dynarmic/src/frontend/A32/location_descriptor.h
2020-04-23 15:45:57 +01:00

149 lines
4.9 KiB
C++

/* This file is part of the dynarmic project.
* Copyright (c) 2016 MerryMage
* SPDX-License-Identifier: 0BSD
*/
#pragma once
#include <functional>
#include <iosfwd>
#include <tuple>
#include "common/common_types.h"
#include "frontend/A32/FPSCR.h"
#include "frontend/A32/PSR.h"
#include "frontend/A32/ITState.h"
#include "frontend/ir/location_descriptor.h"
namespace Dynarmic::A32 {
/**
* LocationDescriptor describes the location of a basic block.
* The location is not solely based on the PC because other flags influence the way
* instructions should be translated. The CPSR.T flag is most notable since it
* tells us if the processor is in Thumb or Arm mode.
*/
class LocationDescriptor {
public:
// Indicates bits that should be preserved within descriptors.
static constexpr u32 CPSR_MODE_MASK = 0x0600FE20;
static constexpr u32 FPSCR_MODE_MASK = 0x07F70000;
LocationDescriptor(u32 arm_pc, PSR cpsr, FPSCR fpscr, bool single_stepping = false)
: arm_pc(arm_pc)
, cpsr(cpsr.Value() & CPSR_MODE_MASK)
, fpscr(fpscr.Value() & FPSCR_MODE_MASK)
, single_stepping(single_stepping)
{}
explicit LocationDescriptor(const IR::LocationDescriptor& o) {
arm_pc = static_cast<u32>(o.Value());
cpsr.T((o.Value() >> 32) & 1);
cpsr.E((o.Value() >> 32) & 2);
fpscr = (o.Value() >> 32) & FPSCR_MODE_MASK;
cpsr.IT(ITState{static_cast<u8>(o.Value() >> 40)});
single_stepping = (o.Value() >> 32) & 4;
}
u32 PC() const { return arm_pc; }
bool TFlag() const { return cpsr.T(); }
bool EFlag() const { return cpsr.E(); }
ITState IT() const { return cpsr.IT(); }
A32::PSR CPSR() const { return cpsr; }
A32::FPSCR FPSCR() const { return fpscr; }
bool SingleStepping() const { return single_stepping; }
bool operator == (const LocationDescriptor& o) const {
return std::tie(arm_pc, cpsr, fpscr, single_stepping) == std::tie(o.arm_pc, o.cpsr, o.fpscr, single_stepping);
}
bool operator != (const LocationDescriptor& o) const {
return !operator==(o);
}
LocationDescriptor SetPC(u32 new_arm_pc) const {
return LocationDescriptor(new_arm_pc, cpsr, fpscr, single_stepping);
}
LocationDescriptor AdvancePC(int amount) const {
return LocationDescriptor(static_cast<u32>(arm_pc + amount), cpsr, fpscr, single_stepping);
}
LocationDescriptor SetTFlag(bool new_tflag) const {
PSR new_cpsr = cpsr;
new_cpsr.T(new_tflag);
return LocationDescriptor(arm_pc, new_cpsr, fpscr, single_stepping);
}
LocationDescriptor SetEFlag(bool new_eflag) const {
PSR new_cpsr = cpsr;
new_cpsr.E(new_eflag);
return LocationDescriptor(arm_pc, new_cpsr, fpscr, single_stepping);
}
LocationDescriptor SetFPSCR(u32 new_fpscr) const {
return LocationDescriptor(arm_pc, cpsr, A32::FPSCR{new_fpscr & FPSCR_MODE_MASK}, single_stepping);
}
LocationDescriptor AdvanceIT() const {
PSR new_cpsr = cpsr;
new_cpsr.IT(new_cpsr.IT().Advance());
return LocationDescriptor(arm_pc, new_cpsr, fpscr, single_stepping);
}
LocationDescriptor SetSingleStepping(bool new_single_stepping) const {
return LocationDescriptor(arm_pc, cpsr, fpscr, new_single_stepping);
}
u64 UniqueHash() const noexcept {
// This value MUST BE UNIQUE.
// This calculation has to match up with EmitX64::EmitTerminalPopRSBHint
const u64 pc_u64 = arm_pc;
const u64 fpscr_u64 = fpscr.Value();
const u64 t_u64 = cpsr.T() ? 1 : 0;
const u64 e_u64 = cpsr.E() ? 2 : 0;
const u64 single_stepping_u64 = single_stepping ? 4 : 0;
const u64 it_u64 = u64(cpsr.IT().Value()) << 8;
const u64 upper = (fpscr_u64 | t_u64 | e_u64 | single_stepping_u64 | it_u64) << 32;
return pc_u64 | upper;
}
operator IR::LocationDescriptor() const {
return IR::LocationDescriptor{UniqueHash()};
}
private:
u32 arm_pc; ///< Current program counter value.
PSR cpsr; ///< Current program status register.
A32::FPSCR fpscr; ///< Floating point status control register.
bool single_stepping;
};
/**
* Provides a string representation of a LocationDescriptor.
*
* @param o Output stream
* @param descriptor The descriptor to get a string representation of
*/
std::ostream& operator<<(std::ostream& o, const LocationDescriptor& descriptor);
} // namespace Dynarmic::A32
namespace std {
template <>
struct less<Dynarmic::A32::LocationDescriptor> {
bool operator()(const Dynarmic::A32::LocationDescriptor& x, const Dynarmic::A32::LocationDescriptor& y) const noexcept {
return x.UniqueHash() < y.UniqueHash();
}
};
template <>
struct hash<Dynarmic::A32::LocationDescriptor> {
size_t operator()(const Dynarmic::A32::LocationDescriptor& x) const noexcept {
return std::hash<u64>()(x.UniqueHash());
}
};
} // namespace std