From 572d87e3cac465b9bd31e584eecdf3ceb7e0ba6d Mon Sep 17 00:00:00 2001
From: Borislav Stanimirov <b.stanimirov@abv.bg>
Date: Sat, 13 Feb 2021 00:54:53 +0200
Subject: [PATCH] <charconv>: Optimize _Integer_to_chars for bases 3,5,6,7,9
 (#1622)

---
 stl/inc/charconv | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/stl/inc/charconv b/stl/inc/charconv
index 20d8342c4..9ab5d01ec 100644
--- a/stl/inc/charconv
+++ b/stl/inc/charconv
@@ -127,6 +127,17 @@ _NODISCARD to_chars_result _Integer_to_chars(
         } while (_Value != 0);
         break;
 
+    case 3:
+    case 5:
+    case 6:
+    case 7:
+    case 9:
+        do {
+            *--_RNext = static_cast<char>('0' + _Value % _Base);
+            _Value    = static_cast<_Unsigned>(_Value / _Base);
+        } while (_Value != 0);
+        break;
+
     default:
         do {
             *--_RNext = _Charconv_digits[_Value % _Base];