php版本 PHP 5.3.14
1. ==(调用is_equal_function->compare_function ),!=(调用is_not_equal_function->compare_function)
<?php
$i = 1;
$j = 1.0;
echo $i == $j;//opcode
line # * op fetch ext return operands
---------------------------------------------------------------------------------
3 0 > ASSIGN !0, 1
4 1 ASSIGN !1, 1
6 2 IS_EQUAL ~2 !0, !1
3 ECHO ~2
7 4 > RETURN 1
调用Zend/zend_operators.c is_equal_function
if (compare_function(result, op1, op2 TSRMLS_CC) == FAILURE) {
return FAILURE;
}
ZVAL_BOOL(result, (Z_LVAL_P(result) == 0));
return SUCCESS;//compare_function，比较两个zval,op1,op2,结果记录到result，
switch (TYPE_PAIR(Z_TYPE_P(op1), Z_TYPE_P(op2))) {
case TYPE_PAIR(IS_LONG, IS_LONG)://两个整形比较
ZVAL_LONG(result, Z_LVAL_P(op1)>Z_LVAL_P(op2)?1:(Z_LVAL_P(op1)<Z_LVAL_P(op2)?-1:0));
return SUCCESS;
case TYPE_PAIR(IS_DOUBLE, IS_LONG)://一个double，一个整形，会将整形转化为double，相减，
Z_DVAL_P(result) = Z_DVAL_P(op1) - (double)Z_LVAL_P(op2);
ZVAL_LONG(result, ZEND_NORMALIZE_BOOL(Z_DVAL_P(result)));
return SUCCESS;
case TYPE_PAIR(IS_LONG, IS_DOUBLE)://同上，
Z_DVAL_P(result) = (double)Z_LVAL_P(op1) - Z_DVAL_P(op2);
ZVAL_LONG(result, ZEND_NORMALIZE_BOOL(Z_DVAL_P(result)));
return SUCCESS;
case TYPE_PAIR(IS_DOUBLE, IS_DOUBLE)://同上
Z_DVAL_P(result) = Z_DVAL_P(op1) - Z_DVAL_P(op2);
ZVAL_LONG(result, ZEND_NORMALIZE_BOOL(Z_DVAL_P(result)));
return SUCCESS;
case TYPE_PAIR(IS_ARRAY, IS_ARRAY)://数组比较，todo
zend_compare_arrays(result, op1, op2 TSRMLS_CC);
return SUCCESS;
case TYPE_PAIR(IS_NULL, IS_NULL)://null
ZVAL_LONG(result, 0);
return SUCCESS;
case TYPE_PAIR(IS_NULL, IS_BOOL)://null bool
ZVAL_LONG(result, Z_LVAL_P(op2) ? -1 : 0);
return SUCCESS;
case TYPE_PAIR(IS_BOOL, IS_NULL)://同上
ZVAL_LONG(result, Z_LVAL_P(op1) ? 1 : 0);
return SUCCESS;
case TYPE_PAIR(IS_BOOL, IS_BOOL)://bool，相减
ZVAL_LONG(result, ZEND_NORMALIZE_BOOL(Z_LVAL_P(op1) - Z_LVAL_P(op2)));
return SUCCESS;
case TYPE_PAIR(IS_STRING, IS_STRING)://两个字符串 todo
zendi_smart_strcmp(result, op1, op2);
return SUCCESS;
case TYPE_PAIR(IS_NULL, IS_STRING)://字符串 null
ZVAL_LONG(result, zend_binary_strcmp("", 0, Z_STRVAL_P(op2), Z_STRLEN_P(op2)));
return SUCCESS;
case TYPE_PAIR(IS_STRING, IS_NULL)://同上
ZVAL_LONG(result, zend_binary_strcmp(Z_STRVAL_P(op1), Z_STRLEN_P(op1), "", 0));
return SUCCESS;
case TYPE_PAIR(IS_OBJECT, IS_NULL)://object null，
ZVAL_LONG(result, 1);
return SUCCESS;
case TYPE_PAIR(IS_NULL, IS_OBJECT)://同上
ZVAL_LONG(result, -1);
return SUCCESS;
case TYPE_PAIR(IS_OBJECT, IS_OBJECT)://object todo
/* If both are objects sharing the same comparision handler then use is */
if (Z_OBJ_HANDLER_P(op1,compare_objects) == Z_OBJ_HANDLER_P(op2,compare_objects)) {
if (Z_OBJ_HANDLE_P(op1) == Z_OBJ_HANDLE_P(op2)) {
