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asltransform.c revision 1.1.1.14
      1 /******************************************************************************
      2  *
      3  * Module Name: asltransform - Parse tree transforms
      4  *
      5  *****************************************************************************/
      6 
      7 /*
      8  * Copyright (C) 2000 - 2019, Intel Corp.
      9  * All rights reserved.
     10  *
     11  * Redistribution and use in source and binary forms, with or without
     12  * modification, are permitted provided that the following conditions
     13  * are met:
     14  * 1. Redistributions of source code must retain the above copyright
     15  *    notice, this list of conditions, and the following disclaimer,
     16  *    without modification.
     17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
     18  *    substantially similar to the "NO WARRANTY" disclaimer below
     19  *    ("Disclaimer") and any redistribution must be conditioned upon
     20  *    including a substantially similar Disclaimer requirement for further
     21  *    binary redistribution.
     22  * 3. Neither the names of the above-listed copyright holders nor the names
     23  *    of any contributors may be used to endorse or promote products derived
     24  *    from this software without specific prior written permission.
     25  *
     26  * Alternatively, this software may be distributed under the terms of the
     27  * GNU General Public License ("GPL") version 2 as published by the Free
     28  * Software Foundation.
     29  *
     30  * NO WARRANTY
     31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
     34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
     39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
     40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     41  * POSSIBILITY OF SUCH DAMAGES.
     42  */
     43 
     44 #include "aslcompiler.h"
     45 #include "aslcompiler.y.h"
     46 
     47 #define _COMPONENT          ACPI_COMPILER
     48         ACPI_MODULE_NAME    ("asltransform")
     49 
     50 /* Local prototypes */
     51 
     52 static void
     53 TrTransformSubtree (
     54     ACPI_PARSE_OBJECT       *Op);
     55 
     56 static char *
     57 TrAmlGetNextTempName (
     58     ACPI_PARSE_OBJECT       *Op,
     59     UINT8                   *TempCount);
     60 
     61 static void
     62 TrAmlInitLineNumbers (
     63     ACPI_PARSE_OBJECT       *Op,
     64     ACPI_PARSE_OBJECT       *Neighbor);
     65 
     66 static void
     67 TrAmlInitNode (
     68     ACPI_PARSE_OBJECT       *Op,
     69     UINT16                  ParseOpcode);
     70 
     71 static void
     72 TrAmlSetSubtreeParent (
     73     ACPI_PARSE_OBJECT       *Op,
     74     ACPI_PARSE_OBJECT       *Parent);
     75 
     76 static void
     77 TrAmlInsertPeer (
     78     ACPI_PARSE_OBJECT       *Op,
     79     ACPI_PARSE_OBJECT       *NewPeer);
     80 
     81 static void
     82 TrDoDefinitionBlock (
     83     ACPI_PARSE_OBJECT       *Op);
     84 
     85 static void
     86 TrDoSwitch (
     87     ACPI_PARSE_OBJECT       *StartNode);
     88 
     89 
     90 /*******************************************************************************
     91  *
     92  * FUNCTION:    TrAmlGetNextTempName
     93  *
     94  * PARAMETERS:  Op              - Current parse op
     95  *              TempCount       - Current temporary counter. Was originally
     96  *                                per-module; Currently per method, could be
     97  *                                expanded to per-scope.
     98  *
     99  * RETURN:      A pointer to name (allocated here).
