//64bit multiply instructions (SMULL/UMULL/SMLAL/UMLAL)
internal uint ExecuteDataOpMultiplyLong(DataOpMultiplyLongRaw opHandler, uint opcode, bool setflags)
{
//See comment in ExecuteDataOpMultiply
uint Rm = (opcode) & 0xf;
uint Rs = (opcode >> 8) & 0xf;
uint RdHi = (opcode >> 16) & 0xf;
uint RdLo = (opcode >> 12) & 0xf;
uint rs_value = get_reg(Rs);
uint rm_value = get_reg(Rm);
UInt64 rdhilo_value = (((UInt64)get_reg(RdHi)) << 32) | (UInt64)get_reg(RdLo);
//The number of cycles taken for multiplication varies depending
//on the magnitude of rs_value.
uint M = calculateMultM(rs_value);
LongMultiplyOpResult result = opHandler(rdhilo_value, rs_value, rm_value);
mGPR[RdHi] = (UInt32)((result.output_value >> 32) & 0xffffffff);
mGPR[RdLo] = (UInt32)((result.output_value) & 0xffffffff);
//If we set the flags after a long multiply, the N flag is based on bit 63, not bit 31.
if (setflags)
{
CPSR.set_NZCV((result.output_value & 0x8000000000000000) != 0, result.output_value == 0, CPSR.cf, CPSR.vf);
}
return(result.cycles + M);
}
} //calculateMultM
//32bit multiply instructions (MUL/MLA)
internal uint ExecuteDataOpMultiply(DataOpMultiplyRaw opHandler, uint opcode, bool setflags)
{
//The original code used the masks rd_mask, rn_mask, rm_mask and rs_mask here
//But the operands are in a strange order so the masks were used in a confusing way.
//Therefore, we have one of the rare cases where it's better to use magic numbers...
uint Rm = (opcode) & 0xf;
uint Rs = (opcode >> 8) & 0xf;
uint Rd = (opcode >> 16) & 0xf;
uint Rn = (opcode >> 12) & 0xf;
uint rs_value = get_reg(Rs);
uint rm_value = get_reg(Rm);
uint rn_value = get_reg(Rn);
//The number of cycles taken for multiplication varies depending
//on the magnitude of rs_value.
uint M = calculateMultM(rs_value);
MultiplyOpResult result = opHandler(rn_value, rs_value, rm_value);
mGPR[Rd] = result.output_value;
if (setflags)
{
CPSR.set_NZCV((result.output_value & 0x80000000) != 0, result.output_value == 0, CPSR.cf, CPSR.vf);
}
return(M + result.cycles);
}
internal void DataOpHandleSetFlagsAWC_CMP(uint opcode, uint Rd, AWCResult awcResult)
{
//The CPSR is set the same way for all AWC-based instructions (the only difference
//is the input to AWC).
CPSR.set_NZCV((awcResult.result & 0x80000000) != 0, awcResult.result == 0, awcResult.carry_out, awcResult.overflow);
}
internal void DataOpHandleSetFlagsLogical_CMP(uint opcode, uint Rd, uint result, bool shift_carry)
{
//The CPSR is always set the same way for logical operations
//cf. MOV (ARMv7 A8.8.102)
CPSR.set_NZCV((result & 0x80000000) != 0, result == 0, shift_carry, CPSR.vf);
}