ppsspp/Core/MIPS/MIPSCodeUtils.cpp
2013-05-26 16:24:58 -07:00

103 lines
2.2 KiB
C++

// Copyright (c) 2012- PPSSPP 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 or later versions.
// 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 git repository and contact information can be found at
// https://github.com/hrydgard/ppsspp and http://www.ppsspp.org/.
#include "MIPS.h"
#include "MIPSTables.h"
#include "MIPSCodeUtils.h"
#include "../Host.h"
namespace MIPSCodeUtils
{
#define FULLOP_JR_RA 0x03e00008
#define OP_SYSCALL 0x0000000c
#define OP_SYSCALL_MASK 0xFC00003F
u32 GetJumpTarget(u32 addr)
{
u32 op = Memory::Read_Instruction(addr);
if (op)
{
op &= 0xFC000000;
if (op == 0x0C000000 || op == 0x08000000) //jal
{
u32 target = (addr & 0xF0000000) | ((op&0x03FFFFFF) << 2);
return target;
}
else
return INVALIDTARGET;
}
else
return INVALIDTARGET;
}
u32 GetBranchTarget(u32 addr)
{
u32 op = Memory::Read_Instruction(addr);
if (op)
{
u32 info = MIPSGetInfo(op);
if (info & IS_CONDBRANCH)
{
return addr + ((signed short)(op&0xFFFF)<<2);
}
else
return INVALIDTARGET;
}
else
return INVALIDTARGET;
}
u32 GetBranchTargetNoRA(u32 addr)
{
u32 op = Memory::Read_Instruction(addr);
if (op)
{
u32 info = MIPSGetInfo(op);
if ((info & IS_CONDBRANCH) && !(info & OUT_RA))
{
return addr + ((signed short)(op&0xFFFF)<<2);
}
else
return INVALIDTARGET;
}
else
return INVALIDTARGET;
}
u32 GetSureBranchTarget(u32 addr)
{
u32 op = Memory::Read_Instruction(addr);
if (op)
{
u32 info = MIPSGetInfo(op);
if (info & IS_CONDBRANCH)
{
//TODO: safer check
if ((op & 0xFFFF0000) == 0x10000000)
return addr + ((signed short)(op&0xFFFF)<<2);
else
return INVALIDTARGET;
}
else
return INVALIDTARGET;
}
else
return INVALIDTARGET;
}
}