Fujitsu Fujitsu SPARC64 V manual Pessimistic Zero, Table B-2unfinishedFPop Boundary Conditions

Models: Fujitsu SPARC64 V

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TABLE B-2unfinished_FPop Boundary Conditions (Continued)

Operation

Boundary Conditions

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.

Pessimistic Zero

If a condition in TABLE B-3is 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).

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

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Fujitsu Fujitsu SPARC64 V manual Pessimistic Zero, Table B-2unfinishedFPop Boundary Conditions