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Minor optimizations to speedhacks patching
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@esmjanus
esmjanus committed Aug 19, 2017
1 parent 67f9372 commit 501fa91
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Showing 4 changed files with 138 additions and 129 deletions.
244 changes: 125 additions & 119 deletions cpuops.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -2933,7 +2933,7 @@ inline void CPUShutdown() {

if (CPU.WaitCounter == 0 && !(CPU.Flags & (IRQ_PENDING_FLAG | NMI_FLAG))) {
CPU.WaitAddress = NULL;
if (Settings.SA1) S9xSA1ExecuteDuringSleep ();
//if (Settings.SA1) S9xSA1ExecuteDuringSleep ();

if ((IAPU_APUExecuting)) {
if (CPU.Cycles>CPU.NextEvent) {
Expand Down Expand Up @@ -4599,75 +4599,44 @@ static void OpCB (void)
// Speedhack for main CPU
// Based on snes9x 3DS
//
static void CPUSpeedhack (void) {
static void CPUSpeedhack (void)
{
#ifndef SA1_OPCODES
bool doSkip = false;
// If there's any pending NMI/IRQ don't speed hack
//
if (((CPU.Flags & NMI_FLAG) && (CPU.NMICycleCount - 1 == 0)) ||
((CPU.Flags & IRQ_PENDING_FLAG) && (CPU.IRQCycleCount == 0)))
doSkip = false;
else
{
doSkip = false;
if (!CPU.Flags)
doSkip = true;
else if ((CPU.Flags & IRQ_PENDING_FLAG) && (CPU.IRQCycleCount == 0) && CheckFlag (IRQ))
doSkip = true;
}

int foundHackIndex = -1;

// Search for the appropriate speed hack
//
uint8* prevCPUPC = (uint8 *)(CPU.PC - 1);

// Make sure we check again SpeedHackCount.
//
for (int i = 0; i < SNESGameFixes.SpeedHackCount; i++)
{
if (SNESGameFixes.SpeedHackAddress[i] == prevCPUPC)
{
foundHackIndex = i;
break;
CPU.WaitAddress = NULL;
if ((IAPU_APUExecuting)) {
if (CPU.Cycles>CPU.NextEvent) {
cpu_glob_cycles += CPU.Cycles-old_cpu_cycles;
old_cpu_cycles=CPU.NextEvent;
}
}

// Some games actually use NOP. So we must ensure
// That this is a registered speed hack
//
if (foundHackIndex == -1)
{
// If we can't find the speed hack, then
// we will treat this like a NOP (as it was before)
//
doSkip = false;
return;
CPU.Cycles = CPU.NextEvent;

if ((IAPU_APUExecuting)) {
ICPU.CPUExecuting = FALSE;

UPDATE_APU_COUNTER();

ICPU.CPUExecuting = TRUE;
}

/*if (Settings.SA1)
if (SA1.Executing)
doSkip = false;*/

// Executes the original opcode that we replaced.
//
(*ICPU.S9xOpcodes [SNESGameFixes.SpeedHackOriginalOpcode[foundHackIndex]].S9xOpcode) ();
(*ICPU.S9xOpcodes [SNESGameFixes.SpeedHackOriginalOpcode[0]].S9xOpcode) ();

// If we decide to skip, then we add cycles to the CPU.Cycles
// until just before the next event.
//
if (doSkip)
{
int cyclesToSkip = SNESGameFixes.SpeedHackCycles[foundHackIndex];
int cyclesToSkip = SNESGameFixes.SpeedHackCycles[0];

if (cyclesToSkip == -1)
CPU.Cycles = CPU.NextEvent;
else
if (cyclesToSkip == -1)
CPU.Cycles = CPU.NextEvent;
else
{
while (CPU.Cycles + cyclesToSkip < CPU.NextEvent)
{
while (CPU.Cycles + cyclesToSkip < CPU.NextEvent)
{
CPU.Cycles = CPU.Cycles + cyclesToSkip;
}
CPU.Cycles = CPU.Cycles + cyclesToSkip;
}
}
#endif
Expand All @@ -4676,88 +4645,103 @@ static void CPUSpeedhack (void) {
// Speedhack for SA1 games
// Based on snes9x 3DS
//
static void SA1Speedhack (void) {
static void SA1Speedhack (void)
{
#ifdef SA1_OPCODES
bool doSkip = false;
int foundHackIndex = -1;

// Search for the appropriate speed hack
//
uint8* prevCPUPC = (uint8*)(CPU.PC - 1);

