tm1300 NXP Semiconductors, tm1300 Datasheet - Page 423

• Manufacturer Part Number: tm1300
• Description: Tm-1300 Media Processor
• Manufacturer: NXP Semiconductors

Philips Semiconductors
Merge least-significant byte
SYNTAX
FUNCTION
DESCRIPTION
r src1 and r src2 into r dest . The least-significant byte from r src2 is packed into the least-significant byte of r dest ; the
least-significant byte from r src1 is packed into the second-least-significant byte of r dest ; the second-least-significant
byte from r src2 is packed into the second-most-significant byte of r dest ; and the second-least-significant byte from
r src1 is packed into the most-significant byte of r dest .
modification of the destination register. If the LSB of r guard is 1, r dest is written; otherwise, r dest is unchanged.
EXAMPLES
r30 = 0x12345678, r40 = 0xaabbccdd
r10 = 0, r40 = 0xaabbccdd, r30 = 0x12345678
r20 = 1, r40 = 0xaabbccdd, r30 = 0x12345678
As shown below, the
The
[ IF r guard ] mergelsb r src1 r src2
if r guard then {
}
r src1
mergelsb
r dest <7:0>
r dest <15:8>
r dest <23:16>
r dest <31:24>
3
Initial Values
2
r src2 <7:0>
operation optionally takes a guard, specified in r guard . If a guard is present, its LSB controls the
r src1 <7:0>
r src2 <15:8>
r src1 <15:8>
mergelsb
1
r dest
operation interleaves the two pairs of least-significant bytes from the arguments
3
7
mergelsb r30 r40
IF r10 mergelsb r40 r30
IF r20 mergelsb r40 r30
2
0
r dest
1
Operation
PRODUCT SPECIFICATION
r src2
3
7
r50
2
DSPCPU Operations for TM1300
r60
r70
0
Function unit
Operation code
Number of operands
Modifier
Modifier range
Latency
Issue slots
pack16lsb pack16msb
packbytes mergemsb
r50
no change, since guard is false
r70
1
ATTRIBUTES
0x56cc78dd
0xcc56dd78
SEE ALSO
mergelsb
Result
7
1, 2, 3, 4, 5
alu
No
57
—
0
2
1
A-137