// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
#include <array>
#include <map>
#include <span>
#include <boost/icl/interval_set.hpp>
#include <dynarmic/interface/A64/a64.h>
#include <dynarmic/interface/A64/config.h>
#include "common/alignment.h"
#include "common/common_funcs.h"
#include "common/div_ceil.h"
#include "common/elf.h"
#include "common/logging/log.h"
#include "core/hle/service/jit/jit_context.h"
#include "core/memory.h"
using namespace Common::ELF;
namespace Service::JIT {
constexpr std::array<u8, 8> SVC0_ARM64 = {
0x01, 0x00, 0x00, 0xd4, // svc #0
0xc0, 0x03, 0x5f, 0xd6, // ret
};
constexpr std::array HELPER_FUNCTIONS{
"_stop", "_resolve", "_panic", "memcpy", "memmove", "memset",
};
constexpr size_t STACK_ALIGN = 16;
class JITContextImpl;
using IntervalSet = boost::icl::interval_set<VAddr>::type;
using IntervalType = boost::icl::interval_set<VAddr>::interval_type;
class DynarmicCallbacks64 : public Dynarmic::A64::UserCallbacks {
public:
explicit DynarmicCallbacks64(Core::Memory::Memory& memory_, std::vector<u8>& local_memory_,
IntervalSet& mapped_ranges_, JITContextImpl& parent_)
: memory{memory_}, local_memory{local_memory_},
mapped_ranges{mapped_ranges_}, parent{parent_} {}
u8 MemoryRead8(u64 vaddr) override {
return ReadMemory<u8>(vaddr);
}
u16 MemoryRead16(u64 vaddr) override {
return ReadMemory<u16>(vaddr);
}
u32 MemoryRead32(u64 vaddr) override {
return ReadMemory<u32>(vaddr);
}
u64 MemoryRead64(u64 vaddr) override {
return ReadMemory<u64>(vaddr);
}
u128 MemoryRead128(u64 vaddr) override {
return ReadMemory<u128>(vaddr);
}
std::string MemoryReadCString(u64 vaddr) {
std::string result;
u8 next;
while ((next = MemoryRead8(vaddr++)) != 0) {
result += next;
}
return result;
}
void MemoryWrite8(u64 vaddr, u8 value) override {
WriteMemory<u8>(vaddr, value);
}
void MemoryWrite16(u64 vaddr, u16 value) override {
WriteMemory<u16>(vaddr, value);
}
void MemoryWrite32(u64 vaddr, u32 value) override {
WriteMemory<u32>(vaddr, value);
}
void MemoryWrite64(u64 vaddr, u64 value) override {
WriteMemory<u64>(vaddr, value);
}
void MemoryWrite128(u64 vaddr, u128 value) override {
WriteMemory<u128>(vaddr, value);
}
bool MemoryWriteExclusive8(u64 vaddr, u8 value, u8) override {
return WriteMemory<u8>(vaddr, value);
}
bool MemoryWriteExclusive16(u64 vaddr, u16 value, u16) override {
return WriteMemory<u16>(vaddr, value);
}
bool MemoryWriteExclusive32(u64 vaddr, u32 value, u32) override {
return WriteMemory<u32>(vaddr, value);
}
bool MemoryWriteExclusive64(u64 vaddr, u64 value, u64) override {
return WriteMemory<u64>(vaddr, value);
}
bool MemoryWriteExclusive128(u64 vaddr, u128 value, u128) override {
return WriteMemory<u128>(vaddr, value);
}
void CallSVC(u32 swi) override;
void ExceptionRaised(u64 pc, Dynarmic::A64::Exception exception) override;
void InterpreterFallback(u64 pc, size_t num_instructions) override;
void AddTicks(u64 ticks) override {}
u64 GetTicksRemaining() override {
return std::numeric_limits<u32>::max();
}
u64 GetCNTPCT() override {
return 0;
}
template <class T>
T ReadMemory(u64 vaddr) {
T ret{};
if (boost::icl::contains(mapped_ranges, vaddr)) {
memory.ReadBlock(vaddr, &ret, sizeof(T));
} else if (vaddr + sizeof(T) > local_memory.size()) {
LOG_CRITICAL(Service_JIT, "plugin: unmapped read @ 0x{:016x}", vaddr);
} else {
std::memcpy(&ret, local_memory.data() + vaddr, sizeof(T));
}
return ret;
}
template <class T>
bool WriteMemory(u64 vaddr, const T value) {
if (boost::icl::contains(mapped_ranges, vaddr)) {
memory.WriteBlock(vaddr, &value, sizeof(T));
} else if (vaddr + sizeof(T) > local_memory.size()) {
LOG_CRITICAL(Service_JIT, "plugin: unmapped write @ 0x{:016x}", vaddr);
} else {
std::memcpy(local_memory.data() + vaddr, &value, sizeof(T));
}
return true;
}
private:
Core::Memory::Memory& memory;
std::vector<u8>& local_memory;
IntervalSet& mapped_ranges;
JITContextImpl& parent;
};
class JITContextImpl {
public:
explicit JITContextImpl(Core::Memory::Memory& memory_) : memory{memory_} {
callbacks =
std::make_unique<DynarmicCallbacks64>(memory, local_memory, mapped_ranges, *this);
user_config.callbacks = callbacks.get();
jit = std::make_unique<Dynarmic::A64::Jit>(user_config);
}
bool LoadNRO(std::span<const u8> data) {
local_memory.clear();
local_memory.insert(local_memory.end(), data.begin(), data.end());
if (FixupRelocations()) {
InsertHelperFunctions();
InsertStack();
return true;
}
return false;
}
bool FixupRelocations() {
// The loaded NRO file has ELF relocations that must be processed before it can run.
