xref: /freebsd/sys/contrib/dev/acpica/compiler/aslexternal.c (revision 7697e6c4df7188ee3a2aa66f73c572c27479bdf2)
1 /******************************************************************************
2  *
3  * Module Name: aslexternal - ASL External opcode compiler support
4  *
5  *****************************************************************************/
6 
7 /******************************************************************************
8  *
9  * 1. Copyright Notice
10  *
11  * Some or all of this work - Copyright (c) 1999 - 2026, Intel Corp.
12  * All rights reserved.
13  *
14  * 2. License
15  *
16  * 2.1. This is your license from Intel Corp. under its intellectual property
17  * rights. You may have additional license terms from the party that provided
18  * you this software, covering your right to use that party's intellectual
19  * property rights.
20  *
21  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
22  * copy of the source code appearing in this file ("Covered Code") an
23  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
24  * base code distributed originally by Intel ("Original Intel Code") to copy,
25  * make derivatives, distribute, use and display any portion of the Covered
26  * Code in any form, with the right to sublicense such rights; and
27  *
28  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
29  * license (with the right to sublicense), under only those claims of Intel
30  * patents that are infringed by the Original Intel Code, to make, use, sell,
31  * offer to sell, and import the Covered Code and derivative works thereof
32  * solely to the minimum extent necessary to exercise the above copyright
33  * license, and in no event shall the patent license extend to any additions
34  * to or modifications of the Original Intel Code. No other license or right
35  * is granted directly or by implication, estoppel or otherwise;
36  *
37  * The above copyright and patent license is granted only if the following
38  * conditions are met:
39  *
40  * 3. Conditions
41  *
42  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
43  * Redistribution of source code of any substantial portion of the Covered
44  * Code or modification with rights to further distribute source must include
45  * the above Copyright Notice, the above License, this list of Conditions,
46  * and the following Disclaimer and Export Compliance provision. In addition,
47  * Licensee must cause all Covered Code to which Licensee contributes to
48  * contain a file documenting the changes Licensee made to create that Covered
49  * Code and the date of any change. Licensee must include in that file the
50  * documentation of any changes made by any predecessor Licensee. Licensee
51  * must include a prominent statement that the modification is derived,
52  * directly or indirectly, from Original Intel Code.
53  *
54  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
55  * Redistribution of source code of any substantial portion of the Covered
56  * Code or modification without rights to further distribute source must
57  * include the following Disclaimer and Export Compliance provision in the
58  * documentation and/or other materials provided with distribution. In
59  * addition, Licensee may not authorize further sublicense of source of any
60  * portion of the Covered Code, and must include terms to the effect that the
61  * license from Licensee to its licensee is limited to the intellectual
62  * property embodied in the software Licensee provides to its licensee, and
63  * not to intellectual property embodied in modifications its licensee may
64  * make.
65  *
66  * 3.3. Redistribution of Executable. Redistribution in executable form of any
67  * substantial portion of the Covered Code or modification must reproduce the
68  * above Copyright Notice, and the following Disclaimer and Export Compliance
69  * provision in the documentation and/or other materials provided with the
70  * distribution.
71  *
72  * 3.4. Intel retains all right, title, and interest in and to the Original
73  * Intel Code.
74  *
75  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
76  * Intel shall be used in advertising or otherwise to promote the sale, use or
77  * other dealings in products derived from or relating to the Covered Code
78  * without prior written authorization from Intel.
79  *
80  * 4. Disclaimer and Export Compliance
81  *
82  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
83  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
84  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
85  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
86  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
87  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
88  * PARTICULAR PURPOSE.
89  *
90  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
91  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
92  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
93  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
94  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
95  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
96  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
97  * LIMITED REMEDY.
