpState &S, CodePtr OpPC, llvm::RoundingMode RM) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckLoad(S, OpPC, Ptr, AK_Decrement))
return false;
return IncDecFloatHelper<IncDecOp::Dec, PushVal::No>(S, OpPC, Ptr, RM);
}
/// 1) Pops the value from the stack.
/// 2) Pushes the bitwise complemented value on the stack (~V).
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool Comp(InterpState &S, CodePtr OpPC) {
const T &Val = S.Stk.pop<T>();
T Result;
if (!T::comp(Val, &Result)) {
S.Stk.push<T>(Result);
return true;
}
return false;
}
//===----------------------------------------------------------------------===//
// EQ, NE, GT, GE, LT, LE
//===----------------------------------------------------------------------===//
using CompareFn = llvm::function_ref<bool(ComparisonCategoryResult)>;
template <typename T>
bool CmpHelper(InterpState &S, CodePtr OpPC, CompareFn Fn) {
assert((!std::is_same_v<T, MemberPointer>) &&
"Non-equality comparisons on member pointer types should already be "
"rejected in Sema.");
using BoolT = PrimConv<PT_Bool>::T;
const T &RHS = S.Stk.pop<T>();
const T &LHS = S.Stk.pop<T>();
S.Stk.push<BoolT>(BoolT::from(Fn(LHS.compare(RHS))));
return true;
}
template <typename T>
bool CmpHelperEQ(InterpState &S, CodePtr OpPC, CompareFn Fn) {
return CmpHelper<T>(S, OpPC, Fn);
}
/// Function pointers cannot be compared in an ordered way.
template <>
inline bool CmpHelper<FunctionPointer>(InterpState &S, CodePtr OpPC,
CompareFn Fn) {
const auto &RHS = S.Stk.pop<FunctionPointer>();
const auto &LHS = S.Stk.pop<FunctionPointer>();
const SourceInfo &Loc = S.Current->getSource(OpPC);
S.FFDiag(Loc, diag::note_constexpr_pointer_comparison_unspecified)
<< LHS.toDiagnosticString(S.getCtx())
<< RHS.toDiagnosticString(S.getCtx());
return false;
}
template <>
inline bool CmpHelperEQ<FunctionPointer>(InterpState &S, CodePtr OpPC,
CompareFn Fn) {
const auto &RHS = S.Stk.pop<FunctionPointer>();
const auto &LHS = S.Stk.pop<FunctionPointer>();
// We cannot compare against weak declarations at compile time.
for (const auto &FP : {LHS, RHS}) {
if (FP.isWeak()) {
const SourceInfo &Loc = S.Current->getSource(OpPC);
S.FFDiag(Loc, diag::note_constexpr_pointer_weak_comparison)
<< FP.toDiagnosticString(S.getCtx());
return false;
}
}
S.Stk.push<Boolean>(Boolean::from(Fn(LHS.compare(RHS))));
return true;
}
template <>
inline bool CmpHelper<Pointer>(InterpState &S, CodePtr OpPC, CompareFn Fn) {
using BoolT = PrimConv<PT_Bool>::T;
const Pointer &RHS = S.Stk.pop<Pointer>();
const Pointer &LHS = S.Stk.pop<Pointer>();
if (!Pointer::hasSameBase(LHS, RHS)) {
const SourceInfo &Loc = S.Current->getSource(OpPC);
S.FFDiag(Loc, diag::note_constexpr_pointer_comparison_unspecified)
<< LHS.toDiagnosticString(S.getCtx())
<< RHS.toDiagnosticString(S.getCtx());
return false;
} else {
unsigned VL = LHS.getByteOffset();
unsigned VR = RHS.getByteOffset();
S.Stk.push<BoolT>(BoolT::from(Fn(Compare(VL, VR))));
return true;
}
}
template <>
inline bool CmpHelperEQ<Pointer>(InterpState &S, CodePtr OpPC, CompareFn Fn) {
using BoolT = PrimConv<PT_Bool>::T;
const Pointer &RHS = S.Stk.pop<Pointer>();
const Pointer &LHS = S.Stk.pop<Pointer>();
if (LHS.isZero() && RHS.isZero()) {
S.Stk.push<BoolT>(BoolT::from(Fn(ComparisonCategoryResult::Equal)));
return true;
}
// Reject comparisons to weak pointers.
for (const auto &P : {LHS, RHS}) {
if (P.isZero())
continue;
if (P.isWeak()) {
const SourceInfo &Loc = S.Current->getSource(OpPC);
S.FFDiag(Loc, diag::note_constexpr_pointer_weak_comparison)
<< P.toDiagnosticString(S.getCtx());
return false;
}
}
if (!Pointer::hasSameBase(LHS, RHS)) {
if (LHS.isOnePastEnd() && !RHS.isOnePastEnd() && !RHS.isZero() &&
RHS.getOffset() == 0) {
const SourceInfo &Loc = S.Current->getSource(OpPC);
S.FFDiag(Loc, diag::note_constexpr_pointer_comparison_past_end)
<< LHS.toDiagnosticString(S.getCtx());
return false;
} else if (RHS.isOnePastEnd() && !LHS.isOnePastEnd() && !LHS.isZero() &&
LHS.getOffset() == 0) {
const SourceInfo &Loc = S.Current->getSource(OpPC);
S.FFDiag(Loc, diag::note_constexpr_pointer_comparison_past_end)
<< RHS.toDiagnosticString(S.getCtx());
return false;
}
S.Stk.push<BoolT>(BoolT::from(Fn(ComparisonCategoryResult::Unordered)));
return true;
} else {
unsigned VL = LHS.getByteOffset();
unsigned VR = RHS.getByteOffset();
// In our Pointer class, a pointer to an array and a pointer to the first
// element in the same array are NOT equal. They have the same Base value,
// but a different Offset. This is a pretty rare case, so we fix this here
// by comparing pointers to the first elements.
if (!LHS.isZero() && LHS.isArrayRoot())
VL = LHS.atIndex(0).getByteOffset();
if (!RHS.isZero() && RHS.isArrayRoot())
VR = RHS.atIndex(0).getByteOffset();
S.Stk.push<BoolT>(BoolT::from(Fn(Compare(VL, VR))));
return true;
}
}
template <>
inline bool CmpHelperEQ<MemberPointer>(InterpState &S, CodePtr OpPC,
CompareFn Fn) {
const auto &RHS = S.Stk.pop<MemberPointer>();
const auto &LHS = S.Stk.pop<MemberPointer>();
// If either operand is a pointer to a weak function, the comparison is not
// constant.
for (const auto &MP : {LHS, RHS}) {
if (const CXXMethodDecl *MD = MP.getMemberFunction(); MD && MD->isWeak()) {
const SourceInfo &Loc = S.Current->getSource(OpPC);
S.FFDiag(Loc, diag::note_constexpr_mem_pointer_weak_comparison) << MD;
return false;
}
}
// C++11 [expr.eq]p2:
// If both operands are null, they compare equal. Otherwise if only one is
// null, they compare unequal.
if (LHS.isZero() && RHS.isZero()) {
S.Stk.push<Boolean>(Fn(ComparisonCategoryResult::Equal));
return true;
}
if (LHS.isZero() || RHS.isZero()) {
S.Stk.push<Boolean>(Fn(ComparisonCategoryResult::Unordered));
return true;
}
// We cannot compare against virtual declarations at compile time.
for (const auto &MP : {LHS, RHS}) {
if (const CXXMethodDecl *MD = MP.getMemberFunction();
MD && MD->isVirtual()) {
const SourceInfo &Loc = S.Current->getSource(OpPC);
S.CCEDiag(Loc, diag::note_constexpr_compare_virtual_mem_ptr) << MD;
}
}
S.Stk.push<Boolean>(Boolean::from(Fn(LHS.compare(RHS))));
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool EQ(InterpState &S, CodePtr OpPC) {
return CmpHelperEQ<T>(S, OpPC, [](ComparisonCategoryResult R) {
return R == ComparisonCategoryResult::Equal;
});
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool CMP3(InterpState &S, CodePtr OpPC, const ComparisonCategoryInfo *CmpInfo) {
const T &RHS = S.Stk.pop<T>();
const T &LHS = S.Stk.pop<T>();
const Pointer &P = S.Stk.peek<Pointer>();
ComparisonCategoryResult CmpResult = LHS.compare(RHS);
if (CmpResult == ComparisonCategoryResult::Unordered) {
// This should only happen with pointers.
