FPEmulator_DeactivateContext (changes)

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FPEmulator

» SWI Calls

» FPEmulator_DeactivateContext

FPEmulator_DeactivateContext

(SWI &40481)

Use

The purpose of this call is to deactivate the current floating point context, ensuring that everything about the context is held in memory.

Notes

You should normally use FPEmulator_ChangeContext in preference to this call.

It returns the address of the current floating point context, or zero if the floating point system is in the completely disabled state described under FPEmulator_ChangeContext.

Note that these calls should be made in pairs, with an FPEmulator_ActivateContext call following each FPEmulator_DeactivateContext call, Also, you should not allow any floating point instructions to be executed between an FPEmulator_DeactivateContext call and the following FPEmulator_ActivateContext call, since executing a floating point instruction will re-activate the context and mean that the memory context may no longer be up-to-date.

Exception: it is legitimate to leave out the call to FPEmulator_DeactivateContext in the above sequence, but only if the old context is never going to be used again: it is likely to be in an inconsistent state if the FPEmulator_DeactivateContext call is omitted.

Contexts are only available from FPEmulator 4.12 and later.

See also

• Floating Point Contexts
• FPEmulator_ActivateContext
• FPEmulator_ChangeContext