xref: /PHP-5.5/ext/opcache/Optimizer/pass1_5.c (revision d85ac7fb)
1 /* pass 1
2  * - substitute persistent constants (true, false, null, etc)
3  * - perform compile-time evaluation of constant binary and unary operations
4  * - optimize series of ADD_STRING and/or ADD_CHAR
5  * - convert CAST(IS_BOOL,x) into BOOL(x)
6  * - convert INTI_FCALL_BY_NAME, DO_FCALL_BY_NAME into DO_FCALL
7  */
8 
9 if (ZEND_OPTIMIZER_PASS_1 & OPTIMIZATION_LEVEL) {
10 	int i = 0;
11 	zend_op *opline = op_array->opcodes;
12 	zend_op *end = opline + op_array->last;
13 
14 	while (opline < end) {
15 		switch (opline->opcode) {
16 		case ZEND_ADD:
17 		case ZEND_SUB:
18 		case ZEND_MUL:
19 		case ZEND_DIV:
20 		case ZEND_MOD:
21 		case ZEND_SL:
22 		case ZEND_SR:
23 		case ZEND_CONCAT:
24 		case ZEND_IS_EQUAL:
25 		case ZEND_IS_NOT_EQUAL:
26 		case ZEND_IS_SMALLER:
27 		case ZEND_IS_SMALLER_OR_EQUAL:
28 		case ZEND_IS_IDENTICAL:
29 		case ZEND_IS_NOT_IDENTICAL:
30 		case ZEND_BW_OR:
31 		case ZEND_BW_AND:
32 		case ZEND_BW_XOR:
33 		case ZEND_BOOL_XOR:
34 			if (ZEND_OP1_TYPE(opline) == IS_CONST &&
35 				ZEND_OP2_TYPE(opline) == IS_CONST) {
36 				/* binary operation with constant operands */
37 				int (*binary_op)(zval *result, zval *op1, zval *op2 TSRMLS_DC) = get_binary_op(opline->opcode);
38 				zend_uint tv = ZEND_RESULT(opline).var;		/* temporary variable */
39 				zval result;
40 				int er;
41 
42 				if (opline->opcode == ZEND_DIV &&
43 					Z_TYPE(ZEND_OP2_LITERAL(opline)) == IS_LONG &&
44 					Z_LVAL(ZEND_OP2_LITERAL(opline)) == 0) {
45 					/* div by 0 */
46 					break;
47 				}
48 				er = EG(error_reporting);
49 				EG(error_reporting) = 0;
50 				/* evaluate constant expression */
51 				if (binary_op(&result, &ZEND_OP1_LITERAL(opline), &ZEND_OP2_LITERAL(opline) TSRMLS_CC) != SUCCESS) {
52 					EG(error_reporting) = er;
53 					break;
54 				}
55 				EG(error_reporting) = er;
56 				PZ_SET_REFCOUNT_P(&result, 1);
57 				PZ_UNSET_ISREF_P(&result);
58 
59 				literal_dtor(&ZEND_OP1_LITERAL(opline));
60 				literal_dtor(&ZEND_OP2_LITERAL(opline));
61 				MAKE_NOP(opline);
62 
63 				replace_tmp_by_const(op_array, opline + 1, tv, &result TSRMLS_CC);
64 			}
65 			break;
66 
67 		case ZEND_CAST:
68 			if (ZEND_OP1_TYPE(opline) == IS_CONST &&
69 				opline->extended_value != IS_ARRAY &&
70 				opline->extended_value != IS_OBJECT &&
71 				opline->extended_value != IS_RESOURCE) {
72 				/* cast of constant operand */
73 				zend_uint tv = ZEND_RESULT(opline).var;		/* temporary variable */
74 				zval res;
75 				res = ZEND_OP1_LITERAL(opline);
76 				zval_copy_ctor(&res);
77 				switch (opline->extended_value) {
78 					case IS_NULL:
79 						convert_to_null(&res);
80 						break;
81 					case IS_BOOL:
82 						convert_to_boolean(&res);
83 						break;
84 					case IS_LONG:
85 						convert_to_long(&res);
86 						break;
87 					case IS_DOUBLE:
88 						convert_to_double(&res);
89 						break;
90 					case IS_STRING:
91 						convert_to_string(&res);