const SourceInfo &Loc = S.Current->getSource(OpPC);
S.FFDiag(Loc, diag::note_constexpr_pointer_comparison_unspecified)
<< LHS.toDiagnosticString(S.getCtx())
<< RHS.toDiagnosticString(S.getCtx());
return false;
}
assert(CmpInfo);
const auto *CmpValueInfo =
CmpInfo->getValueInfo(CmpInfo->makeWeakResult(CmpResult));
assert(CmpValueInfo);
assert(CmpValueInfo->hasValidIntValue());
return SetThreeWayComparisonField(S, OpPC, P, CmpValueInfo->getIntValue());
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool NE(InterpState &S, CodePtr OpPC) {
return CmpHelperEQ<T>(S, OpPC, [](ComparisonCategoryResult R) {
return R != ComparisonCategoryResult::Equal;
});
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool LT(InterpState &S, CodePtr OpPC) {
return CmpHelper<T>(S, OpPC, [](ComparisonCategoryResult R) {
return R == ComparisonCategoryResult::Less;
});
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool LE(InterpState &S, CodePtr OpPC) {
return CmpHelper<T>(S, OpPC, [](ComparisonCategoryResult R) {
return R == ComparisonCategoryResult::Less ||
R == ComparisonCategoryResult::Equal;
});
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool GT(InterpState &S, CodePtr OpPC) {
return CmpHelper<T>(S, OpPC, [](ComparisonCategoryResult R) {
return R == ComparisonCategoryResult::Greater;
});
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool GE(InterpState &S, CodePtr OpPC) {
return CmpHelper<T>(S, OpPC, [](ComparisonCategoryResult R) {
return R == ComparisonCategoryResult::Greater ||
R == ComparisonCategoryResult::Equal;
});
}
//===----------------------------------------------------------------------===//
// InRange
//===----------------------------------------------------------------------===//
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool InRange(InterpState &S, CodePtr OpPC) {
const T RHS = S.Stk.pop<T>();
const T LHS = S.Stk.pop<T>();
const T Value = S.Stk.pop<T>();
S.Stk.push<bool>(LHS <= Value && Value <= RHS);
return true;
}
//===----------------------------------------------------------------------===//
// Dup, Pop, Test
//===----------------------------------------------------------------------===//
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool Dup(InterpState &S, CodePtr OpPC) {
S.Stk.push<T>(S.Stk.peek<T>());
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool Pop(InterpState &S, CodePtr OpPC) {
S.Stk.pop<T>();
return true;
}
/// [Value1, Value2] -> [Value2, Value1]
template <PrimType TopName, PrimType BottomName>
bool Flip(InterpState &S, CodePtr OpPC) {
using TopT = typename PrimConv<TopName>::T;
using BottomT = typename PrimConv<BottomName>::T;
const auto &Top = S.Stk.pop<TopT>();
const auto &Bottom = S.Stk.pop<BottomT>();
S.Stk.push<TopT>(Top);
S.Stk.push<BottomT>(Bottom);
return true;
}
//===----------------------------------------------------------------------===//
// Const
//===----------------------------------------------------------------------===//
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool Const(InterpState &S, CodePtr OpPC, const T &Arg) {
S.Stk.push<T>(Arg);
return true;
}
//===----------------------------------------------------------------------===//
// Get/Set Local/Param/Global/This
//===----------------------------------------------------------------------===//
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool GetLocal(InterpState &S, CodePtr OpPC, uint32_t I) {
const Pointer &Ptr = S.Current->getLocalPointer(I);
if (!CheckLoad(S, OpPC, Ptr))
return false;
S.Stk.push<T>(Ptr.deref<T>());
return true;
}
/// 1) Pops the value from the stack.
/// 2) Writes the value to the local variable with the
/// given offset.
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool SetLocal(InterpState &S, CodePtr OpPC, uint32_t I) {
S.Current->setLocal<T>(I, S.Stk.pop<T>());
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool GetParam(InterpState &S, CodePtr OpPC, uint32_t I) {
if (S.checkingPotentialConstantExpression()) {
return false;
}
S.Stk.push<T>(S.Current->getParam<T>(I));
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool SetParam(InterpState &S, CodePtr OpPC, uint32_t I) {
S.Current->setParam<T>(I, S.Stk.pop<T>());
return true;
}
/// 1) Peeks a pointer on the stack
/// 2) Pushes the value of the pointer's field on the stack
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool GetField(InterpState &S, CodePtr OpPC, uint32_t I) {
const Pointer &Obj = S.Stk.peek<Pointer>();
if (!CheckNull(S, OpPC, Obj, CSK_Field))
return false;
if (!CheckRange(S, OpPC, Obj, CSK_Field))
return false;
const Pointer &Field = Obj.atField(I);
if (!CheckLoad(S, OpPC, Field))
return false;
S.Stk.push<T>(Field.deref<T>());
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool SetField(InterpState &S, CodePtr OpPC, uint32_t I) {
const T &Value = S.Stk.pop<T>();
const Pointer &Obj = S.Stk.peek<Pointer>();
if (!CheckNull(S, OpPC, Obj, CSK_Field))
return false;
if (!CheckRange(S, OpPC, Obj, CSK_Field))
return false;
const Pointer &Field = Obj.atField(I);
if (!CheckStore(S, OpPC, Field))
return false;
Field.initialize();
Field.deref<T>() = Value;
return true;
}
/// 1) Pops a pointer from the stack
/// 2) Pushes the value of the pointer's field on the stack
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool GetFieldPop(InterpState &S, CodePtr OpPC, uint32_t I) {
const Pointer &Obj = S.Stk.pop<Pointer>();
if (!CheckNull(S, OpPC, Obj, CSK_Field))
return false;
if (!CheckRange(S, OpPC, Obj, CSK_Field))
return false;
const Pointer &Field = Obj.atField(I);
if (!CheckLoad(S, OpPC, Field))
return false;
S.Stk.push<T>(Field.deref<T>());
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool GetThisField(InterpState &S, CodePtr OpPC, uint32_t I) {
if (S.checkingPotentialConstantExpression())
return false;
const Pointer &This = S.Current->getThis();
if (!CheckThis(S, OpPC, This))
return false;
const Pointer &Field = This.atField(I);
if (!CheckLoad(S, OpPC, Field))
return false;
S.Stk.push<T>(Field.deref<T>());
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool SetThisField(InterpState &S, CodePtr OpPC, uint32_t I) {
if (S.checkingPotentialConstantExpression())
return false;
const T &Value = S.Stk.pop<T>();
const Pointer &This = S.Current->getThis();
if (!CheckThis(S, OpPC, This))
return false;
const Pointer &Field = This.atField(I);
if (!CheckStore(S, OpPC, Field))
return false;
Field.deref<T>() = Value;
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool GetGlobal(InterpState &S, CodePtr OpPC, uint32_t I) {
const Pointer &Ptr = S.P.getPtrGlobal(I);
if (!CheckConstant(S, OpPC, Ptr.getFieldDesc()))
return false;
if (Ptr.isExtern())
return false;
// If a global variable is uninitialized, that means the initializer we've
// compiled for it wasn't a constant expression. Diagnose that.
if (!CheckGlobalInitialized(S, OpPC, Ptr))
return false;
S.Stk.push<T>(Ptr.deref<T>());
return true;
}
/// Same as GetGlobal, but without the checks.
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool GetGlobalUnchecked(InterpState &S, CodePtr OpPC, uint32_t I) {
const Pointer &Ptr = S.P.getPtrGlobal(I);
if (!Ptr.isInitialized())
return false;
S.Stk.push<T>(Ptr.deref<T>());
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool SetGlobal(InterpState &S, CodePtr OpPC, uint32_t I) {
// TODO: emit warning.
return false;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool InitGlobal(InterpState &S, CodePtr OpPC, uint32_t I) {
const Pointer &P = S.P.getGlobal(I);
P.deref<T>() = S.Stk.pop<T>();
P.initialize();
return true;
}
/// 1) Converts the value on top of the stack to an APValue
/// 2) Sets that APValue on \Temp
/// 3) Initializes global with index \I with that
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool InitGlobalTemp(InterpState &S, CodePtr OpPC, uint32_t I,
const LifetimeExtendedTemporaryDecl *Temp) {
const Pointer &Ptr = S.P.getGlobal(I);
const T Value = S.Stk.peek<T>();
APValue APV = Value.toAPValue(S.getCtx());
APValue *Cached = Temp->getOrCreateValue(true);
*Cached = APV;
assert(Ptr.getDeclDesc()->asExpr());
S.SeenGlobalTemporaries.push_back(
std::make_pair(Ptr.getDeclDesc()->asExpr(), Temp));
Ptr.deref<T>() = S.Stk.pop<T>();
Ptr.initialize();
return true;
}
/// 1) Converts the value on top of the stack to an APValue
/// 2) Sets that APValue on \Temp
/// 3) Initialized global with index \I with that
inline bool InitGlobalTempComp(InterpState &S, CodePtr OpPC,
const LifetimeExtendedTemporaryDecl *Temp) {
assert(Temp);
const Pointer &P = S.Stk.peek<Pointer>();
APValue *Cached = Temp->getOrCreateValue(true);
S.SeenGlobalTemporaries.push_back(
std::make_pair(P.getDeclDesc()->asExpr(), Temp));
if (std::optional<APValue> APV =
P.toRValue(S.getCtx(), Temp->getTemporaryExpr()->getType())) {
*Cached = *APV;
return true;
}
return false;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool InitThisField(InterpState &S, CodePtr OpPC, uint32_t I) {
if (S.checkingPotentialConstantExpression())
return false;
const Pointer &This = S.Current->getThis();
if (!CheckThis(S, OpPC, This))
return false;
const Pointer &Field = This.atField(I);
Field.deref<T>() = S.Stk.pop<T>();
Field.activate();
Field.initialize();
return true;
}
// FIXME: The Field pointer here is too much IMO and we could instead just
// pass an Offset + BitWidth pair.
