melonDS/src/ARMInterpreter.cpp

252 lines
6.4 KiB
C++

/*
Copyright 2016-2021 Arisotura
This file is part of melonDS.
melonDS is free software: you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation, either version 3 of the License, or (at your option)
any later version.
melonDS is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along
with melonDS. If not, see http://www.gnu.org/licenses/.
*/
#include <stdio.h>
#include "NDS.h"
#include "ARMInterpreter.h"
#include "ARMInterpreter_ALU.h"
#include "ARMInterpreter_Branch.h"
#include "ARMInterpreter_LoadStore.h"
namespace ARMInterpreter
{
void A_UNK(ARM* cpu)
{
printf("undefined ARM%d instruction %08X @ %08X\n", cpu->Num?7:9, cpu->CurInstr, cpu->R[15]-8);
//for (int i = 0; i < 16; i++) printf("R%d: %08X\n", i, cpu->R[i]);
//NDS::Halt();
u32 oldcpsr = cpu->CPSR;
cpu->CPSR &= ~0xBF;
cpu->CPSR |= 0x9B;
cpu->UpdateMode(oldcpsr, cpu->CPSR);
cpu->R_UND[2] = oldcpsr;
cpu->R[14] = cpu->R[15] - 4;
cpu->JumpTo(cpu->ExceptionBase + 0x04);
}
void T_UNK(ARM* cpu)
{
printf("undefined THUMB%d instruction %04X @ %08X\n", cpu->Num?7:9, cpu->CurInstr, cpu->R[15]-4);
//NDS::Halt();
u32 oldcpsr = cpu->CPSR;
cpu->CPSR &= ~0xBF;
cpu->CPSR |= 0x9B;
cpu->UpdateMode(oldcpsr, cpu->CPSR);
cpu->R_UND[2] = oldcpsr;
cpu->R[14] = cpu->R[15] - 2;
cpu->JumpTo(cpu->ExceptionBase + 0x04);
}
void A_MSR_IMM(ARM* cpu)
{
u32* psr;
if (cpu->CurInstr & (1<<22))
{
switch (cpu->CPSR & 0x1F)
{
case 0x11: psr = &cpu->R_FIQ[7]; break;
case 0x12: psr = &cpu->R_IRQ[2]; break;
case 0x13: psr = &cpu->R_SVC[2]; break;
case 0x17: psr = &cpu->R_ABT[2]; break;
case 0x1B: psr = &cpu->R_UND[2]; break;
default: printf("bad CPU mode %08X\n", cpu->CPSR); return;
}
}
else
psr = &cpu->CPSR;
u32 oldpsr = *psr;
u32 mask = 0;
if (cpu->CurInstr & (1<<16)) mask |= 0x000000FF;
if (cpu->CurInstr & (1<<17)) mask |= 0x0000FF00;
if (cpu->CurInstr & (1<<18)) mask |= 0x00FF0000;
if (cpu->CurInstr & (1<<19)) mask |= 0xFF000000;
if (!(cpu->CurInstr & (1<<22)))
mask &= 0xFFFFFFDF;
if ((cpu->CPSR & 0x1F) == 0x10) mask &= 0xFFFFFF00;
u32 val = ROR((cpu->CurInstr & 0xFF), ((cpu->CurInstr >> 7) & 0x1E));
*psr &= ~mask;
*psr |= (val & mask);
if (!(cpu->CurInstr & (1<<22)))
cpu->UpdateMode(oldpsr, cpu->CPSR);
cpu->AddCycles_C();
}
void A_MSR_REG(ARM* cpu)
{
u32* psr;
if (cpu->CurInstr & (1<<22))
{
switch (cpu->CPSR & 0x1F)
{
case 0x11: psr = &cpu->R_FIQ[7]; break;
case 0x12: psr = &cpu->R_IRQ[2]; break;
case 0x13: psr = &cpu->R_SVC[2]; break;
case 0x17: psr = &cpu->R_ABT[2]; break;
case 0x1B: psr = &cpu->R_UND[2]; break;
default: printf("bad CPU mode %08X\n", cpu->CPSR); return;
}
}
else
psr = &cpu->CPSR;
u32 oldpsr = *psr;
u32 mask = 0;
