Files
carbon-lang/executable_semantics/interpreter/heap.cpp
T
Jon Meow ffa4e76ede Add underscores to private data members (#898)
This is the last PR I plan to have focused on #720
2021-10-19 14:27:10 -07:00

69 lines
2.0 KiB
C++

// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
// Exceptions. See /LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "executable_semantics/interpreter/heap.h"
#include "executable_semantics/common/error.h"
#include "llvm/ADT/StringExtras.h"
namespace Carbon {
auto Heap::AllocateValue(Nonnull<const Value*> v) -> Address {
// Putting the following two side effects together in this function
// ensures that we don't do anything else in between, which is really bad!
// Consider whether to include a copy of the input v in this function
// or to leave it up to the caller.
Address a(values_.size());
values_.push_back(v);
alive_.push_back(true);
return a;
}
auto Heap::Read(const Address& a, SourceLocation source_loc)
-> Nonnull<const Value*> {
this->CheckAlive(a, source_loc);
return values_[a.index_]->GetField(arena_, a.field_path_, source_loc);
}
void Heap::Write(const Address& a, Nonnull<const Value*> v,
SourceLocation source_loc) {
this->CheckAlive(a, source_loc);
values_[a.index_] =
values_[a.index_]->SetField(arena_, a.field_path_, v, source_loc);
}
void Heap::CheckAlive(const Address& address, SourceLocation source_loc) {
if (!alive_[address.index_]) {
FATAL_RUNTIME_ERROR(source_loc)
<< "undefined behavior: access to dead value "
<< *values_[address.index_];
}
}
void Heap::Deallocate(const Address& address) {
CHECK(address.field_path_.IsEmpty());
if (alive_[address.index_]) {
alive_[address.index_] = false;
} else {
FATAL_RUNTIME_ERROR_NO_LINE() << "deallocating an already dead value";
}
}
void Heap::Print(llvm::raw_ostream& out) const {
llvm::ListSeparator sep;
for (size_t i = 0; i < values_.size(); ++i) {
out << sep;
PrintAddress(Address(i), out);
}
}
void Heap::PrintAddress(const Address& a, llvm::raw_ostream& out) const {
if (!alive_[a.index_]) {
out << "!!";
}
out << *values_[a.index_];
}
} // namespace Carbon