tls: shrink sp_256_mod_mul_norm_10
function old new delta
sp_256_mod_mul_norm_10 1439 1405 -34
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/networking/tls_sp_c32.c b/networking/tls_sp_c32.c
index f9c66b1..c5e887a 100644
--- a/networking/tls_sp_c32.c
+++ b/networking/tls_sp_c32.c
@@ -460,51 +460,90 @@
static void sp_256_mod_mul_norm_10(sp_digit* r, const sp_digit* a)
{
int64_t t[8];
- int64_t a32[8];
int64_t o;
-
- a32[0] = a[0];
- a32[0] |= a[1] << 26;
- a32[0] &= 0xffffffff;
- a32[1] = (sp_digit)(a[1] >> 6);
- a32[1] |= a[2] << 20;
- a32[1] &= 0xffffffff;
- a32[2] = (sp_digit)(a[2] >> 12);
- a32[2] |= a[3] << 14;
- a32[2] &= 0xffffffff;
- a32[3] = (sp_digit)(a[3] >> 18);
- a32[3] |= a[4] << 8;
- a32[3] &= 0xffffffff;
- a32[4] = (sp_digit)(a[4] >> 24);
- a32[4] |= a[5] << 2;
- a32[4] |= a[6] << 28;
- a32[4] &= 0xffffffff;
- a32[5] = (sp_digit)(a[6] >> 4);
- a32[5] |= a[7] << 22;
- a32[5] &= 0xffffffff;
- a32[6] = (sp_digit)(a[7] >> 10);
- a32[6] |= a[8] << 16;
- a32[6] &= 0xffffffff;
- a32[7] = (sp_digit)(a[8] >> 16);
- a32[7] |= a[9] << 10;
- a32[7] &= 0xffffffff;
+ uint32_t a32;
/* 1 1 0 -1 -1 -1 -1 0 */
- t[0] = 0 + a32[0] + a32[1] - a32[3] - a32[4] - a32[5] - a32[6];
/* 0 1 1 0 -1 -1 -1 -1 */
- t[1] = 0 + a32[1] + a32[2] - a32[4] - a32[5] - a32[6] - a32[7];
/* 0 0 1 1 0 -1 -1 -1 */
- t[2] = 0 + a32[2] + a32[3] - a32[5] - a32[6] - a32[7];
/* -1 -1 0 2 2 1 0 -1 */
- t[3] = 0 - a32[0] - a32[1] + 2 * a32[3] + 2 * a32[4] + a32[5] - a32[7];
/* 0 -1 -1 0 2 2 1 0 */
- t[4] = 0 - a32[1] - a32[2] + 2 * a32[4] + 2 * a32[5] + a32[6];
/* 0 0 -1 -1 0 2 2 1 */
- t[5] = 0 - a32[2] - a32[3] + 2 * a32[5] + 2 * a32[6] + a32[7];
/* -1 -1 0 0 0 1 3 2 */
- t[6] = 0 - a32[0] - a32[1] + a32[5] + 3 * a32[6] + 2 * a32[7];
/* 1 0 -1 -1 -1 -1 0 3 */
- t[7] = 0 + a32[0] - a32[2] - a32[3] - a32[4] - a32[5] + 3 * a32[7];
+ // t[] should be calculated from "a" (converted from 26-bit to 32-bit vector a32[8])
+ // according to the above matrix:
+ //t[0] = 0 + a32[0] + a32[1] - a32[3] - a32[4] - a32[5] - a32[6] ;
+ //t[1] = 0 + a32[1] + a32[2] - a32[4] - a32[5] - a32[6] - a32[7] ;
+ //t[2] = 0 + a32[2] + a32[3] - a32[5] - a32[6] - a32[7] ;
+ //t[3] = 0 - a32[0] - a32[1] + 2*a32[3] + 2*a32[4] + a32[5] - a32[7] ;
+ //t[4] = 0 - a32[1] - a32[2] + 2*a32[4] + 2*a32[5] + a32[6] ;
+ //t[5] = 0 - a32[2] - a32[3] + 2*a32[5] + 2*a32[6] + a32[7] ;
+ //t[6] = 0 - a32[0] - a32[1] + a32[5] + 3*a32[6] + 2*a32[7];
+ //t[7] = 0 + a32[0] - a32[2] - a32[3] - a32[4] - a32[5] + 3*a32[7];
+ // We can do it "piecemeal" after each a32[i] is known, no need to store entire a32[8] vector:
+
+#define A32 (int64_t)a32
+ a32 = a[0] | (a[1] << 26);
+ t[0] = 0 + A32;
+ t[3] = 0 - A32;
+ t[6] = 0 - A32;
+ t[7] = 0 + A32;
+
+ a32 = (a[1] >> 6) | (a[2] << 20);
+ t[0] += A32 ;
+ t[1] = 0 + A32;
+ t[3] -= A32 ;
+ t[4] = 0 - A32;
+ t[6] -= A32 ;
+
+ a32 = (a[2] >> 12) | (a[3] << 14);