92 						break;
93 				}
94 
95 				literal_dtor(&ZEND_OP1_LITERAL(opline));
96 				MAKE_NOP(opline);
97 
98 				replace_tmp_by_const(op_array, opline + 1, tv, &res TSRMLS_CC);
99 			} else if (opline->extended_value == IS_BOOL) {
100 				/* T = CAST(X, IS_BOOL) => T = BOOL(X) */
101 				opline->opcode = ZEND_BOOL;
102 				opline->extended_value = 0;
103 			}
104 			break;
105 
106 		case ZEND_BW_NOT:
107 		case ZEND_BOOL_NOT:
108 			if (ZEND_OP1_TYPE(opline) == IS_CONST) {
109 				/* unary operation on constant operand */
110 				unary_op_type unary_op = get_unary_op(opline->opcode);
111 				zval result;
112 				zend_uint tv = ZEND_RESULT(opline).var;		/* temporary variable */
113 				int er;
114 
115 				er = EG(error_reporting);
116 				EG(error_reporting) = 0;
117 #if ZEND_EXTENSION_API_NO < PHP_5_3_X_API_NO
118 				if (unary_op(&result, &ZEND_OP1_LITERAL(opline)) != SUCCESS) {
119 #else
120 				if (unary_op(&result, &ZEND_OP1_LITERAL(opline) TSRMLS_CC) != SUCCESS) {
121 #endif
122 					EG(error_reporting) = er;
123 					break;
124 				}
125 				EG(error_reporting) = er;
126 				PZ_SET_REFCOUNT_P(&result, 1);
127 				PZ_UNSET_ISREF_P(&result);
128 
129 				literal_dtor(&ZEND_OP1_LITERAL(opline));
130 				MAKE_NOP(opline);
131 
132 				replace_tmp_by_const(op_array, opline + 1, tv, &result TSRMLS_CC);
133 			}
134 			break;
135 
136 		case ZEND_ADD_STRING:
137 		case ZEND_ADD_CHAR:
138 			{
139 				zend_op *next_op = opline + 1;
140 				int requires_conversion = (opline->opcode == ZEND_ADD_CHAR? 1 : 0);
141 				size_t final_length = 0;
142 				char *ptr;
143 				zend_op *last_op;
144 
145 				/* There is always a ZEND_RETURN at the end
146 				if (next_op>=end) {
147 					break;
148 				}
149 				*/
150 				while (next_op->opcode == ZEND_ADD_STRING || next_op->opcode == ZEND_ADD_CHAR) {
151 					if (ZEND_RESULT(opline).var != ZEND_RESULT(next_op).var) {
152 						break;
153 					}
154 					if (next_op->opcode == ZEND_ADD_CHAR) {
155 						final_length += 1;
156 					} else { /* ZEND_ADD_STRING */
157 						final_length += ZEND_OP2_LITERAL(next_op).value.str.len;
158 					}
159 					next_op++;
160 				}
161 				if (final_length == 0) {
162 					break;
163 				}
164 				last_op = next_op;
165 				final_length += (requires_conversion? 1 : ZEND_OP2_LITERAL(opline).value.str.len);
166 				ptr = (char *)emalloc(final_length + 1);
167 				ptr[final_length] = '\0';
168 				if (requires_conversion) { /* ZEND_ADD_CHAR */
169 					char chval = (char)ZEND_OP2_LITERAL(opline).value.lval;
170 
171 					ZEND_OP2_LITERAL(opline).value.str.val = ptr;
172 					ptr[0] = chval;
173 					ZEND_OP2_LITERAL(opline).type = IS_STRING;
174 					opline->opcode = ZEND_ADD_STRING;
175 					ptr++;
176 				} else { /* ZEND_ADD_STRING */
177 					memcpy(ptr, Z_STRVAL(ZEND_OP2_LITERAL(opline)), Z_STRLEN(ZEND_OP2_LITERAL(opline)));
178 					if (!IS_INTERNED(Z_STRVAL(ZEND_OP2_LITERAL(opline)))) {
179 						efree(Z_STRVAL(ZEND_OP2_LITERAL(opline)));
180 					}
