From: Luke Kenneth Casson Leighton <lkcl@lkcl.net>
Date: Tue, 26 Apr 2022 14:26:22 +0000 (+0100)
Subject: big leftshift split out
X-Git-Tag: opf_rfc_ls005_v1~2581
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=e6b88df741ff14e5c4fc5e9bdcae967e9a93d8df;p=libreriscv.git

big leftshift split out
---

diff --git a/openpower/sv/biginteger/divgnu64.c b/openpower/sv/biginteger/divgnu64.c
index 483f099a5..18e765e6d 100644
--- a/openpower/sv/biginteger/divgnu64.c
+++ b/openpower/sv/biginteger/divgnu64.c
@@ -63,6 +63,13 @@ void bigrsh(unsigned s, unsigned r[], unsigned un[], int n)
     r[n - 1] = un[n - 1] >> s;
 }
 
+void biglsh(unsigned s, unsigned vn[], unsigned const v[], int n)
+{
+    for (int i = n - 1; i > 0; i--)
+        vn[i] = (v[i] << s) | ((unsigned long long)v[i - 1] >> (32 - s));
+    vn[0] = v[0] << s;
+}
+
 bool bigmul(unsigned long long qhat, unsigned product[], unsigned vn[], int m,
             int n)
 {
@@ -177,15 +184,11 @@ int divmnu(unsigned q[], unsigned r[], const unsigned u[], const unsigned v[],
 
     s = nlz(v[n - 1]); // 0 <= s <= 31.
     vn = (unsigned *)alloca(4 * n);
-    for (i = n - 1; i > 0; i--)
-        vn[i] = (v[i] << s) | ((unsigned long long)v[i - 1] >> (32 - s));
-    vn[0] = v[0] << s;
+    biglsh(s, vn, v, n);
 
     un = (unsigned *)alloca(4 * (m + 1));
     un[m] = (unsigned long long)u[m - 1] >> (32 - s);
-    for (i = m - 1; i > 0; i--)
-        un[i] = (u[i] << s) | ((unsigned long long)u[i - 1] >> (32 - s));
-    un[0] = u[0] << s;
+    biglsh(s, un, u, m);
 
     for (j = m - n; j >= 0; j--)
     { // Main loop.