/src/php-src/Zend/Optimizer/zend_dfg.c

Source
/*
   +----------------------------------------------------------------------+
   | Zend Engine, DFG - Data Flow Graph                                   |
   +----------------------------------------------------------------------+
   | 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:           |
   | https://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>                              |
   +----------------------------------------------------------------------+
*/

#include "zend_compile.h"
#include "zend_dfg.h"

static zend_always_inline void zend_dfg_add_use_def_op_impl(const zend_op_array *op_array, const zend_op *opline, uint32_t build_flags, zend_bitset use, zend_bitset def) /* {{{ */
{
  uint32_t var_num;
  const zend_op *next;

  if (opline->op1_type & (IS_CV|IS_VAR|IS_TMP_VAR)) {
    var_num = EX_VAR_TO_NUM(opline->op1.var);
    if (!zend_bitset_in(def, var_num)) {
      zend_bitset_incl(use, var_num);
    }
  }
  if (((opline->op2_type & (IS_VAR|IS_TMP_VAR)) != 0
    && opline->opcode != ZEND_FE_FETCH_R
    && opline->opcode != ZEND_FE_FETCH_RW)
   || (opline->op2_type == IS_CV)) {
    var_num = EX_VAR_TO_NUM(opline->op2.var);
    if (!zend_bitset_in(def, var_num)) {
      zend_bitset_incl(use, var_num);
    }
  }
  if ((build_flags & ZEND_SSA_USE_CV_RESULTS)
   && opline->result_type == IS_CV
   && opline->opcode != ZEND_RECV) {
    var_num = EX_VAR_TO_NUM(opline->result.var);
    if (!zend_bitset_in(def, var_num)) {
      zend_bitset_incl(use, var_num);
    }
  }

