gf128_add can be marked as __pure2

[Eitan Adler]

Is there any reason not to apply this patch?

__pure2 means __attribute__((const)) which is correct in this case as
gf128_add read no global memory:


Index: gfmult.h
===================================================================
--- gfmult.h (revision 329611)
+++ gfmult.h (working copy)
@@ -108,7 +108,7 @@ gf128_write(struct gf128 v, uint8_t *buf)
be64enc(buf, v.v[1]);
}

-static inline struct gf128 __pure /* XXX - __pure2 instead */
+static inline struct gf128 __pure2
gf128_add(struct gf128 a, struct gf128 b)
{
a.v[0] ^= b.v[0];

[John-Mark Gurney]

Post by Eitan Adler
Is there any reason not to apply this patch?

I don't see why there wouldn't be..

Post by Eitan Adler
__pure2 means __attribute__((const)) which is correct in this case as

Are these documented some where? Looksl ike __pure2 was created instead
of using __pure for some reason... I wish these things were documented
properly so others could know the correct usage...

Post by Eitan Adler
Index: gfmult.h
===================================================================
--- gfmult.h (revision 329611)
+++ gfmult.h (working copy)
@@ -108,7 +108,7 @@ gf128_write(struct gf128 v, uint8_t *buf)
be64enc(buf, v.v[1]);
}
-static inline struct gf128 __pure /* XXX - __pure2 instead */
+static inline struct gf128 __pure2
gf128_add(struct gf128 a, struct gf128 b)
{
a.v[0] ^= b.v[0];

[Eitan Adler]

Post by John-Mark Gurney

Post by Eitan Adler
Is there any reason not to apply this patch?

I don't see why there wouldn't be..

Post by Eitan Adler
__pure2 means __attribute__((const)) which is correct in this case as

Are these documented some where? Looksl ike __pure2 was created instead
of using __pure for some reason... I wish these things were documented
properly so others could know the correct usage...

I don't know where the FreeBSD macros are documented (they are
implementedi cdefs.h).
https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#Common-Function-Attributes
documents the attributes

__pure2 is const
__pure is pure

[Eitan Adler]

Post by John-Mark Gurney

Post by Eitan Adler
Is there any reason not to apply this patch?

I don't see why there wouldn't be..

Post by Eitan Adler
__pure2 means __attribute__((const)) which is correct in this case as

For extra clarity, since this is crypto related, can you please accept
here: https://reviews.freebsd.org/D15786