ladybird/Userland/Libraries/LibWasm/AbstractMachine/Configuration.cpp
Ali Mohammad Pur 3926eab3b7 LibWasm+LibWeb: Implement (a very basic version of) the JS link/import
This allows Wasm code to call javascript functions.
2021-05-26 15:34:13 +04:30

103 lines
3.2 KiB
C++

/*
* Copyright (c) 2021, Ali Mohammad Pur <mpfard@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibWasm/AbstractMachine/Configuration.h>
#include <LibWasm/AbstractMachine/Interpreter.h>
namespace Wasm {
Optional<Label> Configuration::nth_label(size_t i)
{
for (size_t index = m_stack.size(); index > 0; --index) {
auto& entry = m_stack.entries()[index - 1];
if (auto ptr = entry.get_pointer<NonnullOwnPtr<Label>>()) {
if (i == 0)
return **ptr;
--i;
}
}
return {};
}
Result Configuration::call(FunctionAddress address, Vector<Value> arguments)
{
auto* function = m_store.get(address);
if (!function)
return Trap {};
if (auto* wasm_function = function->get_pointer<WasmFunction>()) {
Vector<Value> locals;
locals.ensure_capacity(arguments.size() + wasm_function->code().locals().size());
for (auto& value : arguments)
locals.append(Value { value });
for (auto& type : wasm_function->code().locals())
locals.empend(type, 0ull);
auto frame = make<Frame>(
wasm_function->module(),
move(locals),
wasm_function->code().body(),
wasm_function->type().results().size());
set_frame(move(frame));
return execute();
}
// It better be a host function, else something is really wrong.
auto& host_function = function->get<HostFunction>();
return host_function.function()(*this, arguments);
}
Result Configuration::execute()
{
Interpreter interpreter;
interpreter.interpret(*this);
if (interpreter.did_trap())
return Trap {};
Vector<NonnullOwnPtr<Value>> results;
for (size_t i = 0; i < m_current_frame->arity(); ++i)
results.append(move(stack().pop().get<NonnullOwnPtr<Value>>()));
auto label = stack().pop();
// ASSERT: label == current frame
if (!label.has<NonnullOwnPtr<Label>>())
return Trap {};
Vector<Value> results_moved;
results_moved.ensure_capacity(results.size());
for (auto& entry : results)
results_moved.unchecked_append(move(*entry));
return Result { move(results_moved) };
}
void Configuration::dump_stack()
{
for (const auto& entry : stack().entries()) {
entry.visit(
[](const NonnullOwnPtr<Value>& v) {
v->value().visit([]<typename T>(const T& v) {
if constexpr (IsIntegral<T> || IsFloatingPoint<T>)
dbgln(" {}", v);
else
dbgln(" *{}", v.value());
});
},
[](const NonnullOwnPtr<Frame>& f) {
dbgln(" frame({})", f->arity());
for (auto& local : f->locals()) {
local.value().visit([]<typename T>(const T& v) {
if constexpr (IsIntegral<T> || IsFloatingPoint<T>)
dbgln(" {}", v);
else
dbgln(" *{}", v.value());
});
}
},
[](const NonnullOwnPtr<Label>& l) {
dbgln(" label({}) -> {}", l->arity(), l->continuation());
});
}
}
}