if (cpu->CurInstr & (1<<16)) mask |= 0x000000FF;
if (cpu->CurInstr & (1<<17)) mask |= 0x0000FF00;
if (cpu->CurInstr & (1<<18)) mask |= 0x00FF0000;
if (cpu->CurInstr & (1<<19)) mask |= 0xFF000000;
if (!(cpu->CurInstr & (1<<22)))
mask &= 0xFFFFFFDF;
if ((cpu->CPSR & 0x1F) == 0x10) mask &= 0xFFFFFF00;
u32 val = cpu->R[cpu->CurInstr & 0xF];
*psr &= ~mask;
*psr |= (val & mask);
if (!(cpu->CurInstr & (1<<22)))
cpu->UpdateMode(oldpsr, cpu->CPSR);
cpu->AddCycles_C();
}
void A_MRS(ARM* cpu)
{
u32 psr;
if (cpu->CurInstr & (1<<22))
{
switch (cpu->CPSR & 0x1F)
{
case 0x11: psr = cpu->R_FIQ[7]; break;
case 0x12: psr = cpu->R_IRQ[2]; break;
case 0x13: psr = cpu->R_SVC[2]; break;
case 0x17: psr = cpu->R_ABT[2]; break;
case 0x1B: psr = cpu->R_UND[2]; break;
default: printf("bad CPU mode %08X\n", cpu->CPSR); return;
}
}
else
psr = cpu->CPSR;
cpu->R[(cpu->CurInstr>>12) & 0xF] = psr;
cpu->AddCycles_C();
}
void A_MCR(ARM* cpu)
{
u32 cp = (cpu->CurInstr >> 8) & 0xF;
//u32 op = (cpu->CurInstr >> 21) & 0x7;
u32 cn = (cpu->CurInstr >> 16) & 0xF;
u32 cm = cpu->CurInstr & 0xF;
u32 cpinfo = (cpu->CurInstr >> 5) & 0x7;
if (cpu->Num==0 && cp==15)
{
((ARMv5*)cpu)->CP15Write((cn<<8)|(cm<<4)|cpinfo, cpu->R[(cpu->CurInstr>>12)&0xF]);
}
else if (cpu->Num==1 && cp==14)
{
printf("MCR p14,%d,%d,%d on ARM7\n", cn, cm, cpinfo);
}
else
{
printf("bad MCR opcode p%d,%d,%d,%d on ARM%d\n", cp, cn, cm, cpinfo, cpu->Num?7:9);
return A_UNK(cpu); // TODO: check what kind of exception it really is
}
cpu->AddCycles_CI(1 + 1); // TODO: checkme
}
void A_MRC(ARM* cpu)
{
u32 cp = (cpu->CurInstr >> 8) & 0xF;
//u32 op = (cpu->CurInstr >> 21) & 0x7;
u32 cn = (cpu->CurInstr >> 16) & 0xF;
u32 cm = cpu->CurInstr & 0xF;
u32 cpinfo = (cpu->CurInstr >> 5) & 0x7;
if (cpu->Num==0 && cp==15)
{
cpu->R[(cpu->CurInstr>>12)&0xF] = ((ARMv5*)cpu)->CP15Read((cn<<8)|(cm<<4)|cpinfo);
}
else if (cpu->Num==1 && cp==14)
{
printf("MRC p14,%d,%d,%d on ARM7\n", cn, cm, cpinfo);
}
else
{
printf("bad MRC opcode p%d,%d,%d,%d on ARM%d\n", cp, cn, cm, cpinfo, cpu->Num?7:9);
return A_UNK(cpu); // TODO: check what kind of exception it really is
}
cpu->AddCycles_CI(2 + 1); // TODO: checkme
}
void A_SVC(ARM* cpu)
{
u32 oldcpsr = cpu->CPSR;
cpu->CPSR &= ~0xBF;
cpu->CPSR |= 0x93;
cpu->UpdateMode(oldcpsr, cpu->CPSR);
cpu->R_SVC[2] = oldcpsr;
cpu->R[14] = cpu->R[15] - 4;
cpu->JumpTo(cpu->ExceptionBase + 0x08);
}
void T_SVC(ARM* cpu)
{
u32 oldcpsr = cpu->CPSR;
cpu->CPSR &= ~0xBF;
cpu->CPSR |= 0x93;
cpu->UpdateMode(oldcpsr, cpu->CPSR);
cpu->R_SVC[2] = oldcpsr;
cpu->R[14] = cpu->R[15] - 2;
cpu->JumpTo(cpu->ExceptionBase + 0x08);
}
#define INSTRFUNC_PROTO(x) void (*x)(ARM* cpu)
#include "ARM_InstrTable.h"
#undef INSTRFUNC_PROTO
}