    100  *
    101  * DESCRIPTION: Generate an ACPI name of the form _T_x. These names are
    102  *              reserved for use by the ASL compiler. (_T_0 through _T_Z)
    103  *
    104  ******************************************************************************/
    105 
    106 static char *
    107 TrAmlGetNextTempName (
    108     ACPI_PARSE_OBJECT       *Op,
    109     UINT8                   *TempCount)
    110 {
    111     char                    *TempName;
    112 
    113 
    114     if (*TempCount >= (10 + 26))  /* 0-35 valid: 0-9 and A-Z for TempName[3] */
    115     {
    116         /* Too many temps */
    117 
    118         AslError (ASL_ERROR, ASL_MSG_TOO_MANY_TEMPS, Op, NULL);
    119         return (NULL);
    120     }
    121 
    122     TempName = UtLocalCalloc (5);
    123 
    124     if (*TempCount < 10)    /* 0-9 */
    125     {
    126         TempName[3] = (char) (*TempCount + '0');
    127     }
    128     else                    /* 10-35: A-Z */
    129     {
    130         TempName[3] = (char) (*TempCount + ('A' - 10));
    131     }
    132 
    133     (*TempCount)++;
    134 
    135     /* First three characters are always "_T_" */
    136 
    137     TempName[0] = '_';
    138     TempName[1] = 'T';
    139     TempName[2] = '_';
    140 
    141     return (TempName);
    142 }
    143 
    144 
    145 /*******************************************************************************
    146  *
    147  * FUNCTION:    TrAmlInitLineNumbers
    148  *
    149  * PARAMETERS:  Op              - Op to be initialized
    150  *              Neighbor        - Op used for initialization values
    151  *
    152  * RETURN:      None
    153  *
    154  * DESCRIPTION: Initialized the various line numbers for a parse node.
    155  *
    156  ******************************************************************************/
    157 
    158 static void
    159 TrAmlInitLineNumbers (
    160     ACPI_PARSE_OBJECT       *Op,
    161     ACPI_PARSE_OBJECT       *Neighbor)
    162 {
    163 
    164     Op->Asl.EndLine           = Neighbor->Asl.EndLine;
    165     Op->Asl.EndLogicalLine    = Neighbor->Asl.EndLogicalLine;
    166     Op->Asl.LineNumber        = Neighbor->Asl.LineNumber;
    167     Op->Asl.LogicalByteOffset = Neighbor->Asl.LogicalByteOffset;
    168     Op->Asl.LogicalLineNumber = Neighbor->Asl.LogicalLineNumber;
    169 }
    170 
    171 
    172 /*******************************************************************************
    173  *
    174  * FUNCTION:    TrAmlInitNode
    175  *
    176  * PARAMETERS:  Op              - Op to be initialized
    177  *              ParseOpcode     - Opcode for this node
    178  *
    179  * RETURN:      None
    180  *
    181  * DESCRIPTION: Initialize a node with the parse opcode and opcode name.
    182  *
    183  ******************************************************************************/
    184 
    185 static void
    186 TrAmlInitNode (
    187     ACPI_PARSE_OBJECT       *Op,
    188     UINT16                  ParseOpcode)
    189 {
    190 
    191     Op->Asl.ParseOpcode = ParseOpcode;
    192     UtSetParseOpName (Op);
    193 }
    194 
    195 
    196 /*******************************************************************************
    197  *
    198  * FUNCTION:    TrAmlSetSubtreeParent
    199  *
    200  * PARAMETERS:  Op              - First node in a list of peer nodes
    201  *              Parent          - Parent of the subtree
    202  *
    203  * RETURN:      None
    204  *
    205  * DESCRIPTION: Set the parent for all peer nodes in a subtree
    206  *
    207  ******************************************************************************/
    208 
    209 static void
    210 TrAmlSetSubtreeParent (
    211     ACPI_PARSE_OBJECT       *Op,
    212     ACPI_PARSE_OBJECT       *Parent)
    213 {
    214     ACPI_PARSE_OBJECT       *Next;
    215 
    216 
    217     Next = Op;
    218     while (Next)
    219     {
    220         Next->Asl.Parent = Parent;
    221         Next = Next->Asl.Next;
    222     }
    223 }
    224 
    225 
    226 /*******************************************************************************
    227  *
    228  * FUNCTION:    TrAmlInsertPeer
    229  *
    230  * PARAMETERS:  Op              - First node in a list of peer nodes
    231  *              NewPeer         - Peer node to insert
    232  *
    233  * RETURN:      None
    234  *
    235  * DESCRIPTION: Insert a new peer node into a list of peers.
    236  *
    237  ******************************************************************************/
    238 
    239 static void
    240 TrAmlInsertPeer (
    241     ACPI_PARSE_OBJECT       *Op,
    242     ACPI_PARSE_OBJECT       *NewPeer)
    243 {
    244 
    245     NewPeer->Asl.Next = Op->Asl.Next;
    246     Op->Asl.Next = NewPeer;
    247 }
    248 
    249 
    250 /*******************************************************************************
    251  *
    252  * FUNCTION:    TrAmlTransformWalkBegin
    253  *
    254  * PARAMETERS:  ASL_WALK_CALLBACK
    255  *
    256  * RETURN:      None
    257  *
    258  * DESCRIPTION: Parse tree walk to generate both the AML opcodes and the AML
    259  *              operands.
