1 /******************************************************************************
3 * Module Name: aslmethod.c - Control method analysis walk
5 *****************************************************************************/
7 /******************************************************************************
11 * Some or all of this work - Copyright (c) 1999 - 2020, Intel Corp.
12 * All rights reserved.
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
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
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;
37 * The above copyright and patent license is granted only if the following
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.
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
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
72 * 3.4. Intel retains all right, title, and interest in and to the Original
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.
80 * 4. Disclaimer and Export Compliance
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
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
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.
114 *****************************************************************************
116 * Alternatively, you may choose to be licensed under the terms of the
119 * Redistribution and use in source and binary forms, with or without
120 * modification, are permitted provided that the following conditions
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.
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.
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.
150 *****************************************************************************/
152 #include "aslcompiler.h"
153 #include "aslcompiler.y.h"
154 #include "acparser.h"
158 #define _COMPONENT ACPI_COMPILER
159 ACPI_MODULE_NAME ("aslmethod")
162 /* Local prototypes */
165 MtCheckNamedObjectInMethod (
166 ACPI_PARSE_OBJECT *Op,
167 ASL_METHOD_INFO *MethodInfo);
170 /*******************************************************************************
172 * FUNCTION: MtMethodAnalysisWalkBegin
174 * PARAMETERS: ASL_WALK_CALLBACK
178 * DESCRIPTION: Descending callback for the analysis walk. Check methods for:
179 * 1) Initialized local variables
183 ******************************************************************************/
186 MtMethodAnalysisWalkBegin (
187 ACPI_PARSE_OBJECT *Op,
191 ASL_ANALYSIS_WALK_INFO *WalkInfo = (ASL_ANALYSIS_WALK_INFO *) Context;
192 ASL_METHOD_INFO *MethodInfo = WalkInfo->MethodStack;
193 ACPI_PARSE_OBJECT *Next;
194 UINT32 RegisterNumber;
196 char LocalName[] = "Local0";
197 char ArgName[] = "Arg0";
198 ACPI_PARSE_OBJECT *ArgNode;
199 ACPI_PARSE_OBJECT *NextType;
200 ACPI_PARSE_OBJECT *NextParamType;
201 UINT8 ActualArgs = 0;
206 /* Build cross-reference output file if requested */
208 if (AslGbl_CrossReferenceOutput)
210 OtXrefWalkPart1 (Op, Level, MethodInfo);
213 switch (Op->Asl.ParseOpcode)
217 AslGbl_TotalMethods++;
219 /* Create and init method info */
221 MethodInfo = UtLocalCalloc (sizeof (ASL_METHOD_INFO));
222 MethodInfo->Next = WalkInfo->MethodStack;
225 WalkInfo->MethodStack = MethodInfo;
228 * Special handling for _PSx methods. Dependency rules (same scope):
230 * 1) _PS0 - One of these must exist: _PS1, _PS2, _PS3
231 * 2) _PS1/_PS2/_PS3: A _PS0 must exist
233 if (ACPI_COMPARE_NAMESEG (METHOD_NAME__PS0, Op->Asl.NameSeg))
235 /* For _PS0, one of _PS1/_PS2/_PS3 must exist */
237 if ((!ApFindNameInScope (METHOD_NAME__PS1, Op)) &&
238 (!ApFindNameInScope (METHOD_NAME__PS2, Op)) &&
239 (!ApFindNameInScope (METHOD_NAME__PS3, Op)))
241 AslError (ASL_WARNING, ASL_MSG_MISSING_DEPENDENCY, Op,
242 "_PS0 requires one of _PS1/_PS2/_PS3 in same scope");
