Esempio n. 1
0
// Update cr0 with value
static void
updateConditionRegister(PPCEmuAssembler& a, const asmjit::X86GpReg& value, const asmjit::X86GpReg& tmp, const asmjit::X86GpReg& tmp2)
{
   auto crtarget = 0;
   auto crshift = (7 - crtarget) * 4;

   a.mov(tmp, a.ppccr);
   a.and_(tmp, ~(0xF << crshift));

   a.cmp(value, 0);

   a.lahf();
   a.mov(tmp2, 0);
   a.sete(tmp2.r8());
   a.shl(tmp2, crshift + ConditionRegisterFlag::ZeroShift);
   a.or_(tmp, tmp2);

   a.sahf();
   a.mov(tmp2, 0);
   a.setg(tmp2.r8());
   a.shl(tmp2, crshift + ConditionRegisterFlag::PositiveShift);
   a.or_(tmp, tmp2);

   a.sahf();
   a.mov(tmp2, 0);
   a.setl(tmp2.r8());
   a.shl(tmp2, crshift + ConditionRegisterFlag::NegativeShift);
   a.or_(tmp, tmp2);

   a.mov(tmp2, a.ppcxer);
   a.and_(tmp2, XERegisterBits::StickyOV);
   a.shiftTo(tmp2, XERegisterBits::StickyOVShift, crshift + ConditionRegisterFlag::SummaryOverflowShift);
   a.or_(tmp, tmp2);

   a.mov(a.ppccr, tmp);
}
Esempio n. 2
0
static bool
cmpGeneric(PPCEmuAssembler& a, Instruction instr)
{
   uint32_t crshift = (7 - instr.crfD) * 4;

   // Load CRF
   a.mov(a.edx, a.ppccr);
   
   // Mask CRF
   uint32_t mask = 0xFFFFFFFF;
   mask &= ~(0xF << crshift);
   a.and_(a.edx, mask);

   // Summary Overflow
   a.mov(a.eax, a.ppcxer);
   a.and_(a.eax, XERegisterBits::StickyOV);
   a.shr(a.eax, XERegisterBits::StickyOVShift);
   a.shl(a.eax, ConditionRegisterFlag::SummaryOverflowShift << crshift);
   a.or_(a.edx, a.eax);

   // Perform Comparison
   a.mov(a.eax, a.ppcgpr[instr.rA]);

   if (flags & CmpImmediate) {
      if (std::is_signed<Type>::value) {
         a.mov(a.ecx, sign_extend<16>(instr.simm));
      } else {
         a.mov(a.ecx, instr.uimm);
      }
   } else {
      a.mov(a.ecx, a.ppcgpr[instr.rB]);
   }

   a.cmp(a.eax, a.ecx);
   a.mov(a.r8d, 0);
   if (std::is_unsigned<Type>::value) {
      a.seta(a.r8d.r8());
   } else {
      a.setg(a.r8d.r8());
   }
   a.mov(a.r9d, 0);
   if (std::is_unsigned<Type>::value) {
      a.setb(a.r9d.r8());
   } else {
      a.setl(a.r9d.r8());
   }

   a.mov(a.ecx, 0);
   a.sete(a.ecx.r8());
   a.shl(a.ecx, crshift + ConditionRegisterFlag::ZeroShift);
   a.or_(a.edx, a.ecx);

   a.mov(a.ecx, a.r8d);
   a.shl(a.ecx, crshift + ConditionRegisterFlag::PositiveShift);
   a.or_(a.edx, a.ecx);
   
   a.mov(a.ecx, a.r9d);
   a.shl(a.ecx, crshift + ConditionRegisterFlag::NegativeShift);
   a.or_(a.edx, a.ecx);

   a.mov(a.ppccr, a.edx);

   return true;
}