Add helper APIs for maybe-interned string creation

Add ZVAL_CHAR/RETVAL_CHAR/RETURN_CHAR as a shortcut for using
ZVAL_INTERNED_STRING and ZSTR_CHAR.

Add zend_string_init_fast() as a helper for the empty string /
one char interned string / zend_string_init() pattern.

Also add corresponding ZVAL_STRINGL_FAST etc macros.

Closes GH-5684.

10 files changed, 39 insertions, 77 deletions

diff --git a/ext/ffi/ffi.c b/ext/ffi/ffi.c
index e54f1dd8d4..20e1b67834 100644
--- a/ext/ffi/ffi.c
+++ b/ext/ffi/ffi.c
@@ -504,7 +504,7 @@ again:
 				ZVAL_BOOL(rv, *(uint8_t*)ptr);
 				return;
 			case ZEND_FFI_TYPE_CHAR:
-				ZVAL_INTERNED_STR(rv, ZSTR_CHAR(*(unsigned char*)ptr));
+				ZVAL_CHAR(rv, *(char*)ptr);
 				return;
 			case ZEND_FFI_TYPE_ENUM:
 				kind = type->enumeration.kind;
@@ -1077,7 +1077,7 @@ again:
 				ZVAL_BOOL(writeobj, *(uint8_t*)ptr);
 				break;
 			case ZEND_FFI_TYPE_CHAR:
-				ZVAL_INTERNED_STR(writeobj, ZSTR_CHAR(*(unsigned char*)ptr));
+				ZVAL_CHAR(writeobj, *(char*)ptr);
 				return SUCCESS;
 			case ZEND_FFI_TYPE_ENUM:
 				kind = ctype->enumeration.kind;
diff --git a/ext/mysqlnd/mysqlnd_wireprotocol.c b/ext/mysqlnd/mysqlnd_wireprotocol.c
index 7526c42ae6..71b11019d0 100644
--- a/ext/mysqlnd/mysqlnd_wireprotocol.c
+++ b/ext/mysqlnd/mysqlnd_wireprotocol.c
@@ -1666,12 +1666,8 @@ php_mysqlnd_rowp_read_text_protocol_aux(MYSQLND_ROW_BUFFER * row_buffer, zval *
 				} else if (Z_TYPE_P(current_field) == IS_STRING) {
 					/* nothing to do here, as we want a string and ps_fetch_from_1_to_8_bytes() has given us one */
 				}
-			} else if (len == 0) {
-				ZVAL_EMPTY_STRING(current_field);
-			} else if (len == 1) {
-				ZVAL_INTERNED_STR(current_field, ZSTR_CHAR((zend_uchar)*(char *)p));
 			} else {
-				ZVAL_STRINGL(current_field, (char *)p, len);
+				ZVAL_STRINGL_FAST(current_field, (char *)p, len);
 			}
 			p += len;
 		}
diff --git a/ext/opcache/Optimizer/sccp.c b/ext/opcache/Optimizer/sccp.c
index 1bec01c5e2..ac363eaddc 100644
--- a/ext/opcache/Optimizer/sccp.c
+++ b/ext/opcache/Optimizer/sccp.c
@@ -801,7 +801,7 @@ static inline int ct_eval_func_call(
 			}
 
 			c = Z_LVAL_P(args[0]) & 0xff;
-			ZVAL_INTERNED_STR(result, ZSTR_CHAR(c));
+			ZVAL_CHAR(result, c);
 			return SUCCESS;
 		} else if (zend_string_equals_literal(name, "count")) {
 			if (Z_TYPE_P(args[0]) != IS_ARRAY) {
diff --git a/ext/opcache/jit/zend_jit_helpers.c b/ext/opcache/jit/zend_jit_helpers.c
index 29f5d5f68e..7cc1e59322 100644
--- a/ext/opcache/jit/zend_jit_helpers.c
+++ b/ext/opcache/jit/zend_jit_helpers.c
@@ -638,7 +638,7 @@ try_string_offset:
 		real_offset = (UNEXPECTED(offset < 0)) /* Handle negative offset */
 			? (zend_long)Z_STRLEN_P(container) + offset : offset;
 		c = (zend_uchar)Z_STRVAL_P(container)[real_offset];
-		ZVAL_INTERNED_STR(result, ZSTR_CHAR(c));
+		ZVAL_CHAR(result, c);
 	}
 }
 