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool InitThisBitField(InterpState &S, CodePtr OpPC, const Record::Field *F,
uint32_t FieldOffset) {
assert(F->isBitField());
if (S.checkingPotentialConstantExpression())
return false;
const Pointer &This = S.Current->getThis();
if (!CheckThis(S, OpPC, This))
return false;
const Pointer &Field = This.atField(FieldOffset);
const auto &Value = S.Stk.pop<T>();
Field.deref<T>() = Value.truncate(F->Decl->getBitWidthValue(S.getCtx()));
Field.initialize();
return true;
}
/// 1) Pops the value from the stack
/// 2) Peeks a pointer from the stack
/// 3) Pushes the value to field I of the pointer on the stack
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool InitField(InterpState &S, CodePtr OpPC, uint32_t I) {
const T &Value = S.Stk.pop<T>();
const Pointer &Field = S.Stk.peek<Pointer>().atField(I);
Field.deref<T>() = Value;
Field.activate();
Field.initialize();
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool InitBitField(InterpState &S, CodePtr OpPC, const Record::Field *F) {
assert(F->isBitField());
const T &Value = S.Stk.pop<T>();
const Pointer &Field = S.Stk.peek<Pointer>().atField(F->Offset);
Field.deref<T>() = Value.truncate(F->Decl->getBitWidthValue(S.getCtx()));
Field.activate();
Field.initialize();
return true;
}
//===----------------------------------------------------------------------===//
// GetPtr Local/Param/Global/Field/This
//===----------------------------------------------------------------------===//
inline bool GetPtrLocal(InterpState &S, CodePtr OpPC, uint32_t I) {
S.Stk.push<Pointer>(S.Current->getLocalPointer(I));
return true;
}
inline bool GetPtrParam(InterpState &S, CodePtr OpPC, uint32_t I) {
if (S.checkingPotentialConstantExpression()) {
return false;
}
S.Stk.push<Pointer>(S.Current->getParamPointer(I));
return true;
}
inline bool GetPtrGlobal(InterpState &S, CodePtr OpPC, uint32_t I) {
S.Stk.push<Pointer>(S.P.getPtrGlobal(I));
return true;
}
/// 1) Peeks a Pointer
/// 2) Pushes Pointer.atField(Off) on the stack
inline bool GetPtrField(InterpState &S, CodePtr OpPC, uint32_t Off) {
const Pointer &Ptr = S.Stk.peek<Pointer>();
if (S.getLangOpts().CPlusPlus && S.inConstantContext() &&
!CheckNull(S, OpPC, Ptr, CSK_Field))
return false;
if (!CheckExtern(S, OpPC, Ptr))
return false;
if (!CheckRange(S, OpPC, Ptr, CSK_Field))
return false;
if (!CheckArray(S, OpPC, Ptr))
return false;
if (!CheckSubobject(S, OpPC, Ptr, CSK_Field))
return false;
if (Ptr.isBlockPointer() && Off > Ptr.block()->getSize())
return false;
if (Ptr.isIntegralPointer()) {
S.Stk.push<Pointer>(Ptr.asIntPointer().atOffset(S.getCtx(), Off));
return true;
}
S.Stk.push<Pointer>(Ptr.atField(Off));
return true;
}
inline bool GetPtrFieldPop(InterpState &S, CodePtr OpPC, uint32_t Off) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (S.getLangOpts().CPlusPlus && S.inConstantContext() &&
!CheckNull(S, OpPC, Ptr, CSK_Field))
return false;
if (!CheckExtern(S, OpPC, Ptr))
return false;
if (!CheckRange(S, OpPC, Ptr, CSK_Field))
return false;
if (!CheckArray(S, OpPC, Ptr))
return false;
if (!CheckSubobject(S, OpPC, Ptr, CSK_Field))
return false;
if (Ptr.isBlockPointer() && Off > Ptr.block()->getSize())
return false;
if (Ptr.isIntegralPointer()) {
S.Stk.push<Pointer>(Ptr.asIntPointer().atOffset(S.getCtx(), Off));
return true;
}
S.Stk.push<Pointer>(Ptr.atField(Off));
return true;
}
inline bool GetPtrThisField(InterpState &S, CodePtr OpPC, uint32_t Off) {
if (S.checkingPotentialConstantExpression())
return false;
const Pointer &This = S.Current->getThis();
if (!CheckThis(S, OpPC, This))
return false;
S.Stk.push<Pointer>(This.atField(Off));
return true;
}
inline bool GetPtrActiveField(InterpState &S, CodePtr OpPC, uint32_t Off) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckNull(S, OpPC, Ptr, CSK_Field))
return false;
if (!CheckRange(S, OpPC, Ptr, CSK_Field))
return false;
Pointer Field = Ptr.atField(Off);
Ptr.deactivate();
Field.activate();
S.Stk.push<Pointer>(std::move(Field));
return true;
}
inline bool GetPtrActiveThisField(InterpState &S, CodePtr OpPC, uint32_t Off) {
if (S.checkingPotentialConstantExpression())
return false;
const Pointer &This = S.Current->getThis();
if (!CheckThis(S, OpPC, This))
return false;
Pointer Field = This.atField(Off);
This.deactivate();
Field.activate();
S.Stk.push<Pointer>(std::move(Field));
return true;
}
inline bool GetPtrDerivedPop(InterpState &S, CodePtr OpPC, uint32_t Off) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckNull(S, OpPC, Ptr, CSK_Derived))
return false;
if (!CheckSubobject(S, OpPC, Ptr, CSK_Derived))
return false;
if (!CheckDowncast(S, OpPC, Ptr, Off))
return false;
S.Stk.push<Pointer>(Ptr.atFieldSub(Off));
return true;
}
inline bool GetPtrBase(InterpState &S, CodePtr OpPC, uint32_t Off) {
const Pointer &Ptr = S.Stk.peek<Pointer>();
if (!CheckNull(S, OpPC, Ptr, CSK_Base))
return false;
if (!CheckSubobject(S, OpPC, Ptr, CSK_Base))
return false;
const Pointer &Result = Ptr.atField(Off);
if (Result.isPastEnd() || !Result.isBaseClass())
return false;
S.Stk.push<Pointer>(Result);
return true;
}
inline bool GetPtrBasePop(InterpState &S, CodePtr OpPC, uint32_t Off) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckNull(S, OpPC, Ptr, CSK_Base))
return false;
if (!CheckSubobject(S, OpPC, Ptr, CSK_Base))
return false;
const Pointer &Result = Ptr.atField(Off);
if (Result.isPastEnd() || !Result.isBaseClass())
return false;
S.Stk.push<Pointer>(Result);
return true;
}
inline bool GetMemberPtrBasePop(InterpState &S, CodePtr OpPC, int32_t Off) {
const auto &Ptr = S.Stk.pop<MemberPointer>();
S.Stk.push<MemberPointer>(Ptr.atInstanceBase(Off));
return true;
}
inline bool GetPtrThisBase(InterpState &S, CodePtr OpPC, uint32_t Off) {
if (S.checkingPotentialConstantExpression())
return false;
const Pointer &This = S.Current->getThis();
if (!CheckThis(S, OpPC, This))
return false;
S.Stk.push<Pointer>(This.atField(Off));
return true;
}
inline bool FinishInitPop(InterpState &S, CodePtr OpPC) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (Ptr.canBeInitialized()) {
Ptr.initialize();
Ptr.activate();
}
return true;
}
inline bool FinishInit(InterpState &S, CodePtr OpPC) {
const Pointer &Ptr = S.Stk.peek<Pointer>();
if (Ptr.canBeInitialized()) {
Ptr.initialize();
Ptr.activate();
}
return true;
}
inline bool Dump(InterpState &S, CodePtr OpPC) {
S.Stk.dump();
return true;
}
inline bool VirtBaseHelper(InterpState &S, CodePtr OpPC, const RecordDecl *Decl,
const Pointer &Ptr) {
Pointer Base = Ptr;
while (Base.isBaseClass())
Base = Base.getBase();
const Record::Base *VirtBase = Base.getRecord()->getVirtualBase(Decl);
S.Stk.push<Pointer>(Base.atField(VirtBase->Offset));
return true;
}
inline bool GetPtrVirtBasePop(InterpState &S, CodePtr OpPC,
const RecordDecl *D) {
assert(D);
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckNull(S, OpPC, Ptr, CSK_Base))
return false;
return VirtBaseHelper(S, OpPC, D, Ptr);
}
inline bool GetPtrThisVirtBase(InterpState &S, CodePtr OpPC,
const RecordDecl *D) {
assert(D);
if (S.checkingPotentialConstantExpression())
return false;
const Pointer &This = S.Current->getThis();
if (!CheckThis(S, OpPC, This))
return false;
return VirtBaseHelper(S, OpPC, D, S.Current->getThis());
}
//===----------------------------------------------------------------------===//
// Load, Store, Init
//===----------------------------------------------------------------------===//
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool Load(InterpState &S, CodePtr OpPC) {
const Pointer &Ptr = S.Stk.peek<Pointer>();
if (!CheckLoad(S, OpPC, Ptr))
return false;
if (!Ptr.isBlockPointer())
return false;
S.Stk.push<T>(Ptr.deref<T>());
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool LoadPop(InterpState &S, CodePtr OpPC) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckLoad(S, OpPC, Ptr))
return false;
if (!Ptr.isBlockPointer())
return false;
S.Stk.push<T>(Ptr.deref<T>());
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool Store(InterpState &S, CodePtr OpPC) {
const T &Value = S.Stk.pop<T>();
const Pointer &Ptr = S.Stk.peek<Pointer>();
if (!CheckStore(S, OpPC, Ptr))
return false;
if (Ptr.canBeInitialized()) {
Ptr.initialize();
Ptr.activate();
}
Ptr.deref<T>() = Value;
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool StorePop(InterpState &S, CodePtr OpPC) {
const T &Value = S.Stk.pop<T>();
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckStore(S, OpPC, Ptr))
return false;
if (Ptr.canBeInitialized()) {
Ptr.initialize();
Ptr.activate();
}
Ptr.deref<T>() = Value;
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool StoreBitField(InterpState &S, CodePtr OpPC) {
const T &Value = S.Stk.pop<T>();
const Pointer &Ptr = S.Stk.peek<Pointer>();
if (!CheckStore(S, OpPC, Ptr))
return false;
if (Ptr.canBeInitialized())
Ptr.initialize();
if (const auto *FD = Ptr.getField())
Ptr.deref<T>() = Value.truncate(FD->getBitWidthValue(S.getCtx()));
else
Ptr.deref<T>() = Value;
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool StoreBitFieldPop(InterpState &S, CodePtr OpPC) {
const T &Value = S.Stk.pop<T>();
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckStore(S, OpPC, Ptr))
return false;
if (Ptr.canBeInitialized())
Ptr.initialize();
if (const auto *FD = Ptr.getField())
Ptr.deref<T>() = Value.truncate(FD->getBitWidthValue(S.getCtx()));
else
Ptr.deref<T>() = Value;
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool Init(InterpState &S, CodePtr OpPC) {
const T &Value = S.Stk.pop<T>();
const Pointer &Ptr = S.Stk.peek<Pointer>();
if (!CheckInit(S, OpPC, Ptr)) {
assert(false);
return false;
}
Ptr.initialize();
new (&Ptr.deref<T>()) T(Value);
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool InitPop(InterpState &S, CodePtr OpPC) {
const T &Value = S.Stk.pop<T>();
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckInit(S, OpPC, Ptr))
return false;
Ptr.initialize();
new (&Ptr.deref<T>()) T(Value);
return true;
}
/// 1) Pops the value from the stack
/// 2) Peeks a pointer and gets its index \Idx
/// 3) Sets the value on the pointer, leaving the pointer on the stack.
