dist/compiler/aslprune.c

/******************************************************************************
 *
 * Module Name: aslprune - Parse tree prune utility
 *
 *****************************************************************************/

/******************************************************************************
 *
 * 1. Copyright Notice
 *
 * Some or all of this work - Copyright (c) 1999 - 2025, Intel Corp.
 * All rights reserved.
 *
 * 2. License
 *
 * 2.1. This is your license from Intel Corp. under its intellectual property
 * rights. You may have additional license terms from the party that provided
 * you this software, covering your right to use that party's intellectual
 * property rights.
 *
 * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
 * copy of the source code appearing in this file ("Covered Code") an
 * irrevocable, perpetual, worldwide license under Intel's copyrights in the
 * base code distributed originally by Intel ("Original Intel Code") to copy,
 * make derivatives, distribute, use and display any portion of the Covered
 * Code in any form, with the right to sublicense such rights; and
 *
 * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
 * license (with the right to sublicense), under only those claims of Intel
 * patents that are infringed by the Original Intel Code, to make, use, sell,
 * offer to sell, and import the Covered Code and derivative works thereof
 * solely to the minimum extent necessary to exercise the above copyright
 * license, and in no event shall the patent license extend to any additions
 * to or modifications of the Original Intel Code. No other license or right
 * is granted directly or by implication, estoppel or otherwise;
 *
 * The above copyright and patent license is granted only if the following
 * conditions are met:
 *
 * 3. Conditions
 *
 * 3.1. Redistribution of Source with Rights to Further Distribute Source.
 * Redistribution of source code of any substantial portion of the Covered
 * Code or modification with rights to further distribute source must include
 * the above Copyright Notice, the above License, this list of Conditions,
 * and the following Disclaimer and Export Compliance provision. In addition,
 * Licensee must cause all Covered Code to which Licensee contributes to
 * contain a file documenting the changes Licensee made to create that Covered
 * Code and the date of any change. Licensee must include in that file the
 * documentation of any changes made by any predecessor Licensee. Licensee
 * must include a prominent statement that the modification is derived,
 * directly or indirectly, from Original Intel Code.
 *
 * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
 * Redistribution of source code of any substantial portion of the Covered
 * Code or modification without rights to further distribute source must
 * include the following Disclaimer and Export Compliance provision in the
 * documentation and/or other materials provided with distribution. In
 * addition, Licensee may not authorize further sublicense of source of any
 * portion of the Covered Code, and must include terms to the effect that the
 * license from Licensee to its licensee is limited to the intellectual
 * property embodied in the software Licensee provides to its licensee, and
 * not to intellectual property embodied in modifications its licensee may
 * make.
 *
 * 3.3. Redistribution of Executable. Redistribution in executable form of any
 * substantial portion of the Covered Code or modification must reproduce the
 * above Copyright Notice, and the following Disclaimer and Export Compliance
 * provision in the documentation and/or other materials provided with the
 * distribution.
 *
 * 3.4. Intel retains all right, title, and interest in and to the Original
 * Intel Code.
 *
 * 3.5. Neither the name Intel nor any other trademark owned or controlled by
 * Intel shall be used in advertising or otherwise to promote the sale, use or
 * other dealings in products derived from or relating to the Covered Code
 * without prior written authorization from Intel.
 *
 * 4. Disclaimer and Export Compliance
 *
 * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
 * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
 * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
 * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
 * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
 * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
 * PARTICULAR PURPOSE.
 *
 * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
 * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
 * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
 * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
 * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
 * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
 * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
 * LIMITED REMEDY.
 *
 * 4.3. Licensee shall not export, either directly or indirectly, any of this
 * software or system incorporating such software without first obtaining any
 * required license or other approval from the U. S. Department of Commerce or
 * any other agency or department of the United States Government. In the
 * event Licensee exports any such software from the United States or
 * re-exports any such software from a foreign destination, Licensee shall
 * ensure that the distribution and export/re-export of the software is in
 * compliance with all laws, regulations, orders, or other restrictions of the
 * U.S. Export Administration Regulations. Licensee agrees that neither it nor
 * any of its subsidiaries will export/re-export any technical data, process,
 * software, or service, directly or indirectly, to any country for which the
 * United States government or any agency thereof requires an export license,
 * other governmental approval, or letter of assurance, without first obtaining
 * such license, approval or letter.
 *
 *****************************************************************************
 *
 * Alternatively, you may choose to be licensed under the terms of the
 * following license:
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Alternatively, you may choose to be licensed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 *****************************************************************************/

#include "aslcompiler.h"
#include "aslcompiler.y.h"
#include "acapps.h"

#define _COMPONENT          ACPI_COMPILER
        ACPI_MODULE_NAME    ("aslprune")