  switch (opline->opcode) {
    case ZEND_ASSIGN:
      if ((build_flags & ZEND_SSA_RC_INFERENCE) && opline->op2_type == IS_CV) {
        zend_bitset_incl(def, EX_VAR_TO_NUM(opline->op2.var));
      }
      if (opline->op1_type == IS_CV) {
add_op1_def:
        zend_bitset_incl(def, EX_VAR_TO_NUM(opline->op1.var));
      }
      break;
    case ZEND_ASSIGN_REF:
      if (opline->op2_type == IS_CV) {
        zend_bitset_incl(def, EX_VAR_TO_NUM(opline->op2.var));
      }
      if (opline->op1_type == IS_CV) {
        goto add_op1_def;
      }
      break;
    case ZEND_ASSIGN_DIM:
    case ZEND_ASSIGN_OBJ:
      next = opline + 1;
      if (next->op1_type & (IS_CV|IS_VAR|IS_TMP_VAR)) {
        var_num = EX_VAR_TO_NUM(next->op1.var);
        if (!zend_bitset_in(def, var_num)) {
          zend_bitset_incl(use, var_num);
        }
        if (build_flags & ZEND_SSA_RC_INFERENCE && next->op1_type == IS_CV) {
          zend_bitset_incl(def, var_num);
        }
      }
      if (opline->op1_type == IS_CV) {
        goto add_op1_def;
      }
      break;
    case ZEND_ASSIGN_OBJ_REF:
      next = opline + 1;
      if (next->op1_type & (IS_CV|IS_VAR|IS_TMP_VAR)) {
        var_num = EX_VAR_TO_NUM(next->op1.var);
        if (!zend_bitset_in(def, var_num)) {
          zend_bitset_incl(use, var_num);
        }
        if (next->op1_type == IS_CV) {
          zend_bitset_incl(def, var_num);
        }
      }
      if (opline->op1_type == IS_CV) {
        goto add_op1_def;
      }
      break;
    case ZEND_ASSIGN_STATIC_PROP:
      next = opline + 1;
      if (next->op1_type & (IS_CV|IS_VAR|IS_TMP_VAR)) {
        var_num = EX_VAR_TO_NUM(next->op1.var);
        if (!zend_bitset_in(def, var_num)) {
          zend_bitset_incl(use, var_num);
        }
        if ((build_flags & ZEND_SSA_RC_INFERENCE) && next->op1_type == IS_CV) {
          zend_bitset_incl(def, var_num);
        }
      }
      break;
    case ZEND_ASSIGN_STATIC_PROP_REF:
      next = opline + 1;
      if (next->op1_type & (IS_CV|IS_VAR|IS_TMP_VAR)) {
        var_num = EX_VAR_TO_NUM(next->op1.var);
        if (!zend_bitset_in(def, var_num)) {
          zend_bitset_incl(use, var_num);
        }
        if (next->op1_type == IS_CV) {
          zend_bitset_incl(def, var_num);
        }
      }
      break;
    case ZEND_ASSIGN_STATIC_PROP_OP:
    case ZEND_FRAMELESS_ICALL_3:
      next = opline + 1;
      if (next->op1_type & (IS_CV|IS_VAR|IS_TMP_VAR)) {
        var_num = EX_VAR_TO_NUM(next->op1.var);
        if (!zend_bitset_in(def, var_num)) {
          zend_bitset_incl(use, var_num);
        }
      }
      break;
    case ZEND_ASSIGN_DIM_OP:
    case ZEND_ASSIGN_OBJ_OP:
      next = opline + 1;
      if (next->op1_type & (IS_CV|IS_VAR|IS_TMP_VAR)) {
        var_num = EX_VAR_TO_NUM(next->op1.var);
        if (!zend_bitset_in(def, var_num)) {
          zend_bitset_incl(use, var_num);
        }
      }
      if (opline->op1_type == IS_CV) {
        goto add_op1_def;
      }
      break;
    case ZEND_ASSIGN_OP:
    case ZEND_PRE_INC:
    case ZEND_PRE_DEC:
    case ZEND_POST_INC:
    case ZEND_POST_DEC:
    case ZEND_BIND_GLOBAL:
    case ZEND_BIND_STATIC:
    case ZEND_BIND_INIT_STATIC_OR_JMP:
    case ZEND_SEND_VAR_NO_REF:
    case ZEND_SEND_VAR_NO_REF_EX:
    case ZEND_SEND_VAR_EX:
    case ZEND_SEND_FUNC_ARG:
    case ZEND_SEND_REF:
    case ZEND_SEND_UNPACK:
    case ZEND_FE_RESET_RW:
    case ZEND_MAKE_REF:
    case ZEND_PRE_INC_OBJ:
    case ZEND_PRE_DEC_OBJ:
    case ZEND_POST_INC_OBJ:
    case ZEND_POST_DEC_OBJ:
    case ZEND_UNSET_DIM:
    case ZEND_UNSET_OBJ:
    case ZEND_FETCH_DIM_W:
    case ZEND_FETCH_DIM_RW:
    case ZEND_FETCH_DIM_FUNC_ARG:
    case ZEND_FETCH_DIM_UNSET:
    case ZEND_FETCH_LIST_W:
      if (opline->op1_type == IS_CV) {
        goto add_op1_def;
      }
      break;
    case ZEND_SEND_VAR:
    case ZEND_CAST:
    case ZEND_QM_ASSIGN:
    case ZEND_JMP_SET:
    case ZEND_COALESCE:
    case ZEND_FE_RESET_R:
      if ((build_flags & ZEND_SSA_RC_INFERENCE) && opline->op1_type == IS_CV) {
        goto add_op1_def;
      }
      break;
    case ZEND_ADD_ARRAY_UNPACK:
      var_num = EX_VAR_TO_NUM(opline->result.var);
      if (!zend_bitset_in(def, var_num)) {
        zend_bitset_incl(use, var_num);
      }
      break;
    case ZEND_ADD_ARRAY_ELEMENT:
      var_num = EX_VAR_TO_NUM(opline->result.var);
      if (!zend_bitset_in(def, var_num)) {
        zend_bitset_incl(use, var_num);
      }
      ZEND_FALLTHROUGH;
    case ZEND_INIT_ARRAY:
      if (((build_flags & ZEND_SSA_RC_INFERENCE)
            || (opline->extended_value & ZEND_ARRAY_ELEMENT_REF))
          && opline->op1_type == IS_CV) {
        goto add_op1_def;
      }
      break;
    case ZEND_YIELD:
      if (opline->op1_type == IS_CV
          && ((op_array->fn_flags & ZEND_ACC_RETURN_REFERENCE)
            || (build_flags & ZEND_SSA_RC_INFERENCE))) {
        goto add_op1_def;
      }
      break;
    case ZEND_UNSET_CV:
      goto add_op1_def;
    case ZEND_VERIFY_RETURN_TYPE:
      if (opline->op1_type & (IS_TMP_VAR|IS_VAR|IS_CV)) {
        goto add_op1_def;
      }
      break;
    case ZEND_FE_FETCH_R:
    case ZEND_FE_FETCH_RW:
#if 0
      /* This special case was handled above the switch */
      if (opline->op2_type != IS_CV) {
        op2_use = -1; /* not used */
      }
#endif
      zend_bitset_incl(def, EX_VAR_TO_NUM(opline->op2.var));
      break;
    case ZEND_BIND_LEXICAL:
      if ((opline->extended_value & ZEND_BIND_REF) || (build_flags & ZEND_SSA_RC_INFERENCE)) {
        zend_bitset_incl(def, EX_VAR_TO_NUM(opline->op2.var));
      }
      break;
    default:
      break;
  }