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool InitElem(InterpState &S, CodePtr OpPC, uint32_t Idx) {
const T &Value = S.Stk.pop<T>();
const Pointer &Ptr = S.Stk.peek<Pointer>().atIndex(Idx);
if (Ptr.isUnknownSizeArray())
return false;
if (!CheckInit(S, OpPC, Ptr))
return false;
Ptr.initialize();
new (&Ptr.deref<T>()) T(Value);
return true;
}
/// The same as InitElem, but pops the pointer as well.
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool InitElemPop(InterpState &S, CodePtr OpPC, uint32_t Idx) {
const T &Value = S.Stk.pop<T>();
const Pointer &Ptr = S.Stk.pop<Pointer>().atIndex(Idx);
if (Ptr.isUnknownSizeArray())
return false;
if (!CheckInit(S, OpPC, Ptr))
return false;
Ptr.initialize();
new (&Ptr.deref<T>()) T(Value);
return true;
}
inline bool Memcpy(InterpState &S, CodePtr OpPC) {
const Pointer &Src = S.Stk.pop<Pointer>();
Pointer &Dest = S.Stk.peek<Pointer>();
if (!CheckLoad(S, OpPC, Src))
return false;
return DoMemcpy(S, OpPC, Src, Dest);
}
inline bool ToMemberPtr(InterpState &S, CodePtr OpPC) {
const auto &Member = S.Stk.pop<MemberPointer>();
const auto &Base = S.Stk.pop<Pointer>();
S.Stk.push<MemberPointer>(Member.takeInstance(Base));
return true;
}
inline bool CastMemberPtrPtr(InterpState &S, CodePtr OpPC) {
const auto &MP = S.Stk.pop<MemberPointer>();
if (std::optional<Pointer> Ptr = MP.toPointer(S.Ctx)) {
S.Stk.push<Pointer>(*Ptr);
return true;
}
return false;
}
//===----------------------------------------------------------------------===//
// AddOffset, SubOffset
//===----------------------------------------------------------------------===//
template <class T, ArithOp Op>
bool OffsetHelper(InterpState &S, CodePtr OpPC, const T &Offset,
const Pointer &Ptr) {
// A zero offset does not change the pointer.
if (Offset.isZero()) {
S.Stk.push<Pointer>(Ptr);
return true;
}
if (!CheckNull(S, OpPC, Ptr, CSK_ArrayIndex)) {
// The CheckNull will have emitted a note already, but we only
// abort in C++, since this is fine in C.
if (S.getLangOpts().CPlusPlus)
return false;
}
// Arrays of unknown bounds cannot have pointers into them.
if (!CheckArray(S, OpPC, Ptr))
return false;
// This is much simpler for integral pointers, so handle them first.
if (Ptr.isIntegralPointer()) {
uint64_t V = Ptr.getIntegerRepresentation();
uint64_t O = static_cast<uint64_t>(Offset) * Ptr.elemSize();
if constexpr (Op == ArithOp::Add)
S.Stk.push<Pointer>(V + O, Ptr.asIntPointer().Desc);
else
S.Stk.push<Pointer>(V - O, Ptr.asIntPointer().Desc);
return true;
} else if (Ptr.isFunctionPointer()) {
uint64_t O = static_cast<uint64_t>(Offset);
uint64_t N;
if constexpr (Op == ArithOp::Add)
N = Ptr.getByteOffset() + O;
else
N = Ptr.getByteOffset() - O;
if (N > 1)
S.CCEDiag(S.Current->getSource(OpPC), diag::note_constexpr_array_index)
<< N << /*non-array*/ true << 0;
S.Stk.push<Pointer>(Ptr.asFunctionPointer().getFunction(), N);
return true;
}
assert(Ptr.isBlockPointer());
uint64_t MaxIndex = static_cast<uint64_t>(Ptr.getNumElems());
uint64_t Index;
if (Ptr.isOnePastEnd())
Index = MaxIndex;
else
Index = Ptr.getIndex();
bool Invalid = false;
// Helper to report an invalid offset, computed as APSInt.
auto DiagInvalidOffset = [&]() -> void {
const unsigned Bits = Offset.bitWidth();
APSInt APOffset(Offset.toAPSInt().extend(Bits + 2), /*IsUnsigend=*/false);
APSInt APIndex(APInt(Bits + 2, Index, /*IsSigned=*/true),
/*IsUnsigned=*/false);
APSInt NewIndex =
(Op == ArithOp::Add) ? (APIndex + APOffset) : (APIndex - APOffset);
S.CCEDiag(S.Current->getSource(OpPC), diag::note_constexpr_array_index)
<< NewIndex << /*array*/ static_cast<int>(!Ptr.inArray()) << MaxIndex;
Invalid = true;
};
if (Ptr.isBlockPointer()) {
uint64_t IOffset = static_cast<uint64_t>(Offset);
uint64_t MaxOffset = MaxIndex - Index;
if constexpr (Op == ArithOp::Add) {
// If the new offset would be negative, bail out.
if (Offset.isNegative() && (Offset.isMin() || -IOffset > Index))
DiagInvalidOffset();
// If the new offset would be out of bounds, bail out.
if (Offset.isPositive() && IOffset > MaxOffset)
DiagInvalidOffset();
} else {
// If the new offset would be negative, bail out.
if (Offset.isPositive() && Index < IOffset)
DiagInvalidOffset();
// If the new offset would be out of bounds, bail out.
if (Offset.isNegative() && (Offset.isMin() || -IOffset > MaxOffset))
DiagInvalidOffset();
}
}
if (Invalid && S.getLangOpts().CPlusPlus)
return false;
// Offset is valid - compute it on unsigned.
int64_t WideIndex = static_cast<int64_t>(Index);
int64_t WideOffset = static_cast<int64_t>(Offset);
int64_t Result;
if constexpr (Op == ArithOp::Add)
Result = WideIndex + WideOffset;
else
Result = WideIndex - WideOffset;
// When the pointer is one-past-end, going back to index 0 is the only
// useful thing we can do. Any other index has been diagnosed before and
// we don't get here.
if (Result == 0 && Ptr.isOnePastEnd()) {
S.Stk.push<Pointer>(Ptr.asBlockPointer().Pointee,
Ptr.asBlockPointer().Base);
return true;
}
S.Stk.push<Pointer>(Ptr.atIndex(static_cast<uint64_t>(Result)));
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool AddOffset(InterpState &S, CodePtr OpPC) {
const T &Offset = S.Stk.pop<T>();
const Pointer &Ptr = S.Stk.pop<Pointer>();
return OffsetHelper<T, ArithOp::Add>(S, OpPC, Offset, Ptr);
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool SubOffset(InterpState &S, CodePtr OpPC) {
const T &Offset = S.Stk.pop<T>();
const Pointer &Ptr = S.Stk.pop<Pointer>();
return OffsetHelper<T, ArithOp::Sub>(S, OpPC, Offset, Ptr);
}
template <ArithOp Op>
static inline bool IncDecPtrHelper(InterpState &S, CodePtr OpPC,
const Pointer &Ptr) {
if (Ptr.isDummy())
return false;
using OneT = Integral<8, false>;
const Pointer &P = Ptr.deref<Pointer>();
if (!CheckNull(S, OpPC, P, CSK_ArrayIndex))
return false;
// Get the current value on the stack.
S.Stk.push<Pointer>(P);
// Now the current Ptr again and a constant 1.
OneT One = OneT::from(1);
if (!OffsetHelper<OneT, Op>(S, OpPC, One, P))
return false;
// Store the new value.
Ptr.deref<Pointer>() = S.Stk.pop<Pointer>();
return true;
}
static inline bool IncPtr(InterpState &S, CodePtr OpPC) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckInitialized(S, OpPC, Ptr, AK_Increment))
return false;
return IncDecPtrHelper<ArithOp::Add>(S, OpPC, Ptr);
}
static inline bool DecPtr(InterpState &S, CodePtr OpPC) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckInitialized(S, OpPC, Ptr, AK_Decrement))
return false;
return IncDecPtrHelper<ArithOp::Sub>(S, OpPC, Ptr);
}
/// 1) Pops a Pointer from the stack.
/// 2) Pops another Pointer from the stack.