    260  *
    261  ******************************************************************************/
    262 
    263 ACPI_STATUS
    264 TrAmlTransformWalkBegin (
    265     ACPI_PARSE_OBJECT       *Op,
    266     UINT32                  Level,
    267     void                    *Context)
    268 {
    269 
    270     TrTransformSubtree (Op);
    271     return (AE_OK);
    272 }
    273 
    274 
    275 /*******************************************************************************
    276  *
    277  * FUNCTION:    TrAmlTransformWalkEnd
    278  *
    279  * PARAMETERS:  ASL_WALK_CALLBACK
    280  *
    281  * RETURN:      None
    282  *
    283  * DESCRIPTION: Parse tree walk to generate both the AML opcodes and the AML
    284  *              operands.
    285  *
    286  ******************************************************************************/
    287 
    288 ACPI_STATUS
    289 TrAmlTransformWalkEnd (
    290     ACPI_PARSE_OBJECT       *Op,
    291     UINT32                  Level,
    292     void                    *Context)
    293 {
    294 
    295     /* Save possible Externals list in the DefintionBlock Op */
    296 
    297     if (Op->Asl.ParseOpcode == PARSEOP_DEFINITION_BLOCK)
    298     {
    299         Op->Asl.Value.Arg = AslGbl_ExternalsListHead;
    300         AslGbl_ExternalsListHead = NULL;
    301     }
    302 
    303     return (AE_OK);
    304 }
    305 
    306 
    307 /*******************************************************************************
    308  *
    309  * FUNCTION:    TrTransformSubtree
    310  *
    311  * PARAMETERS:  Op        - The parent parse node
    312  *
    313  * RETURN:      None
    314  *
    315  * DESCRIPTION: Prepare nodes to be output as AML data and operands. The more
    316  *              complex AML opcodes require processing of the child nodes
    317  *              (arguments/operands).
    318  *
    319  ******************************************************************************/
    320 
    321 static void
    322 TrTransformSubtree (
    323     ACPI_PARSE_OBJECT           *Op)
    324 {
    325     ACPI_PARSE_OBJECT           *MethodOp;
    326 
    327 
    328     if (Op->Asl.AmlOpcode == AML_RAW_DATA_BYTE)
    329     {
    330         return;
    331     }
    332 
    333     switch (Op->Asl.ParseOpcode)
    334     {
    335     case PARSEOP_DEFINITION_BLOCK:
    336 
    337         TrDoDefinitionBlock (Op);
    338         break;
    339 
    340     case PARSEOP_SWITCH:
    341 
    342         TrDoSwitch (Op);
    343         break;
    344 
    345     case PARSEOP_METHOD:
    346         /*
    347          * TBD: Zero the tempname (_T_x) count. Probably shouldn't be a global,
    348          * however
    349          */
    350         AslGbl_TempCount = 0;
    351         break;
    352 
    353     case PARSEOP_EXTERNAL:
    354 
    355         ExDoExternal (Op);
    356         break;
    357 
    358     case PARSEOP___METHOD__:
    359 
    360         /* Transform to a string op containing the parent method name */
    361 
    362         Op->Asl.ParseOpcode = PARSEOP_STRING_LITERAL;
    363         UtSetParseOpName (Op);
    364 
    365         /* Find the parent control method op */
    366 
    367         MethodOp = Op;
    368         while (MethodOp)
    369         {
    370             if (MethodOp->Asl.ParseOpcode == PARSEOP_METHOD)