181 					Z_STRVAL(ZEND_OP2_LITERAL(opline)) = ptr;
182 					ptr += Z_STRLEN(ZEND_OP2_LITERAL(opline));
183 				}
184 				ZEND_OP2_LITERAL(opline).value.str.len = final_length;
185 				next_op = opline + 1;
186 				while (next_op < last_op) {
187 					if (next_op->opcode == ZEND_ADD_STRING) {
188 						memcpy(ptr, ZEND_OP2_LITERAL(next_op).value.str.val, ZEND_OP2_LITERAL(next_op).value.str.len);
189 						ptr += ZEND_OP2_LITERAL(next_op).value.str.len;
190 						literal_dtor(&ZEND_OP2_LITERAL(next_op));
191 					} else { /* ZEND_ADD_CHAR */
192 						*ptr = (char)ZEND_OP2_LITERAL(next_op).value.lval;
193 						ptr++;
194 					}
195 					MAKE_NOP(next_op);
196 					next_op++;
197 				}
198 				if (!((ZEND_OPTIMIZER_PASS_5|ZEND_OPTIMIZER_PASS_10) & OPTIMIZATION_LEVEL)) {
199 					/* NOP removal is disabled => insert JMP over NOPs */
200 					if (last_op-opline >= 3) { /* If we have more than 2 NOPS then JMP over them */
201 						(opline + 1)->opcode = ZEND_JMP;
202 						ZEND_OP1(opline + 1).opline_num = last_op - op_array->opcodes; /* that's OK even for ZE2, since opline_num's are resolved in pass 2 later */
203 					}
204 				}
205 			}
206 			break;
207 
208 		case ZEND_FETCH_CONSTANT:
209 			if (ZEND_OP1_TYPE(opline) == IS_UNUSED &&
210 				ZEND_OP2_TYPE(opline) == IS_CONST &&
211 				Z_TYPE(ZEND_OP2_LITERAL(opline)) == IS_STRING &&
212 				Z_STRLEN(ZEND_OP2_LITERAL(opline)) == sizeof("__COMPILER_HALT_OFFSET__") - 1 &&
213 				memcmp(Z_STRVAL(ZEND_OP2_LITERAL(opline)), "__COMPILER_HALT_OFFSET__", sizeof("__COMPILER_HALT_OFFSET__") - 1) == 0) {
214 				/* substitute __COMPILER_HALT_OFFSET__ constant */
215 				zend_bool orig_in_execution = EG(in_execution);
216 				zend_op_array *orig_op_array = EG(active_op_array);
217 				zval offset;
218 
219 				EG(in_execution) = 1;
220 				EG(active_op_array) = op_array;
221 				if (zend_get_constant("__COMPILER_HALT_OFFSET__", sizeof("__COMPILER_HALT_OFFSET__") - 1, &offset TSRMLS_CC)) {
222 					zend_uint tv = ZEND_RESULT(opline).var;
223 
224 					literal_dtor(&ZEND_OP2_LITERAL(opline));
225 					MAKE_NOP(opline);
226 					replace_tmp_by_const(op_array, opline, tv, &offset TSRMLS_CC);
227 				}
228 				EG(active_op_array) = orig_op_array;
229 				EG(in_execution) = orig_in_execution;
230 				break;
231 			}
232 
233 			if (ZEND_OP1_TYPE(opline) == IS_UNUSED &&
234 				ZEND_OP2_TYPE(opline) == IS_CONST &&
235 				ZEND_OP2_LITERAL(opline).type == IS_STRING) {
236 				/* substitute persistent constants */
237 				zend_uint tv = ZEND_RESULT(opline).var;
238 				zval c;
239 
240 				if (!zend_get_persistent_constant(Z_STRVAL(ZEND_OP2_LITERAL(opline)), Z_STRLEN(ZEND_OP2_LITERAL(opline)), &c, 1 TSRMLS_CC)) {
241 					break;
242 				}
243 				literal_dtor(&ZEND_OP2_LITERAL(opline));
244 				MAKE_NOP(opline);
245 				replace_tmp_by_const(op_array, opline, tv, &c TSRMLS_CC);
246 			}
247 			break;
248 
249 		case ZEND_INIT_FCALL_BY_NAME:
250 			if (opline->extended_value == 0 /* not method */ &&
