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Arithmetic shift right shr – Texas Instruments TMS320C67X/C67X+ DSP User Manual

Page 275

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Arithmetic Shift Right

SHR

3-215

Instruction Set

SPRU733

Arithmetic Shift Right

SHR

Syntax

SHR (.unit) src2, src1, dst

.unit = .S1 or .S2

Compatibility

C62x, C64x, C67x, and C67x+ CPU

Opcode

31

29

28

27

23

22

18

17

13

12

11

6

5

4

3

2

1

0

creg

z

dst

src2

src1

x

op

1 0 0 0 s p

3

1

5

5

5

1

6

1

1

Opcode map field used...

For operand type...

Unit

Opfield

src2
src1
dst

xsint
uint
sint

.S1, .S2

11 0111

src2
src1
dst

slong
uint
slong

.S1, .S2

11 0101

src2
src1
dst

xsint
ucst5
sint

.S1, .S2

11 0110

src2
src1
dst

slong
ucst5
slong

.S1, .S2

11 0100

Description

The src2 operand is shifted to the right by the src1 operand. The sign-extended
result is placed in dst. When a register is used, the six LSBs specify the shift
amount and valid values are 0−40. When an immediate value is used, valid
shift amounts are 0–31.

If 39

<

src1

<

64, src2 is shifted to the right by 40. Only the six LSBs of src1 are

used by the shifter, so any bits set above bit 5 do not affect execution.

Execution

if (cond)

src2

>>

s src1

dst

else nop