
TM1300 Data Book
Philips Semiconductors
A-92
PRODUCT SPECIFICATION
IEEE status flags from convert signed integer to
floating-point
SYNTAX
[ IF rguard ] ifloatflags rsrc1
→
rdest
FUNCTION
if
rguard
then
rdest
←
ieee_flags((float) ((long)rsrc1))
ATTRIBUTES
Function unit
Operation code
Number of operands
Modifier
Modifier range
Latency
Issue slots
falu
130
1
No
—
3
1, 4
DESCRIPTION
The
ifloatflags
operation computes the IEEE exceptions that would result from converting the signed integer in
rsrc1 to a single-precision IEEE floating-point value, and an integer bit vector representing the computed exception
flags is written into rdest The bit vector stored in rdest has the same format as the IEEE exception bits in the PCSW.
The exception flags in PCSW are left unchanged by this operation. Rounding is according to the IEEE rounding mode
bits in PCSW.
The
ifloatflags
operation optionally takes a guard, specified in rguard If a guard is present, its LSB controls the
modification of the destination register. If the LSB of rguardis 1, rdestis written; otherwise, rdestis not changed.
EXAMPLES
Initial Values
Operation
Result
r30 = 3
r40 = 0xffffffff (-1)
r10 = 0, r50 = 0xfffffffd
r20 = 1, r50 = 0xfffffffd
r60 = 0x7fffffff (2147483647)
r70 = 0x80000000 (-2147483648)
r80 = 0x7ffffff1 (2147483633)
ifloatflags r30
→
r100
ifloatflags r40
→
r105
IF r10 ifloatflags r50
→
r110
IF r20 ifloatflags r50
→
r115
ifloatflags r60
→
r117
ifloatflags r70
→
r120
ifloatflags r80
→
r122
r100
←
0
r105
←
0
no change, since guard is false
r115
←
0
r117
←
0x02 (INX)
r120
←
0
r122
←
0x02 (INX)
OFZ
IFZ
INV
OVF
UNF
INX
DBZ
0
1
2
3
4
5
6
7
0
31
0
SEE ALSO
ifloat ifloatrzflags
ufloatflags ufloatrzflags
ifloatflags