    371             {
    372                 /* First child contains the method name */
    373 
    374                 MethodOp = MethodOp->Asl.Child;
    375                 Op->Asl.Value.String = MethodOp->Asl.Value.String;
    376                 return;
    377             }
    378 
    379             MethodOp = MethodOp->Asl.Parent;
    380         }
    381 
    382         /* At the root, invocation not within a control method */
    383 
    384         Op->Asl.Value.String = "\\";
    385         break;
    386 
    387     case PARSEOP_UNLOAD:
    388 
    389         AslError (ASL_WARNING, ASL_MSG_UNLOAD, Op, NULL);
    390         break;
    391 
    392     case PARSEOP_SLEEP:
    393 
    394         /* Remark for very long sleep values */
    395 
    396         if (Op->Asl.Child->Asl.Value.Integer > 1000)
    397         {
    398             AslError (ASL_REMARK, ASL_MSG_LONG_SLEEP, Op, NULL);
    399         }
    400         break;
    401 
    402     case PARSEOP_PROCESSOR:
    403 
    404         AslError (ASL_WARNING, ASL_MSG_LEGACY_PROCESSOR_OP, Op, Op->Asl.ExternalName);
    405 
    406         break;
    407 
    408     default:
    409 
    410         /* Nothing to do here for other opcodes */
    411 
    412         break;
    413     }
    414 }
    415 
    416 
    417 /*******************************************************************************
    418  *
    419  * FUNCTION:    TrDoDefinitionBlock
    420  *
    421  * PARAMETERS:  Op        - Parse node
    422  *
    423  * RETURN:      None
    424  *
    425  * DESCRIPTION: Find the end of the definition block and set a global to this
    426  *              node. It is used by the compiler to insert compiler-generated
    427  *              names at the root level of the namespace.
    428  *
    429  ******************************************************************************/
    430 
    431 static void
    432 TrDoDefinitionBlock (
    433     ACPI_PARSE_OBJECT       *Op)
    434 {
    435     ACPI_PARSE_OBJECT       *Next;
    436     UINT32                  i;
    437 
    438 
    439     /* Reset external list when starting a definition block */
    440 
    441     AslGbl_ExternalsListHead = NULL;
    442 
    443     Next = Op->Asl.Child;
    444     for (i = 0; i < 5; i++)
    445     {
    446         Next = Next->Asl.Next;
    447         if (i == 0)
    448         {
    449             /*
    450              * This is the table signature. Only the DSDT can be assumed
    451              * to be at the root of the namespace;  Therefore, namepath
    452              * optimization can only be performed on the DSDT.
    453              */
    454             if (!ACPI_COMPARE_NAMESEG (Next->Asl.Value.String, ACPI_SIG_DSDT))
    455             {
    456                 AslGbl_ReferenceOptimizationFlag = FALSE;
    457             }
    458         }
    459     }
    460 
    461     AslGbl_FirstLevelInsertionNode = Next;
    462 }
    463 
    464 
    465 /*******************************************************************************
    466  *
    467  * FUNCTION:    TrDoSwitch
    468  *
    469  * PARAMETERS:  StartNode        - Parse node for SWITCH
    470  *
    471  * RETURN:      None
    472  *
    473  * DESCRIPTION: Translate ASL SWITCH statement to if/else pairs. There is
    474  *              no actual AML opcode for SWITCH -- it must be simulated.