+ t[1] += A32 ;
+ t[2] = 0 + A32;
+ t[4] -= A32 ;
+ t[5] = 0 - A32;
+ t[7] -= A32 ;
+
+ a32 = (a[3] >> 18) | (a[4] << 8);
+ t[0] -= A32 ;
+ t[2] += A32 ;
+ t[3] += 2*A32;
+ t[5] -= A32 ;
+ t[7] -= A32 ;
+
+ a32 = (a[4] >> 24) | (a[5] << 2) | (a[6] << 28);
+ t[0] -= A32 ;
+ t[1] -= A32 ;
+ t[3] += 2*A32;
+ t[4] += 2*A32;
+ t[7] -= A32 ;
+
+ a32 = (a[6] >> 4) | (a[7] << 22);
+ t[0] -= A32 ;
+ t[1] -= A32 ;
+ t[2] -= A32 ;
+ t[3] += A32 ;
+ t[4] += 2*A32;
+ t[5] += 2*A32;
+ t[6] += A32 ;
+ t[7] -= A32 ;
+
+ a32 = (a[7] >> 10) | (a[8] << 16);
+ t[0] -= A32 ;
+ t[1] -= A32 ;
+ t[2] -= A32 ;
+ t[4] += A32 ;
+ t[5] += 2*A32;
+ t[6] += 3*A32;
+
+ a32 = (a[8] >> 16) | (a[9] << 10);
+ t[1] -= A32 ;
+ t[2] -= A32 ;
+ t[3] -= A32 ;
+ t[5] += A32 ;
+ t[6] += 2*A32;
+ t[7] += 3*A32;
+#undef A32
t[1] += t[0] >> 32; t[0] &= 0xffffffff;
t[2] += t[1] >> 32; t[1] &= 0xffffffff;
@@ -526,30 +565,16 @@
t[6] += t[5] >> 32; t[5] &= 0xffffffff;
t[7] += t[6] >> 32; t[6] &= 0xffffffff;
- r[0] = (sp_digit)(t[0]) & 0x3ffffff;
- r[1] = (sp_digit)(t[0] >> 26);
- r[1] |= t[1] << 6;
- r[1] &= 0x3ffffff;
- r[2] = (sp_digit)(t[1] >> 20);
- r[2] |= t[2] << 12;
- r[2] &= 0x3ffffff;
- r[3] = (sp_digit)(t[2] >> 14);
- r[3] |= t[3] << 18;
- r[3] &= 0x3ffffff;
- r[4] = (sp_digit)(t[3] >> 8);
- r[4] |= t[4] << 24;
- r[4] &= 0x3ffffff;
- r[5] = (sp_digit)(t[4] >> 2) & 0x3ffffff;
- r[6] = (sp_digit)(t[4] >> 28);
- r[6] |= t[5] << 4;
- r[6] &= 0x3ffffff;
- r[7] = (sp_digit)(t[5] >> 22);
- r[7] |= t[6] << 10;
- r[7] &= 0x3ffffff;
- r[8] = (sp_digit)(t[6] >> 16);
- r[8] |= t[7] << 16;
- r[8] &= 0x3ffffff;
- r[9] = (sp_digit)(t[7] >> 10);
+ r[0] = 0x3ffffff & ((sp_digit)(t[0]));
+ r[1] = 0x3ffffff & ((sp_digit)(t[0] >> 26) | ((sp_digit)t[1] << 6));
+ r[2] = 0x3ffffff & ((sp_digit)(t[1] >> 20) | ((sp_digit)t[2] << 12));
+ r[3] = 0x3ffffff & ((sp_digit)(t[2] >> 14) | ((sp_digit)t[3] << 18));
+ r[4] = 0x3ffffff & ((sp_digit)(t[3] >> 8) | ((sp_digit)t[4] << 24));
+ r[5] = 0x3ffffff & ((sp_digit)t[4] >> 2); /* small shift, ok to cast t[4] to narrower type */
+ r[6] = 0x3ffffff & ((sp_digit)(t[4] >> 28) | ((sp_digit)t[5] << 4));
+ r[7] = 0x3ffffff & ((sp_digit)(t[5] >> 22) | ((sp_digit)t[6] << 10));
+ r[8] = 0x3ffffff & ((sp_digit)(t[6] >> 16) | ((sp_digit)t[7] << 16));
+ r[9] = ((sp_digit)(t[7] >> 10));
}
/* Map the Montgomery form projective co-ordinate point to an affine point.
@@ -795,7 +820,7 @@
0x6b,0x17,0xd1,0xf2,0xe1,0x2c,0x42,0x47,0xf8,0xbc,0xe6,0xe5,0x63,0xa4,0x40,0xf2,0x77,0x03,0x7d,0x81,0x2d,0xeb,0x33,0xa0,0xf4,0xa1,0x39,0x45,0xd8,0x98,0xc2,0x96,
/* y */
0x4f,0xe3,0x42,0xe2,0xfe,0x1a,0x7f,0x9b,0x8e,0xe7,0xeb,0x4a,0x7c,0x0f,0x9e,0x16,0x2b,0xce,0x33,0x57,0x6b,0x31,0x5e,0xce,0xcb,0xb6,0x40,0x68,0x37,0xbf,0x51,0xf5,
- /* z will be set to 0, infinity flag to "false" */
+ /* z will be set to 1, infinity flag to "false" */
};
sp_point p256_base;