1.8. VFP11 treatment of branch instructions

The VFP11 coprocessor does not provide branch instructions directly. Instead, the result of a floating-point compare instruction can be stored in the ARM1136 condition code flags using the FMSTAT instruction. This means you can use the ARM1136 branch instructions and conditional execution capability for executing conditional floating-point code.

In some cases, full IEEE 754 standard comparisons are not required. You can make simple comparisons of single-precision data, such as comparisons to zero or to a constant, using an FMRS transfer and the ARM11 CMP and CMN instructions. This method is faster in many cases than using an FCMP instruction followed by an FMSTAT instruction. For more information, see Compliance with the IEEE 754 standard and Comparisons.

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