/* object handles are identical, apprently this is the same object */
ZVAL_LONG(result, 0);
return SUCCESS;
}
ZVAL_LONG(result, Z_OBJ_HT_P(op1)->compare_objects(op1, op2 TSRMLS_CC));
return SUCCESS;
}
/* break missing intentionally */
default:
if (Z_TYPE_P(op1) == IS_OBJECT) {
if (Z_OBJ_HT_P(op1)->get) {
op_free = Z_OBJ_HT_P(op1)->get(op1 TSRMLS_CC);
ret = compare_function(result, op_free, op2 TSRMLS_CC);
zend_free_obj_get_result(op_free TSRMLS_CC);
return ret;
} else if (Z_TYPE_P(op2) != IS_OBJECT && Z_OBJ_HT_P(op1)->cast_object) {
ALLOC_INIT_ZVAL(op_free);
if (Z_OBJ_HT_P(op1)->cast_object(op1, op_free, Z_TYPE_P(op2) TSRMLS_CC) == FAILURE) {
ZVAL_LONG(result, 1);
zend_free_obj_get_result(op_free TSRMLS_CC);
return SUCCESS;
}
ret = compare_function(result, op_free, op2 TSRMLS_CC);
zend_free_obj_get_result(op_free TSRMLS_CC);
return ret;
}
}
if (Z_TYPE_P(op2) == IS_OBJECT) {
if (Z_OBJ_HT_P(op2)->get) {
op_free = Z_OBJ_HT_P(op2)->get(op2 TSRMLS_CC);
ret = compare_function(result, op1, op_free TSRMLS_CC);
zend_free_obj_get_result(op_free TSRMLS_CC);
return ret;
} else if (Z_TYPE_P(op1) != IS_OBJECT && Z_OBJ_HT_P(op2)->cast_object) {
ALLOC_INIT_ZVAL(op_free);
if (Z_OBJ_HT_P(op2)->cast_object(op2, op_free, Z_TYPE_P(op1) TSRMLS_CC) == FAILURE) {
ZVAL_LONG(result, -1);
zend_free_obj_get_result(op_free TSRMLS_CC);
return SUCCESS;
}
ret = compare_function(result, op1, op_free TSRMLS_CC);
zend_free_obj_get_result(op_free TSRMLS_CC);
return ret;
} else if (Z_TYPE_P(op1) == IS_OBJECT) {
ZVAL_LONG(result, 1);
return SUCCESS;
}
}
if (!converted) {
if (Z_TYPE_P(op1) == IS_NULL) {
zendi_convert_to_boolean(op2, op2_copy, result);
ZVAL_LONG(result, Z_LVAL_P(op2) ? -1 : 0);
return SUCCESS;
} else if (Z_TYPE_P(op2) == IS_NULL) {
zendi_convert_to_boolean(op1, op1_copy, result);
ZVAL_LONG(result, Z_LVAL_P(op1) ? 1 : 0);
return SUCCESS;
} else if (Z_TYPE_P(op1) == IS_BOOL) {
zendi_convert_to_boolean(op2, op2_copy, result);
ZVAL_LONG(result, ZEND_NORMALIZE_BOOL(Z_LVAL_P(op1) - Z_LVAL_P(op2)));
return SUCCESS;
} else if (Z_TYPE_P(op2) == IS_BOOL) {
zendi_convert_to_boolean(op1, op1_copy, result);
ZVAL_LONG(result, ZEND_NORMALIZE_BOOL(Z_LVAL_P(op1) - Z_LVAL_P(op2)));
return SUCCESS;
} else {
zendi_convert_scalar_to_number(op1, op1_copy, result);
zendi_convert_scalar_to_number(op2, op2_copy, result);
converted = 1;
}
} else if (Z_TYPE_P(op1)==IS_ARRAY) {
ZVAL_LONG(result, 1);
return SUCCESS;
} else if (Z_TYPE_P(op2)==IS_ARRAY) {
ZVAL_LONG(result, -1);
return SUCCESS;
} else if (Z_TYPE_P(op1)==IS_OBJECT) {
ZVAL_LONG(result, 1);
return SUCCESS;
} else if (Z_TYPE_P(op2)==IS_OBJECT) {
ZVAL_LONG(result, -1);
return SUCCESS;
} else {
ZVAL_LONG(result, 0);
return FAILURE;
}
}
