Files
carbon-lang/executable_semantics/interpreter/heap.cpp
T
Geoff RomerandJon Meow d5124256a2 Split interpreter into smaller modules (#662)
- Move Heap and Frame/Scope to their own headers.
- Move some functions to more appropriate headers (e.g. CopyValue -> value.h).
- Define a separate Bazel rule for each header/cpp pair.
- Modify PrintValue to not print the frames of a ContinuationValue. This was necessary to break a dependency cycle between PrintValue, PrintFrame, and Action::Print.

Co-authored-by: Jon Meow <46229924+jonmeow@users.noreply.github.com>
2021-07-19 13:51:35 -07:00

67 lines
1.9 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"
namespace Carbon {
auto Heap::AllocateValue(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.
CHECK(v != nullptr);
Address a(values_.size());
values_.push_back(v);
alive_.push_back(true);
return a;
}
auto Heap::Read(const Address& a, int line_num) -> const Value* {
this->CheckAlive(a, line_num);
return values_[a.index]->GetField(a.field_path, line_num);
}
auto Heap::Write(const Address& a, const Value* v, int line_num) -> void {
CHECK(v != nullptr);
this->CheckAlive(a, line_num);
values_[a.index] = values_[a.index]->SetField(a.field_path, v, line_num);
}
void Heap::CheckAlive(const Address& address, int line_num) {
if (!alive_[address.index]) {
std::cerr << line_num << ": undefined behavior: access to dead value ";
PrintValue(values_[address.index], std::cerr);
std::cerr << std::endl;
exit(-1);
}
}
void Heap::Deallocate(const Address& address) {
CHECK(address.field_path.IsEmpty());
if (alive_[address.index]) {
alive_[address.index] = false;
} else {
std::cerr << "runtime error, deallocating an already dead value"
<< std::endl;
exit(-1);
}
}
void Heap::PrintHeap(std::ostream& out) {
for (size_t i = 0; i < values_.size(); ++i) {
PrintAddress(Address(i), out);
out << ", ";
}
}
auto Heap::PrintAddress(const Address& a, std::ostream& out) -> void {
if (!alive_[a.index]) {
out << "!!";
}
PrintValue(values_[a.index], out);
}
} // namespace Carbon