98  *
99  * 4.3. Licensee shall not export, either directly or indirectly, any of this
100  * software or system incorporating such software without first obtaining any
101  * required license or other approval from the U. S. Department of Commerce or
102  * any other agency or department of the United States Government. In the
103  * event Licensee exports any such software from the United States or
104  * re-exports any such software from a foreign destination, Licensee shall
105  * ensure that the distribution and export/re-export of the software is in
106  * compliance with all laws, regulations, orders, or other restrictions of the
107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
108  * any of its subsidiaries will export/re-export any technical data, process,
109  * software, or service, directly or indirectly, to any country for which the
110  * United States government or any agency thereof requires an export license,
111  * other governmental approval, or letter of assurance, without first obtaining
112  * such license, approval or letter.
113  *
114  *****************************************************************************
115  *
116  * Alternatively, you may choose to be licensed under the terms of the
117  * following license:
118  *
119  * Redistribution and use in source and binary forms, with or without
120  * modification, are permitted provided that the following conditions
121  * are met:
122  * 1. Redistributions of source code must retain the above copyright
123  *    notice, this list of conditions, and the following disclaimer,
124  *    without modification.
125  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
126  *    substantially similar to the "NO WARRANTY" disclaimer below
127  *    ("Disclaimer") and any redistribution must be conditioned upon
128  *    including a substantially similar Disclaimer requirement for further
129  *    binary redistribution.
130  * 3. Neither the names of the above-listed copyright holders nor the names
131  *    of any contributors may be used to endorse or promote products derived
132  *    from this software without specific prior written permission.
133  *
134  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
135  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
136  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
137  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
138  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
139  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
140  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
141  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
142  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
143  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
144  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
145  *
146  * Alternatively, you may choose to be licensed under the terms of the
147  * GNU General Public License ("GPL") version 2 as published by the Free
148  * Software Foundation.
149  *
150  *****************************************************************************/
151 
152 #include <contrib/dev/acpica/compiler/aslcompiler.h>
153 #include "aslcompiler.y.h"
154 #include <contrib/dev/acpica/include/acparser.h>
155 #include <contrib/dev/acpica/include/amlcode.h>
156 #include <contrib/dev/acpica/include/acnamesp.h>
157 
158 
159 #define _COMPONENT          ACPI_COMPILER
160         ACPI_MODULE_NAME    ("aslexternal")
161 
162 
163 /* Local prototypes */
164 
165 static void
166 ExInsertArgCount (
167     ACPI_PARSE_OBJECT       *Op);
168 
169 static void
170 ExMoveExternals (
171     ACPI_PARSE_OBJECT       *DefinitionBlockOp);
172 
173 static void
174 ExRemoveOpFromTree (
175     ACPI_PARSE_OBJECT       *Op);
176 
177 
178 /*******************************************************************************
179  *
180  * FUNCTION:    ExDoExternal
181  *
182  * PARAMETERS:  Op                  - Current Parse node
183  *
184  * RETURN:      None
185  *
186  * DESCRIPTION: Add an External() definition to the global list. This list
187  *              is used to generate External opcodes.
188  *
189  ******************************************************************************/
190 
191 void
ExDoExternal(ACPI_PARSE_OBJECT * Op)192 ExDoExternal (
193     ACPI_PARSE_OBJECT       *Op)
194 {
195     ACPI_PARSE_OBJECT       *ListOp;
196     ACPI_PARSE_OBJECT       *Prev;
197     ACPI_PARSE_OBJECT       *Next;
198     ACPI_PARSE_OBJECT       *ArgCountOp;
199     ACPI_PARSE_OBJECT       *TypeOp;
200     ACPI_PARSE_OBJECT       *ExternTypeOp = Op->Asl.Child->Asl.Next;
201     ACPI_PARSE_OBJECT       *Existing;
202     ACPI_PARSE_OBJECT       *NameOp = Op->Asl.Child;
203     ACPI_PARSE_OBJECT       *ExistingNameOp;
204     UINT32                  ExternType;
205     UINT8                   ParamCount = ASL_EXTERNAL_METHOD_UNKNOWN_PARAMS;
206     UINT32                  ParamTypes[ACPI_METHOD_NUM_ARGS];
207     char                    *NewPath = NULL;
208     char                    *ExistingPath;
209 
210 
211     ExternType = AnMapObjTypeToBtype (ExternTypeOp);
212     if (ExternType != ACPI_BTYPE_METHOD)
213     {
214         /*
215          * If this is not a method, it has zero parameters this local variable
216          * is used only for methods
217          */
218         ParamCount = 0;
219     }
220 
221     /*
222      * The parser allows optional parameter return types regardless of the
223      * type. Check object type keyword emit error if optional parameter/return
224      * types exist.