/// 3) Pushes the different of the indices of the two pointers on the stack.
template <PrimType Name, class T = typename PrimConv<Name>::T>
inline bool SubPtr(InterpState &S, CodePtr OpPC) {
const Pointer &LHS = S.Stk.pop<Pointer>();
const Pointer &RHS = S.Stk.pop<Pointer>();
for (const Pointer &P : {LHS, RHS}) {
if (P.isZeroSizeArray()) {
QualType PtrT = P.getType();
while (auto *AT = dyn_cast<ArrayType>(PtrT))
PtrT = AT->getElementType();
QualType ArrayTy = S.getCtx().getConstantArrayType(
PtrT, APInt::getZero(1), nullptr, ArraySizeModifier::Normal, 0);
S.FFDiag(S.Current->getSource(OpPC),
diag::note_constexpr_pointer_subtraction_zero_size)
<< ArrayTy;
return false;
}
}
if (RHS.isZero()) {
S.Stk.push<T>(T::from(LHS.getIndex()));
return true;
}
if (!Pointer::hasSameBase(LHS, RHS) && S.getLangOpts().CPlusPlus) {
// TODO: Diagnose.
return false;
}
if (LHS.isZero() && RHS.isZero()) {
S.Stk.push<T>();
return true;
}
T A = LHS.isBlockPointer()
? (LHS.isElementPastEnd() ? T::from(LHS.getNumElems())
: T::from(LHS.getIndex()))
: T::from(LHS.getIntegerRepresentation());
T B = RHS.isBlockPointer()
? (RHS.isElementPastEnd() ? T::from(RHS.getNumElems())
: T::from(RHS.getIndex()))
: T::from(RHS.getIntegerRepresentation());
return AddSubMulHelper<T, T::sub, std::minus>(S, OpPC, A.bitWidth(), A, B);
}
//===----------------------------------------------------------------------===//
// Destroy
//===----------------------------------------------------------------------===//
inline bool Destroy(InterpState &S, CodePtr OpPC, uint32_t I) {
S.Current->destroy(I);
return true;
}
inline bool InitScope(InterpState &S, CodePtr OpPC, uint32_t I) {
S.Current->initScope(I);
return true;
}
//===----------------------------------------------------------------------===//
// Cast, CastFP
//===----------------------------------------------------------------------===//
template <PrimType TIn, PrimType TOut> bool Cast(InterpState &S, CodePtr OpPC) {
using T = typename PrimConv<TIn>::T;
using U = typename PrimConv<TOut>::T;
S.Stk.push<U>(U::from(S.Stk.pop<T>()));
return true;
}
/// 1) Pops a Floating from the stack.
/// 2) Pushes a new floating on the stack that uses the given semantics.
inline bool CastFP(InterpState &S, CodePtr OpPC, const llvm::fltSemantics *Sem,
llvm::RoundingMode RM) {
Floating F = S.Stk.pop<Floating>();
Floating Result = F.toSemantics(Sem, RM);
S.Stk.push<Floating>(Result);
return true;
}
/// Like Cast(), but we cast to an arbitrary-bitwidth integral, so we need
/// to know what bitwidth the result should be.
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool CastAP(InterpState &S, CodePtr OpPC, uint32_t BitWidth) {
S.Stk.push<IntegralAP<false>>(
IntegralAP<false>::from(S.Stk.pop<T>(), BitWidth));
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool CastAPS(InterpState &S, CodePtr OpPC, uint32_t BitWidth) {
S.Stk.push<IntegralAP<true>>(
IntegralAP<true>::from(S.Stk.pop<T>(), BitWidth));
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool CastIntegralFloating(InterpState &S, CodePtr OpPC,
const llvm::fltSemantics *Sem,
llvm::RoundingMode RM) {
const T &From = S.Stk.pop<T>();
APSInt FromAP = From.toAPSInt();
Floating Result;
auto Status = Floating::fromIntegral(FromAP, *Sem, RM, Result);
S.Stk.push<Floating>(Result);
return CheckFloatResult(S, OpPC, Result, Status);
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool CastFloatingIntegral(InterpState &S, CodePtr OpPC) {
const Floating &F = S.Stk.pop<Floating>();
if constexpr (std::is_same_v<T, Boolean>) {
S.Stk.push<T>(T(F.isNonZero()));
return true;
} else {
APSInt Result(std::max(8u, T::bitWidth()),
/*IsUnsigned=*/!T::isSigned());
auto Status = F.convertToInteger(Result);
// Float-to-Integral overflow check.
if ((Status & APFloat::opStatus::opInvalidOp)) {
const Expr *E = S.Current->getExpr(OpPC);
QualType Type = E->getType();
S.CCEDiag(E, diag::note_constexpr_overflow) << F.getAPFloat() << Type;
if (S.noteUndefinedBehavior()) {
S.Stk.push<T>(T(Result));
return true;
}
return false;
}
S.Stk.push<T>(T(Result));
return CheckFloatResult(S, OpPC, F, Status);
}
}
static inline bool CastFloatingIntegralAP(InterpState &S, CodePtr OpPC,
uint32_t BitWidth) {
const Floating &F = S.Stk.pop<Floating>();
APSInt Result(BitWidth, /*IsUnsigned=*/true);
auto Status = F.convertToInteger(Result);
// Float-to-Integral overflow check.
if ((Status & APFloat::opStatus::opInvalidOp) && F.isFinite()) {
const Expr *E = S.Current->getExpr(OpPC);
QualType Type = E->getType();
S.CCEDiag(E, diag::note_constexpr_overflow) << F.getAPFloat() << Type;
return S.noteUndefinedBehavior();
}
S.Stk.push<IntegralAP<true>>(IntegralAP<true>(Result));
return CheckFloatResult(S, OpPC, F, Status);
}
static inline bool CastFloatingIntegralAPS(InterpState &S, CodePtr OpPC,
uint32_t BitWidth) {
const Floating &F = S.Stk.pop<Floating>();
APSInt Result(BitWidth, /*IsUnsigned=*/false);
auto Status = F.convertToInteger(Result);
// Float-to-Integral overflow check.
if ((Status & APFloat::opStatus::opInvalidOp) && F.isFinite()) {
const Expr *E = S.Current->getExpr(OpPC);
QualType Type = E->getType();
S.CCEDiag(E, diag::note_constexpr_overflow) << F.getAPFloat() << Type;
return S.noteUndefinedBehavior();
}
S.Stk.push<IntegralAP<true>>(IntegralAP<true>(Result));
return CheckFloatResult(S, OpPC, F, Status);
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool CastPointerIntegral(InterpState &S, CodePtr OpPC) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (Ptr.isDummy())
return false;
const SourceInfo &E = S.Current->getSource(OpPC);
S.CCEDiag(E, diag::note_constexpr_invalid_cast)
<< 2 << S.getLangOpts().CPlusPlus << S.Current->getRange(OpPC);
S.Stk.push<T>(T::from(Ptr.getIntegerRepresentation()));
return true;
}
static inline bool CastPointerIntegralAP(InterpState &S, CodePtr OpPC,
uint32_t BitWidth) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (Ptr.isDummy())
return false;
const SourceInfo &E = S.Current->getSource(OpPC);
S.CCEDiag(E, diag::note_constexpr_invalid_cast)
<< 2 << S.getLangOpts().CPlusPlus << S.Current->getRange(OpPC);
S.Stk.push<IntegralAP<false>>(
IntegralAP<false>::from(Ptr.getIntegerRepresentation(), BitWidth));
return true;
}
static inline bool CastPointerIntegralAPS(InterpState &S, CodePtr OpPC,
uint32_t BitWidth) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (Ptr.isDummy())
return false;
const SourceInfo &E = S.Current->getSource(OpPC);
S.CCEDiag(E, diag::note_constexpr_invalid_cast)
<< 2 << S.getLangOpts().CPlusPlus << S.Current->getRange(OpPC);
S.Stk.push<IntegralAP<true>>(
IntegralAP<true>::from(Ptr.getIntegerRepresentation(), BitWidth));
return true;
}
static inline bool PtrPtrCast(InterpState &S, CodePtr OpPC, bool SrcIsVoidPtr) {
const auto &Ptr = S.Stk.peek<Pointer>();
if (SrcIsVoidPtr && S.getLangOpts().CPlusPlus) {
bool HasValidResult = !Ptr.isZero();
if (HasValidResult) {
// FIXME: note_constexpr_invalid_void_star_cast
} else if (!S.getLangOpts().CPlusPlus26) {
const SourceInfo &E = S.Current->getSource(OpPC);
S.CCEDiag(E, diag::note_constexpr_invalid_cast)
<< 3 << "'void *'" << S.Current->getRange(OpPC);
}
} else {
const SourceInfo &E = S.Current->getSource(OpPC);
S.CCEDiag(E, diag::note_constexpr_invalid_cast)
<< 2 << S.getLangOpts().CPlusPlus << S.Current->getRange(OpPC);
}
return true;
}
//===----------------------------------------------------------------------===//
// Zero, Nullptr
//===----------------------------------------------------------------------===//
template <PrimType Name, class T = typename PrimConv<Name>::T>
bool Zero(InterpState &S, CodePtr OpPC) {
S.Stk.push<T>(T::zero());
return true;
}
static inline bool ZeroIntAP(InterpState &S, CodePtr OpPC, uint32_t BitWidth) {
S.Stk.push<IntegralAP<false>>(IntegralAP<false>::zero(BitWidth));
return true;
}
static inline bool ZeroIntAPS(InterpState &S, CodePtr OpPC, uint32_t BitWidth) {
S.Stk.push<IntegralAP<true>>(IntegralAP<true>::zero(BitWidth));
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
inline bool Null(InterpState &S, CodePtr OpPC, const Descriptor *Desc) {
// Note: Desc can be null.
