From 4ed8aa5c27e60a2c1a56e95dc6839cf4b5b90b77 Mon Sep 17 00:00:00 2001
From: Chris Duncan <chris@zoso.dev>
Date: Fri, 2 Oct 2026 02:57:51 -0700
Subject: [PATCH] Move remaining p scratch buffers except for tobytes.

---
 src/assembly/ed25519/ge.ts | 14 ++++++++------
 src/assembly/ed25519/p.ts  | 16 ++++++----------
 2 files changed, 14 insertions(+), 16 deletions(-)

diff --git a/src/assembly/ed25519/ge.ts b/src/assembly/ed25519/ge.ts
index bb3cd19..cfd0df1 100644
--- a/src/assembly/ed25519/ge.ts
+++ b/src/assembly/ed25519/ge.ts
@@ -264,6 +264,7 @@ const ge_scalarmult_base_tobytes_e: StaticArray<i8> = new StaticArray<i8>(64)
 const ge_scalarmult_base_tobytes_r: ge_p1p1 = new ge_p1p1()
 const ge_scalarmult_base_tobytes_s: ge_p2 = new ge_p2()
 const ge_scalarmult_base_tobytes_t: ge_precomp = new ge_precomp()
+const ge_scalarmult_base_tobytes_fe_scratch: FieldElement = fe()
 /**
  * `h = a * B` (with precomputation)
  *
@@ -287,6 +288,7 @@ export function ge_scalarmult_base_tobytes (S: StaticArray<u8>, a: StaticArray<u
 	const r = ge_scalarmult_base_tobytes_r
 	const s = ge_scalarmult_base_tobytes_s
 	const t = ge_scalarmult_base_tobytes_t
+	const fe_scratch = ge_scalarmult_base_tobytes_fe_scratch
 
 	for (let i = 0; i < 32; ++i) {
 		e[(i << 1) + 0] = (a[i] >> 0) & 15
@@ -314,13 +316,13 @@ export function ge_scalarmult_base_tobytes (S: StaticArray<u8>, a: StaticArray<u
 		ge_p1p1_to_p3(h, r)
 	}
 
-	ge_p3_dbl(r, h)
+	ge_p3_dbl(r, h, fe_scratch)
 	ge_p1p1_to_p2(s, r)
-	ge_p2_dbl(r, s)
+	ge_p2_dbl(r, s, fe_scratch)
 	ge_p1p1_to_p2(s, r)
-	ge_p2_dbl(r, s)
+	ge_p2_dbl(r, s, fe_scratch)
 	ge_p1p1_to_p2(s, r)
-	ge_p2_dbl(r, s)
+	ge_p2_dbl(r, s, fe_scratch)
 	ge_p1p1_to_p3(h, r)
 
 	// base pointer offset = 4 bytes * 12 values * 3 fe * 8 ge = 1152 bytes
@@ -381,7 +383,7 @@ export function ge_double_scalarmult_vartime_to_p3 (r: ge_p3, a: StaticArray<u8>
 
 	ge_p3_to_cached(Ai[0], A)
 
-	ge_p3_dbl(t, A)
+	ge_p3_dbl(t, A, fe_scratch)
 	ge_p1p1_to_p3(A2, t)
 
 	ge_add_cached(t, A2, Ai[0], fe_scratch)
@@ -421,7 +423,7 @@ export function ge_double_scalarmult_vartime_to_p3 (r: ge_p3, a: StaticArray<u8>
 	}
 
 	for (; i >= 0; --i) {
-		ge_p2_dbl(t, p)
+		ge_p2_dbl(t, p, fe_scratch)
 
 		if (aslide[i] > 0) {
 			ge_p1p1_to_p3(u, t)
diff --git a/src/assembly/ed25519/p.ts b/src/assembly/ed25519/p.ts
index 6cb144e..c9d9f6c 100644
--- a/src/assembly/ed25519/p.ts
+++ b/src/assembly/ed25519/p.ts
@@ -127,37 +127,33 @@ export function ge_p3_tobytes (s: StaticArray<u8>, h: ge_p3): void {
 	s[31] ^= fe_isnegative(x, fe_scratch_0) << 7
 }
 
-const ge_p2_dbl_t: FieldElement = fe()
 /**
  * r = 2 * p
  */
-export function ge_p2_dbl (r: ge_p1p1, p: ge_p2): void {
-	const t = ge_p2_dbl_t
+export function ge_p2_dbl (r: ge_p1p1, p: ge_p2, fe_scratch: FieldElement): void {
 	fe_sq(r.X, p.X)
 	fe_sq(r.Z, p.Y)
 	fe_sq2(r.T, p.Z)
 	fe_add(r.Y, p.X, p.Y)
-	fe_sq(t, r.Y)
+	fe_sq(fe_scratch, r.Y)
 	fe_add(r.Y, r.Z, r.X)
 	fe_sub(r.Z, r.Z, r.X)
-	fe_sub(r.X, t, r.Y)
+	fe_sub(r.X, fe_scratch, r.Y)
 	fe_sub(r.T, r.T, r.Z)
 }
 
-const ge_p3_dbl_t: FieldElement = fe()
 /**
  * r = 2 * p
  */
-export function ge_p3_dbl (r: ge_p1p1, p: ge_p3): void {
-	const t = ge_p3_dbl_t
+export function ge_p3_dbl (r: ge_p1p1, p: ge_p3, fe_scratch: FieldElement): void {
 	fe_sq(r.X, p.X)
 	fe_sq(r.Z, p.Y)
 	fe_sq2(r.T, p.Z)
 	fe_add(r.Y, p.X, p.Y)
-	fe_sq(t, r.Y)
+	fe_sq(fe_scratch, r.Y)
 	fe_add(r.Y, r.Z, r.X)
 	fe_sub(r.Z, r.Z, r.X)
-	fe_sub(r.X, t, r.Y)
+	fe_sub(r.X, fe_scratch, r.Y)
 	fe_sub(r.T, r.T, r.Z)
 }
 
-- 
2.52.0