Implement endomorphism optimization for secp256k1_ecmult_const

[secp256k1.git] / src / field_10x26.h

diff --git a/src/field_10x26.h b/src/field_10x26.h
index 1f855285e105004b0ac8f409b53a799dd603325e..cc4c74af3be02c22fe1b12e6f08697359f331970 100644 (file)
--- a/src/field_10x26.h
+++ b/src/field_10x26.h
@@ -18,17 +18,18 @@ typedef struct {
 #endif
 } secp256k1_fe_t;
 
+/* Unpacks a constant into a overlapping multi-limbed FE element. */
 #define SECP256K1_FE_CONST_INNER(d7, d6, d5, d4, d3, d2, d1, d0) { \
     (d0) & 0x3FFFFFFUL, \
-    ((d0) >> 26) | ((d1) & 0xFFFFFUL) << 6, \
-    ((d1) >> 20) | ((d2) & 0x3FFFUL) << 12, \
-    ((d2) >> 14) | ((d3) & 0xFFUL) << 18, \
-    ((d3) >> 8) | ((d4) & 0x3) << 24, \
-    ((d4) >> 2) & 0x3FFFFFFUL, \
-    ((d4) >> 28) | ((d5) & 0x3FFFFFUL) << 4, \
-    ((d5) >> 22) | ((d6) & 0xFFFF) << 10, \
-    ((d6) >> 16) | ((d7) & 0x3FF) << 16, \
-    ((d7) >> 10) \
+    (((uint32_t)d0) >> 26) | ((uint32_t)(d1) & 0xFFFFFUL) << 6, \
+    (((uint32_t)d1) >> 20) | ((uint32_t)(d2) & 0x3FFFUL) << 12, \
+    (((uint32_t)d2) >> 14) | ((uint32_t)(d3) & 0xFFUL) << 18, \
+    (((uint32_t)d3) >> 8) | ((uint32_t)(d4) & 0x3UL) << 24, \
+    (((uint32_t)d4) >> 2) & 0x3FFFFFFUL, \
+    (((uint32_t)d4) >> 28) | ((uint32_t)(d5) & 0x3FFFFFUL) << 4, \
+    (((uint32_t)d5) >> 22) | ((uint32_t)(d6) & 0xFFFFUL) << 10, \
+    (((uint32_t)d6) >> 16) | ((uint32_t)(d7) & 0x3FFUL) << 16, \
+    (((uint32_t)d7) >> 10) \
 }
 
 #ifdef VERIFY
@@ -42,5 +43,5 @@ typedef struct {
 } secp256k1_fe_storage_t;
 
 #define SECP256K1_FE_STORAGE_CONST(d7, d6, d5, d4, d3, d2, d1, d0) {{ (d0), (d1), (d2), (d3), (d4), (d5), (d6), (d7) }}
-
+#define SECP256K1_FE_STORAGE_CONST_GET(d) d.n[7], d.n[6], d.n[5], d.n[4],d.n[3], d.n[2], d.n[1], d.n[0]
 #endif