Apply obvious simplification

Author: bwoebi

NEWS

@@ -30,6 +30,8 @@ PHP                                                                        NEWS
   . Fixed bug GH-14267 (opcache.jit=off does not allow enabling JIT at runtime).
     (ilutov)
   . Fixed TLS access in JIT on FreeBSD/amd64. (Arnaud)
+  . Fixed bug GH-13817 (Segmentation fault for enabled observers after pass 4).
+    (Bob)
 
 - Soap:
   . Fixed bug #47925 (PHPClient can't decompress response). (nielsdos)
@@ -142,8 +144,6 @@ PHP                                                                        NEWS
 - Opcache:
   . Fixed incorrect assumptions across compilation units for static calls.
     (ilutov)
-  . Fixed bug GH-13817 (Segmentation fault for enabled observers after pass 4).
-    (Bob)
 
 - OpenSSL:
   . Fixed bug GH-10495 (feof on OpenSSL stream hangs indefinitely).

Zend/Optimizer/compact_vars.c

@@ -117,7 +117,7 @@ void zend_optimizer_compact_vars(zend_op_array *op_array) {
 		op_array->last_var = num_cvs;
 	}
 
-	op_array->T = num_tmps;
+	op_array->T = num_tmps + ZEND_OBSERVER_ENABLED; // reserve last temporary for observers if enabled
 
 	free_alloca(vars_map, use_heap2);
 }

Zend/Optimizer/optimize_func_calls.c

@@ -195,15 +195,15 @@ void zend_optimize_func_calls(zend_op_array *op_array, zend_optimizer_ctx *ctx)
 						/* nothing to do */
 					} else if (fcall->opcode == ZEND_INIT_FCALL_BY_NAME) {
 						fcall->opcode = ZEND_INIT_FCALL;
-						fcall->op1.num = zend_vm_calc_ct_used_stack(fcall->extended_value, call_stack[call].func);
+						fcall->op1.num = zend_vm_calc_used_stack(fcall->extended_value, call_stack[call].func);
 						literal_dtor(&ZEND_OP2_LITERAL(fcall));
 						fcall->op2.constant = fcall->op2.constant + 1;
 						if (opline->opcode != ZEND_CALLABLE_CONVERT) {
 							opline->opcode = zend_get_call_op(fcall, call_stack[call].func);
 						}
 					} else if (fcall->opcode == ZEND_INIT_NS_FCALL_BY_NAME) {
 						fcall->opcode = ZEND_INIT_FCALL;
-						fcall->op1.num = zend_vm_calc_ct_used_stack(fcall->extended_value, call_stack[call].func);
+						fcall->op1.num = zend_vm_calc_used_stack(fcall->extended_value, call_stack[call].func);
 						literal_dtor(&op_array->literals[fcall->op2.constant]);
 						literal_dtor(&op_array->literals[fcall->op2.constant + 2]);
 						fcall->op2.constant = fcall->op2.constant + 1;

Zend/Optimizer/optimize_temp_vars_5.c

@@ -173,5 +173,5 @@ void zend_optimize_temporary_variables(zend_op_array *op_array, zend_optimizer_c
 	}
 
 	zend_arena_release(&ctx->arena, checkpoint);
-	op_array->T = max + 1;
+	op_array->T = max + 1 + ZEND_OBSERVER_ENABLED; // reserve last temporary for observers if enabled
 }

Zend/Optimizer/zend_optimizer.c

@@ -1097,8 +1097,6 @@ static void zend_revert_pass_two(zend_op_array *op_array)
 	}
 #endif
 
-	op_array->T -= ZEND_OBSERVER_ENABLED;
-
 	op_array->fn_flags &= ~ZEND_ACC_DONE_PASS_TWO;
 }
 
@@ -1128,8 +1126,6 @@ static void zend_redo_pass_two(zend_op_array *op_array)
 	}
 #endif
 
-	op_array->T += ZEND_OBSERVER_ENABLED; // reserve last temporary for observers if enabled
-
 	opline = op_array->opcodes;
 	end = opline + op_array->last;
 	while (opline < end) {
@@ -1238,8 +1234,6 @@ static void zend_redo_pass_two_ex(zend_op_array *op_array, zend_ssa *ssa)
 	}
 #endif
 
-	op_array->T += ZEND_OBSERVER_ENABLED; // reserve last temporary for observers if enabled
-
 	opline = op_array->opcodes;
 	end = opline + op_array->last;
 	while (opline < end) {
@@ -1364,7 +1358,7 @@ static void zend_adjust_fcall_stack_size(zend_op_array *op_array, zend_optimizer
 				&ctx->script->function_table,
 				Z_STR_P(RT_CONSTANT(opline, opline->op2)));
 			if (func) {
-				opline->op1.num = zend_vm_calc_ct_used_stack(opline->extended_value, func);
+				opline->op1.num = zend_vm_calc_used_stack(opline->extended_value, func);
 			}
 		}
 		opline++;
@@ -1383,7 +1377,7 @@ static void zend_adjust_fcall_stack_size_graph(zend_op_array *op_array)
 
 			if (opline && call_info->callee_func && opline->opcode == ZEND_INIT_FCALL) {
 				ZEND_ASSERT(!call_info->is_prototype);
-				opline->op1.num = zend_vm_calc_ct_used_stack(opline->extended_value, call_info->callee_func);
+				opline->op1.num = zend_vm_calc_used_stack(opline->extended_value, call_info->callee_func);
 			}
 			call_info = call_info->next_callee;
 		}

Zend/zend_execute.c

@@ -226,11 +226,6 @@ ZEND_API void* zend_vm_stack_extend(size_t size)
 	return ptr;
 }
 
-ZEND_API uint32_t zend_vm_calc_ct_used_stack(uint32_t num_args, zend_function *func)
-{
-	return zend_vm_calc_used_stack(num_args, func) + ((func->common.fn_flags & ZEND_ACC_DONE_PASS_TWO) == 0 && ZEND_USER_CODE(func->type) ? ZEND_OBSERVER_ENABLED : 0) * sizeof(zval);
-}
-
 ZEND_API zval* zend_get_compiled_variable_value(const zend_execute_data *execute_data, uint32_t var)
 {
 	return EX_VAR(var);

Zend/zend_execute.h

@@ -255,9 +255,6 @@ static zend_always_inline uint32_t zend_vm_calc_used_stack(uint32_t num_args, ze
 	return used_stack * sizeof(zval);
 }
 
-// Handle a possibly currently not applied pass_two
-ZEND_API uint32_t zend_vm_calc_ct_used_stack(uint32_t num_args, zend_function *func);
-
 static zend_always_inline zend_execute_data *zend_vm_stack_push_call_frame(uint32_t call_info, zend_function *func, uint32_t num_args, void *object_or_called_scope)
 {
 	uint32_t used_stack = zend_vm_calc_used_stack(num_args, func);