From 8ac2fb077dfcdf9a6fa78a871c494594dfa795b0 Mon Sep 17 00:00:00 2001
From: Rasmus Munk Larsen <rmlarsen@google.com>
Date: Wed, 2 Jul 2025 15:51:28 -0700
Subject: [PATCH] Use numext::fma for sparse x dense dot product.

---
 Eigen/src/SparseCore/SparseDot.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Eigen/src/SparseCore/SparseDot.h b/Eigen/src/SparseCore/SparseDot.h
index f040915b2..76a4f6cb7 100644
--- a/Eigen/src/SparseCore/SparseDot.h
+++ b/Eigen/src/SparseCore/SparseDot.h
@@ -36,10 +36,10 @@ inline typename internal::traits<Derived>::Scalar SparseMatrixBase<Derived>::dot
   Scalar res1(0);
   Scalar res2(0);
   for (; i; ++i) {
-    res1 += numext::conj(i.value()) * other.coeff(i.index());
+    res1 = numext::fma(numext::conj(i.value()), other.coeff(i.index()), res1);
     ++i;
     if (i) {
-      res2 += numext::conj(i.value()) * other.coeff(i.index());
+      res2 = numext::fma(numext::conj(i.value()), other.coeff(i.index()), res2);
     }
   }
   return res1 + res2;