Jit Attribute support

Remove the obsolete doc-comment based JIT trigger. Since function and
tracing JITs are recommended for now, the attribute based trigger mode
is removed for now.

Only @@jit("off") is available to disable the JIT for a function/method.

Author: beberlei

ext/opcache/jit/zend_jit.c

@@ -23,6 +23,7 @@
 #include "Zend/zend_exceptions.h"
 #include "Zend/zend_constants.h"
 #include "Zend/zend_ini.h"
+#include "Zend/zend_attributes.h"
 #include "zend_smart_str.h"
 #include "jit/zend_jit.h"
 
@@ -3384,28 +3385,29 @@ static int zend_jit_setup_hot_counters(zend_op_array *op_array)
 	return SUCCESS;
 }
 
-static int zend_needs_manual_jit(const zend_op_array *op_array)
+static int zend_jit_disabled(const zend_op_array *op_array)
 {
-	if (op_array->doc_comment) {
-		const char *s = ZSTR_VAL(op_array->doc_comment);
-		const char *p = strstr(s, "@jit");
+	zend_attribute *jit = zend_get_attribute_str(op_array->attributes, "jit", sizeof("jit")-1);
 
-		if (p) {
-			size_t l = ZSTR_LEN(op_array->doc_comment);
+	if (jit == NULL || jit->argc == 0) {
+		return 0;
+	}
 
-			if ((p == s + 3 || *(p-1) <= ' ') &&
-			    (p + 6 == s + l || *(p+4) <= ' ')) {
-				return 1;
-			}
-		}
+	if (zend_string_equals_literal_ci(Z_STR(jit->args[0].value), "off")) {
+		return 1;
 	}
+
 	return 0;
 }
 
 #include "jit/zend_jit_trace.c"
 
 ZEND_EXT_API int zend_jit_op_array(zend_op_array *op_array, zend_script *script)
 {
+	if (zend_jit_disabled(op_array)) {
+		return SUCCESS;
+	}
+
 	if (dasm_ptr == NULL) {
 		return FAILURE;
 	}
@@ -3455,12 +3457,6 @@ ZEND_EXT_API int zend_jit_op_array(zend_op_array *op_array, zend_script *script)
 		return zend_jit_setup_hot_trace_counters(op_array);
 	} else if (JIT_G(trigger) == ZEND_JIT_ON_SCRIPT_LOAD) {
 		return zend_real_jit_func(op_array, script, NULL);
-	} else if (JIT_G(trigger) == ZEND_JIT_ON_DOC_COMMENT) {
-		if (zend_needs_manual_jit(op_array)) {
-			return zend_real_jit_func(op_array, script, NULL);
-		} else {
-			return SUCCESS;
-		}
 	} else {
 		ZEND_UNREACHABLE();
 	}
@@ -3495,21 +3491,19 @@ ZEND_EXT_API int zend_jit_script(zend_script *script)
 				goto jit_failure;
 			}
 		}
-	} else if (JIT_G(trigger) == ZEND_JIT_ON_SCRIPT_LOAD ||
-	           JIT_G(trigger) == ZEND_JIT_ON_DOC_COMMENT) {
+	} else if (JIT_G(trigger) == ZEND_JIT_ON_SCRIPT_LOAD) {
+		int do_jit = 1;
 
-		if (JIT_G(trigger) == ZEND_JIT_ON_DOC_COMMENT) {
-			int do_jit = 0;
-			for (i = 0; i < call_graph.op_arrays_count; i++) {
-				if (zend_needs_manual_jit(call_graph.op_arrays[i])) {
-					do_jit = 1;
-					break;
-				}
-			}
-			if (!do_jit) {
-				goto jit_failure;
+		for (i = 0; i < call_graph.op_arrays_count; i++) {
+			if (zend_jit_disabled(call_graph.op_arrays[i])) {
+				do_jit = 0;
+				break;
 			}
 		}
+		if (!do_jit) {
+			goto jit_failure;
+		}
+
 		for (i = 0; i < call_graph.op_arrays_count; i++) {
 			info = ZEND_FUNC_INFO(call_graph.op_arrays[i]);
 			if (info) {
@@ -3531,10 +3525,6 @@ ZEND_EXT_API int zend_jit_script(zend_script *script)
 		}
 
