openpower/isa/bcd.mdwn

   1 # Convert Declets To Binary Coded Decimal
   2
   3 * cdtbcd RA, RS
   4
   5     do i = 0 to 1
   6       n <- i * 32
   7       RA[n+0:n+7] <- 0
   8       RA[n+8:n+19 ] <- DPD_TO_BCD( (RS)[n+12:n+21] )
   9       RA[n+20:n+31] <- DPD_TO_BCD( (RS)[n+22:n+31] )
  10
  11 # Add and Generate Sixes
  12
  13 * addg6s RT,RA,RB
  14
  15     do i = 0 to 15
  16         dci <- carry_out(RA[4xi:63] + RB[4xi:63])
  17         c <- [dc[0]]*4 || [dc[1]]*4 || ... || [dc[15]]*4
  18         RT <- (¬c) & 0x6666_6666_6666_6666
  19
  20 # Convert Binary Coded Decimal To Declets
  21
  22 * cbcdtd RA, RS
  23
  24     do i = 0 to 1
  25       n <- i * 32
  26       RA[n+0:n+11] <- 0
  27       RA[n+12:n+21] <- BCD_TO_DPD( (RS)[n+8:n+19] )
  28       RA[n+22:n+31] <- BCD_TO_DPD( (RS)[n+20:n+31] )