S.Stk.push<T>(0, Desc);
return true;
}
//===----------------------------------------------------------------------===//
// This, ImplicitThis
//===----------------------------------------------------------------------===//
inline bool This(InterpState &S, CodePtr OpPC) {
// Cannot read 'this' in this mode.
if (S.checkingPotentialConstantExpression()) {
return false;
}
const Pointer &This = S.Current->getThis();
if (!CheckThis(S, OpPC, This))
return false;
// Ensure the This pointer has been cast to the correct base.
if (!This.isDummy()) {
assert(isa<CXXMethodDecl>(S.Current->getFunction()->getDecl()));
assert(This.getRecord());
assert(
This.getRecord()->getDecl() ==
cast<CXXMethodDecl>(S.Current->getFunction()->getDecl())->getParent());
}
S.Stk.push<Pointer>(This);
return true;
}
inline bool RVOPtr(InterpState &S, CodePtr OpPC) {
assert(S.Current->getFunction()->hasRVO());
if (S.checkingPotentialConstantExpression())
return false;
S.Stk.push<Pointer>(S.Current->getRVOPtr());
return true;
}
//===----------------------------------------------------------------------===//
// Shr, Shl
//===----------------------------------------------------------------------===//
enum class ShiftDir { Left, Right };
template <class LT, class RT, ShiftDir Dir>
inline bool DoShift(InterpState &S, CodePtr OpPC, LT &LHS, RT &RHS) {
const unsigned Bits = LHS.bitWidth();
// OpenCL 6.3j: shift values are effectively % word size of LHS.
if (S.getLangOpts().OpenCL)
RT::bitAnd(RHS, RT::from(LHS.bitWidth() - 1, RHS.bitWidth()),
RHS.bitWidth(), &RHS);
if (RHS.isNegative()) {
// During constant-folding, a negative shift is an opposite shift. Such a
// shift is not a constant expression.
const SourceInfo &Loc = S.Current->getSource(OpPC);
S.CCEDiag(Loc, diag::note_constexpr_negative_shift) << RHS.toAPSInt();
if (!S.noteUndefinedBehavior())
return false;
RHS = -RHS;
return DoShift<LT, RT,
Dir == ShiftDir::Left ? ShiftDir::Right : ShiftDir::Left>(
S, OpPC, LHS, RHS);
}
if constexpr (Dir == ShiftDir::Left) {
if (LHS.isNegative() && !S.getLangOpts().CPlusPlus20) {
// C++11 [expr.shift]p2: A signed left shift must have a non-negative
// operand, and must not overflow the corresponding unsigned type.
// C++2a [expr.shift]p2: E1 << E2 is the unique value congruent to
// E1 x 2^E2 module 2^N.
const SourceInfo &Loc = S.Current->getSource(OpPC);
S.CCEDiag(Loc, diag::note_constexpr_lshift_of_negative) << LHS.toAPSInt();
if (!S.noteUndefinedBehavior())
return false;
}
}
if (!CheckShift(S, OpPC, LHS, RHS, Bits))
return false;
// Limit the shift amount to Bits - 1. If this happened,
// it has already been diagnosed by CheckShift() above,
// but we still need to handle it.
typename LT::AsUnsigned R;
if constexpr (Dir == ShiftDir::Left) {
if (RHS > RT::from(Bits - 1, RHS.bitWidth()))
LT::AsUnsigned::shiftLeft(LT::AsUnsigned::from(LHS),
LT::AsUnsigned::from(Bits - 1), Bits, &R);
else
LT::AsUnsigned::shiftLeft(LT::AsUnsigned::from(LHS),
LT::AsUnsigned::from(RHS, Bits), Bits, &R);
} else {
if (RHS > RT::from(Bits - 1, RHS.bitWidth()))
LT::AsUnsigned::shiftRight(LT::AsUnsigned::from(LHS),
LT::AsUnsigned::from(Bits - 1), Bits, &R);
else
LT::AsUnsigned::shiftRight(LT::AsUnsigned::from(LHS),
LT::AsUnsigned::from(RHS, Bits), Bits, &R);
}
// We did the shift above as unsigned. Restore the sign bit if we need to.
if constexpr (Dir == ShiftDir::Right) {
if (LHS.isSigned() && LHS.isNegative()) {
typename LT::AsUnsigned SignBit;
LT::AsUnsigned::shiftLeft(LT::AsUnsigned::from(1, Bits),
LT::AsUnsigned::from(Bits - 1, Bits), Bits,
&SignBit);
LT::AsUnsigned::bitOr(R, SignBit, Bits, &R);
}
}
S.Stk.push<LT>(LT::from(R));
return true;
}
template <PrimType NameL, PrimType NameR>
inline bool Shr(InterpState &S, CodePtr OpPC) {
using LT = typename PrimConv<NameL>::T;
using RT = typename PrimConv<NameR>::T;
auto RHS = S.Stk.pop<RT>();
auto LHS = S.Stk.pop<LT>();
return DoShift<LT, RT, ShiftDir::Right>(S, OpPC, LHS, RHS);
}
template <PrimType NameL, PrimType NameR>
inline bool Shl(InterpState &S, CodePtr OpPC) {
using LT = typename PrimConv<NameL>::T;
using RT = typename PrimConv<NameR>::T;
auto RHS = S.Stk.pop<RT>();
auto LHS = S.Stk.pop<LT>();
return DoShift<LT, RT, ShiftDir::Left>(S, OpPC, LHS, RHS);
}
//===----------------------------------------------------------------------===//
// NoRet
//===----------------------------------------------------------------------===//
inline bool NoRet(InterpState &S, CodePtr OpPC) {
SourceLocation EndLoc = S.Current->getCallee()->getEndLoc();
S.FFDiag(EndLoc, diag::note_constexpr_no_return);
return false;
}
//===----------------------------------------------------------------------===//
// NarrowPtr, ExpandPtr
//===----------------------------------------------------------------------===//
inline bool NarrowPtr(InterpState &S, CodePtr OpPC) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
S.Stk.push<Pointer>(Ptr.narrow());
return true;
}
inline bool ExpandPtr(InterpState &S, CodePtr OpPC) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
S.Stk.push<Pointer>(Ptr.expand());
return true;
}
// 1) Pops an integral value from the stack
// 2) Peeks a pointer
// 3) Pushes a new pointer that's a narrowed array
// element of the peeked pointer with the value
// from 1) added as offset.
//
// This leaves the original pointer on the stack and pushes a new one
// with the offset applied and narrowed.
template <PrimType Name, class T = typename PrimConv<Name>::T>
inline bool ArrayElemPtr(InterpState &S, CodePtr OpPC) {
const T &Offset = S.Stk.pop<T>();
const Pointer &Ptr = S.Stk.peek<Pointer>();
if (!Ptr.isZero() && !Offset.isZero()) {
if (!CheckArray(S, OpPC, Ptr))
return false;
}
if (!OffsetHelper<T, ArithOp::Add>(S, OpPC, Offset, Ptr))
return false;
return NarrowPtr(S, OpPC);
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
inline bool ArrayElemPtrPop(InterpState &S, CodePtr OpPC) {
const T &Offset = S.Stk.pop<T>();
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!Ptr.isZero() && !Offset.isZero()) {
if (!CheckArray(S, OpPC, Ptr))
return false;
}
if (!OffsetHelper<T, ArithOp::Add>(S, OpPC, Offset, Ptr))
return false;
return NarrowPtr(S, OpPC);
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
inline bool ArrayElem(InterpState &S, CodePtr OpPC, uint32_t Index) {
const Pointer &Ptr = S.Stk.peek<Pointer>();
if (!CheckLoad(S, OpPC, Ptr))
return false;
S.Stk.push<T>(Ptr.atIndex(Index).deref<T>());
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
inline bool ArrayElemPop(InterpState &S, CodePtr OpPC, uint32_t Index) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (!CheckLoad(S, OpPC, Ptr))
return false;
S.Stk.push<T>(Ptr.atIndex(Index).deref<T>());
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
inline bool CopyArray(InterpState &S, CodePtr OpPC, uint32_t SrcIndex,
uint32_t DestIndex, uint32_t Size) {
const auto &SrcPtr = S.Stk.pop<Pointer>();
const auto &DestPtr = S.Stk.peek<Pointer>();
for (uint32_t I = 0; I != Size; ++I) {
const Pointer &SP = SrcPtr.atIndex(SrcIndex + I);
if (!CheckLoad(S, OpPC, SP))
return false;
const Pointer &DP = DestPtr.atIndex(DestIndex + I);
DP.deref<T>() = SP.deref<T>();
DP.initialize();
}
return true;
}
/// Just takes a pointer and checks if it's an incomplete
/// array type.
inline bool ArrayDecay(InterpState &S, CodePtr OpPC) {
const Pointer &Ptr = S.Stk.pop<Pointer>();
if (Ptr.isZero()) {
S.Stk.push<Pointer>(Ptr);
return true;
}
if (!CheckRange(S, OpPC, Ptr, CSK_ArrayToPointer))
return false;
if (Ptr.isRoot() || !Ptr.isUnknownSizeArray() || Ptr.isDummy()) {
S.Stk.push<Pointer>(Ptr.atIndex(0));
return true;
}
const SourceInfo &E = S.Current->getSource(OpPC);
S.FFDiag(E, diag::note_constexpr_unsupported_unsized_array);
return false;
}
inline bool CallVar(InterpState &S, CodePtr OpPC, const Function *Func,
uint32_t VarArgSize) {
if (Func->hasThisPointer()) {
size_t ArgSize = Func->getArgSize() + VarArgSize;
size_t ThisOffset = ArgSize - (Func->hasRVO() ? primSize(PT_Ptr) : 0);
const Pointer &ThisPtr = S.Stk.peek<Pointer>(ThisOffset);
// If the current function is a lambda static invoker and
// the function we're about to call is a lambda call operator,
// skip the CheckInvoke, since the ThisPtr is a null pointer
// anyway.
if (!(S.Current->getFunction() &&
S.Current->getFunction()->isLambdaStaticInvoker() &&
Func->isLambdaCallOperator())) {
if (!CheckInvoke(S, OpPC, ThisPtr))
return false;
}
if (S.checkingPotentialConstantExpression())
return false;
}
if (!CheckCallable(S, OpPC, Func))
return false;
if (!CheckCallDepth(S, OpPC))
return false;
auto NewFrame = std::make_unique<InterpFrame>(S, Func, OpPC, VarArgSize);
InterpFrame *FrameBefore = S.Current;
S.Current = NewFrame.get();
APValue CallResult;
// Note that we cannot assert(CallResult.hasValue()) here since
// Ret() above only sets the APValue if the curent frame doesn't
// have a caller set.
if (Interpret(S, CallResult)) {
NewFrame.release(); // Frame was delete'd already.
assert(S.Current == FrameBefore);
return true;
}
// Interpreting the function failed somehow. Reset to
// previous state.