  if (opline->result_type & (IS_CV|IS_VAR|IS_TMP_VAR)) {
    zend_bitset_incl(def, EX_VAR_TO_NUM(opline->result.var));
  }
}
/* }}} */

ZEND_API void zend_dfg_add_use_def_op(const zend_op_array *op_array, const zend_op *opline, uint32_t build_flags, zend_bitset use, zend_bitset def) /* {{{ */
{
  zend_dfg_add_use_def_op_impl(op_array, opline, build_flags, use, def);
}
/* }}} */

void zend_build_dfg(const zend_op_array *op_array, const zend_cfg *cfg, const zend_dfg *dfg, uint32_t build_flags) /* {{{ */
{
  uint32_t set_size = dfg->size;
  zend_basic_block *blocks = cfg->blocks;
  int blocks_count = cfg->blocks_count;
  zend_bitset tmp, def, use, in, out;
  int k;
  int j;

  tmp = dfg->tmp;
  def = dfg->def;
  use = dfg->use;
  in  = dfg->in;
  out = dfg->out;

  /* Collect "def" and "use" sets */
  for (j = 0; j < blocks_count; j++) {
    const zend_op *opline, *end;
    zend_bitset b_use, b_def;

    if ((blocks[j].flags & ZEND_BB_REACHABLE) == 0) {
      continue;
    }

    opline = op_array->opcodes + blocks[j].start;
    end = opline + blocks[j].len;
    b_use = DFG_BITSET(use, set_size, j);
    b_def = DFG_BITSET(def, set_size, j);
    for (; opline < end; opline++) {
      if (opline->opcode != ZEND_OP_DATA) {
        zend_dfg_add_use_def_op_impl(op_array, opline, build_flags, b_use, b_def);
      }
    }
  }

  /* Calculate "in" and "out" sets */
  {
    uint32_t worklist_len = zend_bitset_len(blocks_count);
    zend_bitset worklist;
    ALLOCA_FLAG(use_heap);
    worklist = ZEND_BITSET_ALLOCA(worklist_len, use_heap);
    memset(worklist, 0, worklist_len * ZEND_BITSET_ELM_SIZE);
    for (j = 0; j < blocks_count; j++) {
      zend_bitset_incl(worklist, j);
    }
    while (!zend_bitset_empty(worklist, worklist_len)) {
      /* We use the last block on the worklist, because predecessors tend to be located
       * before the succeeding block, so this converges faster. */
      j = zend_bitset_last(worklist, worklist_len);
      zend_bitset_excl(worklist, j);

      if ((blocks[j].flags & ZEND_BB_REACHABLE) == 0) {
        continue;
      }
      if (blocks[j].successors_count != 0) {
        zend_bitset_copy(DFG_BITSET(out, set_size, j), DFG_BITSET(in, set_size, blocks[j].successors[0]), set_size);
        for (k = 1; k < blocks[j].successors_count; k++) {
          zend_bitset_union(DFG_BITSET(out, set_size, j), DFG_BITSET(in, set_size, blocks[j].successors[k]), set_size);
        }
      } else {
        zend_bitset_clear(DFG_BITSET(out, set_size, j), set_size);
      }
      zend_bitset_union_with_difference(tmp, DFG_BITSET(use, set_size, j), DFG_BITSET(out, set_size, j), DFG_BITSET(def, set_size, j), set_size);
      if (!zend_bitset_equal(DFG_BITSET(in, set_size, j), tmp, set_size)) {
        zend_bitset_copy(DFG_BITSET(in, set_size, j), tmp, set_size);