    475  *
    476  ******************************************************************************/
    477 
    478 static void
    479 TrDoSwitch (
    480     ACPI_PARSE_OBJECT       *StartNode)
    481 {
    482     ACPI_PARSE_OBJECT       *Next;
    483     ACPI_PARSE_OBJECT       *CaseOp = NULL;
    484     ACPI_PARSE_OBJECT       *CaseBlock = NULL;
    485     ACPI_PARSE_OBJECT       *DefaultOp = NULL;
    486     ACPI_PARSE_OBJECT       *CurrentParentNode;
    487     ACPI_PARSE_OBJECT       *Conditional = NULL;
    488     ACPI_PARSE_OBJECT       *Predicate;
    489     ACPI_PARSE_OBJECT       *Peer;
    490     ACPI_PARSE_OBJECT       *NewOp;
    491     ACPI_PARSE_OBJECT       *NewOp2;
    492     ACPI_PARSE_OBJECT       *MethodOp;
    493     ACPI_PARSE_OBJECT       *StoreOp;
    494     ACPI_PARSE_OBJECT       *BreakOp;
    495     ACPI_PARSE_OBJECT       *BufferOp;
    496     char                    *PredicateValueName;
    497     UINT16                  Index;
    498     UINT32                  Btype;
    499 
    500 
    501     /* Start node is the Switch() node */
    502 
    503     CurrentParentNode  = StartNode;
    504 
    505     /* Create a new temp name of the form _T_x */
    506 
    507     PredicateValueName = TrAmlGetNextTempName (StartNode, &AslGbl_TempCount);
    508     if (!PredicateValueName)
    509     {
    510         return;
    511     }
    512 
    513     /* First child is the Switch() predicate */
    514 
    515     Next = StartNode->Asl.Child;
    516 
    517     /*
    518      * Examine the return type of the Switch Value -
    519      * must be Integer/Buffer/String
    520      */
    521     Index = (UINT16) (Next->Asl.ParseOpcode - ASL_PARSE_OPCODE_BASE);
    522     Btype = AslKeywordMapping[Index].AcpiBtype;
    523     if ((Btype != ACPI_BTYPE_INTEGER) &&
    524         (Btype != ACPI_BTYPE_STRING)  &&
    525         (Btype != ACPI_BTYPE_BUFFER))
    526     {
    527         AslError (ASL_WARNING, ASL_MSG_SWITCH_TYPE, Next, NULL);
    528         Btype = ACPI_BTYPE_INTEGER;
    529     }
    530 
    531     /* CASE statements start at next child */
    532 
    533     Peer = Next->Asl.Next;
    534     while (Peer)
    535     {
    536         Next = Peer;
    537         Peer = Next->Asl.Next;
    538 
    539         if (Next->Asl.ParseOpcode == PARSEOP_CASE)
    540         {
    541             if (CaseOp)
    542             {
    543                 /* Add an ELSE to complete the previous CASE */
    544 
    545                 NewOp = TrCreateLeafOp (PARSEOP_ELSE);
    546                 NewOp->Asl.Parent = Conditional->Asl.Parent;
    547                 TrAmlInitLineNumbers (NewOp, NewOp->Asl.Parent);
    548 
    549                 /* Link ELSE node as a peer to the previous IF */
    550 
    551                 TrAmlInsertPeer (Conditional, NewOp);
    552                 CurrentParentNode = NewOp;
    553             }
    554 
    555             CaseOp = Next;
    556             Conditional = CaseOp;
    557             CaseBlock = CaseOp->Asl.Child->Asl.Next;
    558             Conditional->Asl.Child->Asl.Next = NULL;
    559             Predicate = CaseOp->Asl.Child;
    560 
    561             if ((Predicate->Asl.ParseOpcode == PARSEOP_PACKAGE) ||
    562                 (Predicate->Asl.ParseOpcode == PARSEOP_VAR_PACKAGE))
    563             {
    564                 /*
    565                  * Convert the package declaration to this form:
    566                  *
    567                  * If (LNotEqual (Match (Package(<size>){<data>},
    568                  *                       MEQ, _T_x, MTR, Zero, Zero), Ones))
    569                  */
    570                 NewOp2              = TrCreateLeafOp (PARSEOP_MATCHTYPE_MEQ);
    571                 Predicate->Asl.Next = NewOp2;
    572                 TrAmlInitLineNumbers (NewOp2, Conditional);
    573 
    574                 NewOp               = NewOp2;
    575                 NewOp2              = TrCreateValuedLeafOp (PARSEOP_NAMESTRING,
    576                                         (UINT64) ACPI_TO_INTEGER (PredicateValueName));
    577                 NewOp->Asl.Next     = NewOp2;
    578                 TrAmlInitLineNumbers (NewOp2, Predicate);
    579 
    580                 NewOp               = NewOp2;
