C-1
APPENDIX C
FLOATING-POINT EXCEPTIONS SUMMARY
Table C-1 lists the floating-point instruction mnemonics in alphabetical order. For each
mnemonic, it summarizes the exceptions that the instruction may cause. Refer to Section 7.8.,
Floating-Point Exception Conditions in Chapter 7, Floating-Point Unit for a detailed discus-
sion of the floating-point exceptions. The following codes indicate the floating-point excep-
tions:
#IS
Invalid operation exception for stack underflow or stack overflow.
#IA
Invalid operation exception for invalid arithmetic operands and
unsupported formats.
#D
Denormal operand exception.
#Z
Divide-by-zero exception.
#
O
Numeric overflow exception.
#U
Numeric underflow exception.
#P
Inexact result (precision) exception.
Table C-1. Floating-Point Exceptions Summary
Mnemonic
Instruction
#IS#IA#D#Z#O#U#P
F2XM1
2
X
1
YYY
YY
FABS
Absolute value
Y
FADD(P)
Add real
YYY
YYY
FBLD
BCD load
Y
FBSTP
BCD store and pop
YY
Y
FCHS
Change sign
Y
FCLEX
Clear exceptions
FCMOVcc
Floating-point conditional moveY
FCOM, FCOMP, FCOMPPCompare real
YYY
FCOMI, FCOMIP, FUCOMI,
FUCOMIP
Compare real and set EFLAGSYY
FCOS
Cosine
YYY
YY
FDECSTP
Decrement stack pointer
FDIV(R)(P)
Divide real
YYYYYYY