Example #1
0
static bool
fmaddGeneric(PPCEmuAssembler& a, Instruction instr)
{
   if (instr.rc) {
      return jit_fallback(a, instr);
   }

   // FPSCR, FPRF supposed to be updated here...

   auto result = a.allocXmmTmp();
   {
      auto srcC = a.loadRegisterRead(a.fprps[instr.frC]);
      // Do the rounding first so we don't run out of host registers
      if (ShouldRound) {
         auto tmpSrcC = a.allocXmmTmp(srcC);
         roundTo24BitSd(a, tmpSrcC);
         srcC = tmpSrcC;
      }
      auto srcA = a.loadRegisterRead(a.fprps[instr.frA]);
      auto srcB = a.loadRegisterRead(a.fprps[instr.frB]);

      a.movq(result, srcA);
      if (hostHasFMA3()) {
         if (ShouldSubtract) {
            a.vfmsub132sd(result, srcB, srcC);
         } else {
            a.vfmadd132sd(result, srcB, srcC);
         }
      } else {  // no FMA3
         a.mulsd(result, srcC);
         if (ShouldSubtract) {
            a.subsd(result, srcB);
         } else {
            a.addsd(result, srcB);
         }
      }
   }

   if (ShouldNegate) {
      negateXmmSd(a, result);
   }

   if (ShouldRound) {
      roundToSingleSd(a, result, result);
      auto dst = a.loadRegisterWrite(a.fprps[instr.frD]);
      a.movddup(dst, result);
   } else {
      auto dst = a.loadRegisterReadWrite(a.fprps[instr.frD]);
      a.movsd(dst, result);
   }

   return true;
}