Delphi in a Nutshell

Name

TestFDIV Variable

Syntax

var TestFDIV: ShortInt;

Description

The TestFDIV variable tells whether the floating-point processor has a correct implementation of the FDIV instruction.

If you use the $U or $SafeDivide compiler directive, all floating-point division operations call a function that tests the floating-point processor for the infamous Pentium FDIV bug. If the bug is present, future divisions will be performed by a software subroutine that gives the correct answer. If the bug is not present, future divisions will be performed by the floating-point hardware.

The TestFDIV variable contains one of the following values:

-1

The processor is flawed and will be bypassed.

0

The processor has not yet been tested.

1

The processor has been tested and is correct.

Tips and Tricks

TestFDIV exists for backward compatibility only. Windows handles this problem in the operating system.

See Also

$SafeDivide Compiler Directive, $U Compiler Directive