        /* Add predecessors of changed block to worklist */
        {
          const int *predecessors = &cfg->predecessors[blocks[j].predecessor_offset];
          for (k = 0; k < blocks[j].predecessors_count; k++) {
            zend_bitset_incl(worklist, predecessors[k]);
          }
        }
      }
    }

    free_alloca(worklist, use_heap);
  }
}
/* }}} */

Coverage Report

Created: 2025-12-14 06:05

Line	Count	Source
1		/*
2		+----------------------------------------------------------------------+
3		\| Zend Engine, DFG - Data Flow Graph \|
4		+----------------------------------------------------------------------+
5		\| Copyright (c) The PHP Group \|
6		+----------------------------------------------------------------------+
7		\| This source file is subject to version 3.01 of the PHP license, \|
8		\| that is bundled with this package in the file LICENSE, and is \|
9		\| available through the world-wide-web at the following url: \|
10		\| https://www.php.net/license/3_01.txt \|
11		\| If you did not receive a copy of the PHP license and are unable to \|
12		\| obtain it through the world-wide-web, please send a note to \|
13		\| license@php.net so we can mail you a copy immediately. \|
14		+----------------------------------------------------------------------+
15		\| Authors: Dmitry Stogov <dmitry@php.net> \|
16		+----------------------------------------------------------------------+
17		*/
18
19		#include "zend_compile.h"
20		#include "zend_dfg.h"
21
22		static zend_always_inline void zend_dfg_add_use_def_op_impl(const zend_op_array op_array, const zend_op opline, uint32_t build_flags, zend_bitset use, zend_bitset def) /* {{{ */
23	0	{
24	0	uint32_t var_num;
25	0	const zend_op *next;
26
27	0	if (opline->op1_type & (IS_CV\|IS_VAR\|IS_TMP_VAR)) {
28	0	var_num = EX_VAR_TO_NUM(opline->op1.var);
29	0	if (!zend_bitset_in(def, var_num)) {
30	0	zend_bitset_incl(use, var_num);
31	0	}
32	0	}
33	0	if (((opline->op2_type & (IS_VAR\|IS_TMP_VAR)) != 0
34	0	&& opline->opcode != ZEND_FE_FETCH_R
35	0	&& opline->opcode != ZEND_FE_FETCH_RW)
36	0	\|\| (opline->op2_type == IS_CV)) {
37	0	var_num = EX_VAR_TO_NUM(opline->op2.var);
38	0	if (!zend_bitset_in(def, var_num)) {
39	0	zend_bitset_incl(use, var_num);
40	0	}
41	0	}
42	0	if ((build_flags & ZEND_SSA_USE_CV_RESULTS)
43	0	&& opline->result_type == IS_CV
44	0	&& opline->opcode != ZEND_RECV) {
45	0	var_num = EX_VAR_TO_NUM(opline->result.var);
46	0	if (!zend_bitset_in(def, var_num)) {
47	0	zend_bitset_incl(use, var_num);
48	0	}
49	0	}
50
51	0	switch (opline->opcode) {
52	0	case ZEND_ASSIGN:
53	0	if ((build_flags & ZEND_SSA_RC_INFERENCE) && opline->op2_type == IS_CV) {
54	0	zend_bitset_incl(def, EX_VAR_TO_NUM(opline->op2.var));
55	0	}
56	0	if (opline->op1_type == IS_CV) {
57	0	add_op1_def:
58	0	zend_bitset_incl(def, EX_VAR_TO_NUM(opline->op1.var));
59	0	}
60	0	break;
