diff options
Diffstat (limited to 'openssl/crypto/bn/bn_asm.c')
| -rw-r--r-- | openssl/crypto/bn/bn_asm.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/openssl/crypto/bn/bn_asm.c b/openssl/crypto/bn/bn_asm.c index c43c91cc0..a33b63411 100644 --- a/openssl/crypto/bn/bn_asm.c +++ b/openssl/crypto/bn/bn_asm.c @@ -438,6 +438,10 @@ BN_ULONG bn_sub_words(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b, int n) /* sqr_add_c(a,i,c0,c1,c2) -- c+=a[i]^2 for three word number c=(c2,c1,c0) */ /* sqr_add_c2(a,i,c0,c1,c2) -- c+=2*a[i]*a[j] for three word number c=(c2,c1,c0) */ +/* + * Keep in mind that carrying into high part of multiplication result + * can not overflow, because it cannot be all-ones. + */ #ifdef BN_LLONG #define mul_add_c(a,b,c0,c1,c2) \ t=(BN_ULLONG)a*b; \ @@ -478,10 +482,10 @@ BN_ULONG bn_sub_words(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b, int n) #define mul_add_c2(a,b,c0,c1,c2) { \ BN_ULONG ta=(a),tb=(b),t0; \ BN_UMULT_LOHI(t0,t1,ta,tb); \ - t2 = t1+t1; c2 += (t2<t1)?1:0; \ - t1 = t0+t0; t2 += (t1<t0)?1:0; \ - c0 += t1; t2 += (c0<t1)?1:0; \ + c0 += t0; t2 = t1+((c0<t0)?1:0);\ c1 += t2; c2 += (c1<t2)?1:0; \ + c0 += t0; t1 += (c0<t0)?1:0; \ + c1 += t1; c2 += (c1<t1)?1:0; \ } #define sqr_add_c(a,i,c0,c1,c2) { \ @@ -508,10 +512,10 @@ BN_ULONG bn_sub_words(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b, int n) BN_ULONG ta=(a),tb=(b),t0; \ t1 = BN_UMULT_HIGH(ta,tb); \ t0 = ta * tb; \ - t2 = t1+t1; c2 += (t2<t1)?1:0; \ - t1 = t0+t0; t2 += (t1<t0)?1:0; \ - c0 += t1; t2 += (c0<t1)?1:0; \ + c0 += t0; t2 = t1+((c0<t0)?1:0);\ c1 += t2; c2 += (c1<t2)?1:0; \ + c0 += t0; t1 += (c0<t0)?1:0; \ + c1 += t1; c2 += (c1<t1)?1:0; \ } #define sqr_add_c(a,i,c0,c1,c2) { \ |