PHP7 の zval についての深い理解

struct _zval_struct { union { long lval; double dval; struct { char *val; int len;        } str;        HashTable *ht;        zend_object_value obj;        zend_ast *ast;    } value;    zend_uint refcount__gc;    zend_uchar type;    zend_uchar is_ref__gc;};

/* The following macroses override macroses from zend_alloc.h */ #undef ALLOC_ZVAL#define ALLOC_ZVAL(z)                                   \ do {                                                \        (z) = (zval*)emalloc(sizeof(zval_gc_info));     \ GC_ZVAL_INIT(z);                                \    } while (0)

typedef struct _zval_gc_info {    zval z; union {        gc_root_buffer       *buffered; struct _zval_gc_info *next;    } u;} zval_gc_info;

Z_STRVAL_PP(ppzval) = erealloc(Z_STRVAL_PP(ppzval), Z_STRLEN_PP(ppzval) + 1 + PHP_TAINT_MAGIC_LENGTH); PHP_TAINT_MARK(*ppzval, PHP_TAINT_MAGIC_POSSIBLE);

typedef struct _zend_object_store_bucket {    zend_bool destructor_called;    zend_bool valid; union _store_bucket { struct _store_object { void *object; zend_objects_store_dtor_t dtor; zend_objects_free_object_storage_t free_storage; zend_objects_store_clone_t clone; const zend_object_handlers *handlers;            zend_uint refcount;            gc_root_buffer *buffered;        } obj; struct { int next;        } free_list;    } bucket;} zend_object_store_bucket;

<?php   function dummy($array) {}   $array = range(1, 100000);   $b = &$array;   dummy($b); ?>

<?php $array = range(1, 100000);  function dummy($array) {}  $i = 0; $start = microtime(true); while($i++ < 100) {  dummy($array); }  printf("Used %sS\n", microtime(true) - $start);  $b = &$array; //注意这里, 假设我不小心把这个Array引用给了一个变量 $i = 0; $start = microtime(true); while($i++ < 100) {  dummy($array); } printf("Used %sS\n", microtime(true) - $start); ?>

$ php-5.6/sapi/cli/php /tmp/1.phpUsed 0.00045204162597656SUsed 4.2051479816437S

PHP_FUNCTION(pathinfo){..... MAKE_STD_ZVAL(tmp); array_init(tmp);.... if (opt == PHP_PATHINFO_ALL) { RETURN_ZVAL(tmp, 0, 1);    } else {.....}

struct _zval_struct { union {        zend_long         lval; /* long value */ double dval; /* double value */ zend_refcounted  *counted;        zend_string      *str;        zend_array       *arr;        zend_object      *obj;        zend_resource    *res;        zend_reference   *ref;        zend_ast_ref     *ast;        zval             *zv; void *ptr;        zend_class_entry *ce;        zend_function    *func; struct { uint32_t w1; uint32_t w2;        } ww;    } value; union { struct { ZEND_ENDIAN_LOHI_4(                zend_uchar    type, /* active type */ zend_uchar    type_flags,                zend_uchar    const_flags,                zend_uchar    reserved) /* call info for EX(This) */ } v; uint32_t type_info;    } u1; union { uint32_t var_flags; uint32_t next; /* hash collision chain */ uint32_t cache_slot; /* literal cache slot */ uint32_t lineno; /* line number (for ast nodes) */ uint32_t num_args; /* arguments number for EX(This) */ uint32_t fe_pos; /* foreach position */ uint32_t fe_iter_idx; /* foreach iterator index */ } u2;};

/* regular data types */ #define IS_UNDEF 0 #define IS_NULL 1 #define IS_FALSE 2 #define IS_TRUE 3 #define IS_LONG 4 #define IS_DOUBLE 5 #define IS_STRING 6 #define IS_ARRAY 7 #define IS_OBJECT 8 #define IS_RESOURCE 9 #define IS_REFERENCE 10 /* constant expressions */ #define IS_CONSTANT 11 #define IS_CONSTANT_AST 12 /* fake types */ #define _IS_BOOL 13 #define IS_CALLABLE 14 /* internal types */ #define IS_INDIRECT 15 #define IS_PTR 17

IS_LONGIS_DOUBLE

IS_NULLIS_FALSEIS_TRUE

struct _zend_array {    zend_refcounted_h gc; union { struct { ZEND_ENDIAN_LOHI_4(                zend_uchar    flags,                zend_uchar    nApplyCount,                zend_uchar    nIteratorsCount,                zend_uchar    reserve)        } v; uint32_t flags;    } u; uint32_t nTableMask;    Bucket           *arData; uint32_t nNumUsed; uint32_t nNumOfElements; uint32_t nTableSize; uint32_t nInternalPointer;    zend_long         nNextFreeElement; dtor_func_t pDestructor;};

typedef struct _zend_refcounted_h { uint32_t refcount; /* reference counter 32-bit */ union { struct { ZEND_ENDIAN_LOHI_3(                zend_uchar    type,                zend_uchar    flags, /* used for strings & objects */ uint16_t gc_info) /* keeps GC root number (or 0) and color */ } v; uint32_t type_info;    } u;} zend_refcounted_h;

arr1.u.flags = arr2.u.flags;

arr1.u.v.flags              = arr2.u.v.flags;arr1.u.v.nApplyCount        = arr2.u.v.nApplyCount;arr1.u.v.nIteratorsCount    = arr2.u.v.nIteratorsCount;arr1.u.v.reserve            = arr2.u.v.reserve;