 		for (i = 0; i < call_graph.op_arrays_count; i++) {
-			if (JIT_G(trigger) == ZEND_JIT_ON_DOC_COMMENT &&
-			    !zend_needs_manual_jit(call_graph.op_arrays[i])) {
-				continue;
-			}
 			info = ZEND_FUNC_INFO(call_graph.op_arrays[i]);
 			if (info) {
 				if (zend_jit_op_array_analyze2(call_graph.op_arrays[i], script, &info->ssa, ZCG(accel_directives).optimization_level) != SUCCESS) {
@@ -3546,10 +3536,6 @@ ZEND_EXT_API int zend_jit_script(zend_script *script)
 
 		if (JIT_G(debug) & ZEND_JIT_DEBUG_SSA) {
 			for (i = 0; i < call_graph.op_arrays_count; i++) {
-				if (JIT_G(trigger) == ZEND_JIT_ON_DOC_COMMENT &&
-				    !zend_needs_manual_jit(call_graph.op_arrays[i])) {
-					continue;
-				}
 				info = ZEND_FUNC_INFO(call_graph.op_arrays[i]);
 				if (info) {
 					zend_dump_op_array(call_graph.op_arrays[i], ZEND_DUMP_HIDE_UNREACHABLE|ZEND_DUMP_RC_INFERENCE|ZEND_DUMP_SSA, "JIT", &info->ssa);
@@ -3558,10 +3544,6 @@ ZEND_EXT_API int zend_jit_script(zend_script *script)
 		}
 
 		for (i = 0; i < call_graph.op_arrays_count; i++) {
-			if (JIT_G(trigger) == ZEND_JIT_ON_DOC_COMMENT &&
-			    !zend_needs_manual_jit(call_graph.op_arrays[i])) {
-				continue;
-			}
 			info = ZEND_FUNC_INFO(call_graph.op_arrays[i]);
 			if (info) {
 				if (zend_jit(call_graph.op_arrays[i], &info->ssa, NULL) != SUCCESS) {
@@ -3602,8 +3584,7 @@ ZEND_EXT_API int zend_jit_script(zend_script *script)
 	return SUCCESS;
 
 jit_failure:
-	if (JIT_G(trigger) == ZEND_JIT_ON_SCRIPT_LOAD ||
-	    JIT_G(trigger) == ZEND_JIT_ON_DOC_COMMENT) {
+	if (JIT_G(trigger) == ZEND_JIT_ON_SCRIPT_LOAD) {
 		for (i = 0; i < call_graph.op_arrays_count; i++) {
 			ZEND_SET_FUNC_INFO(call_graph.op_arrays[i], NULL);
 		}
@@ -3716,6 +3697,7 @@ static int zend_jit_parse_config_num(zend_long jit)
 
 	jit /= 10;
 	if (jit % 10 > 5) return FAILURE;
+	if (jit % 10 == 4) return FAILURE;
 	JIT_G(trigger) = jit % 10;
 
 	jit /= 10;

ext/opcache/jit/zend_jit.h

@@ -28,9 +28,9 @@
 
 #define ZEND_JIT_ON_SCRIPT_LOAD    0
 #define ZEND_JIT_ON_FIRST_EXEC     1
-#define ZEND_JIT_ON_PROF_REQUEST   2     /* compile the most frequently caled on first request functions */
+#define ZEND_JIT_ON_PROF_REQUEST   2     /* compile the most frequently called on first request functions */
 #define ZEND_JIT_ON_HOT_COUNTERS   3     /* compile functions after N calls or loop iterations */
-#define ZEND_JIT_ON_DOC_COMMENT    4     /* compile functions with "@jit" tag in doc-comments */
+#define ZEND_JIT_ON_ATTRIBUTE      4     /* compile functions with @@Jit attribute, unused at the moment */
 #define ZEND_JIT_ON_HOT_TRACE      5     /* trace functions after N calls or loop iterations */
 
