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[RFC][ARM] Naming for new switch to check for mixed hardfloat/softfloat compat

[Please CC me as I'm not subscribed to this list]

Hi there,

I'm currently working on adding a switch to check whether public function involve float parameters or return values. Such a check would be useful for people trying to write code that is compatible with both base standard (softfloat) and standard variant (hardfloat) ARM calling convention. I also intend to set the ELF attribute Tag_ABI_VFP_args to value 3 (code compatible with both ABI) so this check would allow to make sure such value would be set.

I initially thought about reusing -mfloat-abi with the value none for that purpose since it would somehow define a new ABI where no float can be used. However, it would then not be possible to forbit float in public interface with the use of VFP instructions for float arithmetic (softfp) because this switch conflates the float ABI with the use of a floating point unit for float arithmetic. Also, gcc passes -mfloat-abi down to the assembler and that would mean teaching the assembler about -mfloat-abi=none as well.

I thus think that a new switch would be better and am asking for your opinion about it as I would like this functionality to incorporate gcc codebase.

Best regards,

Thomas Preud'homme

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