From e3718d7c03e6f4e092c0d9091bfe0350757eaf0b Mon Sep 17 00:00:00 2001
From: moneromooo-monero <moneromooo-monero@users.noreply.github.com>
Date: Sun, 24 Jun 2018 21:59:24 +0100
Subject: [PATCH] ringct: avoid repeated point conversion

---
 src/ringct/rctSigs.cpp | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/ringct/rctSigs.cpp b/src/ringct/rctSigs.cpp
index 01ac60fe6..1cb6438ea 100644
--- a/src/ringct/rctSigs.cpp
+++ b/src/ringct/rctSigs.cpp
@@ -637,10 +637,19 @@ namespace rct {
             keyV tmp(rows + 1);
             size_t i;
             keyM M(cols, tmp);
+            ge_p3 Cp3;
+            CHECK_AND_ASSERT_MES_L1(ge_frombytes_vartime(&Cp3, C.bytes) == 0, false, "point conv failed");
+            ge_cached Ccached;
+            ge_p3_to_cached(&Ccached, &Cp3);
+            ge_p1p1 p1;
             //create the matrix to mg sig
             for (i = 0; i < cols; i++) {
                     M[i][0] = pubs[i].dest;
-                    subKeys(M[i][1], pubs[i].mask, C);
+                    ge_p3 p3;
+                    CHECK_AND_ASSERT_MES_L1(ge_frombytes_vartime(&p3, pubs[i].mask.bytes) == 0, false, "point conv failed");
+                    ge_sub(&p1, &p3, &Ccached);
+                    ge_p1p1_to_p3(&p3, &p1);
+                    ge_p3_tobytes(M[i][1].bytes, &p3);
             }
             //DP(C);
             return MLSAG_Ver(message, M, mg, rows);