225      *
226      * Check the parameter return type
227      */
228     TypeOp = ExternTypeOp->Asl.Next;
229     if (TypeOp->Asl.Child)
230     {
231         /* Ignore the return type for now. */
232 
233         (void) MtProcessTypeOp (TypeOp->Asl.Child);
234         if (ExternType != ACPI_BTYPE_METHOD)
235         {
236             sprintf (AslGbl_MsgBuffer, "Found type [%s]", AcpiUtGetTypeName(ExternType));
237             AslError (ASL_ERROR, ASL_MSG_EXTERN_INVALID_RET_TYPE, TypeOp,
238                 AslGbl_MsgBuffer);
239         }
240     }
241 
242     /* Check the parameter types */
243 
244     TypeOp = TypeOp->Asl.Next;
245     if (TypeOp->Asl.Child)
246     {
247         ParamCount = MtProcessParameterTypeList (TypeOp->Asl.Child, ParamTypes);
248         if (ExternType != ACPI_BTYPE_METHOD)
249         {
250             sprintf (AslGbl_MsgBuffer, "Found type [%s]", AcpiUtGetTypeName(ExternType));
251             AslError (ASL_ERROR, ASL_MSG_EXTERN_INVALID_PARAM_TYPE, TypeOp,
252                 AslGbl_MsgBuffer);
253         }
254     }
255 
256     ArgCountOp = Op->Asl.Child->Asl.Next->Asl.Next;
257     ArgCountOp->Asl.AmlOpcode = AML_RAW_DATA_BYTE;
258     ArgCountOp->Asl.ParseOpcode = PARSEOP_BYTECONST;
259     ArgCountOp->Asl.Value.Integer = ParamCount;
260     UtSetParseOpName (ArgCountOp);
261 
262     /*
263      * Deduplicate identical External() declarations. The disassembler
264      * already collapses duplicates; mirror that behavior in the compiler
265      * so duplicate externals do not bloat emitted AML.
266      */
267 
268     NewPath = NameOp->Asl.Namepath;
269     if (!NewPath && NameOp->Asl.Value.String)
270     {
271         (void) UtInternalizeName (NameOp->Asl.Value.String, &NewPath);
272         NameOp->Asl.Namepath = NewPath;
273     }
274 
275     Existing = AslGbl_ExternalsListHead;
276     while (Existing && NewPath)
277     {
278         ExistingNameOp = Existing->Asl.Child->Asl.Child;
279         ExistingPath = ExistingNameOp->Asl.Namepath;
280         if (!ExistingPath && ExistingNameOp->Asl.Value.String)
281         {
282             (void) UtInternalizeName (ExistingNameOp->Asl.Value.String,
283                 &ExistingPath);
284             ExistingNameOp->Asl.Namepath = ExistingPath;
285         }
286 
287         if (ExistingPath && !strcmp (NewPath, ExistingPath))
288         {
289             ACPI_PARSE_OBJECT *ExistingArgCount;
290 
291             /* Update arg count if this instance is more specific */
292 
293             ExistingArgCount = Existing->Asl.Child->Asl.Child->Asl.Next->Asl.Next;
294             if ((ExternType == ACPI_BTYPE_METHOD) &&
295                 (ParamCount < ExistingArgCount->Asl.Value.Integer))
296             {
297                 ExistingArgCount->Asl.Value.Integer = ParamCount;
298             }
299 
300             /* Remove duplicate External node from the parse tree */
301 
302             ExRemoveOpFromTree (Op);
303             return;
304         }
305 
306         Existing = Existing->Asl.Next;
307     }
308 
309     /* Create new list node of arbitrary type */
310 
311     ListOp = TrAllocateOp (PARSEOP_DEFAULT_ARG);
312 
313     /* Store External node as child */
314 
315     ListOp->Asl.Child = Op;
316     ListOp->Asl.Next = NULL;
317 
318     if (AslGbl_ExternalsListHead)
319     {
320         /* Link new External to end of list */
321 
322         Prev = AslGbl_ExternalsListHead;
323         Next = Prev;
324         while (Next)
325         {
326             Prev = Next;
327             Next = Next->Asl.Next;
328         }
329 
330         Prev->Asl.Next = ListOp;
331     }
332     else
333     {
334         AslGbl_ExternalsListHead = ListOp;
335     }
336 }
337 
338 
339 /*******************************************************************************
340  *
341  * FUNCTION:    ExRemoveOpFromTree
342  *
343  * PARAMETERS:  Op              - Parse op to remove from the tree
344  *
345  * RETURN:      None
346  *
347  * DESCRIPTION: Unlink a parse op from its parent sibling list. Used to drop
348  *              duplicate External() declarations before AML emission.
