From 254d12215c3223b5820c1356dc12cd38eaa4cc37 Mon Sep 17 00:00:00 2001
From: matz <matz@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Mon, 20 Apr 2009 15:04:18 +0000
Subject: [PATCH] * string.c (rb_str_split_m): faster processing on 7bit
 strings.

* string.c (ascii_isspace): faster isspace() for 7bit strings.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@23234 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 ChangeLog |  6 ++++++
 string.c  | 62 +++++++++++++++++++++++++++++++++++++++++++++++--------
 2 files changed, 59 insertions(+), 9 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 4b5c52ca6d..3e95650053 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Mon Apr 20 20:29:04 2009  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* string.c (rb_str_split_m): faster processing on 7bit strings.
+
+	* string.c (ascii_isspace): faster isspace() for 7bit strings.
+
 Sun Apr 19 14:43:18 2009  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* eval.c (ruby_cleanup): the order of local variables on stack is
diff --git a/string.c b/string.c
index 7d96cdbc16..599b995795 100644
--- a/string.c
+++ b/string.c
@@ -5382,6 +5382,26 @@ rb_str_count(int argc, VALUE *argv, VALUE str)
     return INT2NUM(i);
 }
 
+static const char isspacetable[256] = {
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+};
+
+#define ascii_isspace(c) isspacetable[(unsigned char)(c)]
 
 /*
  *  call-seq:
@@ -5495,21 +5515,45 @@ rb_str_split_m(int argc, VALUE *argv, VALUE str)
 	unsigned int c;
 
 	end = beg;
-	while (ptr < eptr) {
-	    c = rb_enc_codepoint(ptr, eptr, enc);
-	    ptr += rb_enc_mbclen(ptr, eptr, enc);
-	    if (skip) {
-		if (rb_enc_isspace(c, enc)) {
+	if (is_ascii_string(str)) {
+	    while (ptr < eptr) {
+		c = (unsigned char)*ptr++;
+		if (skip) {
+		    if (ascii_isspace(c)) {
+			beg = ptr - bptr;
+		    }
+		    else {
+			end = ptr - bptr;
+			skip = 0;
+			if (!NIL_P(limit) && lim <= i) break;
+		    }
+		}
+		else if (ascii_isspace(c)) {
+		    rb_ary_push(result, rb_str_subseq(str, beg, end-beg));
+		    skip = 1;
 		    beg = ptr - bptr;
+		    if (!NIL_P(limit)) ++i;
 		}
 		else {
 		    end = ptr - bptr;
-		    skip = 0;
-		    if (!NIL_P(limit) && lim <= i) break;
 		}
 	    }
-	    else {
-		if (rb_enc_isspace(c, enc)) {
+	}
+	else {
+	    while (ptr < eptr) {
+		c = rb_enc_codepoint(ptr, eptr, enc);
+		ptr += rb_enc_mbclen(ptr, eptr, enc);
+		if (skip) {
+		    if (rb_enc_isspace(c, enc)) {
+			beg = ptr - bptr;
+		    }
+		    else {
+			end = ptr - bptr;
+			skip = 0;
+			if (!NIL_P(limit) && lim <= i) break;
+		    }
+		}
+		else if (rb_enc_isspace(c, enc)) {
 		    rb_ary_push(result, rb_str_subseq(str, beg, end-beg));
 		    skip = 1;
 		    beg = ptr - bptr;