 #define ZEND_JIT_REG_ALLOC_LOCAL  (1<<0) /* local linear scan register allocation */
@@ -176,4 +176,6 @@ struct _zend_lifetime_interval {
 	zend_lifetime_interval *list_next;
 };
 
+zend_class_entry *zend_ce_opcache_jit_attribute;
+
 #endif /* HAVE_JIT_H */

ext/opcache/tests/jit/attributes_001.phpt

@@ -0,0 +1,22 @@
+--TEST--
+JIT disabled with attributes, assert no jit debug output
+--INI--
+opcache.enable=1
+opcache.enable_cli=1
+opcache.file_update_protection=0
+opcache.jit_buffer_size=1M
+opcache.jit=1205
+opcache.jit_debug=1
+opcache.protect_memory=1
+--SKIPIF--
+<?php require_once('skipif.inc'); ?>
+--FILE--
+<?php
+@@Jit("off")
+function foo($a) {
+    return $a * $a;
+}
+?>
+okey
+--EXPECT--
+okey

ext/opcache/tests/jit/attributes_002.phpt

@@ -0,0 +1,21 @@
+--TEST--
+JIT trigger with attributes
+--INI--
+opcache.enable=1
+opcache.enable_cli=1
+opcache.file_update_protection=0
+opcache.jit_buffer_size=1M
+opcache.jit=1205
+opcache.jit_debug=1
+opcache.protect_memory=1
+--SKIPIF--
+<?php require_once('skipif.inc'); ?>
+--FILE--
+<?php
+@@Jit("something else")
+function foo($a) {
+    return $a * $a;
+}
+?>
+--EXPECTF--
+Fatal error: @@Jit argument $mode only supports the value 'off' %s

ext/opcache/zend_accelerator_module.c

@@ -31,6 +31,7 @@
 #include "zend_virtual_cwd.h"
 #include "ext/standard/info.h"
 #include "ext/standard/php_filestat.h"
+#include "Zend/zend_attributes.h"
 #include "opcache_arginfo.h"
 
 #if HAVE_JIT
@@ -370,12 +371,55 @@ static ZEND_NAMED_FUNCTION(accel_is_readable)
 	}
 }
 
+#if HAVE_JIT
+static void zend_jit_validate_opcache_attribute(zend_attribute *jit, uint32_t target, zend_class_entry *scope)
+{
+	if (jit->argc == 0) {
+		zend_error(E_COMPILE_ERROR, "Too few arguments to attribute @@Jit, %d passed and exactly 1 expected", jit->argc);
+	}
+
+	if (jit->argc > 1) {
+		zend_error(E_COMPILE_ERROR, "Too many arguments to attribute @@Jit, %d passed and exactly 1 expected", jit->argc);
+	}
+
+	if (jit->argc == 1) {
+		zend_string *trigger;
+
+		if (Z_TYPE(jit->args[0].value) != IS_STRING) {
+			zend_error(E_COMPILE_ERROR, "@@Jit argument $mode must be a string");
+		}
+
+		trigger = Z_STR(jit->args[0].value);
+
+		if (!zend_string_equals_literal_ci(trigger, "off")) {
+			zend_error(E_COMPILE_ERROR, "@@Jit argument $mode only supports the value 'off'");
+		}
+	}
+}
+#endif
+
 static ZEND_MINIT_FUNCTION(zend_accelerator)
 {
 	(void)type; /* keep the compiler happy */
+#if HAVE_JIT
+	zend_class_entry ce;
+	zend_internal_attribute *attr;
+#endif
 
 	REGISTER_INI_ENTRIES();
 
+#if HAVE_JIT
+	INIT_CLASS_ENTRY(ce, "Jit", NULL);
+	zend_ce_opcache_jit_attribute = zend_register_internal_class(&ce);
+	zend_ce_opcache_jit_attribute->ce_flags |= ZEND_ACC_FINAL;
+
+	attr = zend_internal_attribute_register(
+		zend_ce_opcache_jit_attribute,
+		ZEND_ATTRIBUTE_TARGET_FUNCTION | ZEND_ATTRIBUTE_TARGET_METHOD
+	);
+	attr->validator = zend_jit_validate_opcache_attribute;
+#endif
+
 	return SUCCESS;
 }