    581                 NewOp2              = TrCreateLeafOp (PARSEOP_MATCHTYPE_MTR);
    582                 NewOp->Asl.Next     = NewOp2;
    583                 TrAmlInitLineNumbers (NewOp2, Predicate);
    584 
    585                 NewOp               = NewOp2;
    586                 NewOp2              = TrCreateLeafOp (PARSEOP_ZERO);
    587                 NewOp->Asl.Next     = NewOp2;
    588                 TrAmlInitLineNumbers (NewOp2, Predicate);
    589 
    590                 NewOp               = NewOp2;
    591                 NewOp2              = TrCreateLeafOp (PARSEOP_ZERO);
    592                 NewOp->Asl.Next     = NewOp2;
    593                 TrAmlInitLineNumbers (NewOp2, Predicate);
    594 
    595                 NewOp2              = TrCreateLeafOp (PARSEOP_MATCH);
    596                 NewOp2->Asl.Child   = Predicate;  /* PARSEOP_PACKAGE */
    597                 TrAmlInitLineNumbers (NewOp2, Conditional);
    598                 TrAmlSetSubtreeParent (Predicate, NewOp2);
    599 
    600                 NewOp               = NewOp2;
    601                 NewOp2              = TrCreateLeafOp (PARSEOP_ONES);
    602                 NewOp->Asl.Next     = NewOp2;
    603                 TrAmlInitLineNumbers (NewOp2, Conditional);
    604 
    605                 NewOp2              = TrCreateLeafOp (PARSEOP_LEQUAL);
    606                 NewOp2->Asl.Child   = NewOp;
    607                 NewOp->Asl.Parent   = NewOp2;
    608                 TrAmlInitLineNumbers (NewOp2, Conditional);
    609                 TrAmlSetSubtreeParent (NewOp, NewOp2);
    610 
    611                 NewOp               = NewOp2;
    612                 NewOp2              = TrCreateLeafOp (PARSEOP_LNOT);
    613                 NewOp2->Asl.Child   = NewOp;
    614                 NewOp2->Asl.Parent  = Conditional;
    615                 NewOp->Asl.Parent   = NewOp2;
    616                 TrAmlInitLineNumbers (NewOp2, Conditional);
    617 
    618                 Conditional->Asl.Child = NewOp2;
    619                 NewOp2->Asl.Next = CaseBlock;
    620             }
    621             else
    622             {
    623                 /*
    624                  * Integer and Buffer case.
    625                  *
    626                  * Change CaseOp() to:  If (LEqual (SwitchValue, CaseValue)) {...}
    627                  * Note: SwitchValue is first to allow the CaseValue to be implicitly
    628                  * converted to the type of SwitchValue if necessary.
    629                  *
    630                  * CaseOp->Child is the case value
    631                  * CaseOp->Child->Peer is the beginning of the case block
    632                  */
    633                 NewOp = TrCreateValuedLeafOp (PARSEOP_NAMESTRING,
    634                     (UINT64) ACPI_TO_INTEGER (PredicateValueName));
    635                 NewOp->Asl.Next = Predicate;
    636                 TrAmlInitLineNumbers (NewOp, Predicate);
    637 
    638                 NewOp2              = TrCreateLeafOp (PARSEOP_LEQUAL);
    639                 NewOp2->Asl.Parent  = Conditional;
    640                 NewOp2->Asl.Child   = NewOp;
    641                 TrAmlInitLineNumbers (NewOp2, Conditional);
    642 
    643                 TrAmlSetSubtreeParent (NewOp, NewOp2);
    644 
    645                 Predicate           = NewOp2;
    646                 Predicate->Asl.Next = CaseBlock;
    647 
    648                 TrAmlSetSubtreeParent (Predicate, Conditional);
    649                 Conditional->Asl.Child = Predicate;
    650             }
    651 
    652             /* Reinitialize the CASE node to an IF node */
    653 
    654             TrAmlInitNode (Conditional, PARSEOP_IF);
    655 
    656             /*
    657              * The first CASE(IF) is not nested under an ELSE.
    658              * All other CASEs are children of a parent ELSE.
    659              */
    660             if (CurrentParentNode == StartNode)
    661             {
    662                 Conditional->Asl.Next = NULL;
    663             }
    664             else
    665             {
    666                 /*
    667                  * The IF is a child of previous IF/ELSE. It
    668                  * is therefore without peer.
