bn/asm/rsax-avx2.pl: minor optimization [for Decoded ICache].

[oweals/openssl.git] / crypto / bn / bn_exp.c

diff --git a/crypto/bn/bn_exp.c b/crypto/bn/bn_exp.c
index b17b5694fcb8ac102f62c1759be955bc533b97df..6e3a7264d5141197dda2ac7d2da3d6546fdc9701 100644 (file)
--- a/crypto/bn/bn_exp.c
+++ b/crypto/bn/bn_exp.c
@@ -128,6 +128,14 @@
 # include <alloca.h>
 #endif
 
+#undef RSAZ_ENABLED
+#if defined(OPENSSL_BN_ASM_MONT) && \
+       (defined(__x86_64) || defined(__x86_64__) || \
+        defined(_M_AMD64) || defined(_M_X64))
+# include "rsaz_exp.h"
+# define RSAZ_ENABLED
+#endif
+
 #undef SPARC_T4_MONT
 #if defined(OPENSSL_BN_ASM_MONT) && (defined(__sparc__) || defined(__sparc))
 # include "sparc_arch.h"
@@ -677,6 +685,36 @@ int BN_mod_exp_mont_consttime(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p,
                if (!BN_MONT_CTX_set(mont,m,ctx)) goto err;
                }
 
+#ifdef RSAZ_ENABLED
+       /*
+        * If the size of the operands allow it, perform the optimized
+        * RSAZ exponentiation. For further information see
+        * crypto/bn/rsaz_exp.c and accompanying assembly modules.
+        */
+       if (((OPENSSL_ia32cap_P[2]&0x80100) != 0x80100) /* check for MULX/AD*X */
+           && (16 == a->top) && (16 == p->top) && (BN_num_bits(m) == 1024)
+           && rsaz_avx2_eligible())
+               {
+               if (NULL == bn_wexpand(rr, 16)) goto err;
+               RSAZ_1024_mod_exp_avx2(rr->d, a->d, p->d, m->d, mont->RR.d, mont->n0[0]);
+               rr->top = 16;
+               rr->neg = 0;
+               bn_correct_top(rr);
+               ret = 1;
+               goto err;
+               }
+       else if ((8 == a->top) && (8 == p->top) && (BN_num_bits(m) == 512))
+               {
+               if (NULL == bn_wexpand(rr,8)) goto err;
+               RSAZ_512_mod_exp(rr->d, a->d, p->d, m->d, mont->n0[0], mont->RR.d);
+               rr->top = 8;
+               rr->neg = 0;
+               bn_correct_top(rr);
+               ret = 1;
+               goto err;
+               }
+#endif
+
        /* Get the window size to use with size of p. */
        window = BN_window_bits_for_ctime_exponent_size(bits);
 #if defined(SPARC_T4_MONT)