349  *
350  ******************************************************************************/
351 
352 static void
ExRemoveOpFromTree(ACPI_PARSE_OBJECT * Op)353 ExRemoveOpFromTree (
354     ACPI_PARSE_OBJECT       *Op)
355 {
356     ACPI_PARSE_OBJECT       *Parent;
357     ACPI_PARSE_OBJECT       *Child;
358 
359 
360     if (!Op || !Op->Asl.Parent)
361     {
362         return;
363     }
364 
365     Parent = Op->Asl.Parent;
366     Child = Parent->Asl.Child;
367 
368     if (Child == Op)
369     {
370         Parent->Asl.Child = Op->Asl.Next;
371         return;
372     }
373 
374     while (Child && Child->Asl.Next != Op)
375     {
376         Child = Child->Asl.Next;
377     }
378 
379     if (Child)
380     {
381         Child->Asl.Next = Op->Asl.Next;
382     }
383 }
384 
385 
386 /*******************************************************************************
387  *
388  * FUNCTION:    ExInsertArgCount
389  *
390  * PARAMETERS:  Op              - Op for a method invocation
391  *
392  * RETURN:      None
393  *
394  * DESCRIPTION: Obtain the number of arguments for a control method -- from
395  *              the actual invocation.
396  *
397  ******************************************************************************/
398 
399 static void
ExInsertArgCount(ACPI_PARSE_OBJECT * Op)400 ExInsertArgCount (
401     ACPI_PARSE_OBJECT       *Op)
402 {
403     ACPI_PARSE_OBJECT       *Next;
404     ACPI_PARSE_OBJECT       *NameOp;
405     ACPI_PARSE_OBJECT       *Child;
406     ACPI_PARSE_OBJECT       *ArgCountOp;
407     char *                  ExternalName;
408     char *                  CallName;
409     UINT16                  ArgCount = 0;
410     ACPI_STATUS             Status;
411 
412 
413     CallName = AcpiNsGetNormalizedPathname (Op->Asl.Node, TRUE);
414 
415     Next = AslGbl_ExternalsListHead;
416     while (Next)
417     {
418         ArgCount = 0;
419 
420         /* Skip if External node already handled */
421 
422         if (Next->Asl.Child->Asl.CompileFlags & OP_VISITED)
423         {
424             Next = Next->Asl.Next;
425             continue;
426         }
427 
428         NameOp = Next->Asl.Child->Asl.Child;
429         ExternalName = AcpiNsGetNormalizedPathname (NameOp->Asl.Node, TRUE);
430 
431         if (strcmp (CallName, ExternalName))
432         {
433             ACPI_FREE (ExternalName);
434             Next = Next->Asl.Next;
435             continue;
436         }
437 
438         Next->Asl.Child->Asl.CompileFlags |= OP_VISITED;
439 
440         /*
441          * Since we will reposition Externals to the Root, set Namepath
442          * to the fully qualified name and recalculate the aml length
443          */
444         Status = UtInternalizeName (ExternalName,
445             &NameOp->Asl.Value.String);
446 
447         ACPI_FREE (ExternalName);
448         if (ACPI_FAILURE (Status))
449         {
450             AslError (ASL_ERROR, ASL_MSG_COMPILER_INTERNAL,
451                 NULL, "- Could not Internalize External");
452             break;
453         }
454 
455         NameOp->Asl.AmlLength = strlen (NameOp->Asl.Value.String);
456 
457         /* Get argument count */
458 
459         Child = Op->Asl.Child;
460         while (Child)
461         {
462             ArgCount++;
463             Child = Child->Asl.Next;
464         }
465 
466         /* Setup ArgCount operand */
467 
