Make stripos optimization linear

Author: iluuu1994

Zend/zend_operators.h

@@ -919,7 +919,7 @@ static zend_always_inline void zend_unwrap_reference(zval *op) /* {{{ */
 }
 /* }}} */
 
-static zend_always_inline const char *strnichr(const char *ptr, char value, size_t num)
+static zend_always_inline const char *zend_strnichr(const char *ptr, char value, size_t num)
 {
 	char value_lower = zend_tolower_ascii(value);
 	char value_upper = zend_toupper_ascii(value);
@@ -936,7 +936,7 @@ static zend_always_inline const char *strnichr(const char *ptr, char value, size
 	return ptr_lower ? ptr_lower : ptr_upper;
 }
 
-static zend_always_inline bool strnieq(const char *ptr1, const char *ptr2, size_t num)
+static zend_always_inline bool zend_strnieq(const char *ptr1, const char *ptr2, size_t num)
 {
 	for (size_t i = 0; i < num; i++) {
 		if (zend_tolower_ascii(*ptr1++) != zend_tolower_ascii(*ptr2++)) {
@@ -955,7 +955,7 @@ zend_memnistr(const char *haystack, const char *needle, size_t needle_len, const
 	ZEND_ASSERT(end >= p);
 
 	if (needle_len == 1) {
-		return (const char *)strnichr(p, *needle, (end-p));
+		return (const char *)zend_strnichr(p, *needle, (end-p));
 	} else if (UNEXPECTED(needle_len == 0)) {
 		return p;
 	}
@@ -966,18 +966,46 @@ zend_memnistr(const char *haystack, const char *needle, size_t needle_len, const
 		return NULL;
 	}
 
+	const char ns_upper = zend_tolower_ascii(*needle);
+	const char ns_lower = zend_toupper_ascii(*needle);
 	const char ne = zend_tolower_ascii(needle[needle_len-1]);
 	end -= needle_len;
 
-	while (p <= end) {
-		if ((p = (const char *)strnichr(p, *needle, (end-p+1)))) {
-			if (ne == zend_tolower_ascii(p[needle_len-1]) && strnieq(needle+1, p+1, needle_len-2)) {
+	if (ns_upper == ns_lower) {
+		while (p <= end) {
+			if ((p = (const char *)memchr(p, ns_lower, (end-p+1)))) {
+				if (ne == zend_tolower_ascii(p[needle_len-1]) && zend_strnieq(needle+1, p+1, needle_len-2)) {
+					return p;
+				}
+			} else {
+				return NULL;
+			}
+			p++;
+		}
+	} else {
+		const char *next_lower = (const char *)memchr(p, ns_lower, (end-p+1));
+		const char *next_upper = (const char *)memchr(p, ns_upper, (end-p+1));
+		while (p <= end) {
+			if (next_lower && (!next_upper || next_lower < next_upper)) {
+				p = next_lower;
+				next_lower = NULL;
+			} else if (next_upper) {
+				p = next_upper;
+				next_upper = NULL;
+			} else {
+				return NULL;
+			}
+			if (ne == zend_tolower_ascii(p[needle_len-1]) && zend_strnieq(needle+1, p+1, needle_len-2)) {
 				return p;
 			}
-		} else {
-			return NULL;
+			p++;
+			if (!next_lower) {
+				next_lower = (const char *)memchr(p, ns_lower, (end-p+1));
+			}
+			if (!next_upper) {
+				next_upper = (const char *)memchr(p, ns_upper, (end-p+1));
+			}
 		}
-		p++;
 	}
 
 	return NULL;