Possible Operand Errors Exceptions - Motorola M68060 User Manual

Table 6-12. Possible Operand Errors Exceptions
Instruction
FADD
FDIV
FMOVE to B,W,or L
FMUL
FSQRT
FSUB
FACOS
FASIN
FATANH
FCOS
FGETEXP
FGETMAN
FLOG10
FLOG2
FLOGN
FLOGNP1
FMOD
FMOVE to P
FREM
FSCALE
FSGLDIV
FSGLMUL
FSIN
FSINCOS
FTAN
6.6.3.1 TRAP DISABLED RESULTS (FPCR OPERR BIT CLEARED). For
OUT instruction with the format S, D, or X, an OPERR is impossible. For an FMOVE OUT
instruction with the format B, W, or L, an OPERR is possible only on an integer overflow, if
the source is an infinity, or if the source is a NAN. On the integer overflow and infinity source
cases, the largest positive or negative integer that can fit in the specified destination size (B,
W, or L) is stored. On the NAN source case, the 8, 16, or 32 most significant bits of the NAN
significand is stored in the B, W, or L destination.
For FMOVE OUT with the format P (packed decimal), if the k-factor is greater than +17, the
result returned is a packed decimal string that assumes a k-factor equal to +17. For packed
decimal results where the absolute value of the exponent is greater than 999, the decimal
string is returned with the three least significant exponent digits in EXP2, EXP1, and EXP0.
The fourth digit, EXP3, is supplied in the most significant four bits of the third byte in the
string.
For all other OPERR cases, the destination is a floating-point data register. An extended-
precision non-signaling NAN is stored in the destination.
6.6.3.2 TRAP ENABLED RESULTS (FPCR OPERR BIT SET). For
cases, the destination is written as if the trap were disabled, and then control is passed to
MOTOROLA
Condition Causing Operand Error
Native to MC68060
[(+∞) + (–∞)] or [(–∞) + (+∞)]
(0 ÷ 0) or (∞ ÷ ∞)
Integer overflow, source is nonsignaling NAN or ±∞
One operand is 0 and other is +∞
(Source < 0) or (−∞)
[(+∞) – (+∞)] or [(–∞) – (–∞)]
Non-Native to MC68060
Source is ±∞, > +1, or < –1
Source is ±∞, > +1, or < –1
Source is ±∞, > +1, or < –1
Source is ±∞
Source is ±∞
Source is ±∞
Source is < 0 or −∞
Source is < 0 or −∞
Source is < 0 or −∞
Source is ≤ 1 or −∞
Floating-point data register is ±∞ or source is 0, other operand is not a NAN
Source exponent > 999 (decimal) or k-factor > 17
Floating-point data register is ±∞ or source is 0, other operand is not a NAN
Source is ±∞, other operand not a NAN
(0 ÷ 0) or(∞ ÷ ∞)
One operand is 0, other operand is ∞
Source is ±∞
Source is ±∞
Source is ±∞
M68060 USER'S MANUAL
Floating-Point Unit
an FMOVE
the FMOVE OUT
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