    669                  */
    670                 CurrentParentNode->Asl.Child = Conditional;
    671                 Conditional->Asl.Parent      = CurrentParentNode;
    672                 Conditional->Asl.Next        = NULL;
    673             }
    674         }
    675         else if (Next->Asl.ParseOpcode == PARSEOP_DEFAULT)
    676         {
    677             if (DefaultOp)
    678             {
    679                 /*
    680                  * More than one Default
    681                  * (Parser does not catch this, must check here)
    682                  */
    683                 AslError (ASL_ERROR, ASL_MSG_MULTIPLE_DEFAULT, Next, NULL);
    684             }
    685             else
    686             {
    687                 /* Save the DEFAULT node for later, after CASEs */
    688 
    689                 DefaultOp = Next;
    690             }
    691         }
    692         else
    693         {
    694             /* Unknown peer opcode */
    695 
    696             AcpiOsPrintf ("Unknown parse opcode for switch statement: %s (%u)\n",
    697                 Next->Asl.ParseOpName, Next->Asl.ParseOpcode);
    698         }
    699     }
    700 
    701     /* Add the default case at the end of the if/else construct */
    702 
    703     if (DefaultOp)
    704     {
    705         /* If no CASE statements, this is an error - see below */
    706 
    707         if (CaseOp)
    708         {
    709             /* Convert the DEFAULT node to an ELSE */
    710 
    711             TrAmlInitNode (DefaultOp, PARSEOP_ELSE);
    712             DefaultOp->Asl.Parent = Conditional->Asl.Parent;
    713 
    714             /* Link ELSE node as a peer to the previous IF */
    715 
    716             TrAmlInsertPeer (Conditional, DefaultOp);
    717         }
    718     }
    719 
    720     if (!CaseOp)
    721     {
    722         AslError (ASL_ERROR, ASL_MSG_NO_CASES, StartNode, NULL);
    723     }
    724 
    725 
    726     /*
    727      * Create a Name(_T_x, ...) statement. This statement must appear at the
    728      * method level, in case a loop surrounds the switch statement and could
    729      * cause the name to be created twice (error).
    730      */
    731 
    732     /* Create the Name node */
    733 
    734     Predicate = StartNode->Asl.Child;
    735     NewOp = TrCreateLeafOp (PARSEOP_NAME);
    736     TrAmlInitLineNumbers (NewOp, StartNode);
    737 
    738     /* Find the parent method */
    739 
    740     Next = StartNode;
    741     while ((Next->Asl.ParseOpcode != PARSEOP_METHOD) &&
    742            (Next->Asl.ParseOpcode != PARSEOP_DEFINITION_BLOCK))
    743     {
    744         Next = Next->Asl.Parent;
    745     }
    746     MethodOp = Next;
    747 
    748     NewOp->Asl.CompileFlags |= OP_COMPILER_EMITTED;
    749     NewOp->Asl.Parent = Next;
    750 
    751     /* Insert name after the method name and arguments */
    752 
    753     Next = Next->Asl.Child; /* Name */
    754     Next = Next->Asl.Next;  /* NumArgs */
    755     Next = Next->Asl.Next;  /* SerializeRule */
    756 
    757     /*
    758      * If method is not Serialized, we must make is so, because of the way
    759      * that Switch() must be implemented -- we cannot allow multiple threads
    760      * to execute this method concurrently since we need to create local
    761      * temporary name(s).
