About fpr usage in mips64

Ian Lance Taylor iant@google.com
Wed Nov 30 10:53:00 GMT 2011

Heiher <admin@heiher.info> writes:

> The o32 abi programs could only use even-numbered floating-point
> registers by appointment. The GCC generate assembly source  code using
> odd-numbered floating-point register when I -march=mips64 and
> -mabi=32. Every double floating-point instructions will use 32-bit
> even/odd-numbered paired 64-bit fpr when 0 = bit FR in Status
> register. However kernel set bit FR to a thread at loading ELF for N32
> or 64 only. In other words, o32 abi process can't use odd-numbered
> fpr.
> How ought I to act? Thanks!

I'm not sure it makes sense to use -march=mips64 -mabi=32.  Why do you
want to do that?

You could try using the -mfp32 option but I don't know whether it will


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