text: /*
     +----------------------------------------------------------------------+
     | Zend Engine, e-SSA based Type & Range Inference                      |
     +----------------------------------------------------------------------+
     | Copyright (c) The PHP Group                                          |
     +----------------------------------------------------------------------+
     | This source file is subject to version 3.01 of the PHP license,      |
     | that is bundled with this package in the file LICENSE, and is        |
     | available through the world-wide-web at the following url:           |
     | http://www.php.net/license/3_01.txt                                  |
     | If you did not receive a copy of the PHP license and are unable to   |
     | obtain it through the world-wide-web, please send a note to          |
     | license@php.net so we can mail you a copy immediately.               |
     +----------------------------------------------------------------------+
     | Authors: Dmitry Stogov <dmitry@php.net>                              |
     +----------------------------------------------------------------------+
  */
  
  #ifndef ZEND_INFERENCE_H
  #define ZEND_INFERENCE_H
  
  #include "zend_optimizer.h"
  #include "zend_ssa.h"
  #include "zend_bitset.h"
  
  /* Bitmask for type inference (zend_ssa_var_info.type) */
  #include "zend_type_info.h"
  
  #define MAY_BE_PACKED_GUARD         (1<<27) /* needs packed array guard */
  #define MAY_BE_CLASS_GUARD          (1<<27) /* needs class guard */
  #define MAY_BE_GUARD                (1<<28) /* needs type guard */
  //#define MAY_BE_IN_REG               (1<<29) /* deprecated and not used */
  
  //TODO: remome MAY_BE_RC1, MAY_BE_RCN???
  #define MAY_BE_RC1                  (1<<30) /* may be non-reference with refcount == 1 */
  #define MAY_BE_RCN                  (1u<<31) /* may be non-reference with refcount > 1  */
  
  #define MAY_HAVE_DTOR \
  	(MAY_BE_OBJECT|MAY_BE_RESOURCE \
  	|MAY_BE_ARRAY_OF_ARRAY|MAY_BE_ARRAY_OF_OBJECT|MAY_BE_ARRAY_OF_RESOURCE)
  
  #define DEFINE_SSA_OP_HAS_RANGE(opN) \
  	static zend_always_inline bool _ssa_##opN##_has_range(const zend_op_array *op_array, const zend_ssa *ssa, const zend_op *opline, const zend_ssa_op *ssa_op) \
  	{ \
  		if (opline->opN##_type == IS_CONST) { \
  			zval *zv = CRT_CONSTANT(opline->opN); \
  			return (Z_TYPE_P(zv) == IS_LONG || Z_TYPE_P(zv) == IS_TRUE || Z_TYPE_P(zv) == IS_FALSE || Z_TYPE_P(zv) == IS_NULL); \
  		} else { \
  			return (opline->opN##_type != IS_UNUSED && \
  		        ssa->var_info && \
  		        ssa_op->opN##_use >= 0 && \
  			    ssa->var_info[ssa_op->opN##_use].has_range); \
  		} \
  		return 0; \
  	} \
  
  #define DEFINE_SSA_OP_MIN_RANGE(opN) \
  	static zend_always_inline zend_long _ssa_##opN##_min_range(const zend_op_array *op_array, const zend_ssa *ssa, const zend_op *opline, const zend_ssa_op *ssa_op) \
  	{ \
  		if (opline->opN##_type == IS_CONST) { \
  			zval *zv = CRT_CONSTANT(opline->opN); \
  			if (Z_TYPE_P(zv) == IS_LONG) { \
  				return Z_LVAL_P(zv); \
  			} else if (Z_TYPE_P(zv) == IS_TRUE) { \
  				return 1; \
  			} else if (Z_TYPE_P(zv) == IS_FALSE) { \
  				return 0; \
  			} else if (Z_TYPE_P(zv) == IS_NULL) { \
  				return 0; \
  			} \
  		} else if (opline->opN##_type != IS_UNUSED && \
  		    ssa->var_info && \
  		    ssa_op->opN##_use >= 0 && \
  		    ssa->var_info[ssa_op->opN##_use].has_range) { \
  			return ssa->var_info[ssa_op->opN##_use].range.min; \
  		} \
  		return ZEND_LONG_MIN; \
  	} \
  
