Encoding:

Format:

ADDS_A.df 

ADDS_A.B wd,ws,wt

ADDS_A.H wd,ws,wt

ADDS_A.W wd,ws,wt

ADDS_A.D wd,ws,wt

Purpose:

Vector Saturated Add of Absolute Values

Vector saturated addition to vector of absolute values.

Description:

wd[i] = saturate_signed(absolute_value(ws[i]) + absolute_value(wt[i]))

The absolute values of the elements in v ector wt are added to the absolute values of the elements in v ector ws. The saturated signed result is written to vector wd.

The operands and results are values in integer data format df.

Restrictions:

No data-dependent exceptions are possible.

Operation:

ADDS_A.B:
   for i in 0 .. WRLEN/8-1
      WR[wd]8i+7..8i = adds_a(WR[ws]8i+7..8i, WR[wt]8i+7..8i, 8)
   endfor
ADDS_A.H:
   for i in 0 .. WRLEN/16-1
      WR[wd]16i+15..16i = adds_a(WR[ws]16i+15..16i, WR[wt]16i+15..16i, 16)
   endfor
ADDS_A.W:
   for i in 0 .. WRLEN/32-1
      WR[wd]32i+31..32i = adds_a(WR[ws]32i+31..32i, WR[wt]32i+31..32i, 32)
   endfor
ADDS_A.D:
   for i in 0 .. WRLEN/64-1
      WR[wd]64i+63..64i = adds_a(WR[ws]64i+63..64i, WR[wt]64i+63..64i, 64)
   endfor
function abs(tt, n)
   if ttn-1 = 1 then
      return -ttn-1...0
   else
      return ttn-1..0
   endif
endfunction abs
function sat_s(tt, n, b)
   if ttn-1 = 0 and ttn-1..b-1 != 0n-b+1 then
      return 0n-b+1 || 1b-1
   endif
   if ttn-1 = 1 and ttn-1..b-1 != 1n-b+1 then
      return 1n-b+1 || 0b-1
   else
      return tt
   endif
endfunction sat_s
function adds_a(ts, tt, n)
   t = (0 || abs(ts, n)) + (0 || abs(tt, n))
   return sat_s(t, n+1, n)
endfunction adds_a

Exceptions:

Reserved Instruction Exception, MSA Disabled Exception.