S.Current = FrameBefore;
return false;
return false;
}
inline bool Call(InterpState &S, CodePtr OpPC, const Function *Func,
uint32_t VarArgSize) {
if (Func->hasThisPointer()) {
size_t ArgSize = Func->getArgSize() + VarArgSize;
size_t ThisOffset = ArgSize - (Func->hasRVO() ? primSize(PT_Ptr) : 0);
const Pointer &ThisPtr = S.Stk.peek<Pointer>(ThisOffset);
// If the current function is a lambda static invoker and
// the function we're about to call is a lambda call operator,
// skip the CheckInvoke, since the ThisPtr is a null pointer
// anyway.
if (!(S.Current->getFunction() &&
S.Current->getFunction()->isLambdaStaticInvoker() &&
Func->isLambdaCallOperator())) {
if (!CheckInvoke(S, OpPC, ThisPtr))
return false;
}
}
if (!CheckCallable(S, OpPC, Func))
return false;
if (Func->hasThisPointer() && S.checkingPotentialConstantExpression())
return false;
if (!CheckCallDepth(S, OpPC))
return false;
auto NewFrame = std::make_unique<InterpFrame>(S, Func, OpPC, VarArgSize);
InterpFrame *FrameBefore = S.Current;
S.Current = NewFrame.get();
APValue CallResult;
// Note that we cannot assert(CallResult.hasValue()) here since
// Ret() above only sets the APValue if the curent frame doesn't
// have a caller set.
if (Interpret(S, CallResult)) {
NewFrame.release(); // Frame was delete'd already.
assert(S.Current == FrameBefore);
return true;
}
// Interpreting the function failed somehow. Reset to
// previous state.
S.Current = FrameBefore;
return false;
}
inline bool CallVirt(InterpState &S, CodePtr OpPC, const Function *Func,
uint32_t VarArgSize) {
assert(Func->hasThisPointer());
assert(Func->isVirtual());
size_t ArgSize = Func->getArgSize() + VarArgSize;
size_t ThisOffset = ArgSize - (Func->hasRVO() ? primSize(PT_Ptr) : 0);
Pointer &ThisPtr = S.Stk.peek<Pointer>(ThisOffset);
const CXXRecordDecl *DynamicDecl = nullptr;
{
Pointer TypePtr = ThisPtr;
while (TypePtr.isBaseClass())
TypePtr = TypePtr.getBase();
QualType DynamicType = TypePtr.getType();
if (DynamicType->isPointerType() || DynamicType->isReferenceType())
DynamicDecl = DynamicType->getPointeeCXXRecordDecl();
else
DynamicDecl = DynamicType->getAsCXXRecordDecl();
}
assert(DynamicDecl);
const auto *StaticDecl = cast<CXXRecordDecl>(Func->getParentDecl());
const auto *InitialFunction = cast<CXXMethodDecl>(Func->getDecl());
const CXXMethodDecl *Overrider = S.getContext().getOverridingFunction(
DynamicDecl, StaticDecl, InitialFunction);
if (Overrider != InitialFunction) {
// DR1872: An instantiated virtual constexpr function can't be called in a
// constant expression (prior to C++20). We can still constant-fold such a
// call.
if (!S.getLangOpts().CPlusPlus20 && Overrider->isVirtual()) {
const Expr *E = S.Current->getExpr(OpPC);
S.CCEDiag(E, diag::note_constexpr_virtual_call) << E->getSourceRange();
}
Func = S.getContext().getOrCreateFunction(Overrider);
const CXXRecordDecl *ThisFieldDecl =
ThisPtr.getFieldDesc()->getType()->getAsCXXRecordDecl();
if (Func->getParentDecl()->isDerivedFrom(ThisFieldDecl)) {
// If the function we call is further DOWN the hierarchy than the
// FieldDesc of our pointer, just go up the hierarchy of this field
// the furthest we can go.
while (ThisPtr.isBaseClass())
ThisPtr = ThisPtr.getBase();
}
}
if (!Call(S, OpPC, Func, VarArgSize))
return false;
// Covariant return types. The return type of Overrider is a pointer
// or reference to a class type.
if (Overrider != InitialFunction &&
Overrider->getReturnType()->isPointerOrReferenceType() &&
InitialFunction->getReturnType()->isPointerOrReferenceType()) {
QualType OverriderPointeeType =
Overrider->getReturnType()->getPointeeType();
QualType InitialPointeeType =
InitialFunction->getReturnType()->getPointeeType();
// We've called Overrider above, but calling code expects us to return what
// InitialFunction returned. According to the rules for covariant return
// types, what InitialFunction returns needs to be a base class of what
// Overrider returns. So, we need to do an upcast here.
unsigned Offset = S.getContext().collectBaseOffset(
InitialPointeeType->getAsRecordDecl(),
OverriderPointeeType->getAsRecordDecl());
return GetPtrBasePop(S, OpPC, Offset);
}
return true;
}
inline bool CallBI(InterpState &S, CodePtr &PC, const Function *Func,
const CallExpr *CE) {
auto NewFrame = std::make_unique<InterpFrame>(S, Func, PC);
InterpFrame *FrameBefore = S.Current;
S.Current = NewFrame.get();
if (InterpretBuiltin(S, PC, Func, CE)) {
NewFrame.release();
return true;
}
S.Current = FrameBefore;
return false;
}
inline bool CallPtr(InterpState &S, CodePtr OpPC, uint32_t ArgSize,
const CallExpr *CE) {
const FunctionPointer &FuncPtr = S.Stk.pop<FunctionPointer>();
const Function *F = FuncPtr.getFunction();
if (!F) {
const auto *E = cast<CallExpr>(S.Current->getExpr(OpPC));
S.FFDiag(E, diag::note_constexpr_null_callee)
<< const_cast<Expr *>(E->getCallee()) << E->getSourceRange();
return false;
}
if (!FuncPtr.isValid() || !F->getDecl())
return Invalid(S, OpPC);
assert(F);
// This happens when the call expression has been cast to
// something else, but we don't support that.
if (S.Ctx.classify(F->getDecl()->getReturnType()) !=
S.Ctx.classify(CE->getType()))
return false;
// Check argument nullability state.
if (F->hasNonNullAttr()) {
if (!CheckNonNullArgs(S, OpPC, F, CE, ArgSize))
return false;
}
assert(ArgSize >= F->getWrittenArgSize());
uint32_t VarArgSize = ArgSize - F->getWrittenArgSize();
// We need to do this explicitly here since we don't have the necessary
// information to do it automatically.
if (F->isThisPointerExplicit())
VarArgSize -= align(primSize(PT_Ptr));
if (F->isVirtual())
return CallVirt(S, OpPC, F, VarArgSize);
return Call(S, OpPC, F, VarArgSize);
}
inline bool GetFnPtr(InterpState &S, CodePtr OpPC, const Function *Func) {
assert(Func);
S.Stk.push<FunctionPointer>(Func);
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
inline bool GetIntPtr(InterpState &S, CodePtr OpPC, const Descriptor *Desc) {
const T &IntVal = S.Stk.pop<T>();
S.Stk.push<Pointer>(static_cast<uint64_t>(IntVal), Desc);
return true;
}
inline bool GetMemberPtr(InterpState &S, CodePtr OpPC, const Decl *D) {
S.Stk.push<MemberPointer>(D);
return true;
}
inline bool GetMemberPtrBase(InterpState &S, CodePtr OpPC) {
const auto &MP = S.Stk.pop<MemberPointer>();
S.Stk.push<Pointer>(MP.getBase());
return true;
}
inline bool GetMemberPtrDecl(InterpState &S, CodePtr OpPC) {
const auto &MP = S.Stk.pop<MemberPointer>();
const auto *FD = cast<FunctionDecl>(MP.getDecl());
const auto *Func = S.getContext().getOrCreateFunction(FD);
S.Stk.push<FunctionPointer>(Func);
return true;
}
/// Just emit a diagnostic. The expression that caused emission of this
/// op is not valid in a constant context.
inline bool Invalid(InterpState &S, CodePtr OpPC) {
const SourceLocation &Loc = S.Current->getLocation(OpPC);
S.FFDiag(Loc, diag::note_invalid_subexpr_in_const_expr)
<< S.Current->getRange(OpPC);
return false;
}
inline bool Unsupported(InterpState &S, CodePtr OpPC) {
const SourceLocation &Loc = S.Current->getLocation(OpPC);
S.FFDiag(Loc, diag::note_constexpr_stmt_expr_unsupported)
<< S.Current->getRange(OpPC);
return false;
}
/// Do nothing and just abort execution.
inline bool Error(InterpState &S, CodePtr OpPC) { return false; }
/// Same here, but only for casts.
inline bool InvalidCast(InterpState &S, CodePtr OpPC, CastKind Kind,
bool Fatal) {
const SourceLocation &Loc = S.Current->getLocation(OpPC);
// FIXME: Support diagnosing other invalid cast kinds.
if (Kind == CastKind::Reinterpret) {
S.CCEDiag(Loc, diag::note_constexpr_invalid_cast)
<< static_cast<unsigned>(Kind) << S.Current->getRange(OpPC);
return !Fatal;
}
return false;
}
inline bool InvalidDeclRef(InterpState &S, CodePtr OpPC,
const DeclRefExpr *DR) {
assert(DR);
return CheckDeclRef(S, OpPC, DR);
}
inline bool SizelessVectorElementSize(InterpState &S, CodePtr OpPC) {
if (S.inConstantContext()) {
const SourceRange &ArgRange = S.Current->getRange(OpPC);
const Expr *E = S.Current->getExpr(OpPC);
S.CCEDiag(E, diag::note_constexpr_non_const_vectorelements) << ArgRange;
}
return false;
}
inline bool Assume(InterpState &S, CodePtr OpPC) {
const auto Val = S.Stk.pop<Boolean>();
if (Val)
return true;
// Else, diagnose.
