PNX1300 Philips, PNX1300 Datasheet - Page 390

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

Philips Semiconductors
Convert signed integer to floating-point
SYNTAX
FUNCTION
DESCRIPTION
writes the result into rdest. Rounding is according to the IEEE rounding mode bits in PCSW. If
IEEE exception, such as inexact, the corresponding exception flags in the PCSW are set. The PCSW exception flags
are sticky: the flags can be set as a side-effect of any floating-point operation but can only be reset by an explicit
writepcsw
other floating-point compute operations update the PCSW at the same time, the net result in each exception flag is the
logical OR of all simultaneous updates ORed with the existing PCSW value for that exception flag.
modification of the destination register. If the LSB of r guard is 1, rdest and the exception flags in PCSW are written;
otherwise, rdest is not changed and the operation does not affect the exception flags in PCSW.
EXAMPLES
r30 = 3
r40 = 0xffffffff (-1)
r10 = 0, r50 = 0xfffffffd
r20 = 1, r50 = 0xfffffffd
r60 = 0x7fffffff (2147483647)
r70 = 0x80000000 (-2147483648)
r80 = 0x7ffffff1 (2147483633)
The
The
The
[ IF rguard ] ifloat rsrc1
if rguard then {
}
rdest
ifloat
ifloatflags
ifloat
Initial Values
(float) ((long)rsrc1)
operation. The update of the PCSW exception flags occurs at the same time as r dest is written. If any
operation converts the signed integer value in rsrc1 to single-precision IEEE floating-point format and
operation optionally takes a guard, specified in rguard. If a guard is present, its LSB controls the
operation computes the exception flags that would result from an individual
ifloat r30
ifloat r40
IF r10 ifloat r50
IF r20 ifloat r50
ifloat r60
ifloat r70
ifloat r80
rdest
Operation
r100
r105
r117
r120
r122
r110
r115
PRELIMINARY SPECIFICATION
r100
r105
no change, since guard is false
r115
r117
r120
r122
PNX1300/01/02/11 DSPCPU Operations
0x40400000 (3.0)
0xbf800000 (-1.0)
0xc0400000 (–3.0)
0x4f000000 (2.147483648e+9), INX flag set
0xcf000000 (-2.147483648e+9)
0x4f000000 (2.147483648e+9), INX flag set
Function unit
Operation code
Number of operands
Modifier
Modifier range
Latency
Issue slots
ufloat ifloatrz ufloatrz
ifixieee ifloatflags
Result
ATTRIBUTES
SEE ALSO
ifloat
ifloat
ifloat
causes an
.
1, 4
falu
No
20
—
1
3
A-92