468         ArgCountOp = Next->Asl.Child->Asl.Child->Asl.Next->Asl.Next;
469         ArgCountOp->Asl.Value.Integer = ArgCount;
470         break;
471     }
472 
473     ACPI_FREE (CallName);
474 }
475 
476 
477 /*******************************************************************************
478  *
479  * FUNCTION:    ExAmlExternalWalkBegin
480  *
481  * PARAMETERS:  ASL_WALK_CALLBACK
482  *
483  * RETURN:      None
484  *
485  * DESCRIPTION: Parse tree walk to create external opcode list for methods.
486  *
487  ******************************************************************************/
488 
489 ACPI_STATUS
ExAmlExternalWalkBegin(ACPI_PARSE_OBJECT * Op,UINT32 Level,void * Context)490 ExAmlExternalWalkBegin (
491     ACPI_PARSE_OBJECT       *Op,
492     UINT32                  Level,
493     void                    *Context)
494 {
495 
496     /* External list head saved in the definition block op */
497 
498     if (Op->Asl.ParseOpcode == PARSEOP_DEFINITION_BLOCK)
499     {
500         AslGbl_ExternalsListHead = Op->Asl.Value.Arg;
501     }
502 
503     if (!AslGbl_ExternalsListHead)
504     {
505         return (AE_OK);
506     }
507 
508     if (Op->Asl.ParseOpcode != PARSEOP_METHODCALL)
509     {
510         return (AE_OK);
511     }
512 
513     /*
514      * The NameOp child under an ExternalOp gets turned into PARSE_METHODCALL
515      * by XfNamespaceLocateBegin(). Ignore these.
516      */
517     if (Op->Asl.Parent &&
518         Op->Asl.Parent->Asl.ParseOpcode == PARSEOP_EXTERNAL)
519     {
520         return (AE_OK);
521     }
522 
523     ExInsertArgCount (Op);
524     return (AE_OK);
525 }
526 
527 
528 /*******************************************************************************
529  *
530  * FUNCTION:    ExAmlExternalWalkEnd
531  *
532  * PARAMETERS:  ASL_WALK_CALLBACK
533  *
534  * RETURN:      None
535  *
536  * DESCRIPTION: Parse tree walk to create external opcode list for methods.
537  *              Here, we just want to catch the case where a definition block
538  *              has been completed. Then we move all of the externals into
539  *              a single block in the parse tree and thus the AML code.
540  *
541  ******************************************************************************/
542 
543 ACPI_STATUS
ExAmlExternalWalkEnd(ACPI_PARSE_OBJECT * Op,UINT32 Level,void * Context)544 ExAmlExternalWalkEnd (
545     ACPI_PARSE_OBJECT       *Op,
546     UINT32                  Level,
547     void                    *Context)
548 {
549 
550     if (Op->Asl.ParseOpcode == PARSEOP_DEFINITION_BLOCK)
551     {
552         /*
553          * Process any existing external list. (Support for
554          * multiple definition blocks in a single file/compile)
555          */
556         ExMoveExternals (Op);
557         AslGbl_ExternalsListHead = NULL;
558     }
559 
560     return (AE_OK);
561 }
562 
563 
564 /*******************************************************************************
565  *
566  * FUNCTION:    ExMoveExternals
567  *
568  * PARAMETERS:  DefinitionBlockOp       - Op for current definition block
569  *
570  * RETURN:      None
571  *
572  * DESCRIPTION: Move all externals present in the source file into a single
573  *              block of AML code, surrounded by an "If (0)" to prevent
574  *              AML interpreters from attempting to execute the External
575  *              opcodes.