/* Local prototypes */

static ACPI_STATUS
PrTreePruneWalk (
    ACPI_PARSE_OBJECT       *Op,
    UINT32                  Level,
    void                    *Context);

static void
PrPrintObjectAtLevel (
    UINT32                  Level,
    const char              *ObjectName);


/* Structure used for the pruning parse tree walk */

typedef struct acpi_prune_info
{
    UINT32                  PruneLevel;
    UINT16                  ParseOpcode;
    UINT16                  Count;

} ACPI_PRUNE_INFO;


/*******************************************************************************
 *
 * FUNCTION:    AslPruneParseTree
 *
 * PARAMETERS:  PruneDepth              - Number of levels to prune
 *              Type                    - Prune type (Device, Method, etc.)
 *
 * RETURN:      None
 *
 * DESCRIPTION: Prune off one or more levels of the ASL parse tree
 *
 ******************************************************************************/

void
AslPruneParseTree (
    UINT32                  PruneDepth,
    UINT32                  Type)
{
    ACPI_PRUNE_INFO         PruneObj;


    PruneObj.PruneLevel = PruneDepth;
    PruneObj.Count = 0;

    switch (Type)
    {
    case 0:
        PruneObj.ParseOpcode = (UINT16) PARSEOP_DEVICE;
        break;

    case 1:
        PruneObj.ParseOpcode = (UINT16) PARSEOP_METHOD;
        break;

    case 2:
        PruneObj.ParseOpcode = (UINT16) PARSEOP_IF;
        break;

    default:
        AcpiOsPrintf ("Unsupported type: %u\n", Type);
        return;
    }

    AcpiOsPrintf ("Pruning parse tree, from depth %u\n",
        PruneDepth);

    AcpiOsPrintf ("\nRemoving Objects:\n");

    TrWalkParseTree (AslGbl_ParseTreeRoot, ASL_WALK_VISIT_DOWNWARD,
        PrTreePruneWalk, NULL, ACPI_CAST_PTR (void, &PruneObj));

    AcpiOsPrintf ("\n%u Total Objects Removed\n", PruneObj.Count);
}


/*******************************************************************************
 *
 * FUNCTION:    PrPrintObjectAtLevel
 *
 * PARAMETERS:  Level                   - Current nesting level
 *              ObjectName              - ACPI name for the object
 *
 * RETURN:      None
 *
 * DESCRIPTION: Print object name with indent
 *
 ******************************************************************************/

static void
PrPrintObjectAtLevel (
    UINT32                  Level,
    const char              *ObjectName)
{
    UINT32                  i;


    for (i = 0; i < Level; i++)
    {
        AcpiOsPrintf ("  ");
    }

    AcpiOsPrintf ("[%s] at Level [%u]\n", ObjectName, Level);
}


/*******************************************************************************
 *
 * FUNCTION:    PrTreePruneWalk
 *
 * PARAMETERS:  Parse tree walk callback
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Prune off one or more levels of the ASL parse tree
 *
 * Current objects that can be pruned are: Devices, Methods, and If/Else
 * blocks.
 *
 ******************************************************************************/

static ACPI_STATUS
PrTreePruneWalk (
    ACPI_PARSE_OBJECT       *Op,
    UINT32                  Level,
    void                    *Context)
{
    ACPI_PRUNE_INFO         *PruneObj = (ACPI_PRUNE_INFO *) Context;


    /* We only care about objects below the Prune Level threshold */

    if (Level <= PruneObj->PruneLevel)
    {
        return (AE_OK);
    }

    if ((Op->Asl.ParseOpcode != PruneObj->ParseOpcode) &&
       !(Op->Asl.ParseOpcode == PARSEOP_ELSE &&
             PruneObj->ParseOpcode == PARSEOP_IF))
    {
        return (AE_OK);
    }

    switch (Op->Asl.ParseOpcode)
    {
    case PARSEOP_METHOD:

        AcpiOsPrintf ("Method");
        PrPrintObjectAtLevel (Level, Op->Asl.Child->Asl.Value.Name);
        Op->Asl.Child->Asl.Next->Asl.Next->Asl.Next->Asl.Next->Asl.Next->Asl.Next = NULL;
        PruneObj->Count++;
        break;

    case PARSEOP_DEVICE:

        AcpiOsPrintf ("Device");
        PrPrintObjectAtLevel (Level, Op->Asl.Child->Asl.Value.Name);
        Op->Asl.Child->Asl.Next = NULL;
        PruneObj->Count++;
        break;

    case PARSEOP_IF:
    case PARSEOP_ELSE:

        if (Op->Asl.ParseOpcode == PARSEOP_ELSE)
        {
            PrPrintObjectAtLevel(Level, "Else");
            Op->Asl.Child = NULL;
        }
        else
        {
            PrPrintObjectAtLevel(Level, "If");
            Op->Asl.Child->Asl.Next = NULL;
        }

        PruneObj->Count++;
        break;

    default:

        break;
    }

    return (AE_OK);
}