Encoding:

POOL32A

000000

rt

rs

BITREV

0011000100

POOL32Axf

111100

6

5

5

10

6

SPECIAL3

011111

0

rt

rd

BITREV

11011

ABSQ_S.PH

010010

6

5

5

5

5

6

Format: 

BITREV rdt, rts

microMIPSDSP

Bit-Reverse Halfword

Purpose:

Bit-Reverse Halfword

To reverse the order of the bits of the least-significant halfword in the specified register.

Description: 

rdt = zero_extend(rts0..15)

The right-most halfword value in register rts is bit-reversed into the right-most halfword position in the destination register rdt. The 48 most-significant bits of the destination register are zero-filled.

Restrictions:

No data-dependent exceptions are possible.

The operands must be values in the specified format. If they are not, the results are UNPREDICTABLE and the values of the operand vectors become UNPREDICTABLE.

Operation: 

temp15..0 = GPR[rts]0..15
GPR[rdt]63..0 = 048 || temp15..0

Exceptions:

Reserved Instruction, DSP Disabled