1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3 *
4 * Module Name: pswalk - Parser routines to walk parsed op tree(s)
5 *
6 * Copyright (C) 2000 - 2020, Intel Corp.
7 *
8 *****************************************************************************/
9
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "acparser.h"
13
14 #define _COMPONENT ACPI_PARSER
15 ACPI_MODULE_NAME("pswalk")
16
17 /*******************************************************************************
18 *
19 * FUNCTION: acpi_ps_delete_parse_tree
20 *
21 * PARAMETERS: subtree_root - Root of tree (or subtree) to delete
22 *
23 * RETURN: None
24 *
25 * DESCRIPTION: Delete a portion of or an entire parse tree.
26 *
27 ******************************************************************************/
28 #include "amlcode.h"
acpi_ps_delete_parse_tree(union acpi_parse_object * subtree_root)29 void acpi_ps_delete_parse_tree(union acpi_parse_object *subtree_root)
30 {
31 union acpi_parse_object *op = subtree_root;
32 union acpi_parse_object *next = NULL;
33 union acpi_parse_object *parent = NULL;
34 u32 level = 0;
35
36 ACPI_FUNCTION_TRACE_PTR(ps_delete_parse_tree, subtree_root);
37
38 ACPI_DEBUG_PRINT((ACPI_DB_PARSE_TREES, " root %p\n", subtree_root));
39
40 /* Visit all nodes in the subtree */
41
42 while (op) {
43 if (op != parent) {
44
45 /* This is the descending case */
46
47 if (ACPI_IS_DEBUG_ENABLED
48 (ACPI_LV_PARSE_TREES, _COMPONENT)) {
49
50 /* This debug option will print the entire parse tree */
51
52 acpi_os_printf(" %*.s%s %p", (level * 4),
53 " ",
54 acpi_ps_get_opcode_name(op->
55 common.
56 aml_opcode),
57 op);
58
59 if (op->named.aml_opcode == AML_INT_NAMEPATH_OP) {
60 acpi_os_printf(" %4.4s",
61 op->common.value.string);
62 }
63 if (op->named.aml_opcode == AML_STRING_OP) {
64 acpi_os_printf(" %s",
65 op->common.value.string);
66 }
67 acpi_os_printf("\n");
68 }
69
70 /* Look for an argument or child of the current op */
71
72 next = acpi_ps_get_arg(op, 0);
73 if (next) {
74
75 /* Still going downward in tree (Op is not completed yet) */
76
77 op = next;
78 level++;
79 continue;
80 }
81 }
82
83 /* No more children, this Op is complete. */
84
85 next = op->common.next;
86 parent = op->common.parent;
87
88 acpi_ps_free_op(op);
89
90 /* If we are back to the starting point, the walk is complete. */
91
92 if (op == subtree_root) {
93 return_VOID;
94 }
95
96 if (next) {
97 op = next;
98 } else {
99 level--;
100 op = parent;
101 }
102 }
103
104 return_VOID;
105 }
106
