From: Luke Kenneth Casson Leighton <lkcl@lkcl.net>
Date: Sun, 24 Apr 2022 19:27:27 +0000 (+0100)
Subject: use div/rem rather than re-calculate modulo from multiply
X-Git-Tag: opf_rfc_ls005_v1~2604
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=ea290b6acae3a820726c756a8f7de92035989e96;p=libreriscv.git

use div/rem rather than re-calculate modulo from multiply
---

diff --git a/openpower/sv/biginteger/divmnu64.c b/openpower/sv/biginteger/divmnu64.c
index b6c4b52e7..52e70a116 100644
--- a/openpower/sv/biginteger/divmnu64.c
+++ b/openpower/sv/biginteger/divmnu64.c
@@ -98,8 +98,9 @@ int divmnu(unsigned q[], unsigned r[], const unsigned u[], const unsigned v[],
         k = 0; // the case of a
         for (j = m - 1; j >= 0; j--)
         {                                 // single-digit
-            q[j] = (k * b + u[j]) / v[0]; // divisor here.
-            k = (k * b + u[j]) - q[j] * v[0];
+            uint64_t dig2 = (k * b + u[j]);
+            q[j] = dig2 / v[0]; // divisor here.
+            k = dig2 % v[0]; // modulo bak into next loop
         }
         if (r != NULL)
             r[0] = k;