Totalview® for HPC Reference Guide : PART III Platforms and Operating Systems : Chapter 11 Architectures : Intel IA-64 : Floating Point Status Register Fields
Floating Point Status Register Fields
The Floating-Point Status Register (FPSR) contains the dynamic control and status information for floating-point operations. There is one main set of control and status information and three alternate sets.
Field
Bits
Meaning
traps.vd
0
Invalid Operation Floating-Point Exception fault disabled
traps.dd
1
Denormal/Unnormal Operating Floating-Point Exception fault disabled
traps.zd
2
Zero Divide Floating-Point Exception trap disabled
traps.od
3
Overflow Floating-Point Exception trap disabled
traps.ud
4
Underflow Floating-Point Exception trap disabled
traps.id
5
Inexact Floating-Point Exception trap disabled
sfo
18:6
main status field
sf1
31:19
alternate status field 1
sf2
44:32
alternate status field 2
sf3
57:45
alternate status field 3
Here is a description of the FPSR status field descriptions.
Bits
Field
meaning
0
ftz
flush-to-zero mode
1
wre
widest range exponent
3:2
pc
precision control
5:4
rc
rounding control
6
td
traps disabled
7
v
invalid operation
8
d
denormal/unnormal operand
9
z
zero divide
10
o
overflow
11
u
underflow
12
i
inexact