Make stripslashes() only dependent on SSE2 configuration. (#10408)

Alex Dowad noticed[1] that the SIMD stripslashes implementation actually
only depended on SSE2, and not on SSE4.2 instructions. Remove the
checking for SSE4.2 and only check for SSE2. This also greatly
simplifies the supporting code.

[1] #10313 (comment)

Author: nielsdos

ext/standard/string.c

@@ -48,6 +48,7 @@
 
 #ifdef __SSE2__
 #include <emmintrin.h>
+#include "Zend/zend_bitset.h"
 #endif
 
 /* this is read-only, so it's ok */
@@ -3472,15 +3473,10 @@ PHPAPI zend_string *php_addcslashes(zend_string *str, const char *what, size_t w
 ZEND_INTRIN_SSE4_2_FUNC_DECL(zend_string *php_addslashes_sse42(zend_string *str));
 zend_string *php_addslashes_default(zend_string *str);
 
-ZEND_INTRIN_SSE4_2_FUNC_DECL(void php_stripslashes_sse42(zend_string *str));
-void php_stripslashes_default(zend_string *str);
-
 # ifdef ZEND_INTRIN_SSE4_2_FUNC_PROTO
 PHPAPI zend_string *php_addslashes(zend_string *str) __attribute__((ifunc("resolve_addslashes")));
-PHPAPI void php_stripslashes(zend_string *str) __attribute__((ifunc("resolve_stripslashes")));
 
 typedef zend_string *(*php_addslashes_func_t)(zend_string *);
-typedef void (*php_stripslashes_func_t)(zend_string *);
 
 ZEND_NO_SANITIZE_ADDRESS
 ZEND_ATTRIBUTE_UNUSED /* clang mistakenly warns about this */
@@ -3490,36 +3486,21 @@ static php_addslashes_func_t resolve_addslashes(void) {
 	}
 	return php_addslashes_default;
 }
-
-ZEND_NO_SANITIZE_ADDRESS
-ZEND_ATTRIBUTE_UNUSED /* clang mistakenly warns about this */
-static php_stripslashes_func_t resolve_stripslashes(void) {
-	if (zend_cpu_supports_sse42()) {
-		return php_stripslashes_sse42;
-	}
-	return php_stripslashes_default;
-}
 # else /* ZEND_INTRIN_SSE4_2_FUNC_PTR */
 
 static zend_string *(*php_addslashes_ptr)(zend_string *str) = NULL;
-static void (*php_stripslashes_ptr)(zend_string *str) = NULL;
 
 PHPAPI zend_string *php_addslashes(zend_string *str) {
 	return php_addslashes_ptr(str);
 }
-PHPAPI void php_stripslashes(zend_string *str) {
-	php_stripslashes_ptr(str);
-}
 
 /* {{{ PHP_MINIT_FUNCTION */
 PHP_MINIT_FUNCTION(string_intrin)
 {
 	if (zend_cpu_supports_sse42()) {
 		php_addslashes_ptr = php_addslashes_sse42;
-		php_stripslashes_ptr = php_stripslashes_sse42;
 	} else {
 		php_addslashes_ptr = php_addslashes_default;
-		php_stripslashes_ptr = php_stripslashes_default;
 	}
 	return SUCCESS;
 }
@@ -3872,12 +3853,8 @@ static zend_always_inline char *php_stripslashes_impl(const char *str, char *out
 	return out;
 }
 
-#if defined(ZEND_INTRIN_SSE4_2_NATIVE) || defined(ZEND_INTRIN_SSE4_2_RESOLVER)
-# ifdef ZEND_INTRIN_SSE4_2_NATIVE
+#ifdef __SSE2__
 PHPAPI void php_stripslashes(zend_string *str)
-# elif defined(ZEND_INTRIN_SSE4_2_RESOLVER)
-void php_stripslashes_sse42(zend_string *str)
-# endif
 {
 	const char *s = ZSTR_VAL(str);
 	char *t = ZSTR_VAL(str);
@@ -3928,22 +3905,15 @@ void php_stripslashes_sse42(zend_string *str)
 		ZSTR_VAL(str)[ZSTR_LEN(str)] = '\0';
 	}
 }
-#endif
-
-#ifndef ZEND_INTRIN_SSE4_2_NATIVE
-# ifdef ZEND_INTRIN_SSE4_2_RESOLVER
-void php_stripslashes_default(zend_string *str) /* {{{ */
-# else
+#else
 PHPAPI void php_stripslashes(zend_string *str)
-# endif
 {
 	const char *t = php_stripslashes_impl(ZSTR_VAL(str), ZSTR_VAL(str), ZSTR_LEN(str));
 	if (t != (ZSTR_VAL(str) + ZSTR_LEN(str))) {
 		ZSTR_LEN(str) = t - ZSTR_VAL(str);
 		ZSTR_VAL(str)[ZSTR_LEN(str)] = '\0';
 	}
 }
-/* }}} */
 #endif
 /* }}} */