llvm-project/clang/lib/AST/Interp/InterpState.cpp

75 lines
2.0 KiB
C++

//===--- InterpState.cpp - 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
//
//===----------------------------------------------------------------------===//
#include "InterpState.h"
#include <limits>
#include "Function.h"
#include "InterpFrame.h"
#include "InterpStack.h"
#include "Opcode.h"
#include "PrimType.h"
#include "Program.h"
#include "State.h"
using namespace clang;
using namespace clang::interp;
using APSInt = llvm::APSInt;
InterpState::InterpState(State &Parent, Program &P, InterpStack &Stk,
Context &Ctx, SourceMapper *M)
: Parent(Parent), M(M), P(P), Stk(Stk), Ctx(Ctx), Current(nullptr),
CallStackDepth(Parent.getCallStackDepth() + 1) {}
InterpState::~InterpState() {
while (Current) {
InterpFrame *Next = Current->Caller;
delete Current;
Current = Next;
}
while (DeadBlocks) {
DeadBlock *Next = DeadBlocks->Next;
free(DeadBlocks);
DeadBlocks = Next;
}
}
Frame *InterpState::getCurrentFrame() {
if (Current && Current->Caller) {
return Current;
} else {
return Parent.getCurrentFrame();
}
}
bool InterpState::reportOverflow(const Expr *E, const llvm::APSInt &Value) {
QualType Type = E->getType();
CCEDiag(E, diag::note_constexpr_overflow) << Value << Type;
return noteUndefinedBehavior();
}
void InterpState::deallocate(Block *B) {
Descriptor *Desc = B->getDescriptor();
if (B->hasPointers()) {
size_t Size = B->getSize();
// Allocate a new block, transferring over pointers.
char *Memory = reinterpret_cast<char *>(malloc(sizeof(DeadBlock) + Size));
auto *D = new (Memory) DeadBlock(DeadBlocks, B);
// Move data from one block to another.
if (Desc->MoveFn)
Desc->MoveFn(B, B->data(), D->data(), Desc);
} else {
// Free storage, if necessary.
if (Desc->DtorFn)
Desc->DtorFn(B, B->data(), Desc);
}
}