  #define DEFINE_SSA_OP_MAX_RANGE(opN) \
  	static zend_always_inline zend_long _ssa_##opN##_max_range(const zend_op_array *op_array, const zend_ssa *ssa, const zend_op *opline, const zend_ssa_op *ssa_op) \
  	{ \
  		if (opline->opN##_type == IS_CONST) { \
  			zval *zv = CRT_CONSTANT(opline->opN); \
  			if (Z_TYPE_P(zv) == IS_LONG) { \
  				return Z_LVAL_P(zv); \
  			} else if (Z_TYPE_P(zv) == IS_TRUE) { \
  				return 1; \
  			} else if (Z_TYPE_P(zv) == IS_FALSE) { \
  				return 0; \
  			} else if (Z_TYPE_P(zv) == IS_NULL) { \
  				return 0; \
  			} \
  		} else if (opline->opN##_type != IS_UNUSED && \
  		    ssa->var_info && \
  		    ssa_op->opN##_use >= 0 && \
  		    ssa->var_info[ssa_op->opN##_use].has_range) { \
  			return ssa->var_info[ssa_op->opN##_use].range.max; \
  		} \
  		return ZEND_LONG_MAX; \
  	} \
  
  #define DEFINE_SSA_OP_RANGE_UNDERFLOW(opN) \
  	static zend_always_inline char _ssa_##opN##_range_underflow(const zend_op_array *op_array, const zend_ssa *ssa, const zend_op *opline, const zend_ssa_op *ssa_op) \
  	{ \
  		if (opline->opN##_type == IS_CONST) { \
  			zval *zv = CRT_CONSTANT(opline->opN); \
  			if (Z_TYPE_P(zv) == IS_LONG || Z_TYPE_P(zv) == IS_TRUE || Z_TYPE_P(zv) == IS_FALSE || Z_TYPE_P(zv) == IS_NULL) { \
  				return 0; \
  			} \
  		} else if (opline->opN##_type != IS_UNUSED && \
  		    ssa->var_info && \
  		    ssa_op->opN##_use >= 0 && \
  		    ssa->var_info[ssa_op->opN##_use].has_range) { \
  			return ssa->var_info[ssa_op->opN##_use].range.underflow; \
  		} \
  		return 1; \
  	} \
  
  #define DEFINE_SSA_OP_RANGE_OVERFLOW(opN) \
  	static zend_always_inline char _ssa_##opN##_range_overflow(const zend_op_array *op_array, const zend_ssa *ssa, const zend_op *opline, const zend_ssa_op *ssa_op) \
  	{ \
  		if (opline->opN##_type == IS_CONST) { \
  			zval *zv = CRT_CONSTANT(opline->opN); \
  			if (Z_TYPE_P(zv) == IS_LONG || Z_TYPE_P(zv) == IS_TRUE || Z_TYPE_P(zv) == IS_FALSE || Z_TYPE_P(zv) == IS_NULL) { \
  				return 0; \
  			} \
  		} else if (opline->opN##_type != IS_UNUSED && \
  		    ssa->var_info && \
  		    ssa_op->opN##_use >= 0 && \
  		    ssa->var_info[ssa_op->opN##_use].has_range) { \
  			return ssa->var_info[ssa_op->opN##_use].range.overflow; \
  		} \
  		return 1; \
  	} \
  
  DEFINE_SSA_OP_HAS_RANGE(op1)
  DEFINE_SSA_OP_MIN_RANGE(op1)
  DEFINE_SSA_OP_MAX_RANGE(op1)
  DEFINE_SSA_OP_RANGE_UNDERFLOW(op1)
  DEFINE_SSA_OP_RANGE_OVERFLOW(op1)
  DEFINE_SSA_OP_HAS_RANGE(op2)
  DEFINE_SSA_OP_MIN_RANGE(op2)
  DEFINE_SSA_OP_MAX_RANGE(op2)
  DEFINE_SSA_OP_RANGE_UNDERFLOW(op2)
  DEFINE_SSA_OP_RANGE_OVERFLOW(op2)
  