// Normally this would be processed by RTLD, but in HLE context, we don't have
// the linker available, so we have to do it ourselves.
const VAddr mod_offset{callbacks->MemoryRead32(4)};
if (callbacks->MemoryRead32(mod_offset) != Common::MakeMagic('M', 'O', 'D', '0')) {
return false;
}
// For more info about dynamic entries, see the ELF ABI specification:
// https://refspecs.linuxbase.org/elf/gabi4+/ch5.dynamic.html
// https://refspecs.linuxbase.org/elf/gabi4+/ch4.reloc.html
VAddr dynamic_offset{mod_offset + callbacks->MemoryRead32(mod_offset + 4)};
VAddr rela_dyn = 0;
size_t num_rela = 0;
while (true) {
const auto dyn{callbacks->ReadMemory<Elf64_Dyn>(dynamic_offset)};
dynamic_offset += sizeof(Elf64_Dyn);
if (!dyn.d_tag) {
break;
}
if (dyn.d_tag == ElfDtRela) {
rela_dyn = dyn.d_un.d_ptr;
}
if (dyn.d_tag == ElfDtRelasz) {
num_rela = dyn.d_un.d_val / sizeof(Elf64_Rela);
}
}
for (size_t i = 0; i < num_rela; i++) {
const auto rela{callbacks->ReadMemory<Elf64_Rela>(rela_dyn + i * sizeof(Elf64_Rela))};
if (Elf64RelType(rela.r_info) != ElfAArch64Relative) {
continue;
}
const VAddr contents{callbacks->MemoryRead64(rela.r_offset)};
callbacks->MemoryWrite64(rela.r_offset, contents + rela.r_addend);
}
return true;
}
void InsertHelperFunctions() {
for (const auto& name : HELPER_FUNCTIONS) {
helpers[name] = local_memory.size();
local_memory.insert(local_memory.end(), SVC0_ARM64.begin(), SVC0_ARM64.end());
}
}
void InsertStack() {
// Allocate enough space to avoid any reasonable risk of
// overflowing the stack during plugin execution
const u64 pad_amount{Common::AlignUp(local_memory.size(), STACK_ALIGN) -
local_memory.size()};
local_memory.insert(local_memory.end(), 0x10000 + pad_amount, 0);
top_of_stack = local_memory.size();
heap_pointer = top_of_stack;
}
void MapProcessMemory(VAddr dest_address, std::size_t size) {
mapped_ranges.add(IntervalType{dest_address, dest_address + size});
}
void PushArgument(const void* data, size_t size) {
const size_t num_words = Common::DivCeil(size, sizeof(u64));
const size_t current_pos = argument_stack.size();
argument_stack.insert(argument_stack.end(), num_words, 0);
std::memcpy(argument_stack.data() + current_pos, data, size);
}
void SetupArguments() {
// The first 8 integer registers are used for the first 8 integer
// arguments. Floating-point arguments are not handled at this time.
//
// If a function takes more than 8 arguments, then stack space is reserved
// for the remaining arguments, and the remaining arguments are inserted in
// ascending memory order, each argument aligned to an 8-byte boundary. The
// stack pointer must remain aligned to 16 bytes.