576  *
577  ******************************************************************************/
578 
579 static void
ExMoveExternals(ACPI_PARSE_OBJECT * DefinitionBlockOp)580 ExMoveExternals (
581     ACPI_PARSE_OBJECT       *DefinitionBlockOp)
582 {
583     ACPI_PARSE_OBJECT       *ParentOp;
584     ACPI_PARSE_OBJECT       *ExternalOp;
585     ACPI_PARSE_OBJECT       *PredicateOp;
586     ACPI_PARSE_OBJECT       *NextOp;
587     ACPI_PARSE_OBJECT       *Prev;
588     ACPI_PARSE_OBJECT       *Next;
589     char                    *ExternalName;
590     ACPI_OBJECT_TYPE        ObjType;
591     ACPI_STATUS             Status;
592     UINT32                  i;
593 
594 
595     if (!AslGbl_ExternalsListHead)
596     {
597         return;
598     }
599 
600     /* Remove the External nodes from the tree */
601 
602     NextOp = AslGbl_ExternalsListHead;
603     while (NextOp)
604     {
605         /*
606          * The External is stored in child pointer of each node in the
607          * list
608          */
609         ExternalOp = NextOp->Asl.Child;
610 
611         /* Get/set the fully qualified name */
612 
613         ExternalName = AcpiNsGetNormalizedPathname (ExternalOp->Asl.Node, TRUE);
614         ExternalOp->Asl.ExternalName = ExternalName;
615         ExternalOp->Asl.Namepath = ExternalName;
616 
617         /* Set line numbers (for listings, etc.) */
618 
619         ExternalOp->Asl.LineNumber = 0;
620         ExternalOp->Asl.LogicalLineNumber = 0;
621 
622         Next = ExternalOp->Asl.Child;
623         Next->Asl.LineNumber = 0;
624         Next->Asl.LogicalLineNumber = 0;
625 
626         if (Next->Asl.ParseOpcode == PARSEOP_NAMESEG)
627         {
628             Next->Asl.ParseOpcode = PARSEOP_NAMESTRING;
629         }
630 
631         Next->Asl.ExternalName = ExternalName;
632         Status = UtInternalizeName (ExternalName, &Next->Asl.Value.String);
633         if (ACPI_FAILURE (Status))
634         {
635             AslError (ASL_ERROR, ASL_MSG_COMPILER_INTERNAL,
636                 Next, "Could not internalize namestring");
637             return;
638         }
639 
640         Next->Asl.AmlLength = strlen (Next->Asl.Value.String);
641 
642         Next = Next->Asl.Next;
643         Next->Asl.LineNumber = 0;
644         Next->Asl.LogicalLineNumber = 0;
645 
646         Next = Next->Asl.Next;
647         Next->Asl.LineNumber = 0;
648         Next->Asl.LogicalLineNumber = 0;
649 
650         Next = Next->Asl.Next;
651         Next->Asl.LineNumber = 0;
652         Next->Asl.LogicalLineNumber = 0;
653 
654         ParentOp = ExternalOp->Asl.Parent;
655         Prev = Next = ParentOp->Asl.Child;
656 
657         /* Now find the External node's position in parse tree */
658 
659         while (Next != ExternalOp)
660         {
661             Prev = Next;
662             Next = Next->Asl.Next;
663         }
664 
665         /* Remove the External from the parse tree */
666 
667         if (Prev == ExternalOp)
668         {
669             /* External was the first child node */
670 
671             ParentOp->Asl.Child = ExternalOp->Asl.Next;
672         }
673 
674         Prev->Asl.Next = ExternalOp->Asl.Next;
675         ExternalOp->Asl.Next = NULL;