  #define OP1_HAS_RANGE()       (_ssa_op1_has_range (op_array, ssa, opline, ssa_op))
  #define OP1_MIN_RANGE()       (_ssa_op1_min_range (op_array, ssa, opline, ssa_op))
  #define OP1_MAX_RANGE()       (_ssa_op1_max_range (op_array, ssa, opline, ssa_op))
  #define OP1_RANGE_UNDERFLOW() (_ssa_op1_range_underflow (op_array, ssa, opline, ssa_op))
  #define OP1_RANGE_OVERFLOW()  (_ssa_op1_range_overflow (op_array, ssa, opline, ssa_op))
  #define OP2_HAS_RANGE()       (_ssa_op2_has_range (op_array, ssa, opline, ssa_op))
  #define OP2_MIN_RANGE()       (_ssa_op2_min_range (op_array, ssa, opline, ssa_op))
  #define OP2_MAX_RANGE()       (_ssa_op2_max_range (op_array, ssa, opline, ssa_op))
  #define OP2_RANGE_UNDERFLOW() (_ssa_op2_range_underflow (op_array, ssa, opline, ssa_op))
  #define OP2_RANGE_OVERFLOW()  (_ssa_op2_range_overflow (op_array, ssa, opline, ssa_op))
  
  static zend_always_inline uint32_t _const_op_type(const zval *zv) {
  	if (Z_TYPE_P(zv) == IS_CONSTANT_AST) {
  		return MAY_BE_RC1 | MAY_BE_RCN | MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY;
  	} else if (Z_TYPE_P(zv) == IS_ARRAY) {
  		HashTable *ht = Z_ARRVAL_P(zv);
  		uint32_t tmp = MAY_BE_ARRAY;
  		zend_string *str;
  		zval *val;
  
  		if (Z_REFCOUNTED_P(zv)) {
  			tmp |= MAY_BE_RC1 | MAY_BE_RCN;
  		} else {
  			tmp |= MAY_BE_RCN;
  		}
  
  		ZEND_HASH_FOREACH_STR_KEY_VAL(ht, str, val) {
  			if (str) {
  				tmp |= MAY_BE_ARRAY_KEY_STRING;
  			} else {
  				tmp |= MAY_BE_ARRAY_KEY_LONG;
  			}
  			tmp |= 1 << (Z_TYPE_P(val) + MAY_BE_ARRAY_SHIFT);
  		} ZEND_HASH_FOREACH_END();
  		if (HT_IS_PACKED(ht)) {
  			tmp &= ~MAY_BE_ARRAY_HASH;
  		}
  		return tmp;
  	} else {
  		uint32_t tmp = (1 << Z_TYPE_P(zv));
  
  		if (Z_REFCOUNTED_P(zv)) {
  			tmp |= MAY_BE_RC1 | MAY_BE_RCN;
  		} else if (Z_TYPE_P(zv) == IS_STRING) {
  			tmp |= MAY_BE_RCN;
  		}
  		return tmp;
  	}
  }
  
  static zend_always_inline uint32_t get_ssa_var_info(const zend_ssa *ssa, int ssa_var_num)
  {
  	if (ssa->var_info && ssa_var_num >= 0) {
  		return ssa->var_info[ssa_var_num].type;
  	} else {
  		return MAY_BE_UNDEF | MAY_BE_RC1 | MAY_BE_RCN | MAY_BE_REF | MAY_BE_INDIRECT | MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
  	}
  }
  
  #define DEFINE_SSA_OP_INFO(opN) \
  	static zend_always_inline uint32_t _ssa_##opN##_info(const zend_op_array *op_array, const zend_ssa *ssa, const zend_op *opline, const zend_ssa_op *ssa_op) \
  	{																		\
  		if (opline->opN##_type == IS_CONST) {							\
  			return _const_op_type(CRT_CONSTANT(opline->opN)); \
  		} else { \
  			return get_ssa_var_info(ssa, ssa->var_info ? ssa_op->opN##_use : -1); \
  		} \
  	} \
  
  #define DEFINE_SSA_OP_DEF_INFO(opN) \
  	static zend_always_inline uint32_t _ssa_##opN##_def_info(const zend_op_array *op_array, const zend_ssa *ssa, const zend_op *opline, const zend_ssa_op *ssa_op) \
  	{ \
  		return get_ssa_var_info(ssa, ssa->var_info ? ssa_op->opN##_def : -1); \
  	} \
  
  
  DEFINE_SSA_OP_INFO(op1)
  DEFINE_SSA_OP_INFO(op2)
  DEFINE_SSA_OP_INFO(result)
  DEFINE_SSA_OP_DEF_INFO(op1)
  DEFINE_SSA_OP_DEF_INFO(op2)
  DEFINE_SSA_OP_DEF_INFO(result)
  