@@ -685,7 +685,7 @@ try_string_offset:
 		real_offset = (UNEXPECTED(offset < 0)) /* Handle negative offset */
 			? (zend_long)Z_STRLEN_P(container) + offset : offset;
 		c = (zend_uchar)Z_STRVAL_P(container)[real_offset];
-		ZVAL_INTERNED_STR(result, ZSTR_CHAR(c));
+		ZVAL_CHAR(result, c);
 	}
 }
 
@@ -952,7 +952,7 @@ static zend_never_inline void zend_assign_to_string_offset(zval *str, zval *dim,
 
 	if (result) {
 		/* Return the new character */
-		ZVAL_INTERNED_STR(result, ZSTR_CHAR(c));
+		ZVAL_CHAR(result, c);
 	}
 }
 
diff --git a/ext/pcre/php_pcre.c b/ext/pcre/php_pcre.c
index 55f9d2db7b..2ed5d9d7dd 100644
--- a/ext/pcre/php_pcre.c
+++ b/ext/pcre/php_pcre.c
@@ -966,13 +966,7 @@ static void init_unmatched_empty_pair() {
 
 static zend_always_inline void populate_match_value_str(
 		zval *val, const char *subject, PCRE2_SIZE start_offset, PCRE2_SIZE end_offset) {
-	if (start_offset == end_offset) {
-		ZVAL_EMPTY_STRING(val);
-	} else if (start_offset + 1 == end_offset) {
-		ZVAL_INTERNED_STR(val, ZSTR_CHAR((unsigned char) subject[start_offset]));
-	} else {
-		ZVAL_STRINGL(val, subject + start_offset, end_offset - start_offset);
-	}
+	ZVAL_STRINGL_FAST(val, subject + start_offset, end_offset - start_offset);
 }
 
 static inline void populate_match_value(
diff --git a/ext/standard/array.c b/ext/standard/array.c
index eda7ef589c..d942cfc184 100644
--- a/ext/standard/array.c
+++ b/ext/standard/array.c
@@ -2739,7 +2739,7 @@ PHP_FUNCTION(range)
 			} ZEND_HASH_FILL_END();
 		} else {
 			array_init(return_value);
-			ZVAL_INTERNED_STR(&tmp, ZSTR_CHAR(low));
+			ZVAL_CHAR(&tmp, low);
 			zend_hash_next_index_insert_new(Z_ARRVAL_P(return_value), &tmp);
 		}
 	} else if (Z_TYPE_P(zlow) == IS_DOUBLE || Z_TYPE_P(zhigh) == IS_DOUBLE || is_step_double) {
diff --git a/ext/standard/basic_functions.c b/ext/standard/basic_functions.c
index 883b5d45c5..056bc0ac37 100755
--- a/ext/standard/basic_functions.c
+++ b/ext/standard/basic_functions.c
@@ -2041,6 +2041,21 @@ PHP_FUNCTION(highlight_string)
 }
 /* }}} */
 
+#define INI_RETVAL_STR(val) do { \
+	/* copy to return value here, because alter might free it! */ \
+	if (ZSTR_IS_INTERNED(val)) { \
+		RETVAL_INTERNED_STR(val); \
+	} else if (ZSTR_LEN(val) == 0) { \
+		RETVAL_EMPTY_STRING(); \
+	} else if (ZSTR_LEN(val) == 1) { \
+		RETVAL_CHAR(ZSTR_VAL(val)[0]); \
+	} else if (!(GC_FLAGS(val) & GC_PERSISTENT)) { \
+		ZVAL_NEW_STR(return_value, zend_string_copy(val)); \
+	} else { \
+		ZVAL_NEW_STR(return_value, zend_string_init(ZSTR_VAL(val), ZSTR_LEN(val), 0)); \
+	} \
+} while (0)
+
 /* {{{ proto string|false ini_get(string varname)
    Get a configuration option */
 PHP_FUNCTION(ini_get)
@@ -2057,17 +2072,7 @@ PHP_FUNCTION(ini_get)
 		RETURN_FALSE;
 	}
 
