Pessimistic zero – FUJITSU Implementation Supplement Fujitsu SPARC64 V User Manual

Page 75

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SPARC JPS1 Implementation Supplement: Fujitsu SPARC64 V • Release 1.0, 1 July 2002

Pessimistic Zero

If a condition in

TABLE B-3

is

true

, SPARC64 V generates the result as a pessimistic

zero, meaning that the result is a denormalized minimum or a zero, depending on
the rounding mode (

FSR.RD

).

FMULs

,

FMULd

1. One of the operands is a denormalized number, the other operand is a normal,

nonzero floating-point number (except for a NaN and an infinity), and

single precision: -25 < Er
double precision: -54 < Er

2. Both operands are normal, nonzero floating-point numbers (except for a NaN and

an infinity),

TEM.UFM

= 0, and

single precision:

25 < eres < 1

double precision:

54 < eres < 1

FsMULd

1. One of the operands is a denormalized number, and the other operand is a normal,

nonzero floating-point number (except for a NaN and an infinity).

2. Both operands are denormalized numbers.

FDIVs

,

FDIVd

1. The dividend (operand1;

rs1

) is a normal, nonzero floating-point number (except

for a NaN and an infinity), the divisor (operand2; rs2) is a denormalized number,
and

single precision: Er < 255
double precision: Er < 2047

2. The dividend (operand1;

rs1

) is a denormalized number, the divisor (operand2;

rs2) is a normal, nonzero floating-point number (except for a NaN and an infinity),
and

single precision:

25 < Er

double precision:

54 < Er

3. Both operands are denormalized numbers.
4. Both operands are normal, nonzero floating-point numbers (except for a NaN and

an infinity),

TEM.UFM

= 0 and

single precision:

25 < eres < 1

double precision:

54 < eres < 1

FSQRTs

,

FSQRTd

The input operand (operand2; rs2) is a positive nonzero and is a denormalized
number.

1. Operation of 0 and denormalized number generates a result in accordance with the IEEE754-1985 standard.

TABLE B-2

unfinished_FPop

Boundary Conditions (Continued)

Operation

Boundary Conditions

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