4.41 Default selection of hardware or software floating-point support

The default target FPU architecture is derived from use of the --cpu option.

If the processor specified with --cpu has a VFP coprocessor, the default target FPU architecture is the VFP architecture for that processor. For example, the option --cpu ARM1136JF-S implies the option --fpu vfpv2.
If a VFP coprocessor is present, VFP instructions are generated. If there is no VFP coprocessor, the compiler generates code that makes calls to the software floating-point library fplib to carry out floating-point operations. fplib is available as part of the standard distribution of the ARM compilation tools suite of C libraries.
Related concepts
4.40 Compiler support for floating-point arithmetic
4.42 Example of hardware and software support differences for floating-point arithmetic
4.43 Vector Floating-Point (VFP) architectures
4.44 Limitations on hardware handling of floating-point arithmetic
4.45 Implementation of Vector Floating-Point (VFP) support code
4.46 Compiler and library support for half-precision floating-point numbers
4.47 Half-precision floating-point number format
4.48 Compiler support for floating-point computations and linkage
4.49 Types of floating-point linkage
4.50 Compiler options for floating-point linkage and computations
Related reference
4.51 Floating-point linkage and computational requirements of compiler options
4.52 Processors and their implicit Floating-Point Units (FPUs)
Related information
Floating-point Support
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