ADD2 Add Two 16-Bit Integers on Upper and Lower Register Halves

Execution

if (cond)

{

 

 

 

 

msb16(src1) + msb16(src2) msb16(dst);

 

 

 

lsb16(src1) + lsb16(src2) lsb16(dst);

 

 

 

}

 

 

else nop

 

 

Pipeline

 

 

 

 

 

Pipeline

E1

 

 

 

 

 

 

Stage

 

 

 

 

 

 

 

 

Read

src1, src2

 

 

 

Written

dst

 

 

 

Unit in use

.S

 

 

 

 

 

 

Instruction Type

Single-cycle

 

 

Delay Slots

0

 

 

See Also

ADD, ADDU, SUB2

 

Example

ADD2 .S1X

A1,B1,A2

 

 

 

Before instruction

1 cycle after instruction

A1

A2

B1

0021 37E1h

xxxxxxxxh

039A E4B8h

33 14305

A1

 

A2

922 58552

B1

0021 37E1h

03BB 1C99h

039A E4B8h

955 7321

3-66

Instruction Set

SPRU733

Page 126
Image 126
Texas Instruments TMS320C67X/C67X+ DSP manual ADD, ADDU, SUB2, Pipeline Stage Read