PNX1300 Philips, PNX1300 Datasheet - Page 376

• Manufacturer Part Number: PNX1300
• Description: Media Processors
• Manufacturer: Philips

Philips Semiconductors
Signed select byte
SYNTAX
FUNCTION
DESCRIPTION
bits, and stores the result in rdest. The value of rsrc2 determines which byte is selected, with rsrc2=0 selecting the
LSB of rsrc1 and rsrc2=3 selecting the MSB of rsrc1. If rsrc2 is not between 0 and 3 inclusive, the result of
ibytesel
modification of the destination register. If the LSB of rguard is 1, rdest is written; otherwise, rdest is not changed.
EXAMPLES
r30 = 0x44332211, r40 = 1
r10 = 0, r60 = 0xddccbbaa, r70 = 2
r20 = 1, r60 = 0xddccbbaa, r70 = 2
r100 = 0xffffff7f, r110 = 0
As shown below, the
The
[ IF rguard ] ibytesel rsrc1 rsrc2
if rguard then {
}
rsrc1
if rsrc2 = 0 then
else if rsrc2 = 1 then
else if rsrc2 = 2 then
else if rsrc2 = 3 then
ibytesel
31
rdest
rdest
rdest
rdest
signed
Initial Values
is undefined.
sign_ext8to32(rsrc1<7:0>)
sign_ext8to32(rsrc1<15:8>)
sign_ext8to32(rsrc1<23:16>)
sign_ext8to32(rsrc1<31:24>)
23
operation optionally takes a guard, specified in rguard. If a guard is present, its LSB controls the
3
signed
ibytesel
2
15
1
rdest
signed
operation selects one byte from the argument, rsrc1, sign-extends the byte to 32
ibytesel r30 r40
IF r10 ibytesel r60 r70
IF r20 ibytesel r60 r70
ibytesel r100 r110
31
S
0
S
S
7
S
S
signed
S
S
S
S
S
0
S
S
Operation
rdest
S
S
S
S
S
S
PRELIMINARY SPECIFICATION
rsrc2
S
r50
S
S
31
r120
S
S
S
PNX1300/01/02/11 DSPCPU Operations
S
S
7
7
r80
r90
signed
signed
r50
no change, since guard is false
r90
r120
0
0
Function unit
Operation code
Number of operands
Modifier
Modifier range
Latency
Issue slots
ubytesel sex8 packbytes
0x00000022
0xffffffcc
0x0000007f
ATTRIBUTES
SEE ALSO
Result
ibytesel
1, 2, 3, 4, 5
1
alu
No
56
—
0
2
1
A-78