s32 a = -((s32)(reg[0].I * reg[0].I)) >> 14;
s32 a =  -(((s32)(reg[0].I*reg[0].I)) >> 14);
void BIOS_ArcTan(){#ifdef DEV_VERSION  if(systemVerbose & VERBOSE_SWI) {    log("ArcTan: %08x (VCOUNT=%2d)\n",        reg[0].I,        VCOUNT);  }#endif  s32 a = -((s32)(reg[0].I * reg[0].I)) >> 14;   s32 b = ((0xA9 * a) >> 14) + 0x390;  b = ((b * a) >> 14) + 0x91C;  b = ((b * a) >> 14) + 0xFB6;  b = ((b * a) >> 14) + 0x16AA;  b = ((b * a) >> 14) + 0x2081;  b = ((b * a) >> 14) + 0x3651;  b = ((b * a) >> 14) + 0xA2F9;  reg[0].I = (reg[0].I * b) >> 16;#ifdef DEV_VERSION  if(systemVerbose & VERBOSE_SWI) {    log("ArcTan: return=%08x\n",        reg[0].I);  }#endif}