61	0	case ZEND_ASSIGN_REF:
62	0	if (opline->op2_type == IS_CV) {
63	0	zend_bitset_incl(def, EX_VAR_TO_NUM(opline->op2.var));
64	0	}
65	0	if (opline->op1_type == IS_CV) {
66	0	goto add_op1_def;
67	0	}
68	0	break;
69	0	case ZEND_ASSIGN_DIM:
70	0	case ZEND_ASSIGN_OBJ:
71	0	next = opline + 1;
72	0	if (next->op1_type & (IS_CV\|IS_VAR\|IS_TMP_VAR)) {
73	0	var_num = EX_VAR_TO_NUM(next->op1.var);
74	0	if (!zend_bitset_in(def, var_num)) {
75	0	zend_bitset_incl(use, var_num);
76	0	}
77	0	if (build_flags & ZEND_SSA_RC_INFERENCE && next->op1_type == IS_CV) {
78	0	zend_bitset_incl(def, var_num);
79	0	}
80	0	}
81	0	if (opline->op1_type == IS_CV) {
82	0	goto add_op1_def;
83	0	}
84	0	break;
85	0	case ZEND_ASSIGN_OBJ_REF:
86	0	next = opline + 1;
87	0	if (next->op1_type & (IS_CV\|IS_VAR\|IS_TMP_VAR)) {
88	0	var_num = EX_VAR_TO_NUM(next->op1.var);
89	0	if (!zend_bitset_in(def, var_num)) {
90	0	zend_bitset_incl(use, var_num);
91	0	}
92	0	if (next->op1_type == IS_CV) {
93	0	zend_bitset_incl(def, var_num);
94	0	}
95	0	}
96	0	if (opline->op1_type == IS_CV) {
97	0	goto add_op1_def;
98	0	}
99	0	break;
100	0	case ZEND_ASSIGN_STATIC_PROP:
101	0	next = opline + 1;
102	0	if (next->op1_type & (IS_CV\|IS_VAR\|IS_TMP_VAR)) {
103	0	var_num = EX_VAR_TO_NUM(next->op1.var);
104	0	if (!zend_bitset_in(def, var_num)) {
105	0	zend_bitset_incl(use, var_num);
106	0	}
107	0	if ((build_flags & ZEND_SSA_RC_INFERENCE) && next->op1_type == IS_CV) {
108	0	zend_bitset_incl(def, var_num);
109	0	}
110	0	}
111	0	break;
112	0	case ZEND_ASSIGN_STATIC_PROP_REF:
113	0	next = opline + 1;
114	0	if (next->op1_type & (IS_CV\|IS_VAR\|IS_TMP_VAR)) {
115	0	var_num = EX_VAR_TO_NUM(next->op1.var);
116	0	if (!zend_bitset_in(def, var_num)) {
117	0	zend_bitset_incl(use, var_num);
118	0	}
119	0	if (next->op1_type == IS_CV) {
120	0	zend_bitset_incl(def, var_num);
121	0	}
122	0	}
123	0	break;
124	0	case ZEND_ASSIGN_STATIC_PROP_OP:
125	0	case ZEND_FRAMELESS_ICALL_3:
126	0	next = opline + 1;
127	0	if (next->op1_type & (IS_CV\|IS_VAR\|IS_TMP_VAR)) {
128	0	var_num = EX_VAR_TO_NUM(next->op1.var);
129	0	if (!zend_bitset_in(def, var_num)) {
130	0	zend_bitset_incl(use, var_num);
131	0	}
132	0	}
133	0	break;
134	0	case ZEND_ASSIGN_DIM_OP:
135	0	case ZEND_ASSIGN_OBJ_OP:
136	0	next = opline + 1;
137	0	if (next->op1_type & (IS_CV\|IS_VAR\|IS_TMP_VAR)) {
138	0	var_num = EX_VAR_TO_NUM(next->op1.var);
139	0	if (!zend_bitset_in(def, var_num)) {
140	0	zend_bitset_incl(use, var_num);
141	0	}
142	0	}
143	0	if (opline->op1_type == IS_CV) {
144	0	goto add_op1_def;
145	0	}
146	0	break;
147	0	case ZEND_ASSIGN_OP:
148	0	case ZEND_PRE_INC:
149	0	case ZEND_PRE_DEC:
150	0	case ZEND_POST_INC:
151	0	case ZEND_POST_DEC:
152	0	case ZEND_BIND_GLOBAL:
153	0	case ZEND_BIND_STATIC:
154	0	case ZEND_BIND_INIT_STATIC_OR_JMP:
155	0	case ZEND_SEND_VAR_NO_REF:
156	0	case ZEND_SEND_VAR_NO_REF_EX:
157	0	case ZEND_SEND_VAR_EX:
