Add another Ed25519 helper to save a few hundred redundant lines

No impact on performance.

1 files changed, 14 insertions, 108 deletions

diff --git a/src/lib/pubkey/ed25519/sc_reduce.cpp b/src/lib/pubkey/ed25519/sc_reduce.cpp
index ec8f94955..b9d0f9527 100644
--- a/src/lib/pubkey/ed25519/sc_reduce.cpp
+++ b/src/lib/pubkey/ed25519/sc_reduce.cpp
@@ -51,53 +51,12 @@ void sc_reduce(uint8_t* s)
    int64_t s22 = MASK & (load_4(s + 57) >> 6);
    int64_t s23 = (load_4(s + 60) >> 3);
 
-   s11 += s23 * 666643;
-   s12 += s23 * 470296;
-   s13 += s23 * 654183;
-   s14 -= s23 * 997805;
-   s15 += s23 * 136657;
-   s16 -= s23 * 683901;
-   s23 = 0;
-
-   s10 += s22 * 666643;
-   s11 += s22 * 470296;
-   s12 += s22 * 654183;
-   s13 -= s22 * 997805;
-   s14 += s22 * 136657;
-   s15 -= s22 * 683901;
-   s22 = 0;
-
-   s9 += s21 * 666643;
-   s10 += s21 * 470296;
-   s11 += s21 * 654183;
-   s12 -= s21 * 997805;
-   s13 += s21 * 136657;
-   s14 -= s21 * 683901;
-   s21 = 0;
-
-   s8 += s20 * 666643;
-   s9 += s20 * 470296;
-   s10 += s20 * 654183;
-   s11 -= s20 * 997805;
-   s12 += s20 * 136657;
-   s13 -= s20 * 683901;
-   s20 = 0;
-
-   s7 += s19 * 666643;
-   s8 += s19 * 470296;
-   s9 += s19 * 654183;
-   s10 -= s19 * 997805;
-   s11 += s19 * 136657;
-   s12 -= s19 * 683901;
-   s19 = 0;
-
-   s6 += s18 * 666643;
-   s7 += s18 * 470296;
-   s8 += s18 * 654183;
-   s9 -= s18 * 997805;
-   s10 += s18 * 136657;
-   s11 -= s18 * 683901;
-   s18 = 0;
+   redc_mul(s11, s12, s13, s14, s15, s16, s23);
+   redc_mul(s10, s11, s12, s13, s14, s15, s22);
+   redc_mul( s9, s10, s11, s12, s13, s14, s21);
+   redc_mul( s8,  s9, s10, s11, s12, s13, s20);
+   redc_mul( s7,  s8,  s9, s10, s11, s12, s19);
+   redc_mul( s6,  s7,  s8,  s9, s10, s11, s18);
 
    carry<21>(s6, s7);
    carry<21>(s8, s9);
@@ -112,53 +71,12 @@ void sc_reduce(uint8_t* s)
    carry<21>(s13, s14);
    carry<21>(s15, s16);
 
-   s5 += s17 * 666643;
-   s6 += s17 * 470296;
-   s7 += s17 * 654183;
-   s8 -= s17 * 997805;
-   s9 += s17 * 136657;
-   s10 -= s17 * 683901;
-   s17 = 0;
-
-   s4 += s16 * 666643;
-   s5 += s16 * 470296;
-   s6 += s16 * 654183;
-   s7 -= s16 * 997805;
-   s8 += s16 * 136657;
-   s9 -= s16 * 683901;
-   s16 = 0;
-
-   s3 += s15 * 666643;
-   s4 += s15 * 470296;
-   s5 += s15 * 654183;
-   s6 -= s15 * 997805;
-   s7 += s15 * 136657;
-   s8 -= s15 * 683901;
-   s15 = 0;
-
-   s2 += s14 * 666643;
-   s3 += s14 * 470296;
-   s4 += s14 * 654183;
-   s5 -= s14 * 997805;
-   s6 += s14 * 136657;
-   s7 -= s14 * 683901;
-   s14 = 0;
-
-   s1 += s13 * 666643;
-   s2 += s13 * 470296;
-   s3 += s13 * 654183;
-   s4 -= s13 * 997805;
-   s5 += s13 * 136657;
-   s6 -= s13 * 683901;
-   s13 = 0;
-
-   s0 += s12 * 666643;
-   s1 += s12 * 470296;
-   s2 += s12 * 654183;
-   s3 -= s12 * 997805;
-   s4 += s12 * 136657;
-   s5 -= s12 * 683901;
-   s12 = 0;
+   redc_mul(s5, s6, s7, s8, s9, s10, s17);
+   redc_mul(s4, s5, s6, s7, s8, s9, s16);
+   redc_mul(s3, s4, s5, s6, s7, s8, s15);
+   redc_mul(s2, s3, s4, s5, s6, s7, s14);
+   redc_mul(s1, s2, s3, s4, s5, s6, s13);
+   redc_mul(s0, s1, s2, s3, s4, s5, s12);
 
    carry<21>(s0, s1);
    carry<21>(s2, s3);
@@ -174,13 +92,7 @@ void sc_reduce(uint8_t* s)
    carry<21>(s9, s10);
    carry<21>(s11, s12);
 
-   s0 += s12 * 666643;
-   s1 += s12 * 470296;
-   s2 += s12 * 654183;
-   s3 -= s12 * 997805;
-   s4 += s12 * 136657;
-   s5 -= s12 * 683901;
-   s12 = 0;
+   redc_mul(s0, s1, s2, s3, s4, s5, s12);
 
    carry<21>(s0, s1);
    carry<21>(s1, s2);
@@ -195,13 +107,7 @@ void sc_reduce(uint8_t* s)
    carry<21>(s10, s11);
    carry0<21>(s11, s12);
 
-   s0 += s12 * 666643;
-   s1 += s12 * 470296;
-   s2 += s12 * 654183;
-   s3 -= s12 * 997805;
-   s4 += s12 * 136657;
-   s5 -= s12 * 683901;
-   s12 = 0;
+   redc_mul(s0, s1, s2, s3, s4, s5, s12);
 
    carry0<21>(s0, s1);
    carry0<21>(s1, s2);