Rev. 6.0, 07/02, page 164 of 986
31
x
11111111
Nxxxxxxxxxxxxxxxxxxxxxx
30
23 22
0
N = 1: sNaN
N = 0: qNaN
Figure 6.3 Single-Precision NaN Bit Pattern
An sNaN is input in an operation, except copy, FABS, and FNEG, that generates a floating-point
value.
•
When the EN.V bit in the FPSCR register is 0, the operation result (output) is a qNaN.
•
When the EN.V bit in the FPSCR register is 1, an invalid operation exception will be
generated. In this case, the contents of the operation destination register are unchanged.
If a qNaN is input in an operation that generates a floating-point value, and an sNaN has not been
input in that operation, the output will always be a qNaN irrespective of the setting of the EN.V bit
in the FPSCR register. An exception will not be generated in this case.
The qNAN values generated by the SH7750 Series as operation results are as follows:
•
Single-precision qNaN: H'7FBFFFFF
•
Double-precision qNaN: H'7FF7FFFF FFFFFFFF
See the individual instruction descriptions for details of floating-point operations when a non-
number (NaN) is input.
6.2.3
Denormalized Numbers
For a denormalized number floating-point value, the exponent field is expressed as 0, and the
fraction field as a non-zero value.
When the DN bit in the FPU’s status register FPSCR is 1, a denormalized number (source operand
or operation result) is always flushed to 0 in a floating-point operation that generates a value (an
operation other than copy, FNEG, or FABS).
When the DN bit in FPSCR is 0, a denormalized number (source operand or operation result) is
processed as it is. See the individual instruction descriptions for details of floating-point
operations when a denormalized number is input.
Summary of Contents for SH7750 series
Page 106: ...Rev 6 0 07 02 page 56 of 986 ...
Page 144: ...Rev 6 0 07 02 page 94 of 986 ...
Page 242: ...Rev 6 0 07 02 page 192 of 986 ...
Page 270: ...Rev 6 0 07 02 page 220 of 986 ...
Page 360: ...Rev 6 0 07 02 page 310 of 986 ...
Page 538: ...Rev 6 0 07 02 page 488 of 986 ...
Page 706: ...Rev 6 0 07 02 page 656 of 986 ...
Page 752: ...Rev 6 0 07 02 page 702 of 986 ...
Page 780: ...Rev 6 0 07 02 page 730 of 986 ...
Page 822: ...Rev 6 0 07 02 page 772 of 986 ...
Page 986: ...Rev 6 0 07 02 page 936 of 986 ...
Page 1030: ...Rev 6 0 07 02 page 980 of 986 ...
Page 1036: ...Rev 6 0 07 02 page 986 of 986 ...