158	0	case ZEND_SEND_FUNC_ARG:
159	0	case ZEND_SEND_REF:
160	0	case ZEND_SEND_UNPACK:
161	0	case ZEND_FE_RESET_RW:
162	0	case ZEND_MAKE_REF:
163	0	case ZEND_PRE_INC_OBJ:
164	0	case ZEND_PRE_DEC_OBJ:
165	0	case ZEND_POST_INC_OBJ:
166	0	case ZEND_POST_DEC_OBJ:
167	0	case ZEND_UNSET_DIM:
168	0	case ZEND_UNSET_OBJ:
169	0	case ZEND_FETCH_DIM_W:
170	0	case ZEND_FETCH_DIM_RW:
171	0	case ZEND_FETCH_DIM_FUNC_ARG:
172	0	case ZEND_FETCH_DIM_UNSET:
173	0	case ZEND_FETCH_LIST_W:
174	0	if (opline->op1_type == IS_CV) {
175	0	goto add_op1_def;
176	0	}
177	0	break;
178	0	case ZEND_SEND_VAR:
179	0	case ZEND_CAST:
180	0	case ZEND_QM_ASSIGN:
181	0	case ZEND_JMP_SET:
182	0	case ZEND_COALESCE:
183	0	case ZEND_FE_RESET_R:
184	0	if ((build_flags & ZEND_SSA_RC_INFERENCE) && opline->op1_type == IS_CV) {
185	0	goto add_op1_def;
186	0	}
187	0	break;
188	0	case ZEND_ADD_ARRAY_UNPACK:
189	0	var_num = EX_VAR_TO_NUM(opline->result.var);
190	0	if (!zend_bitset_in(def, var_num)) {
191	0	zend_bitset_incl(use, var_num);
192	0	}
193	0	break;
194	0	case ZEND_ADD_ARRAY_ELEMENT:
195	0	var_num = EX_VAR_TO_NUM(opline->result.var);
196	0	if (!zend_bitset_in(def, var_num)) {
197	0	zend_bitset_incl(use, var_num);
198	0	}
199	0	ZEND_FALLTHROUGH;
200	0	case ZEND_INIT_ARRAY:
201	0	if (((build_flags & ZEND_SSA_RC_INFERENCE)
202	0	\|\| (opline->extended_value & ZEND_ARRAY_ELEMENT_REF))
203	0	&& opline->op1_type == IS_CV) {
204	0	goto add_op1_def;
205	0	}
206	0	break;
207	0	case ZEND_YIELD:
208	0	if (opline->op1_type == IS_CV
209	0	&& ((op_array->fn_flags & ZEND_ACC_RETURN_REFERENCE)
210	0	\|\| (build_flags & ZEND_SSA_RC_INFERENCE))) {
211	0	goto add_op1_def;
212	0	}
213	0	break;
214	0	case ZEND_UNSET_CV:
215	0	goto add_op1_def;
216	0	case ZEND_VERIFY_RETURN_TYPE:
217	0	if (opline->op1_type & (IS_TMP_VAR\|IS_VAR\|IS_CV)) {
218	0	goto add_op1_def;
219	0	}
220	0	break;
221	0	case ZEND_FE_FETCH_R:
222	0	case ZEND_FE_FETCH_RW:
223		#if 0
224		/* This special case was handled above the switch */
225		if (opline->op2_type != IS_CV) {
226		op2_use = -1; /* not used */
227		}
228		#endif
229	0	zend_bitset_incl(def, EX_VAR_TO_NUM(opline->op2.var));
230	0	break;
231	0	case ZEND_BIND_LEXICAL:
232	0	if ((opline->extended_value & ZEND_BIND_REF) \|\| (build_flags & ZEND_SSA_RC_INFERENCE)) {
233	0	zend_bitset_incl(def, EX_VAR_TO_NUM(opline->op2.var));
234	0	}
235	0	break;
236	0	default:
237	0	break;
238	0	}
239
240	0	if (opline->result_type & (IS_CV\|IS_VAR\|IS_TMP_VAR)) {
241	0	zend_bitset_incl(def, EX_VAR_TO_NUM(opline->result.var));
242	0	}
243	0	}
244		/* }}} */
245
246		ZEND_API void zend_dfg_add_use_def_op(const zend_op_array op_array, const zend_op opline, uint32_t build_flags, zend_bitset use, zend_bitset def) /* {{{ */
247	0	{
248	0	zend_dfg_add_use_def_op_impl(op_array, opline, build_flags, use, def);
249	0	}
250		/* }}} */
251
