beetle-psx-libretro/mednafen/masmem.h
2012-08-15 21:26:44 +02:00

210 lines
4.2 KiB
C++

#ifndef __MDFN_PSX_MASMEM_H
#define __MDFN_PSX_MASMEM_H
// TODO, WIP (big-endian stores and loads not fully supported yet)
#ifdef LSB_FIRST
#define MAS_NATIVE_IS_BIGENDIAN 0
#else
#define MAS_NATIVE_IS_BIGENDIAN 1
#endif
static INLINE uint16 LoadU16_RBO(const uint16 *a)
{
#ifdef ARCH_POWERPC
uint16 tmp;
__asm__ ("lhbrx %0, %y1" : "=r"(tmp) : "Z"(*a));
return(tmp);
#else
uint16 tmp = *a;
return((tmp << 8) | (tmp >> 8));
#endif
}
static INLINE uint32 LoadU32_RBO(const uint32 *a)
{
#ifdef ARCH_POWERPC
uint32 tmp;
__asm__ ("lwbrx %0, %y1" : "=r"(tmp) : "Z"(*a));
return(tmp);
#else
uint32 tmp = *a;
return((tmp << 24) | ((tmp & 0xFF00) << 8) | ((tmp >> 8) & 0xFF00) | (tmp >> 24));
#endif
}
static INLINE void StoreU16_RBO(uint16 *a, const uint16 v)
{
#ifdef ARCH_POWERPC
__asm__ ("sthbrx %0, %y1" : : "r"(v), "Z"(*a));
#else
uint16 tmp = (v << 8) | (v >> 8);
*a = tmp;
#endif
}
static INLINE void StoreU32_RBO(uint32 *a, const uint32 v)
{
#ifdef ARCH_POWERPC
__asm__ ("stwbrx %0, %y1" : : "r"(v), "Z"(*a));
#else
uint32 tmp = (v << 24) | ((v & 0xFF00) << 8) | ((v >> 8) & 0xFF00) | (v >> 24);
*a = tmp;
#endif
}
static INLINE uint16 LoadU16_LE(const uint16 *a)
{
#ifdef MSB_FIRST
return LoadU16_RBO(a);
#else
return *a;
#endif
}
static INLINE uint32 LoadU32_LE(const uint32 *a)
{
#ifdef MSB_FIRST
return LoadU32_RBO(a);
#else
return *a;
#endif
}
static INLINE void StoreU16_LE(uint16 *a, const uint16 v)
{
#ifdef MSB_FIRST
StoreU16_RBO(a, v);
#else
*a = v;
#endif
}
static INLINE void StoreU32_LE(uint32 *a, const uint32 v)
{
#ifdef MSB_FIRST
StoreU32_RBO(a, v);
#else
*a = v;
#endif
}
// address must not be >= size specified by template parameter, and address must be a multiple of the byte-size of the
// unit(1,2,4) being read(except for Read/WriteU24, which only needs to be byte-aligned).
//
// max_unit_type should be uint16 or uint32
//
// pre_padding and post_padding are specified in units of sizeof(max_unit_type).
//
template<unsigned size, typename max_unit_type, bool big_endian> //, unsigned pre_padding_count, unsigned post_padding_count>
struct MultiAccessSizeMem
{
//max_unit_type pre_padding[pre_padding_count ? pre_padding_count : 1];
union
{
uint8 data8[size];
uint16 data16[size / sizeof(uint16)];
uint32 data32[size / sizeof(uint32)];
};
//max_unit_type post_padding[post_padding_count ? post_padding_count : 1];
INLINE uint8 ReadU8(uint32 address)
{
return data8[address];
}
INLINE uint16 ReadU16(uint32 address)
{
if(MAS_NATIVE_IS_BIGENDIAN == big_endian)
return *(uint16*)(((uint8*)data16) + address);
else
return LoadU16_RBO((uint16*)(((uint8*)data16) + address));
}
INLINE uint32 ReadU32(uint32 address)
{
if(MAS_NATIVE_IS_BIGENDIAN == big_endian)
return *(uint32*)(((uint8*)data32) + address);
else
return LoadU32_RBO((uint32*)(((uint8*)data32) + address));
}
INLINE uint32 ReadU24(uint32 address)
{
uint32 ret;
if(!big_endian)
{
ret = ReadU8(address) | (ReadU8(address + 1) << 8) | (ReadU8(address + 2) << 16);
}
return(ret);
}
INLINE void WriteU8(uint32 address, uint8 value)
{
data8[address] = value;
}
INLINE void WriteU16(uint32 address, uint16 value)
{
if(MAS_NATIVE_IS_BIGENDIAN == big_endian)
*(uint16*)(((uint8*)data16) + address) = value;
else
StoreU16_RBO((uint16*)(((uint8*)data16) + address), value);
}
INLINE void WriteU32(uint32 address, uint32 value)
{
if(MAS_NATIVE_IS_BIGENDIAN == big_endian)
*(uint32*)(((uint8*)data32) + address) = value;
else
StoreU32_RBO((uint32*)(((uint8*)data32) + address), value);
}
INLINE void WriteU24(uint32 address, uint32 value)
{
if(!big_endian)
{
WriteU8(address + 0, value >> 0);
WriteU8(address + 1, value >> 8);
WriteU8(address + 2, value >> 16);
}
}
template<typename T>
INLINE T Read(uint32 address)
{
if(sizeof(T) == 4)
return(ReadU32(address));
else if(sizeof(T) == 2)
return(ReadU16(address));
else
return(ReadU8(address));
}
template<typename T>
INLINE void Write(uint32 address, T value)
{
if(sizeof(T) == 4)
WriteU32(address, value);
else if(sizeof(T) == 2)
WriteU16(address, value);
else
WriteU8(address, value);
}
};
#undef MAS_NATIVE_IS_BIGENDIAN
#endif