mirrors/dynarmic
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

backend/x64: Add fastmem support to Windows exception handler

Browse source
This commit is contained in:
MerryMage 2020-04-09 09:51:10 +01:00
parent b7b71d65c2
commit 4e83e81e58
1 changed files with 62 additions and 28 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

90
src/backend/x64/exception_handler_windows.cpp
View file

@ -13,6 +13,7 @@
#include "backend/x64/block_of_code.h" #include "backend/x64/block_of_code.h"
#include "backend/x64/exception_handler.h" #include "backend/x64/exception_handler.h"
#include "common/assert.h" #include "common/assert.h"
#include "common/cast_util.h"
#include "common/common_types.h" #include "common/common_types.h"
using UBYTE = u8; using UBYTE = u8;
@ -67,6 +68,12 @@ struct UNWIND_INFO {
UBYTE FrameOffset : 4; UBYTE FrameOffset : 4;
// UNWIND_CODE UnwindCode[]; // UNWIND_CODE UnwindCode[];
// With Flags == 0 there are no additional fields. // With Flags == 0 there are no additional fields.
// OPTIONAL UNW_EXCEPTION_INFO ExceptionInfo;
};
struct UNW_EXCEPTION_INFO {
ULONG ExceptionHandler;
// OPTIONAL ARBITRARY HandlerData;
}; };
namespace Dynarmic::Backend::X64 { namespace Dynarmic::Backend::X64 {
@ -158,8 +165,55 @@ static PrologueInformation GetPrologueInformation() {
} }
struct ExceptionHandler::Impl final { struct ExceptionHandler::Impl final {
Impl(RUNTIME_FUNCTION* rfuncs_, const u8* base_ptr) : rfuncs(rfuncs_) { Impl(BlockOfCode& code) {
RtlAddFunctionTable(rfuncs, 1, reinterpret_cast<DWORD64>(base_ptr)); const auto prolog_info = GetPrologueInformation();
code.align(16);
const u8* exception_handler = code.getCurr<u8*>();
// Our 3rd argument is a PCONTEXT.
code.sub(code.rsp, 8);
code.mov(code.ABI_PARAM1, Common::BitCast<u64>(&cb));
code.mov(code.ABI_PARAM2, code.ABI_PARAM3);
code.CallLambda(
[](const std::function<FakeCall(u64)>& cb_, PCONTEXT ctx){
FakeCall fc = cb_(ctx->Rip);
ctx->Rsp -= sizeof(u64);
*Common::BitCast<u64*>(ctx->Rsp) = fc.ret_rip;
ctx->Rip = fc.call_rip;
}
);
code.add(code.rsp, 8);
code.mov(code.eax, static_cast<u32>(ExceptionContinueExecution));
code.ret();
code.align(16);
UNWIND_INFO* unwind_info = static_cast<UNWIND_INFO*>(code.AllocateFromCodeSpace(sizeof(UNWIND_INFO)));
unwind_info->Version = 1;
unwind_info->Flags = UNW_FLAG_EHANDLER;
unwind_info->SizeOfProlog = prolog_info.prolog_size;
unwind_info->CountOfCodes = static_cast<UBYTE>(prolog_info.number_of_unwind_code_entries);
unwind_info->FrameRegister = 0; // No frame register present
unwind_info->FrameOffset = 0; // Unused because FrameRegister == 0
// UNWIND_INFO::UnwindCode field:
const size_t size_of_unwind_code = sizeof(UNWIND_CODE) * prolog_info.unwind_code.size();
UNWIND_CODE* unwind_code = static_cast<UNWIND_CODE*>(code.AllocateFromCodeSpace(size_of_unwind_code));
memcpy(unwind_code, prolog_info.unwind_code.data(), size_of_unwind_code);
// UNWIND_INFO::ExceptionInfo field:
UNW_EXCEPTION_INFO* except_info = static_cast<UNW_EXCEPTION_INFO*>(code.AllocateFromCodeSpace(sizeof(UNW_EXCEPTION_INFO)));
except_info->ExceptionHandler = static_cast<ULONG>(exception_handler - code.getCode<u8*>());
code.align(16);
rfuncs = static_cast<RUNTIME_FUNCTION*>(code.AllocateFromCodeSpace(sizeof(RUNTIME_FUNCTION)));
rfuncs->BeginAddress = static_cast<DWORD>(0);
rfuncs->EndAddress = static_cast<DWORD>(code.GetTotalCodeSize());
rfuncs->UnwindData = static_cast<DWORD>(reinterpret_cast<u8*>(unwind_info) - code.getCode());
RtlAddFunctionTable(rfuncs, 1, reinterpret_cast<DWORD64>(code.getCode()));
}
void SetCallback(std::function<FakeCall(u64)> new_cb) {
cb = new_cb;
} }
~Impl() { ~Impl() {
@ -167,43 +221,23 @@ struct ExceptionHandler::Impl final {
} }
private: private:
RUNTIME_FUNCTION* rfuncs = nullptr; RUNTIME_FUNCTION* rfuncs;
std::function<FakeCall(u64)> cb;
}; };
ExceptionHandler::ExceptionHandler() = default; ExceptionHandler::ExceptionHandler() = default;
ExceptionHandler::~ExceptionHandler() = default; ExceptionHandler::~ExceptionHandler() = default;
void ExceptionHandler::Register(BlockOfCode& code) { void ExceptionHandler::Register(BlockOfCode& code) {
const auto prolog_info = GetPrologueInformation(); impl = std::make_unique<Impl>(code);
code.align(16);
UNWIND_INFO* unwind_info = static_cast<UNWIND_INFO*>(code.AllocateFromCodeSpace(sizeof(UNWIND_INFO)));
unwind_info->Version = 1;
unwind_info->Flags = 0; // No special exception handling required.
unwind_info->SizeOfProlog = prolog_info.prolog_size;
unwind_info->CountOfCodes = static_cast<UBYTE>(prolog_info.number_of_unwind_code_entries);
unwind_info->FrameRegister = 0; // No frame register present
unwind_info->FrameOffset = 0; // Unused because FrameRegister == 0
// UNWIND_INFO::UnwindCode field:
const size_t size_of_unwind_code = sizeof(UNWIND_CODE) * prolog_info.unwind_code.size();
UNWIND_CODE* unwind_code = static_cast<UNWIND_CODE*>(code.AllocateFromCodeSpace(size_of_unwind_code));
memcpy(unwind_code, prolog_info.unwind_code.data(), size_of_unwind_code);
code.align(16);
RUNTIME_FUNCTION* rfuncs = static_cast<RUNTIME_FUNCTION*>(code.AllocateFromCodeSpace(sizeof(RUNTIME_FUNCTION)));
rfuncs->BeginAddress = static_cast<DWORD>(0);
rfuncs->EndAddress = static_cast<DWORD>(code.GetTotalCodeSize());
rfuncs->UnwindData = static_cast<DWORD>(reinterpret_cast<u8*>(unwind_info) - code.getCode());
impl = std::make_unique<Impl>(rfuncs, code.getCode());
} }
bool ExceptionHandler::SupportsFastmem() const noexcept { bool ExceptionHandler::SupportsFastmem() const noexcept {
return false; return static_cast<bool>(impl);
} }
void ExceptionHandler::SetFastmemCallback(std::function<FakeCall(u64)>) { void ExceptionHandler::SetFastmemCallback(std::function<FakeCall(u64)> cb) {
// Do nothing impl->SetCallback(cb);
} }
} // namespace Dynarmic::Backend::X64 } // namespace Dynarmic::Backend::X64