dolphin/Source/Core/DSPCore/Src/DSPIntCCUtil.cpp

178 lines
3.6 KiB
C++

// Copyright (C) 2003 Dolphin Project.
// This program 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, version 2.0.
// This program 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 2.0 for more details.
// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/
// Official SVN repository and contact information can be found at
// http://code.google.com/p/dolphin-emu/
// Additional copyrights go to Duddie and Tratax (c) 2004
// HELPER FUNCTIONS
#include "DSPIntCCUtil.h"
#include "DSPCore.h"
#include "DSPInterpreter.h"
namespace DSPInterpreter {
void Update_SR_Register64(s64 _Value, bool carry, bool overflow)
{
g_dsp.r[DSP_REG_SR] &= ~SR_CMP_MASK;
// 0x01
if (carry)
{
g_dsp.r[DSP_REG_SR] |= SR_CARRY;
}
// 0x02 and 0x80
if (overflow)
{
g_dsp.r[DSP_REG_SR] |= SR_OVERFLOW;
g_dsp.r[DSP_REG_SR] |= SR_OVERFLOW_SPECIAL;
}
// 0x04
if (_Value == 0)
{
g_dsp.r[DSP_REG_SR] |= SR_ARITH_ZERO;
}
// 0x08
if (_Value < 0)
{
g_dsp.r[DSP_REG_SR] |= SR_SIGN;
}
// 0x10
if (_Value != (s32)_Value)
{
g_dsp.r[DSP_REG_SR] |= SR_OVER_S32;
}
// 0x20 - Checks if top bits of m are equal, what is it good for?
if (((_Value & 0xc0000000) == 0) || ((_Value & 0xc0000000) == 0xc0000000))
{
g_dsp.r[DSP_REG_SR] |= SR_TOP2BITS;
}
}
void Update_SR_Register16(s16 _Value, bool carry, bool overflow, bool overS32)
{
g_dsp.r[DSP_REG_SR] &= ~SR_CMP_MASK;
// 0x01
if (carry)
{
g_dsp.r[DSP_REG_SR] |= SR_CARRY;
}
// 0x02 and 0x80
if (overflow)
{
g_dsp.r[DSP_REG_SR] |= SR_OVERFLOW;
g_dsp.r[DSP_REG_SR] |= SR_OVERFLOW_SPECIAL;
}
// 0x04
if (_Value == 0)
{
g_dsp.r[DSP_REG_SR] |= SR_ARITH_ZERO;
}
// 0x08
if (_Value < 0)
{
g_dsp.r[DSP_REG_SR] |= SR_SIGN;
}
// 0x10
if (overS32)
{
g_dsp.r[DSP_REG_SR] |= SR_OVER_S32;
}
// 0x20 - Checks if top bits of m are equal, what is it good for?
if ((((u16)_Value >> 14) == 0) || (((u16)_Value >> 14) == 3))
{
g_dsp.r[DSP_REG_SR] |= SR_TOP2BITS;
}
}
void Update_SR_LZ(bool value) {
if (value == true)
g_dsp.r[DSP_REG_SR] |= SR_LOGIC_ZERO;
else
g_dsp.r[DSP_REG_SR] &= ~SR_LOGIC_ZERO;
}
inline int GetMultiplyModifier()
{
return (g_dsp.r[DSP_REG_SR] & SR_MUL_MODIFY)?1:2;
}
inline bool isCarry() {
return (g_dsp.r[DSP_REG_SR] & SR_CARRY) ? true : false;
}
inline bool isLess() {
return ((g_dsp.r[DSP_REG_SR] & SR_OVERFLOW) != (g_dsp.r[DSP_REG_SR] & SR_SIGN));
}
inline bool isZero() {
return (g_dsp.r[DSP_REG_SR] & SR_ARITH_ZERO) ? true : false;
}
inline bool isLogicZero() {
return (g_dsp.r[DSP_REG_SR] & SR_LOGIC_ZERO) ? true : false;
}
//see gdsp_registers.h for flags
bool CheckCondition(u8 _Condition)
{
switch (_Condition & 0xf)
{
case 0x0: // GE - Greater Equal
return !isLess();
case 0x1: // L - Less
return isLess();
case 0x2: // G - Greater
return !isLess() && !isZero();
case 0x3: // LE - Less Equal
return isLess() || isZero();
case 0x4: // NZ - Not Zero
return !isZero();
case 0x5: // Z - Zero
return isZero();
case 0x6: // NC - Not carry
return !isCarry();
case 0x7: // C - Carry
return isCarry();
case 0xc: // LNZ - Logic Not Zero
return !isLogicZero();
case 0xd: // LZ - Logic Zero
return isLogicZero();
case 0xf: // Empty - always true.
return true;
default:
ERROR_LOG(DSPLLE, "Unknown condition check: 0x%04x", _Condition & 0xf);
return false;
}
}
} // namespace