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* somewhat proper event scheduler

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* support for timers
* fixes, additions, shit
This commit is contained in:
StapleButter
2016-12-05 17:08:24 +01:00
parent a14c01208a
commit 343797f47d
12 changed files with 488 additions and 75 deletions
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43
ARM.cpp
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@ -38,6 +38,8 @@ ARM::~ARM()
void ARM::Reset()
{
Cycles = 0;
for (int i = 0; i < 16; i++)
R[i] = 0;
@ -49,22 +51,25 @@ void ARM::Reset()
JumpTo(ExceptionBase);
}
void ARM::JumpTo(u32 addr)
void ARM::JumpTo(u32 addr, bool restorecpsr)
{
// pipeline shit
//printf("jump from %08X to %08X\n", R[15] - ((CPSR&0x20)?4:8), addr);
if (addr&1)
if (restorecpsr)
{
addr &= ~1;
RestoreCPSR();
if (CPSR & 0x20) addr |= 0x1;
else addr &= ~0x1;
}
if (addr & 0x1)
{
addr &= ~0x1;
NextInstr = Read16(addr);
R[15] = addr+2;
CPSR |= 0x20;
}
else
{
addr &= ~3;
addr &= ~0x3;
NextInstr = Read32(addr);
R[15] = addr+4;
CPSR &= ~0x20;
@ -191,49 +196,57 @@ void ARM::TriggerIRQ()
UpdateMode(oldcpsr, CPSR);
R_IRQ[2] = oldcpsr;
R[14] = R[15];// - (oldcpsr & 0x20 ? 0 : 4);
R[14] = R[15] + (oldcpsr & 0x20 ? 2 : 0);
JumpTo(ExceptionBase + 0x18);
}
s32 ARM::Execute(s32 cycles)
{
while (cycles > 0)
s32 cyclesrun = 0;
while (cyclesrun < cycles)
{
if (CPSR & 0x20) // THUMB
{
// prefetch
CurInstr = NextInstr;
NextInstr = Read16(R[15]);
//cyclesrun += MemWaitstate(0, R[15]);
R[15] += 2;
Cycles = cyclesrun;
// actually execute
u32 icode = (CurInstr >> 6);
cycles -= ARMInterpreter::THUMBInstrTable[icode](this);
cyclesrun += ARMInterpreter::THUMBInstrTable[icode](this);
}
else
{
// prefetch
CurInstr = NextInstr;
NextInstr = Read32(R[15]);
//cyclesrun += MemWaitstate(1, R[15]);
R[15] += 4;
Cycles = cyclesrun;
// actually execute
if (CheckCondition(CurInstr >> 28))
{
u32 icode = ((CurInstr >> 4) & 0xF) | ((CurInstr >> 16) & 0xFF0);
cycles -= ARMInterpreter::ARMInstrTable[icode](this);
cyclesrun += ARMInterpreter::ARMInstrTable[icode](this);
}
else if ((CurInstr & 0xFE000000) == 0xFA000000)
{
cycles -= ARMInterpreter::A_BLX_IMM(this);
cyclesrun += ARMInterpreter::A_BLX_IMM(this);
}
else
{
// not executing it. oh well
cycles -= 1; // 1S. todo: check
cyclesrun += 1; // 1S. todo: check
}
}
}
return cycles;
return cyclesrun;
}