18.4.4. RunFast Mode

RunFast mode is the combination of the following conditions:

In RunFast mode the VFP9-S coprocessor:

RunFast mode enables the programmer to write code for the VFP9-S coprocessor that runs in a determinable time without support code assistance, regardless of the characteristics of the input data. In RunFast mode, no user exception traps are available. However, the exception flags in the FPSCR register are compliant with the IEEE 754 standard for Inexact, Overflow, Invalid Operation, and Division-by-Zero exceptions. The underflow flag is modified for Flush-to-Zero mode. Each of these flags is set by an exceptional condition and can be cleared only by a write to the FPSCR register.

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