  #define OP1_INFO()           (_ssa_op1_info(op_array, ssa, opline, ssa_op))
  #define OP2_INFO()           (_ssa_op2_info(op_array, ssa, opline, ssa_op))
  #define OP1_DATA_INFO()      (_ssa_op1_info(op_array, ssa, (opline+1), (ssa_op+1)))
  #define OP2_DATA_INFO()      (_ssa_op2_info(op_array, ssa, (opline+1), (ssa_op+1)))
  #define RES_USE_INFO()       (_ssa_result_info(op_array, ssa, opline, ssa_op))
  #define OP1_DEF_INFO()       (_ssa_op1_def_info(op_array, ssa, opline, ssa_op))
  #define OP2_DEF_INFO()       (_ssa_op2_def_info(op_array, ssa, opline, ssa_op))
  #define OP1_DATA_DEF_INFO()  (_ssa_op1_def_info(op_array, ssa, (opline+1), (ssa_op+1)))
  #define OP2_DATA_DEF_INFO()  (_ssa_op2_def_info(op_array, ssa, (opline+1), (ssa_op+1)))
  #define RES_INFO()           (_ssa_result_def_info(op_array, ssa, opline, ssa_op))
  
  static zend_always_inline bool zend_add_will_overflow(zend_long a, zend_long b) {
  	return (b > 0 && a > ZEND_LONG_MAX - b)
  		|| (b < 0 && a < ZEND_LONG_MIN - b);
  }
  static zend_always_inline bool zend_sub_will_overflow(zend_long a, zend_long b) {
  	return (b > 0 && a < ZEND_LONG_MIN + b)
  		|| (b < 0 && a > ZEND_LONG_MAX + b);
  }
  
  BEGIN_EXTERN_C()
  
  ZEND_API int zend_ssa_find_false_dependencies(const zend_op_array *op_array, zend_ssa *ssa);
  ZEND_API int zend_ssa_find_sccs(const zend_op_array *op_array, zend_ssa *ssa);
  ZEND_API int zend_ssa_inference(zend_arena **raena, const zend_op_array *op_array, const zend_script *script, zend_ssa *ssa, zend_long optimization_level);
  
  ZEND_API uint32_t zend_array_element_type(uint32_t t1, zend_uchar op_type, int write, int insert);
  
  int  zend_inference_calc_range(const zend_op_array *op_array, zend_ssa *ssa, int var, int widening, int narrowing, zend_ssa_range *tmp);
  ZEND_API int zend_inference_propagate_range(const zend_op_array *op_array, zend_ssa *ssa, zend_op *opline, zend_ssa_op* ssa_op, int var, zend_ssa_range *tmp);
  void zend_inference_init_range(const zend_op_array *op_array, zend_ssa *ssa, int var, bool underflow, zend_long min, zend_long max, bool overflow);
  int  zend_inference_narrowing_meet(zend_ssa_var_info *var_info, zend_ssa_range *r);
  int  zend_inference_widening_meet(zend_ssa_var_info *var_info, zend_ssa_range *r);
  void zend_inference_check_recursive_dependencies(zend_op_array *op_array);
  
  int  zend_infer_types_ex(const zend_op_array *op_array, const zend_script *script, zend_ssa *ssa, zend_bitset worklist, zend_long optimization_level);
  
  ZEND_API uint32_t zend_fetch_arg_info_type(
  	const zend_script *script, zend_arg_info *arg_info, zend_class_entry **pce);
  ZEND_API void zend_init_func_return_info(
  	const zend_op_array *op_array, const zend_script *script, zend_ssa_var_info *ret);
  uint32_t zend_get_return_info_from_signature_only(
  		const zend_function *func, const zend_script *script,
  		zend_class_entry **ce, bool *ce_is_instanceof);
  void zend_func_return_info(const zend_op_array   *op_array,
                             const zend_script     *script,
                             int                    recursive,
                             int                    widening,
                             zend_ssa_var_info     *ret);
  
  ZEND_API int zend_may_throw_ex(const zend_op *opline, const zend_ssa_op *ssa_op, const zend_op_array *op_array, zend_ssa *ssa, uint32_t t1, uint32_t t2);
  ZEND_API int zend_may_throw(const zend_op *opline, const zend_ssa_op *ssa_op, const zend_op_array *op_array, zend_ssa *ssa);
  
  ZEND_API int zend_update_type_info(
  	const zend_op_array *op_array, zend_ssa *ssa, const zend_script *script,
  	zend_op *opline, zend_ssa_op *ssa_op, const zend_op **ssa_opcodes,
  	zend_long optimization_level);
  
  END_EXTERN_C()
  
  #endif /* ZEND_INFERENCE_H */
  