openpower/isa/simplev.mdwn

   1 <!-- This defines instructions described in PowerISA Version 3.0 B Book 1 -->
   2
   3 <!-- These are not described in book 1 -->
   4
   5 # setvl
   6
   7 SVL-Form
   8
   9 * setvl RT, RA, SVi, vf, vs, ms
  10 * setvl. RT, RA, SVi, vf, vs, ms
  11
  12 Pseudo-code:
  13
  14     if (vf & (¬vs) & ¬(ms)) = 1 then
  15         SVSTATE_NEXT
  16     else
  17         VLimm <- SVi + 1
  18         if vs = 1 then
  19             if _RA != 0 then
  20                 VL <- (RA|0)[57:63]
  21             else
  22                 VL <- VLimm[0:6]
  23         else
  24             VL <- SVSTATE[7:13]
  25         if ms = 1 then
  26             MVL <- VLimm[0:6]
  27         else
  28             MVL <- SVSTATE[0:6]
  29         if VL > MVL then
  30             VL = MVL
  31         SVSTATE[0:6] <- MVL
  32         SVSTATE[7:13] <- VL
  33         if _RT != 0b00000 then
  34             GPR(_RT) <- [0]*57 || VL
  35         MSR[6] <- vf
  36
  37 Special Registers Altered:
  38
  39     CR0                     (if Rc=1)
  40
  41 # svremap
  42
  43 SVM-Form
  44
  45 * svremap SVxd, SVyd, SVzd, SVRM
  46
  47 Pseudo-code:
  48
  49     # clear out all SVSHAPEs
  50     SVSHAPE0[0:31] <- [0] * 32
  51     SVSHAPE1[0:31] <- [0] * 32
  52     SVSHAPE2[0:31] <- [0] * 32
  53     SVSHAPE3[0:31] <- [0] * 32
  54     # set schedule up for multiply
  55     if (SVRM = 0b00000) then
  56         # set up template in SVSHAPE0, then copy to 1-3
  57         SVSHAPE0[0:5] <- (0b0 || SVxd)   # xdim
  58         SVSHAPE0[6:11] <- (0b0 || SVyd)   # ydim
  59         SVSHAPE0[12:17] <- (0b0 || SVzd)   # zdim
  60         SVSHAPE0[28:29] <- 0b11           # skip z
  61         # copy
  62         SVSHAPE1[0:31] <- SVSHAPE0[0:31]
  63         SVSHAPE2[0:31] <- SVSHAPE0[0:31]
  64         SVSHAPE3[0:31] <- SVSHAPE0[0:31]
  65         # set up FRA
  66         SVSHAPE1[18:20] <- 0b001          # permute x,z,y
  67         SVSHAPE1[28:29] <- 0b01           # skip z
  68         # FRC
  69         SVSHAPE2[18:20] <- 0b001          # permute x,z,y
  70         SVSHAPE2[28:29] <- 0b11           # skip y
  71     # set schedule up for butterfly
  72     if (SVRM = 0b00001) then
  73         # set up template in SVSHAPE0, then copy to 1-3
  74         # for FRA and FRT
  75         SVSHAPE0[0:5] <- (0b0 || SVxd)   # xdim
  76         SVSHAPE0[30:31] <- 0b01          # Butterfly mode
  77         # copy
  78         SVSHAPE1[0:31] <- SVSHAPE0[0:31]
  79         SVSHAPE2[0:31] <- SVSHAPE0[0:31]
  80         # set up FRB and FRS
  81         SVSHAPE1[28:29] <- 0b01           # j+halfstep schedule
  82         # FRC (coefficients)
  83         SVSHAPE2[28:29] <- 0b10           # k schedule
  84
  85 Special Registers Altered:
  86
  87     None
  88