const SourceLocation &Loc = S.Current->getLocation(OpPC);
S.CCEDiag(Loc, diag::note_constexpr_assumption_failed);
return false;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
inline bool OffsetOf(InterpState &S, CodePtr OpPC, const OffsetOfExpr *E) {
llvm::SmallVector<int64_t> ArrayIndices;
for (size_t I = 0; I != E->getNumExpressions(); ++I)
ArrayIndices.emplace_back(S.Stk.pop<int64_t>());
int64_t Result;
if (!InterpretOffsetOf(S, OpPC, E, ArrayIndices, Result))
return false;
S.Stk.push<T>(T::from(Result));
return true;
}
template <PrimType Name, class T = typename PrimConv<Name>::T>
inline bool CheckNonNullArg(InterpState &S, CodePtr OpPC) {
const T &Arg = S.Stk.peek<T>();
if (!Arg.isZero())
return true;
const SourceLocation &Loc = S.Current->getLocation(OpPC);
S.CCEDiag(Loc, diag::note_non_null_attribute_failed);
return false;
}
void diagnoseEnumValue(InterpState &S, CodePtr OpPC, const EnumDecl *ED,
const APSInt &Value);
template <PrimType Name, class T = typename PrimConv<Name>::T>
inline bool CheckEnumValue(InterpState &S, CodePtr OpPC, const EnumDecl *ED) {
assert(ED);
assert(!ED->isFixed());
const APSInt Val = S.Stk.peek<T>().toAPSInt();
if (S.inConstantContext())
diagnoseEnumValue(S, OpPC, ED, Val);
return true;
}
/// OldPtr -> Integer -> NewPtr.
template <PrimType TIn, PrimType TOut>
inline bool DecayPtr(InterpState &S, CodePtr OpPC) {
static_assert(isPtrType(TIn) && isPtrType(TOut));
using FromT = typename PrimConv<TIn>::T;
using ToT = typename PrimConv<TOut>::T;
const FromT &OldPtr = S.Stk.pop<FromT>();
if constexpr (std::is_same_v<FromT, FunctionPointer> &&
std::is_same_v<ToT, Pointer>) {
S.Stk.push<Pointer>(OldPtr.getFunction(), OldPtr.getOffset());
return true;
} else if constexpr (std::is_same_v<FromT, Pointer> &&
std::is_same_v<ToT, FunctionPointer>) {
if (OldPtr.isFunctionPointer()) {
S.Stk.push<FunctionPointer>(OldPtr.asFunctionPointer().getFunction(),
OldPtr.getByteOffset());
return true;
}
}
S.Stk.push<ToT>(ToT(OldPtr.getIntegerRepresentation(), nullptr));
return true;
}
inline bool CheckDecl(InterpState &S, CodePtr OpPC, const VarDecl *VD) {
// An expression E is a core constant expression unless the evaluation of E
// would evaluate one of the following: [C++23] - a control flow that passes
// through a declaration of a variable with static or thread storage duration
// unless that variable is usable in constant expressions.
assert(VD->isLocalVarDecl() &&
VD->isStaticLocal()); // Checked before emitting this.
if (VD == S.EvaluatingDecl)
return true;
if (!VD->isUsableInConstantExpressions(S.getCtx())) {
S.CCEDiag(VD->getLocation(), diag::note_constexpr_static_local)
<< (VD->getTSCSpec() == TSCS_unspecified ? 0 : 1) << VD;
return false;
}
return true;
}
inline bool Alloc(InterpState &S, CodePtr OpPC, const Descriptor *Desc) {
assert(Desc);
if (!CheckDynamicMemoryAllocation(S, OpPC))
return false;
DynamicAllocator &Allocator = S.getAllocator();
Block *B = Allocator.allocate(Desc, S.Ctx.getEvalID());
assert(B);
S.Stk.push<Pointer>(B, sizeof(InlineDescriptor));
return true;
}
template <PrimType Name, class SizeT = typename PrimConv<Name>::T>
inline bool AllocN(InterpState &S, CodePtr OpPC, PrimType T, const Expr *Source,
bool IsNoThrow) {
if (!CheckDynamicMemoryAllocation(S, OpPC))
return false;
SizeT NumElements = S.Stk.pop<SizeT>();
if (!CheckArraySize(S, OpPC, &NumElements, primSize(T), IsNoThrow)) {
if (!IsNoThrow)
return false;
// If this failed and is nothrow, just return a null ptr.
S.Stk.push<Pointer>(0, nullptr);
return true;
}
DynamicAllocator &Allocator = S.getAllocator();
Block *B = Allocator.allocate(Source, T, static_cast<size_t>(NumElements),
S.Ctx.getEvalID());
assert(B);
S.Stk.push<Pointer>(B, sizeof(InlineDescriptor));
return true;
}
template <PrimType Name, class SizeT = typename PrimConv<Name>::T>
inline bool AllocCN(InterpState &S, CodePtr OpPC, const Descriptor *ElementDesc,
bool IsNoThrow) {
if (!CheckDynamicMemoryAllocation(S, OpPC))
return false;
SizeT NumElements = S.Stk.pop<SizeT>();
if (!CheckArraySize(S, OpPC, &NumElements, ElementDesc->getSize(),
IsNoThrow)) {
if (!IsNoThrow)
return false;
// If this failed and is nothrow, just return a null ptr.
S.Stk.push<Pointer>(0, ElementDesc);
return true;
}
DynamicAllocator &Allocator = S.getAllocator();
Block *B = Allocator.allocate(ElementDesc, static_cast<size_t>(NumElements),
S.Ctx.getEvalID());
assert(B);
S.Stk.push<Pointer>(B, sizeof(InlineDescriptor));
return true;
}
bool RunDestructors(InterpState &S, CodePtr OpPC, const Block *B);
static inline bool Free(InterpState &S, CodePtr OpPC, bool DeleteIsArrayForm) {
if (!CheckDynamicMemoryAllocation(S, OpPC))
return false;
const Expr *Source = nullptr;
const Block *BlockToDelete = nullptr;
{
// Extra scope for this so the block doesn't have this pointer
// pointing to it when we destroy it.
const Pointer &Ptr = S.Stk.pop<Pointer>();
// Deleteing nullptr is always fine.
if (Ptr.isZero())
return true;
if (!Ptr.isRoot() || Ptr.isOnePastEnd() || Ptr.isArrayElement()) {
const SourceInfo &Loc = S.Current->getSource(OpPC);
S.FFDiag(Loc, diag::note_constexpr_delete_subobject)
<< Ptr.toDiagnosticString(S.getCtx()) << Ptr.isOnePastEnd();
return false;
}
Source = Ptr.getDeclDesc()->asExpr();
BlockToDelete = Ptr.block();
if (!CheckDeleteSource(S, OpPC, Source, Ptr))
return false;
}
assert(Source);
assert(BlockToDelete);
// Invoke destructors before deallocating the memory.
if (!RunDestructors(S, OpPC, BlockToDelete))
return false;
DynamicAllocator &Allocator = S.getAllocator();
bool WasArrayAlloc = Allocator.isArrayAllocation(Source);
const Descriptor *BlockDesc = BlockToDelete->getDescriptor();
if (!Allocator.deallocate(Source, BlockToDelete, S)) {
// Nothing has been deallocated, this must be a double-delete.
const SourceInfo &Loc = S.Current->getSource(OpPC);
S.FFDiag(Loc, diag::note_constexpr_double_delete);
return false;
}
return CheckNewDeleteForms(S, OpPC, WasArrayAlloc, DeleteIsArrayForm,
BlockDesc, Source);
}
static inline bool IsConstantContext(InterpState &S, CodePtr OpPC) {
S.Stk.push<Boolean>(Boolean::from(S.inConstantContext()));
return true;
}
inline bool CheckLiteralType(InterpState &S, CodePtr OpPC, const Type *T) {
assert(T);
assert(!S.getLangOpts().CPlusPlus23);
// C++1y: A constant initializer for an object o [...] may also invoke
// constexpr constructors for o and its subobjects even if those objects
// are of non-literal class types.
//
// C++11 missed this detail for aggregates, so classes like this:
// struct foo_t { union { int i; volatile int j; } u; };
// are not (obviously) initializable like so:
// __attribute__((__require_constant_initialization__))
// static const foo_t x = {{0}};
// because "i" is a subobject with non-literal initialization (due to the
// volatile member of the union). See:
// http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#1677
// Therefore, we use the C++1y behavior.
if (S.EvaluatingDecl)
return true;
if (S.Current->getFunction() && S.Current->getFunction()->isConstructor() &&
S.Current->getThis().getDeclDesc()->asDecl() == S.EvaluatingDecl)
return true;
const Expr *E = S.Current->getExpr(OpPC);
if (S.getLangOpts().CPlusPlus11)
S.FFDiag(E, diag::note_constexpr_nonliteral) << E->getType();
else
S.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
return false;
}
//===----------------------------------------------------------------------===//
// Read opcode arguments
//===----------------------------------------------------------------------===//
template <typename T> inline T ReadArg(InterpState &S, CodePtr &OpPC) {
if constexpr (std::is_pointer<T>::value) {
uint32_t ID = OpPC.read<uint32_t>();
return reinterpret_cast<T>(S.P.getNativePointer(ID));
} else {
return OpPC.read<T>();
}
}
template <> inline Floating ReadArg<Floating>(InterpState &S, CodePtr &OpPC) {
Floating F = Floating::deserialize(*OpPC);
OpPC += align(F.bytesToSerialize());
return F;
}
template <>
inline IntegralAP<false> ReadArg<IntegralAP<false>>(InterpState &S,
CodePtr &OpPC) {
IntegralAP<false> I = IntegralAP<false>::deserialize(*OpPC);
OpPC += align(I.bytesToSerialize());
return I;
}
template <>
inline IntegralAP<true> ReadArg<IntegralAP<true>>(InterpState &S,
CodePtr &OpPC) {
IntegralAP<true> I = IntegralAP<true>::deserialize(*OpPC);
OpPC += align(I.bytesToSerialize());
return I;
}
} // namespace interp
} // namespace clang
#endif