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Cleaned up some code in Thumb ARM emulator, and clearly marked compiler 

warnings that should eventually be fixed.


git-svn-id: svn://svn.code.sf.net/p/stella/code/trunk@3193 8b62c5a3-ac7e-4cc8-8f21-d9a121418aba
This commit is contained in:
stephena 2015-08-09 21:19:10 +00:00
parent 3312ea5b70
commit 74b2a209e2
1 changed files with 23 additions and 31 deletions
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54
src/emucore/Thumbulator.cxx
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@ -47,6 +47,14 @@ using namespace Common;
#define DO_DBUG(statement)
#endif
#ifdef __BIG_ENDIAN__
#define CONV_DATA(d) (((d & 0xFFFF)>>8) | ((d & 0xffff)<<8)) & 0xffff;
#define CONV_RAMROM(d) ((d>>8) | (d<<8)) & 0xffff;
#else
#define CONV_DATA(d) (d & 0xFFFF);
#define CONV_RAMROM(d) (d);
#endif
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Thumbulator::Thumbulator(const uInt16* rom_ptr, uInt16* ram_ptr, bool traponfatal)
: rom(rom_ptr),
@ -140,22 +148,14 @@ uInt32 Thumbulator::fetch16 ( uInt32 addr )
fatalError("fetch16", addr, "abort");
addr>>=1;
#ifdef __BIG_ENDIAN__
data=((rom[addr]>>8)|(rom[addr]<<8))&0xffff;
#else
data=rom[addr];
#endif
data=CONV_RAMROM(rom[addr]);
DO_DBUG(statusMsg << "fetch16(" << Base::HEX8 << addr << ")=" << Base::HEX4 << data << endl);
return(data);
case 0x40000000: //RAM
addr &= RAMADDMASK;
addr>>=1;
#ifdef __BIG_ENDIAN__
data=((ram[addr]>>8)|(ram[addr]<<8))&0xffff;
#else
data=ram[addr];
#endif
data=CONV_RAMROM(ram[addr]);
DO_DBUG(statusMsg << "fetch16(" << Base::HEX8 << addr << ")=" << Base::HEX4 << data << endl);
return(data);
}
@ -209,11 +209,7 @@ void Thumbulator::write16 ( uInt32 addr, uInt32 data )
case 0x40000000: //RAM
addr&=RAMADDMASK;
addr>>=1;
#ifdef __BIG_ENDIAN__
ram[addr]=(((data&0xFFFF)>>8)|((data&0xffff)<<8))&0xffff;
#else
ram[addr]=data&0xFFFF;
#endif
ram[addr]=CONV_DATA(data);
return;
case 0xE0000000: //MAMCR
@ -282,22 +278,14 @@ uInt32 Thumbulator::read16 ( uInt32 addr )
case 0x00000000: //ROM
addr&=ROMADDMASK;
addr>>=1;
#ifdef __BIG_ENDIAN__
data=((rom[addr]>>8)|(rom[addr]<<8))&0xffff;
#else
data=rom[addr];
#endif
data=CONV_RAMROM(rom[addr]);
DO_DBUG(statusMsg << "read16(" << Base::HEX8 << addr << ")=" << Base::HEX4 << data << endl);
return(data);
case 0x40000000: //RAM
addr&=RAMADDMASK;
addr>>=1;
#ifdef __BIG_ENDIAN__
data=((ram[addr]>>8)|(ram[addr]<<8))&0xffff;
#else
data=ram[addr];
#endif
data=CONV_RAMROM(ram[addr]);
DO_DBUG(statusMsg << "read16(" << Base::HEX8 << addr << ")=" << Base::HEX4 << data << endl);
return(data);
@ -689,7 +677,7 @@ int Thumbulator::execute ( void )
{
rb=(inst>>0)&0xFF;
if(rb&0x80)
rb|=(~0)<<8;
rb|=(~0)<<8; // FIXME - shifting a negative signed value is undefined
op=(inst>>8)&0xF;
rb<<=1;
rb+=pc;
@ -837,7 +825,7 @@ int Thumbulator::execute ( void )
{
rb=(inst>>0)&0x7FF;
if(rb&(1<<10))
rb|=(~0)<<11;
rb|=(~0)<<11; // FIXME - shifting a negative signed value is undefined
rb<<=1;
rb+=pc;
rb+=2;
@ -1233,7 +1221,8 @@ int Thumbulator::execute ( void )
{
}
rc&=0xFF;
if(rc&0x80) rc|=((~0)<<8);
if(rc&0x80)
rc|=((~0)<<8); // FIXME - shifting a negative signed value is undefined
write_register(rd,rc);
return(0);
}
@ -1248,7 +1237,8 @@ int Thumbulator::execute ( void )
rb=read_register(rn)+read_register(rm);
rc=read16(rb);
rc&=0xFFFF;
if(rc&0x8000) rc|=((~0)<<16);
if(rc&0x8000)
rc|=((~0)<<16); // FIXME - shifting a negative signed value is undefined
write_register(rd,rc);
return(0);
}
@ -1893,7 +1883,8 @@ int Thumbulator::execute ( void )
DO_DISS(statusMsg << "sxtb r" << dec << rd << ",r" << dec << rm << endl);
ra=read_register(rm);
rc=ra&0xFF;
if(rc&0x80) rc|=(~0)<<8;
if(rc&0x80)
rc|=(~0)<<8; // FIXME - shifting a negative signed value is undefined
write_register(rd,rc);
return(0);
}
@ -1906,7 +1897,8 @@ int Thumbulator::execute ( void )
DO_DISS(statusMsg << "sxth r" << dec << rd << ",r" << dec << rm << endl);
ra=read_register(rm);
rc=ra&0xFFFF;
if(rc&0x8000) rc|=(~0)<<16;
if(rc&0x8000)
rc|=(~0)<<16; // FIXME - shifting a negative signed value is undefined
write_register(rd,rc);
return(0);
}