//
// For more info, see the AArch64 ABI PCS:
// https://github.com/ARM-software/abi-aa/blob/main/aapcs64/aapcs64.rst
for (size_t i = 0; i < 8 && i < argument_stack.size(); i++) {
jit->SetRegister(i, argument_stack[i]);
}
if (argument_stack.size() > 8) {
const VAddr new_sp = Common::AlignDown(
top_of_stack - (argument_stack.size() - 8) * sizeof(u64), STACK_ALIGN);
for (size_t i = 8; i < argument_stack.size(); i++) {
callbacks->MemoryWrite64(new_sp + (i - 8) * sizeof(u64), argument_stack[i]);
}
jit->SetSP(new_sp);
}
// Reset the call state for the next invocation
argument_stack.clear();
heap_pointer = top_of_stack;
}
u64 CallFunction(VAddr func) {
jit->SetRegister(30, helpers["_stop"]);
jit->SetSP(top_of_stack);
SetupArguments();
jit->SetPC(func);
jit->Run();
return jit->GetRegister(0);
}
VAddr GetHelper(const std::string& name) {
return helpers[name];
}
VAddr AddHeap(const void* data, size_t size) {
// Require all heap data types to have the same alignment as the
// stack pointer, for compatibility
const size_t num_bytes{Common::AlignUp(size, STACK_ALIGN)};
// Make additional memory space if required
if (heap_pointer + num_bytes > local_memory.size()) {
local_memory.insert(local_memory.end(),
(heap_pointer + num_bytes) - local_memory.size(), 0);
}
const VAddr location{heap_pointer};
std::memcpy(local_memory.data() + location, data, size);
heap_pointer += num_bytes;
return location;
}
void GetHeap(VAddr location, void* data, size_t size) {
std::memcpy(data, local_memory.data() + location, size);
}
std::unique_ptr<DynarmicCallbacks64> callbacks;
std::vector<u8> local_memory;
std::vector<u64> argument_stack;
IntervalSet mapped_ranges;
Dynarmic::A64::UserConfig user_config;
std::unique_ptr<Dynarmic::A64::Jit> jit;
std::map<std::string, VAddr, std::less<>> helpers;
Core::Memory::Memory& memory;
VAddr top_of_stack;
VAddr heap_pointer;
};
void DynarmicCallbacks64::CallSVC(u32 swi) {
// Service calls are used to implement helper functionality.
//
// The most important of these is the _stop helper, which transfers control
// from the plugin back to HLE context to return a value. However, a few more
// are also implemented to reduce the need for direct ARM implementations of
// basic functionality, like memory operations.
//
// When we receive a helper request, the swi number will be zero, and the call
// will have originated from an address we know is a helper function. Otherwise,
// the plugin may be trying to issue a service call, which we shouldn't handle.
if (swi != 0) {
LOG_CRITICAL(Service_JIT, "plugin issued unknown service call {}", swi);
parent.jit->HaltExecution();
return;
}
u64 pc{parent.jit->GetPC() - 4};
auto& helpers{parent.helpers};
if (pc == helpers["memcpy"] || pc == helpers["memmove"]) {
const VAddr dest{parent.jit->GetRegister(0)};
const VAddr src{parent.jit->GetRegister(1)};
const size_t n{parent.jit->GetRegister(2)};
if (dest < src) {
for (size_t i = 0; i < n; i++) {
MemoryWrite8(dest + i, MemoryRead8(src + i));
}
} else {
for (size_t i = n; i > 0; i--) {
MemoryWrite8(dest + i - 1, MemoryRead8(src + i - 1));
}
}
} else if (pc == helpers["memset"]) {
const VAddr dest{parent.jit->GetRegister(0)};
const u64 c{parent.jit->GetRegister(1)};
const size_t n{parent.jit->GetRegister(2)};
for (size_t i = 0; i < n; i++) {
MemoryWrite8(dest + i, static_cast<u8>(c));
}
} else if (pc == helpers["_resolve"]) {
// X0 contains a char* for a symbol to resolve
const auto name{MemoryReadCString(parent.jit->GetRegister(0))};
const auto helper{helpers[name]};
if (helper != 0) {
parent.jit->SetRegister(0, helper);
} else {
LOG_WARNING(Service_JIT, "plugin requested unknown function {}", name);
parent.jit->SetRegister(0, helpers["_panic"]);
}
} else if (pc == helpers["_stop"]) {
parent.jit->HaltExecution();
} else if (pc == helpers["_panic"]) {
LOG_CRITICAL(Service_JIT, "plugin panicked!");
parent.jit->HaltExecution();
} else {
LOG_CRITICAL(Service_JIT, "plugin issued syscall at unknown address 0x{:x}", pc);
parent.jit->HaltExecution();
}
}
void DynarmicCallbacks64::ExceptionRaised(u64 pc, Dynarmic::A64::Exception exception) {
LOG_CRITICAL(Service_JIT, "Illegal operation PC @ {:08x}", pc);
parent.jit->HaltExecution();
}
void DynarmicCallbacks64::InterpreterFallback(u64 pc, size_t num_instructions) {
LOG_CRITICAL(Service_JIT, "Unimplemented instruction PC @ {:08x}", pc);
parent.jit->HaltExecution();
}
JITContext::JITContext(Core::Memory::Memory& memory)
: impl{std::make_unique<JITContextImpl>(memory)} {}
JITContext::~JITContext() {}
bool JITContext::LoadNRO(std::span<const u8> data) {
return impl->LoadNRO(data);
}
void JITContext::MapProcessMemory(VAddr dest_address, std::size_t size) {
impl->MapProcessMemory(dest_address, size);
}
u64 JITContext::CallFunction(VAddr func) {
return impl->CallFunction(func);
}
void JITContext::PushArgument(const void* data, size_t size) {
impl->PushArgument(data, size);
}
VAddr JITContext::GetHelper(const std::string& name) {
return impl->GetHelper(name);
}
VAddr JITContext::AddHeap(const void* data, size_t size) {
return impl->AddHeap(data, size);
}
void JITContext::GetHeap(VAddr location, void* data, size_t size) {
impl->GetHeap(location, data, size);
}
} // namespace Service::JIT