//stores generic information about all decoded arm instructions
//decodes bits 27-26 and returns specified instruction type
public static Instructions decode(uint instruction, Registers myRegisters, Memory myMemory, bool disassembling)
{
// check opcodes here
dontDoItBro = false;
firstOpcode = passOpcode(getSectionValue(31, 28, instruction), myMemory);
if (firstOpcode == null)
{
dontDoItBro = true;
return null;
//get outta here. this instructions a bad one
}
//handle specials here
In_Special sInstruction = new In_Special(myRegisters, myMemory, instruction, disassembling);
if (sInstruction.isSpecial())
{
return sInstruction;
}
if (getSectionValue(27, 20, instruction) == 18 && getSectionValue(7, 4, instruction) == 1)
{
return new In_Branch(myRegisters, myMemory, instruction, disassembling);
}
else
{
//previously checked only bits 27, - 26
uint type = getSectionValue(27, 25, instruction);
if (type == 0 || type == 1)
{
return new In_DataProcessing(myRegisters, myMemory, instruction, disassembling);
}
if (type == 2 || type == 3 || type == 4)
{
return new In_LoadStore(myRegisters, myMemory, instruction, disassembling);
}
else
{
return new In_Branch(myRegisters, myMemory, instruction, disassembling);
}
}
}
//stores generic information about all decoded arm instructions
//decodes bits 27-26 and returns specified instruction type
public static Instructions decode(uint instruction, Registers myRegisters, Memory myMemory, bool disassembling)
{
// check opcodes here
dontDoItBro = false;
firstOpcode = passOpcode(getSectionValue(31, 28, instruction), myMemory);
if (firstOpcode == null)
{
dontDoItBro = true;
return(null);
//get outta here. this instructions a bad one
}
//handle specials here
In_Special sInstruction = new In_Special(myRegisters, myMemory, instruction, disassembling);
if (sInstruction.isSpecial())
{
return(sInstruction);
}
if (getSectionValue(27, 20, instruction) == 18 && getSectionValue(7, 4, instruction) == 1)
{
return(new In_Branch(myRegisters, myMemory, instruction, disassembling));
}
else
{
//previously checked only bits 27, - 26
uint type = getSectionValue(27, 25, instruction);
if (type == 0 || type == 1)
{
return(new In_DataProcessing(myRegisters, myMemory, instruction, disassembling));
}
if (type == 2 || type == 3 || type == 4)
{
return(new In_LoadStore(myRegisters, myMemory, instruction, disassembling));
}
else
{
return(new In_Branch(myRegisters, myMemory, instruction, disassembling));
}
}
}