pswalk.c

  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 - 2025, Intel Corp.
  7 *
  8 *****************************************************************************/
  9
 10#include <acpi/acpi.h>
 11#include "accommon.h"
 12#include "acparser.h"
 13
 14#define _COMPONENT          ACPI_PARSER
 15ACPI_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"
 29void 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}