2.14 VFP Support

The compiler includes support for generating vector floating-point (VFP) co-processor instructions through the --float_support=vfp option. The VFP co-processor is available in many variants of ARM11 and higher. The valid vfp entries are:

vfpv2

Allows generation of floating point instructions for ARM9E.

vfpv3

Allows generation of floating point instructions for Cortex-A8.

vfpv3d16

Allows generation of floating point instructions for Cortex-R4.

fpv4spd16

Allows generation of floating point instructions for Cortex-M4.

none

Disables hardware floating point support. Specifies that the compiler implements floating point operations in software.

Using the --silicon_version=7M4 command-line option automatically sets the --float_support=fpv4spd16 option. To disable hardware floating point support, use the --float_support=none option.

This is the current support for VFP:

You must link any VFP compiled code with a separate version of the run-time support library. See Section 7.1.8 for information on library-naming conventions.
The compiler follows the VFP argument passing and returning calling convention for qualified VFP arguments.
Object files that do not contain any functions with floating point arguments or return values can be linked with both VFP and non-VFP files.
Object files that do contain functions with floating point arguments or return values can only be linked with objects that were compiled with matching VFP support.
All hand-coded VFP assembly must follow VFP calling conventions and EABI conventions to correctly compile and link. In addition to these, the appropriate VFP build attributes for EABI must be correctly set.
The compile-time predefined macro __TI_VFP_SUPPORT__ can be used for conditionally compiling/assembling user code. VFP-specific user code can use this macro to ensure that the conditionally included code is compiled only when VFP is enabled.

Refer to the ARM architecture manual for more details on the VFPv3 and VFPv3D16 architectures and ISAs. Refer to the ARM AAPCS and EABI documents for more details on VFP calling conventions and build attributes.