From: Ondrej Zajicek <santiago@crfreenet.org>
Date: Fri, 8 Nov 2024 17:54:13 +0000 (+0100)
Subject: Lib: Optimized printing of numbers
X-Git-Tag: v2.16~28
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=49be4a0329b218a7c35c9275680de3ca177cd2e7;p=thirdparty%2Fbird.git

Lib: Optimized printing of numbers

One simple trick makes printing of numbers ~4x faster.
---

diff --git a/lib/printf.c b/lib/printf.c
index 424d545f9..68d3bb743 100644
--- a/lib/printf.c
+++ b/lib/printf.c
@@ -73,10 +73,25 @@ static char * number(char * str, u64 num, uint base, int size, int precision,
 	i = 0;
 	if (num == 0)
 		tmp[i++]='0';
-	else while (num != 0) {
-		uint res = num % base;
-		num = num / base;
-		tmp[i++] = digits[res];
+	else if (base == 10) {
+		/* Separate cases to have fixed divisors */
+		while (num != 0) {
+			uint res = num % 10;
+			num = num / 10;
+			tmp[i++] = digits[res];
+		}
+	} else if (base == 16) {
+		while (num != 0) {
+			uint res = num % 16;
+			num = num / 16;
+			tmp[i++] = digits[res];
+		}
+	} else {
+		while (num != 0) {
+			uint res = num % base;
+			num = num / base;
+			tmp[i++] = digits[res];
+		}
 	}
 	if (i > precision)
 		precision = i;