    762      */
    763     if (Next->Asl.ParseOpcode != PARSEOP_SERIALIZERULE_SERIAL)
    764     {
    765         AslError (ASL_REMARK, ASL_MSG_SERIALIZED, MethodOp,
    766             "Due to use of Switch operator");
    767         Next->Asl.ParseOpcode = PARSEOP_SERIALIZERULE_SERIAL;
    768     }
    769 
    770     Next = Next->Asl.Next;  /* SyncLevel */
    771     Next = Next->Asl.Next;  /* ReturnType */
    772     Next = Next->Asl.Next;  /* ParameterTypes */
    773 
    774     TrAmlInsertPeer (Next, NewOp);
    775     TrAmlInitLineNumbers (NewOp, Next);
    776 
    777     /* Create the NameSeg child for the Name node */
    778 
    779     NewOp2 = TrCreateValuedLeafOp (PARSEOP_NAMESEG,
    780         (UINT64) ACPI_TO_INTEGER (PredicateValueName));
    781     TrAmlInitLineNumbers (NewOp2, NewOp);
    782     NewOp2->Asl.CompileFlags |= OP_IS_NAME_DECLARATION;
    783     NewOp->Asl.Child  = NewOp2;
    784 
    785     /* Create the initial value for the Name. Btype was already validated above */
    786 
    787     switch (Btype)
    788     {
    789     case ACPI_BTYPE_INTEGER:
    790 
    791         NewOp2->Asl.Next = TrCreateValuedLeafOp (PARSEOP_ZERO,
    792             (UINT64) 0);
    793         TrAmlInitLineNumbers (NewOp2->Asl.Next, NewOp);
    794         break;
    795 
    796     case ACPI_BTYPE_STRING:
    797 
    798         NewOp2->Asl.Next = TrCreateValuedLeafOp (PARSEOP_STRING_LITERAL,
    799             (UINT64) ACPI_TO_INTEGER (""));
    800         TrAmlInitLineNumbers (NewOp2->Asl.Next, NewOp);
    801         break;
    802 
    803     case ACPI_BTYPE_BUFFER:
    804 
    805         (void) TrLinkPeerOp (NewOp2, TrCreateValuedLeafOp (PARSEOP_BUFFER,
    806             (UINT64) 0));
    807         Next = NewOp2->Asl.Next;
    808         TrAmlInitLineNumbers (Next, NewOp2);
    809 
    810         (void) TrLinkOpChildren (Next, 1, TrCreateValuedLeafOp (PARSEOP_ZERO,
    811             (UINT64) 1));
    812         TrAmlInitLineNumbers (Next->Asl.Child, Next);
    813 
    814         BufferOp = TrCreateValuedLeafOp (PARSEOP_DEFAULT_ARG, (UINT64) 0);
    815         TrAmlInitLineNumbers (BufferOp, Next->Asl.Child);
    816         (void) TrLinkPeerOp (Next->Asl.Child, BufferOp);
    817 
    818         TrAmlSetSubtreeParent (Next->Asl.Child, Next);
    819         break;
    820 
    821     default:
    822 
    823         break;
    824     }
    825 
    826     TrAmlSetSubtreeParent (NewOp2, NewOp);
    827 
    828     /*
    829      * Transform the Switch() into a While(One)-Break node.
    830      * And create a Store() node which will be used to save the
    831      * Switch() value. The store is of the form: Store (Value, _T_x)
    832      * where _T_x is the temp variable.
    833      */
    834     TrAmlInitNode (StartNode, PARSEOP_WHILE);
    835     NewOp = TrCreateLeafOp (PARSEOP_ONE);
    836     TrAmlInitLineNumbers (NewOp, StartNode);
    837     NewOp->Asl.Next = Predicate->Asl.Next;
    838     NewOp->Asl.Parent = StartNode;
    839     StartNode->Asl.Child = NewOp;
    840 
    841     /* Create a Store() node */
    842 
    843     StoreOp = TrCreateLeafOp (PARSEOP_STORE);
    844     TrAmlInitLineNumbers (StoreOp, NewOp);
    845     StoreOp->Asl.Parent = StartNode;
    846     TrAmlInsertPeer (NewOp, StoreOp);
    847 
    848     /* Complete the Store subtree */
    849 
    850     StoreOp->Asl.Child = Predicate;
    851     Predicate->Asl.Parent = StoreOp;
    852 
    853     NewOp = TrCreateValuedLeafOp (PARSEOP_NAMESEG,
    854         (UINT64) ACPI_TO_INTEGER (PredicateValueName));
    855     TrAmlInitLineNumbers (NewOp, StoreOp);
    856     NewOp->Asl.Parent    = StoreOp;
    857     Predicate->Asl.Next  = NewOp;
    858 
    859     /* Create a Break() node and insert it into the end of While() */
    860 
    861     Conditional = StartNode->Asl.Child;
    862     while (Conditional->Asl.Next)
    863     {
    864         Conditional = Conditional->Asl.Next;
    865     }
    866 
    867     BreakOp = TrCreateLeafOp (PARSEOP_BREAK);
    868     TrAmlInitLineNumbers (BreakOp, NewOp);
    869     BreakOp->Asl.Parent = StartNode;
    870     TrAmlInsertPeer (Conditional, BreakOp);
    871 }
    872