// Make sure we check again SpeedHackCount.
// Executes the original opcode that we replaced.
//
doSkip = true;
for (int i = 0; i < SNESGameFixes.SpeedHackSA1Count; i++)
{
if (SNESGameFixes.SpeedHackSA1Address[i] == prevCPUPC)
{
foundHackIndex = i;
break;
(*ICPU.S9xOpcodes [SNESGameFixes.SpeedHackSA1OriginalOpcode[0]].S9xOpcode) ();

if (SA1.WaitCounter == 0)
SA1.Executing = false;
else
SA1.WaitCounter--;

#endif
}

// SNESAdvance speedhack used on Opcode 0xDB (based on the speed-hacks branch of CatSFC)
//
static void SNESAdvance_OpDB (void)
{
#ifndef SA1_OPCODES
uint8 NextByte;

CPU.WaitAddress = NULL;
if ((IAPU_APUExecuting)) {
if (CPU.Cycles>CPU.NextEvent) {
cpu_glob_cycles += CPU.Cycles-old_cpu_cycles;
old_cpu_cycles=CPU.NextEvent;
}
}

// Some games actually use NOP. So we must ensure
// That this is a registered speed hack
//
if (foundHackIndex == -1)
{
// If we can't find the speed hack, then
// we will treat this like a NOP (as it was before)
//
doSkip = false;
return;
CPU.Cycles = CPU.NextEvent;

if ((IAPU_APUExecuting)) {
ICPU.CPUExecuting = FALSE;

UPDATE_APU_COUNTER();

ICPU.CPUExecuting = TRUE;
}

// Executes the original opcode that we replaced.
//
(*ICPU.S9xOpcodes [SNESGameFixes.SpeedHackSA1OriginalOpcode[foundHackIndex]].S9xOpcode) ();
NextByte = *CPU.PC++;

int8 BranchOffset = (NextByte & 0x7F) | ((NextByte & 0x40) << 1);
// ^ -64 .. +63, sign extend bit 6 into 7 for unpacking
long OpAddress = ((int) (CPU.PC - CPU.PCBase) + BranchOffset) & 0xffff;

if (doSkip)
switch (NextByte & 0x80)
{
if (SA1.WaitCounter == 0)
SA1.Executing = false;
else
SA1.WaitCounter--;
case 0x00: // BNE
BranchCheck();
if (!CheckZero ()) {
CPU.PC = CPU.PCBase + OpAddress;
#ifdef VAR_CYCLES
CPU.Cycles += ONE_CYCLE;
#else
#ifndef SA1_OPCODES
CPU.Cycles++;
#endif
#endif
CPUShutdown ();
}
return;
case 0x80: // BEQ
BranchCheck();
if (CheckZero ()) {
CPU.PC = CPU.PCBase + OpAddress;
#ifdef VAR_CYCLES
CPU.Cycles += ONE_CYCLE;
#else
#ifndef SA1_OPCODES
CPU.Cycles++;
#endif
#endif
CPUShutdown ();
}
return;
}
#endif
}

// STP
// Since snes9xTYL already uses opcode 0x42 to apply speedhacks from snesadvance.dat.
// We use opcode 0xDB instead of 0x42 to apply harcoded speedhacks ported from snes9x 3DS.
// With this change we avoid graphical glitches, crashes and black screens on several games.
static void OpDB (void)
// SNESAdvance speedhack used on Opcode 0x42 (based on the speed-hacks branch of CatSFC)
//
static void SNESAdvance_Op42 (void)
{
if (Settings.SpeedHack)
{
CPUSpeedhack();
SA1Speedhack();
}
else
{
CPU.PC--;
CPU.Flags |= DEBUG_MODE_FLAG;
}
}

// SNESAdvance speedhack
static void Op42 (void) {
#ifndef SA1_OPCODES
#ifndef SA1_OPCODES

uint8 b;

CPU.WaitAddress = NULL;
if (Settings.SA1) S9xSA1ExecuteDuringSleep ();

if ((IAPU_APUExecuting)) {
if (CPU.Cycles>CPU.NextEvent) {
cpu_glob_cycles += CPU.Cycles-old_cpu_cycles;
old_cpu_cycles=CPU.NextEvent;
}
}
if ((IAPU_APUExecuting)) {
if (CPU.Cycles>CPU.NextEvent) {
cpu_glob_cycles += CPU.Cycles-old_cpu_cycles;
old_cpu_cycles=CPU.NextEvent;
}
}

CPU.Cycles = CPU.NextEvent;
CPU.Cycles = CPU.NextEvent;

