4
FLOG10
Log10
FLOG10
Operation:
Loglo of Source J FPn
Assembler FLOG10.<fmt> <ea>,FPn
Syntax: FLOG10.X FPm,FPn
FLOG10.X FPn
Attributes: Format= (Byte, Word, Long, Single, Double, Extended, Packed)
Description: Convert the source operand to extended precision (if necessary) and cal-
culates the logarithm of that number using base 10 arithmetic. Stores the result in the
destination floating-point data register. This function is not defined for input values
less than zero.
Operation Table:
_-•_
Source In Range
Destination ~_ +
Result Log10 NAN 1
Zero
+
- inf2
Infinity
+
+ inf t~AN 1
NOTES:
1. Sets the OPERR bit in the FPSR
exception
byte.
2. Sets the DZ bit in the FPSR exception byte.
3. If the source operand is a NAN, refer to 4°5.4 NANs for more information,
Status
Register:
Condition Codes:
Affected as described in 4.5.5.1 SETTING FLOATING-POINT
CONDITION
CODES
Quotient Byte: Not affected
Exception Byte: BSUN
SNAN
OPERR
Accrued Exception Byte:
Instruction Format:
15 14 13
1 I
Cleared
Refer to 4.5.4 NANs.
Set if the source operand is <0; cleared
otherwise
OVFL Cleared
UNFL Cleared
DZ Set if the source is (+ or -); cleared otherwise
INEX2 Refer to 6.1.7 Inexact Result.
INEXl If <fmt> is Packed, refer to 6.1.8 Inexact Result
on Decimal Input; cleared otherwise.
Affected as described in 6.1.10 IEEE Exception and Trap Com-
patibility
0 R/M 0
12 11 10 9 8 7 G 5 4 3 2 t 0
I COPROCESSOR [ l ID EFFECTIVEt ADDRESS |
1 O 0 0 MODE REGISTER
SOURCE DESTINATION
SPECIFIER REGISTER O 0 1 0 1 0 1
=
FREESCALE
4-54
MC68881/MC68882 USER'S MANUAL
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