Amitay Isaacs <ami...@ozlabs.org> writes: > --- /dev/null > +++ b/powerpc64/ecc-curve25519-modp.asm > @@ -0,0 +1,101 @@ > +C powerpc64/ecc-25519-modp.asm > +define(`RP', `r4') > +define(`XP', `r5') > + > +define(`U0', `r6') C Overlaps unused modulo input > +define(`U1', `r7') > +define(`U2', `r8') > +define(`U3', `r9') > +define(`T0', `r10') > +define(`T1', `r11') > +define(`M', `r12') > + > +define(`UN', r3)
Comment seems misplaced, it's UN / r3 that overlaps the unused input, right? > + C void ecc_curve25519_modp (const struct ecc_modulo *p, mp_limb_t *rp, > mp_limb_t *xp) > + .text > +define(`FUNC_ALIGN', `5') > +PROLOGUE(_nettle_ecc_curve25519_modp) > + > + C First fold the limbs affecting bit 255 > + ld UN, 56(XP) > + li M, 38 > + mulhdu T1, M, UN > + mulld UN, M, UN > + ld U3, 24(XP) > + li T0, 0 > + addc U3, UN, U3 > + adde T0, T1, T0 > + > + ld UN, 40(XP) > + mulhdu U2, M, UN > + mulld UN, M, UN > + > + addc U3, U3, U3 > + adde T0, T0, T0 > + srdi U3, U3, 1 C Undo shift, clear high bit > + > + C Fold the high limb again, together with RP[5] > + li T1, 19 > + mulld T0, T1, T0 > + ld U0, 0(XP) > + ld U1, 8(XP) > + ld T1, 16(XP) > + addc U0, T0, U0 > + adde U1, UN, U1 > + ld T0, 32(XP) > + adde U2, U2, T1 > + addze U3, U3 > + > + mulhdu T1, M, T0 > + mulld T0, M, T0 > + addc U0, T0, U0 > + adde U1, T1, U1 > + std U0, 0(RP) > + std U1, 8(RP) > + > + ld T0, 48(XP) > + mulhdu T1, M, T0 > + mulld UN, M, T0 > + adde U2, UN, U2 > + adde U3, T1, U3 > + std U2, 16(RP) > + std U3, 24(RP) > + > + blr > +EPILOGUE(_nettle_ecc_curve25519_modp) Looks good. I must admit that the x86_64 version this is based on is not so easy to follow. Regards, /Niels -- Niels Möller. PGP key CB4962D070D77D7FCB8BA36271D8F1FF368C6677. Internet email is subject to wholesale government surveillance. _______________________________________________ nettle-bugs mailing list nettle-bugs@lists.lysator.liu.se http://lists.lysator.liu.se/mailman/listinfo/nettle-bugs
