Texas Instruments TMS320C67X/C67X+ DSP manual Rsqrsp .S1

RSQRSP Single-Precision Floating-Point Square-Root Reciprocal Approximation

Note:

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 calculate 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
		Pipeline		E1
		Stage
		Read		src2
		Written		dst
		Unit in use			.S
Instruction Type	Single-cycle
Delay Slots	0
Functional Unit	1
Latency
See Also	RCPSP, RSQRDP
Example 1	RSQRSP .S1			A1,A2
			Before instruction
		A1	4080 0000h			4.0	A1
		A2	xxxx xxxxh				A2
Example 2
	RSQRSP .S2X A1,B2
			Before instruction
		A1	4109 999Ah			8.6	A1
		B2	xxxx xxxxh				B2

1 cycle after instruction

4080 0000h 4.0

3F00 0000h 0.5

1 cycle after instruction

4109	999Ah	8.6
3EAE	8000h	0.34082031

3-204 Instruction Set SPRU733