MPYSP2DP Multiply Two Single-Precision Floating-Point Values for Double-Precision Result (C67x+ CPU)

 

 

Multiply Two Single-Precision Floating-Point Values for

 

 

 

 

 

 

MPYSP2DP

 

 

 

 

 

 

 

 

 

 

 

Double-Precision Result

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Syntax

 

 

 

 

MPYSP2DP (.unit) src1, src2, dst

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

.unit = .M1 or .M2

 

 

 

 

 

 

 

 

 

 

 

 

 

Compatibility

 

 

C67x+ CPU only

 

 

 

 

 

 

 

 

 

 

 

 

 

Opcode

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

31

29

28

27

23

22

18

17

13

12

11

7

6

5

4

3

2

1

0

creg

z

dst

src2

src1

x

0

1

0

1

1

1

1

 

 

 

 

 

 

 

1 0 0 s

p

3 155511 1

Opcode map field used...

For operand type...

Unit

 

 

 

src1

sp

.M1, .M2

src2

xsp

 

dst

sp

 

 

 

 

Description

The src1 operand is multiplied by the src2 operand to produce a

 

double-precision result. The result is placed in dst.

Execution

if (cond)

src1 ￿ src2 dst

 

else

nop

Notes:

1)If one source is SNaN or QNaN, the result is a signed NaN_out. If either source is SNaN, the INVAL bit is set also. The sign of NaN_out is the exclusive-OR of the input signs.

2)Signed infinity multiplied by signed infinity or a normalized number (other than signed 0) returns signed infinity. Signed infinity multiplied by signed 0 returns a signed NaN_out and sets the INVAL bit.

3)If one or both sources are signed 0, the result is signed 0 unless the other source is NaN or signed infinity, in which case the result is signed NaN_out.

4)A denormalized source is treated as signed 0 and the DENn bit is set. The INEX bit is set except when the other source is signed infinity, signed NaN, or signed 0. Therefore, a signed infinity multiplied by a denormal- ized number gives a signed NaN_out and sets the INVAL bit.

5)If rounding is performed, the INEX bit is set.

3-170

Instruction Set

SPRU733

Page 230
Image 230
Texas Instruments TMS320C67X/C67X+ DSP manual Multiply Two Single-Precision Floating-Point Values for, MPYSP2DP