252		void zend_build_dfg(const zend_op_array op_array, const zend_cfg cfg, const zend_dfg dfg, uint32_t build_flags) / {{{ */
253	0	{
254	0	uint32_t set_size = dfg->size;
255	0	zend_basic_block *blocks = cfg->blocks;
256	0	int blocks_count = cfg->blocks_count;
257	0	zend_bitset tmp, def, use, in, out;
258	0	int k;
259	0	int j;
260
261	0	tmp = dfg->tmp;
262	0	def = dfg->def;
263	0	use = dfg->use;
264	0	in = dfg->in;
265	0	out = dfg->out;
266
267		/* Collect "def" and "use" sets */
268	0	for (j = 0; j < blocks_count; j++) {
269	0	const zend_op opline, end;
270	0	zend_bitset b_use, b_def;
271
272	0	if ((blocks[j].flags & ZEND_BB_REACHABLE) == 0) {
273	0	continue;
274	0	}
275
276	0	opline = op_array->opcodes + blocks[j].start;
277	0	end = opline + blocks[j].len;
278	0	b_use = DFG_BITSET(use, set_size, j);
279	0	b_def = DFG_BITSET(def, set_size, j);
280	0	for (; opline < end; opline++) {
281	0	if (opline->opcode != ZEND_OP_DATA) {
282	0	zend_dfg_add_use_def_op_impl(op_array, opline, build_flags, b_use, b_def);
283	0	}
284	0	}
285	0	}
286
287		/* Calculate "in" and "out" sets */
288	0	{
289	0	uint32_t worklist_len = zend_bitset_len(blocks_count);
290	0	zend_bitset worklist;
291	0	ALLOCA_FLAG(use_heap);
292	0	worklist = ZEND_BITSET_ALLOCA(worklist_len, use_heap);
293	0	memset(worklist, 0, worklist_len * ZEND_BITSET_ELM_SIZE);
294	0	for (j = 0; j < blocks_count; j++) {
295	0	zend_bitset_incl(worklist, j);
296	0	}
297	0	while (!zend_bitset_empty(worklist, worklist_len)) {
298		/* We use the last block on the worklist, because predecessors tend to be located
299		* before the succeeding block, so this converges faster. */
300	0	j = zend_bitset_last(worklist, worklist_len);
301	0	zend_bitset_excl(worklist, j);
302
303	0	if ((blocks[j].flags & ZEND_BB_REACHABLE) == 0) {
304	0	continue;
305	0	}
306	0	if (blocks[j].successors_count != 0) {
307	0	zend_bitset_copy(DFG_BITSET(out, set_size, j), DFG_BITSET(in, set_size, blocks[j].successors[0]), set_size);
308	0	for (k = 1; k < blocks[j].successors_count; k++) {
309	0	zend_bitset_union(DFG_BITSET(out, set_size, j), DFG_BITSET(in, set_size, blocks[j].successors[k]), set_size);
310	0	}
311	0	} else {
312	0	zend_bitset_clear(DFG_BITSET(out, set_size, j), set_size);
313	0	}
314	0	zend_bitset_union_with_difference(tmp, DFG_BITSET(use, set_size, j), DFG_BITSET(out, set_size, j), DFG_BITSET(def, set_size, j), set_size);
315	0	if (!zend_bitset_equal(DFG_BITSET(in, set_size, j), tmp, set_size)) {
316	0	zend_bitset_copy(DFG_BITSET(in, set_size, j), tmp, set_size);
317
318		/* Add predecessors of changed block to worklist */
319	0	{
320	0	const int *predecessors = &cfg->predecessors[blocks[j].predecessor_offset];
321	0	for (k = 0; k < blocks[j].predecessors_count; k++) {
322	0	zend_bitset_incl(worklist, predecessors[k]);
323	0	}
324	0	}
325	0	}
326	0	}
327
328		free_alloca(worklist, use_heap);
329	0	}
330	0	}
331		/* }}} */