From: Nicholas Clark <nick@ccl4.org>
Date: Mon, 20 Mar 2006 12:13:46 +0000 (+0000)
Subject: The two loops in Perl_utf8_distance can be merged.
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=eb63405fd7f24e5bad9ec7f42adce6af6314724e;p=p5sagit%2Fp5-mst-13.2.git

The two loops in Perl_utf8_distance can be merged.

p4raw-id: //depot/perl@27552
---

diff --git a/utf8.c b/utf8.c
index e5079cb..af63ac3 100644
--- a/utf8.c
+++ b/utf8.c
@@ -705,41 +705,37 @@ Perl_utf8_distance(pTHX_ const U8 *a, const U8 *b)
 {
     dVAR;
     IV off = 0;
+    IV sign = 1;
 
     /* Note: cannot use UTF8_IS_...() too eagerly here since  e.g.
      * the bitops (especially ~) can create illegal UTF-8.
      * In other words: in Perl UTF-8 is not just for Unicode. */
 
     if (a < b) {
-	while (a < b) {
-	    const U8 c = UTF8SKIP(a);
-	    if (b - a < c)
-		goto warn_and_return;
-	    a += c;
-	    off--;
-	}
+	const U8 *const temp = a;
+	a = b;
+	b = temp;
+	sign = -1;
     }
-    else {
-	while (b < a) {
-	    const U8 c = UTF8SKIP(b);
-
-	    if (a - b < c) {
-		warn_and_return:
-	        if (ckWARN_d(WARN_UTF8)) {
-		    if (PL_op)
-		        Perl_warner(aTHX_ packWARN(WARN_UTF8),
-				    "%s in %s", unees, OP_DESC(PL_op));
-		    else
-		        Perl_warner(aTHX_ packWARN(WARN_UTF8), unees);
-		}
-		return off;
+
+    while (b < a) {
+	const U8 c = UTF8SKIP(b);
+
+	if (a - b < c) {
+	    if (ckWARN_d(WARN_UTF8)) {
+		if (PL_op)
+		    Perl_warner(aTHX_ packWARN(WARN_UTF8),
+				"%s in %s", unees, OP_DESC(PL_op));
+		else
+		    Perl_warner(aTHX_ packWARN(WARN_UTF8), unees);
 	    }
-	    b += c;
-	    off++;
+	    return off * sign;
 	}
+	b += c;
+	off++;
     }
 
-    return off;
+    return off * sign;
 }
 
 /*