dynarmic/src/backend_x64/routines.cpp

77 lines
2.5 KiB
C++

/* This file is part of the dynarmic project.
* Copyright (c) 2016 MerryMage
* This software may be used and distributed according to the terms of the GNU
* General Public License version 2 or any later version.
*/
#include <limits>
#include "backend_x64/jitstate.h"
#include "backend_x64/routines.h"
#include "common/x64/abi.h"
using namespace Gen;
namespace Dynarmic {
namespace BackendX64 {
Routines::Routines() {
AllocCodeSpace(1024);
GenConstants();
GenRunCode();
}
size_t Routines::RunCode(JitState* jit_state, CodePtr basic_block, size_t cycles_to_run) const {
constexpr size_t max_cycles_to_run = static_cast<size_t>(std::numeric_limits<decltype(jit_state->cycles_remaining)>::max());
ASSERT(cycles_to_run <= max_cycles_to_run);
jit_state->cycles_remaining = cycles_to_run;
run_code(jit_state, basic_block);
return cycles_to_run - jit_state->cycles_remaining; // Return number of cycles actually run.
}
void Routines::GenConstants() {
const_FloatNegativeZero32 = AlignCode16();
Write32(0x80000000u);
const_FloatNaN32 = AlignCode16();
Write32(0x7fc00000u);
const_FloatNegativeZero64 = AlignCode16();
Write64(0x8000000000000000u);
const_FloatNaN64 = AlignCode16();
Write64(0x7ff8000000000000u);
const_FloatNonSignMask64 = AlignCode16();
Write64(0x7fffffffffffffffu);
const_FloatPenultimatePositiveDenormal64 = AlignCode16();
Write64(0x000ffffffffffffeu);
AlignCode16();
}
void Routines::GenRunCode() {
run_code = reinterpret_cast<RunCodeFuncType>(const_cast<u8*>(this->GetCodePtr()));
// This serves two purposes:
// 1. It saves all the registers we as a callee need to save.
// 2. It aligns the stack so that the code the JIT emits can assume
// that the stack is appropriately aligned for CALLs.
ABI_PushRegistersAndAdjustStack(ABI_ALL_CALLEE_SAVED, 8);
MOV(64, R(R15), R(ABI_PARAM1));
MOV(64, MDisp(R15, offsetof(JitState, save_host_RSP)), R(RSP));
STMXCSR(MDisp(R15, offsetof(JitState, save_host_MXCSR)));
LDMXCSR(MDisp(R15, offsetof(JitState, guest_MXCSR)));
JMPptr(R(ABI_PARAM2));
}
void Routines::GenReturnFromRunCode(XEmitter* code) const {
code->STMXCSR(MDisp(R15, offsetof(JitState, guest_MXCSR)));
code->LDMXCSR(MDisp(R15, offsetof(JitState, save_host_MXCSR)));
code->MOV(64, R(RSP), MDisp(R15, offsetof(JitState, save_host_RSP)));
code->ABI_PopRegistersAndAdjustStack(ABI_ALL_CALLEE_SAVED, 8);
code->RET();
}
} // namespace BackendX64
} // namespace Dynarmic