251 				ZEND_OP1_TYPE(opline) == IS_UNUSED &&
252 				ZEND_OP2_TYPE(opline) == IS_CONST) {
253 				if ((opline + 1)->opcode == ZEND_DO_FCALL_BY_NAME &&
254 					(opline + 1)->extended_value == 0) {
255 					(opline + 1)->opcode = ZEND_DO_FCALL;
256 					COPY_NODE((opline + 1)->op1, opline->op2);
257 					zend_str_tolower(Z_STRVAL(ZEND_OP1_LITERAL(opline + 1)), Z_STRLEN(ZEND_OP1_LITERAL(opline + 1)));
258 #if ZEND_EXTENSION_API_NO > PHP_5_3_X_API_NO
259 					Z_HASH_P(&ZEND_OP1_LITERAL(opline + 1)) = zend_hash_func(Z_STRVAL(ZEND_OP1_LITERAL(opline + 1)), Z_STRLEN(ZEND_OP1_LITERAL(opline + 1)) + 1);
260 					op_array->literals[(opline + 1)->op1.constant].cache_slot = op_array->last_cache_slot++;
261 #endif
262 					MAKE_NOP(opline);
263 				}
264 			}
265 			break;
266 
267 #if ZEND_EXTENSION_API_NO >= PHP_5_5_X_API_NO
268 		case ZEND_FETCH_R:
269 		case ZEND_FETCH_W:
270 		case ZEND_FETCH_RW:
271 		case ZEND_FETCH_FUNC_ARG:
272 		case ZEND_FETCH_IS:
273 		case ZEND_FETCH_UNSET:
274 			if (opline != op_array->opcodes &&
275 			    (opline-1)->opcode == ZEND_BEGIN_SILENCE &&
276 			    (opline->extended_value & ZEND_FETCH_TYPE_MASK) == ZEND_FETCH_LOCAL &&
277 				opline->op1_type == IS_CONST &&
278 			    opline->op2_type == IS_UNUSED &&
279 			    Z_TYPE(ZEND_OP1_LITERAL(opline)) == IS_STRING &&
280 			    (Z_STRLEN(ZEND_OP1_LITERAL(opline)) != sizeof("this")-1 ||
281 			     memcmp(Z_STRVAL(ZEND_OP1_LITERAL(opline)), "this", sizeof("this")) != 0)) {
282 
283 			    int var = opline->result.var;
284 			    int level = 0;
285 				zend_op *op = opline + 1;
286 				zend_op *use = NULL;
287 
288 				while (op < end) {
289 					if (op->opcode == ZEND_BEGIN_SILENCE) {
290 						level++;
291 					} else if (op->opcode == ZEND_END_SILENCE) {
292 						if (level == 0) {
293 							break;
294 						} else {
295 							level--;
296 						}
297 					}
298 					if (op->op1_type == IS_VAR && op->op1.var == var) {
299 						if (use) {
300 							/* used more than once */
301 							use = NULL;
302 							break;
303 						}
304 						use = op;
305 					} else if (op->op2_type == IS_VAR && op->op2.var == var) {
306 						if (use) {
307 							/* used more than once */
308 							use = NULL;
309 							break;
310 						}
311 						use = op;
312 					}
313 					op++;
314 				}
315 				if (use) {
316 					if (use->op1_type == IS_VAR && use->op1.var == var) {
317 						use->op1_type = IS_CV;
318 						use->op1.var = zend_optimizer_lookup_cv(op_array,
319 							Z_STRVAL(ZEND_OP1_LITERAL(opline)),
320 							Z_STRLEN(ZEND_OP1_LITERAL(opline)));
321 						MAKE_NOP(opline);
322 					} else if (use->op2_type == IS_VAR && use->op2.var == var) {
323 						use->op2_type = IS_CV;
324 						use->op2.var = zend_optimizer_lookup_cv(op_array,
325 							Z_STRVAL(ZEND_OP1_LITERAL(opline)),
326 							Z_STRLEN(ZEND_OP1_LITERAL(opline)));
327 						MAKE_NOP(opline);
328 					}
329 				}
330 			}
331 			break;
332 #endif
333 
334 		}
335 		opline++;
336 		i++;
337 	}
338 }
339