"Maciej W. Rozycki" <ma...@codesourcery.com> writes:
> On Sat, 16 Nov 2013, Richard Sandiford wrote:
>
>> > Index: gcc-fsf-trunk-quilt/gcc/config/mips/mips.h
>> > ===================================================================
>> > --- gcc-fsf-trunk-quilt.orig/gcc/config/mips/mips.h 2013-11-12
>> > 15:31:46.758734464 +0000
>> > +++ gcc-fsf-trunk-quilt/gcc/config/mips/mips.h 2013-11-12
>> > 15:33:22.277646941 +0000
>> > @@ -921,6 +921,21 @@ struct mips_cpu_info {
>> > 'c = -((a * b) [+-] c)'. */
>> > #define ISA_HAS_NMADD3_NMSUB3 TARGET_LOONGSON_2EF
>> >
>> > +/* ISA has floating-point RECIP.fmt and RSQRT.fmt instructions. The
>> > + MIPS64 rev. 1 ISA says that RECIP.D and RSQRT.D are unpredictable when
>> > + doubles are stored in pairs of FPRs, so for safety's sake, we apply
>> > + this restriction to the MIPS IV ISA too. */
>> > +#define ISA_HAS_FP_RECIP_RSQRT(MODE)
>> > \
>> > + (((ISA_HAS_FP4 \
>> > + || (ISA_MIPS32R2 && !TARGET_MIPS16)) \
>> > + && ((MODE) == SFmode \
>> > + || ((TARGET_FLOAT64 \
>> > + || !(ISA_MIPS4 \
>> > + || ISA_MIPS64)) \
>> > + && (MODE) == DFmode))) \
>> > + || ((TARGET_SB1 && !TARGET_MIPS16) \
>> > + && (MODE) == V2SFmode))
>>
>> I think the !(ISA_MIPS4 || ISA_MIPS64) part is really "r2 or later",
>> which elsewhere we test as "ISA_MIPS32R2 || ISA_MIPS64R2". Obviously
>> that isn't as future-proof, but I think consistency wins here.
>> (E.g. the earlier ISA_MIPS32R2 seems like it's reallly "r2 or later" too).
>>
>> Cleaning up these macros has been on my todo list for about ten years :-(
>
> Code follows the comment (or vice versa) to make it easier for the reader
> to understand what's going on here, however if you plan to revamp these
> macros, then I'm leaving it up to you.
Ah, sorry, I hadn't meant it that way. I'm happy with the split of
ISA_HAS_* macros into features, including those you're making here.
The cleanup I meant was to replace the long lists of ISA_MIPS* tests
with something a bit shorter and more future-proof. E.g. something
similar to the __mips and __mips_isa_rev that we provide for users.
Thanks,
Richard