676         ExternalOp->Asl.Parent = AslGbl_ExternalsListHead;
677 
678         /* Point the External to the next in the list */
679 
680         if (NextOp->Asl.Next)
681         {
682             ExternalOp->Asl.Next = NextOp->Asl.Next->Asl.Child;
683         }
684 
685         NextOp = NextOp->Asl.Next;
686     }
687 
688     /*
689      * Loop again to remove MethodObj Externals for which
690      * a MethodCall was not found (dead external reference)
691      */
692     Prev = AslGbl_ExternalsListHead->Asl.Child;
693     Next = Prev;
694     while (Next)
695     {
696         ObjType = (ACPI_OBJECT_TYPE)
697             Next->Asl.Child->Asl.Next->Asl.Value.Integer;
698 
699         if (ObjType == ACPI_TYPE_METHOD &&
700             !(Next->Asl.CompileFlags & OP_VISITED))
701         {
702             if (Next == Prev)
703             {
704                 AslGbl_ExternalsListHead->Asl.Child = Next->Asl.Next;
705                 Next->Asl.Next = NULL;
706                 Prev = AslGbl_ExternalsListHead->Asl.Child;
707                 Next = Prev;
708                 continue;
709             }
710             else
711             {
712                 Prev->Asl.Next = Next->Asl.Next;
713                 Next->Asl.Next = NULL;
714                 Next = Prev->Asl.Next;
715                 continue;
716             }
717         }
718 
719         Prev = Next;
720         Next = Next->Asl.Next;
721     }
722 
723     /* If list is now empty, don't bother to make If (0) block */
724 
725     if (!AslGbl_ExternalsListHead->Asl.Child)
726     {
727         return;
728     }
729 
730     /* Convert Gbl_ExternalsListHead parent to If(). */
731 
732     AslGbl_ExternalsListHead->Asl.ParseOpcode = PARSEOP_IF;
733     AslGbl_ExternalsListHead->Asl.AmlOpcode = AML_IF_OP;
734     AslGbl_ExternalsListHead->Asl.CompileFlags = OP_AML_PACKAGE;
735     UtSetParseOpName (AslGbl_ExternalsListHead);
736 
737     /* Create a Zero op for the If predicate */
738 
739     PredicateOp = TrAllocateOp (PARSEOP_ZERO);
740     PredicateOp->Asl.AmlOpcode = AML_ZERO_OP;
741 
742     PredicateOp->Asl.Parent = AslGbl_ExternalsListHead;
743     PredicateOp->Asl.Child = NULL;
744     PredicateOp->Asl.Next = AslGbl_ExternalsListHead->Asl.Child;
745     AslGbl_ExternalsListHead->Asl.Child = PredicateOp;
746 
747     /* Set line numbers (for listings, etc.) */
748 
749     AslGbl_ExternalsListHead->Asl.LineNumber = 0;
750     AslGbl_ExternalsListHead->Asl.LogicalLineNumber = 0;
751 
752     PredicateOp->Asl.LineNumber = 0;
753     PredicateOp->Asl.LogicalLineNumber = 0;
754 
755     /* Insert block back in the list */
756 
757     Prev = DefinitionBlockOp->Asl.Child;
758     Next = Prev;
759 
760     /* Find last default arg */
761 
762     for (i = 0; i < 6; i++)
763     {
764         Prev = Next;
765         Next = Prev->Asl.Next;
766     }
767 
768     if (Next)
769     {
770         /* Definition Block is not empty */
771 
772         AslGbl_ExternalsListHead->Asl.Next = Next;
773     }
774     else
775     {
776         /* Definition Block is empty. */
777 
778         AslGbl_ExternalsListHead->Asl.Next = NULL;
779     }
780 
781     Prev->Asl.Next = AslGbl_ExternalsListHead;
782     AslGbl_ExternalsListHead->Asl.Parent = Prev->Asl.Parent;
783 }
784