Single-Precision Floating-Point Square-Root Reciprocal Approximation
RSQRSP
4-69
TMS320C67x Floating-Point Instruction Set
Notes:
1) If
src2 is SNaN, NaN_out is placed in dst and the INVAL and NAN2 bits
are set.
2) If
src2 is QNaN, NaN_out is placed in dst and the NAN2 bit is set.
3) If
src2 is a negative, nonzero, nondenormalized number, NaN_out is
placed in
dst and the INVAL bit is set.
4) If
src2 is a signed denormalized number, signed infinity is placed in dst
and the DIV0, INEX, and DEN2 bits are set.
5) If
src2 is signed 0, signed infinity is placed in dst and the DIV0 and INFO
bits are set. The Newton-Rhapson approximation cannot be used to cal-
culate the square root of 0 because infinity multiplied by 0 is invalid.
6) If
src2 is positive infinity, positive 0 is placed in dst.
Pipeline
Stage
E1
Read
src2
Written
dst
Unit in use
.S
Instruction Type
Single-cycle
Delay Slots
0
Functional Unit
Latency
1
Example 1
RSQRSP .S1 A1,A2
Before instruction
1 cycle after instruction
A1
4080 0000h
4.0
A1
4080 0000h
4.0
A2
XXXX XXXXh
A2
3F00 0000h
0.5
Pipeline