-	if (ZSTR_IS_INTERNED(val)) {
-		RETVAL_INTERNED_STR(val);
-	} else if (ZSTR_LEN(val) == 0) {
-		RETVAL_EMPTY_STRING();
-	} else if (ZSTR_LEN(val) == 1) {
-		RETVAL_INTERNED_STR(ZSTR_CHAR((zend_uchar)ZSTR_VAL(val)[0]));
-	} else if (!(GC_FLAGS(val) & GC_PERSISTENT)) {
-		ZVAL_NEW_STR(return_value, zend_string_copy(val));
-	} else {
-		ZVAL_NEW_STR(return_value, zend_string_init(ZSTR_VAL(val), ZSTR_LEN(val), 0));
-	}
+	INI_RETVAL_STR(val);
 }
 /* }}} */
 
@@ -2168,19 +2173,8 @@ PHP_FUNCTION(ini_set)
 
 	val = zend_ini_get_value(varname);
 
-	/* copy to return here, because alter might free it! */
 	if (val) {
-		if (ZSTR_IS_INTERNED(val)) {
-			RETVAL_INTERNED_STR(val);
-		} else if (ZSTR_LEN(val) == 0) {
-			RETVAL_EMPTY_STRING();
-		} else if (ZSTR_LEN(val) == 1) {
-			RETVAL_INTERNED_STR(ZSTR_CHAR((zend_uchar)ZSTR_VAL(val)[0]));
-		} else if (!(GC_FLAGS(val) & GC_PERSISTENT)) {
-			ZVAL_NEW_STR(return_value, zend_string_copy(val));
-		} else {
-			ZVAL_NEW_STR(return_value, zend_string_init(ZSTR_VAL(val), ZSTR_LEN(val), 0));
-		}
+		INI_RETVAL_STR(val);
 	} else {
 		RETVAL_FALSE;
 	}
@@ -2209,6 +2203,8 @@ PHP_FUNCTION(ini_set)
 }
 /* }}} */
 
+#undef INI_RETVAL_STR
+
 /* {{{ proto void ini_restore(string varname)
    Restore the value of a configuration option specified by varname */
 PHP_FUNCTION(ini_restore)
diff --git a/ext/standard/string.c b/ext/standard/string.c
index 635f5daf8f..8a8c889f08 100644
--- a/ext/standard/string.c
+++ b/ext/standard/string.c
@@ -1063,15 +1063,7 @@ PHPAPI void php_explode(const zend_string *delim, zend_string *str, zval *return
 		zend_hash_next_index_insert_new(Z_ARRVAL_P(return_value), &tmp);
 	} else {
 		do {
-			size_t l = p2 - p1;
-
-			if (l == 0) {
-				ZVAL_EMPTY_STRING(&tmp);
-			} else if (l == 1) {
-				ZVAL_INTERNED_STR(&tmp, ZSTR_CHAR((zend_uchar)(*p1)));
-			} else {
-				ZVAL_STRINGL(&tmp, p1, p2 - p1);
-			}
+			ZVAL_STRINGL_FAST(&tmp, p1, p2 - p1);
 			zend_hash_next_index_insert_new(Z_ARRVAL_P(return_value), &tmp);
 			p1 = p2 + ZSTR_LEN(delim);
 			p2 = php_memnstr(p1, ZSTR_VAL(delim), ZSTR_LEN(delim), endp);
@@ -2286,15 +2278,11 @@ truncate_len:
 		l = (zend_long)ZSTR_LEN(str) - f;
 	}
 
