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more shit! some start of ALU emulation

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This commit is contained in:
StapleButter
2016-11-25 00:08:53 +01:00
parent f74fb2dd27
commit 97ec988dae
9 changed files with 733 additions and 80 deletions
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46
ARM.cpp
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@ -4,6 +4,27 @@
#include "ARMInterpreter.h"
u32 ARM::ConditionTable[16] =
{
0xF0F0, // EQ
0x0F0F, // NE
0xCCCC, // CS
0x3333, // CC
0xFF00, // MI
0x00FF, // PL
0xAAAA, // VS
0x5555, // VC
0x0C0C, // HI
0xF3F3, // LS
0xAA55, // GE
0x55AA, // LT
0x0A05, // GT
0xF5FA, // LE
0xFFFF, // AL
0x0000 // NE
};
ARM::ARM(u32 num)
{
// well uh
@ -20,6 +41,8 @@ void ARM::Reset()
for (int i = 0; i < 16; i++)
R[i] = 0;
CPSR = 0x000000D3;
ExceptionBase = Num ? 0x00000000 : 0xFFFF0000;
// zorp
@ -33,10 +56,16 @@ void ARM::JumpTo(u32 addr)
// TODO: THUMB!!
if (addr&1) printf("!!! THUMB JUMP\n");
addr &= ~3;
NextInstr = Read32(addr);
R[15] = addr+4;
}
void ARM::RestoreCPSR()
{
printf("TODO: restore CPSR\n");
}
s32 ARM::Execute(s32 cycles)
{
while (cycles > 0)
@ -49,9 +78,20 @@ s32 ARM::Execute(s32 cycles)
R[15] += 4;
// actually execute
if ((CurInstr & 0xF0000000) != 0xE0000000) printf("well shit\n");
u32 icode = ((CurInstr >> 4) & 0xF) | ((CurInstr >> 16) & 0xFF0);
cycles -= ARMInterpreter::ARMInstrTable[icode](this);
if (CheckCondition(CurInstr >> 28))
{
u32 icode = ((CurInstr >> 4) & 0xF) | ((CurInstr >> 16) & 0xFF0);
cycles -= ARMInterpreter::ARMInstrTable[icode](this);
}
else if ((CurInstr & 0xFE000000) == 0xFA000000)
{
cycles -= ARMInterpreter::A_BLX_IMM(this);
}
else
{
// not executing it. oh well
cycles -= 1; // 1S. todo: check
}
}
return cycles;