/* S9xUpdateAPUTimer();*/

Expand All @@ -4777,7 +4761,7 @@ static void Op42 (void) {
#ifdef VAR_CYCLES
CPU.Cycles += CPU.MemSpeed;
#endif
long OpAddress = ((int) (CPU.PC - CPU.PCBase) + s9xInt8) & 0xffff;
long OpAddress = ((int) (CPU.PC - CPU.PCBase) + s9xInt8) & 0xffff;

switch (b&0xF0) {
case 0x10: //BPL
Expand Down Expand Up @@ -4908,6 +4892,28 @@ static void Op42 (void) {
#endif
}

// STP
// Since snes9xTYL already uses opcode 0x42 to apply speedhacks from snesadvance.dat.
// We use opcode 0xDB instead of 0x42 to apply harcoded main CPU speedhacks ported from snes9x 3DS.
// With this change we avoid graphical glitches, crashes and black screens on several games.
static void OpDB (void)
{
if (Settings.SpeedHack)
CPUSpeedhack();
else
SNESAdvance_OpDB();
//CPU.PC--;
//CPU.Flags |= DEBUG_MODE_FLAG;
}

static void Op42 (void)
{
// It seems that applying SA1 speedhacks on opcode 0x42 don't give any trouble.
// With this we avoid to apply an speedhack twice on every frame.
SA1Speedhack();
SNESAdvance_Op42();
}

/**********************************************************************************************/

/**********************************************************************************************/
Expand Down
17 changes: 10 additions & 7 deletions memmap.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -3493,7 +3493,7 @@ bool CMemory::SpeedHackAdd(int address, int cyclesPerSkip, int16 originalByte1,
}

// Applies a speed hack at the given the PB:PC location.
// It replaces the first byte with the STP (0xDB) opcode.
// It replaces the first byte with the WDM (0x42) opcode.
// Code from snes9x 3DS
bool CMemory::SpeedHackSA1Add(int address, int16 originalByte1, int16 originalByte2, int16 originalByte3, int16 originalByte4)
{
Expand Down Expand Up @@ -3561,24 +3561,26 @@ void CMemory::ApplySpeedHackPatches()
*SNESGameFixes.SpeedHackAddress[n] = 0xDB;
}
}

for (int n = 0; n < SNESGameFixes.SpeedHackSA1Count; n++)

//Since there is just one SA1 speedhack that will be applied, I'll remove the 'for' cycle for now
//for (int n = 0; n < SNESGameFixes.SpeedHackSA1Count; n++)
if(SNESGameFixes.SpeedHackSA1Count)
{
// First check that the original bytes matches.
//
bool allMatches = true;
for (int i = 0; i < 4 && SNESGameFixes.SpeedHackSA1OriginalBytes[n][i] != -1; i++)
for (int i = 0; i < 4 && SNESGameFixes.SpeedHackSA1OriginalBytes[0][i] != -1; i++)
{
uint8 byte = GetByte(SNESGameFixes.SpeedHackSA1SNESAddress[n] + i);
if (SNESGameFixes.SpeedHackSA1OriginalBytes[n][i] != byte)
uint8 byte = GetByte(SNESGameFixes.SpeedHackSA1SNESAddress[0] + i);
if (SNESGameFixes.SpeedHackSA1OriginalBytes[0][i] != byte)
{
allMatches = false;
break;
}
}

if (allMatches){
*SNESGameFixes.SpeedHackSA1Address[n] = 0xDB;
*SNESGameFixes.SpeedHackSA1Address[0] = 0x42;
}
}
}
Expand Down Expand Up @@ -4215,6 +4217,7 @@ if (ROM [adr] == ov) \
// Based on snes9x 3DS

SNESGameFixes.SpeedHackCount = 0;
SNESGameFixes.SpeedHackSA1Count = 0;
Settings.SpeedHack = false;
int instructionSet = 0;

Expand Down
4 changes: 2 additions & 2 deletions sa1.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -509,7 +509,7 @@ void S9xSA1SetPCBase (uint32 address)
}
}

void S9xSA1ExecuteDuringSleep ()
/*void S9xSA1ExecuteDuringSleep ()
{
#if 0
if (SA1.Executing)
Expand All @@ -521,7 +521,7 @@ void S9xSA1ExecuteDuringSleep ()
}
}
#endif
}
}*/

void S9xSetSA1MemMap (uint32 which1, uint8 map)
{
Expand Down
2 changes: 1 addition & 1 deletion sa1.h
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Original file line number Diff line number Diff line change
Expand Up @@ -151,7 +151,7 @@ void S9xSA1MainLoop ();
void S9xSA1CheckIRQ ();
void S9xSA1Init ();
void S9xFixSA1AfterSnapshotLoad ();
void S9xSA1ExecuteDuringSleep ();
//void S9xSA1ExecuteDuringSleep ();

INLINE uint8 S9xSA1GetByteFast (uint32 address)
{
Expand Down

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