-	if (l == 0) {
-		RETURN_EMPTY_STRING();
-	} else if (l == 1) {
-		RETURN_INTERNED_STR(ZSTR_CHAR((zend_uchar)(ZSTR_VAL(str)[f])));
-	} else if (l == ZSTR_LEN(str)) {
+	if (l == ZSTR_LEN(str)) {
 		RETURN_STR_COPY(str);
+	} else {
+		RETURN_STRINGL_FAST(ZSTR_VAL(str) + f, l);
 	}
-
-	RETURN_STRINGL(ZSTR_VAL(str) + f, l);
 }
 /* }}} */
 
@@ -2629,7 +2617,7 @@ PHP_FUNCTION(chr)
 	ZEND_PARSE_PARAMETERS_END();
 
 	c &= 0xff;
-	ZVAL_INTERNED_STR(return_value, ZSTR_CHAR(c));
+	RETURN_CHAR(c);
 }
 /* }}} */
 
@@ -3040,9 +3028,9 @@ static zend_string* php_char_to_str_ex(zend_string *str, char from, char *to, si
 static zend_string *php_str_to_str_ex(zend_string *haystack,
 	const char *needle, size_t needle_len, const char *str, size_t str_len, zend_long *replace_count)
 {
-	zend_string *new_str;
 
 	if (needle_len < ZSTR_LEN(haystack)) {
+		zend_string *new_str;
 		const char *end;
 		const char *p, *r;
 		char *e;
@@ -3103,16 +3091,8 @@ static zend_string *php_str_to_str_ex(zend_string *haystack,
 nothing_todo:
 		return zend_string_copy(haystack);
 	} else {
-		if (str_len == 0) {
-			new_str = ZSTR_EMPTY_ALLOC();
-		} else if (str_len == 1) {
-			new_str = ZSTR_CHAR((zend_uchar)(*str));
-		} else {
-			new_str = zend_string_init(str, str_len, 0);
-		}
-
 		(*replace_count)++;
-		return new_str;
+		return zend_string_init_fast(str, str_len);
 	}
 }
 /* }}} */
@@ -4805,7 +4785,7 @@ PHP_FUNCTION(setlocale)
 						/* C locale is represented as NULL. */
 						BG(ctype_string) = NULL;
 						zend_string_release_ex(loc, 0);
-						RETURN_INTERNED_STR(ZSTR_CHAR('C'));
+						RETURN_CHAR('C');
 					} else if (len == ZSTR_LEN(loc) && !memcmp(ZSTR_VAL(loc), retval, len)) {
 						BG(ctype_string) = zend_string_copy(loc);
 						RETURN_STR(BG(ctype_string));
diff --git a/ext/standard/var_unserializer.re b/ext/standard/var_unserializer.re
index c395f3cb5c..8766b3f2f1 100644
--- a/ext/standard/var_unserializer.re
+++ b/ext/standard/var_unserializer.re
@@ -943,14 +943,10 @@ use_double:
 	YYCURSOR += 2;
 	*p = YYCURSOR;
 
-	if (len == 0) {
-		ZVAL_EMPTY_STRING(rval);
-	} else if (len == 1) {
-		ZVAL_INTERNED_STR(rval, ZSTR_CHAR((zend_uchar)*str));
-	} else if (as_key) {
+	if (as_key) {
 		ZVAL_STR(rval, zend_string_init_interned(str, len, 0));
 	} else {
-		ZVAL_STRINGL(rval, str, len);
+		ZVAL_STRINGL_FAST(rval, str, len);
 	}
 	return 1;
 }
diff --git a/ext/tokenizer/tokenizer.c b/ext/tokenizer/tokenizer.c
index 901e609d2d..866977397d 100644
--- a/ext/tokenizer/tokenizer.c
+++ b/ext/tokenizer/tokenizer.c
@@ -226,7 +226,7 @@ PHP_METHOD(PhpToken, getTokenName)
 	}
 
 	if (Z_LVAL_P(id_zval) < 256) {
-		RETURN_INTERNED_STR(ZSTR_CHAR(Z_LVAL_P(id_zval)));
+		RETURN_CHAR(Z_LVAL_P(id_zval));
 	} else {
 		const char *token_name = get_token_type_name(Z_LVAL_P(id_zval));
 		if (!token_name) {