246 ACPI_COMPARE_NAMESEG (METHOD_NAME__PS1, Op->Asl.NameSeg) ||
247 ACPI_COMPARE_NAMESEG (METHOD_NAME__PS2, Op->Asl.NameSeg) ||
248 ACPI_COMPARE_NAMESEG (METHOD_NAME__PS3, Op->Asl.NameSeg))
250 /* For _PS1/_PS2/_PS3, a _PS0 must exist */
252 if (!ApFindNameInScope (METHOD_NAME__PS0, Op))
254 sprintf (AslGbl_MsgBuffer,
255 "%4.4s requires _PS0 in same scope", Op->Asl.NameSeg);
257 AslError (ASL_WARNING, ASL_MSG_MISSING_DEPENDENCY, Op,
262 /* Get the name node */
264 Next = Op->Asl.Child;
266 /* Get the NumArguments node */
268 Next = Next->Asl.Next;
269 MethodInfo->NumArguments = (UINT8)
270 (((UINT8) Next->Asl.Value.Integer) & 0x07);
272 /* Get the SerializeRule and SyncLevel nodes, ignored here */
274 Next = Next->Asl.Next;
275 MethodInfo->ShouldBeSerialized = (UINT8) Next->Asl.Value.Integer;
277 Next = Next->Asl.Next;
280 /* Get the ReturnType node */
282 Next = Next->Asl.Next;
284 NextType = Next->Asl.Child;
287 /* Get and map each of the ReturnTypes */
289 MethodInfo->ValidReturnTypes |= AnMapObjTypeToBtype (NextType);
290 NextType->Asl.ParseOpcode = PARSEOP_DEFAULT_ARG;
291 NextType = NextType->Asl.Next;
294 /* Get the ParameterType node */
296 Next = Next->Asl.Next;
298 NextType = Next->Asl.Child;
301 if (NextType->Asl.ParseOpcode == PARSEOP_DEFAULT_ARG)
303 NextParamType = NextType->Asl.Child;
304 while (NextParamType)
306 MethodInfo->ValidArgTypes[ActualArgs] |=
307 AnMapObjTypeToBtype (NextParamType);
309 NextParamType->Asl.ParseOpcode = PARSEOP_DEFAULT_ARG;
310 NextParamType = NextParamType->Asl.Next;
315 MethodInfo->ValidArgTypes[ActualArgs] =
316 AnMapObjTypeToBtype (NextType);
318 NextType->Asl.ParseOpcode = PARSEOP_DEFAULT_ARG;
322 NextType = NextType->Asl.Next;
325 if ((MethodInfo->NumArguments) &&
326 (MethodInfo->NumArguments != ActualArgs))
328 /* error: Param list did not match number of args */
331 /* Allow numarguments == 0 for Function() */
333 if ((!MethodInfo->NumArguments) && (ActualArgs))
335 MethodInfo->NumArguments = ActualArgs;
336 ArgNode->Asl.Value.Integer |= ActualArgs;
340 * Actual arguments are initialized at method entry.
341 * All other ArgX "registers" can be used as locals, so we
342 * track their initialization.
344 for (i = 0; i < MethodInfo->NumArguments; i++)
346 MethodInfo->ArgInitialized[i] = TRUE;
350 case PARSEOP_METHODCALL:
352 /* Check for a recursive method call */
355 (Op->Asl.Node == MethodInfo->Op->Asl.Node))
357 if (MethodInfo->CreatesNamedObjects)
360 * This is an error, as it will fail at runtime on all ACPI
361 * implementations. Any named object declarations will be
362 * executed twice, causing failure the second time. Note,
363 * this is independent of whether the method is declared
364 * Serialized, because the same thread is attempting to
365 * reenter the method, and this will always succeed.
367 AslDualParseOpError (ASL_ERROR, ASL_MSG_ILLEGAL_RECURSION, Op,
368 Op->Asl.Value.String, ASL_MSG_FOUND_HERE, MethodInfo->Op,
369 MethodInfo->Op->Asl.ExternalName);
373 /* Method does not create objects, issue a remark */
375 AslError (ASL_REMARK, ASL_MSG_RECURSION, Op, Op->Asl.ExternalName);
392 * Local was used outside a control method, or there was an error
393 * in the method declaration.
395 AslError (ASL_REMARK, ASL_MSG_LOCAL_OUTSIDE_METHOD,
396 Op, Op->Asl.ExternalName);
400 RegisterNumber = (Op->Asl.AmlOpcode & 0x0007);
403 * If the local is being used as a target, mark the local
406 if (Op->Asl.CompileFlags & OP_IS_TARGET)
408 MethodInfo->LocalInitialized[RegisterNumber] = TRUE;
412 * Otherwise, this is a reference, check if the local
413 * has been previously initialized.
415 * The only operator that accepts an uninitialized value is ObjectType()
417 else if ((!MethodInfo->LocalInitialized[RegisterNumber]) &&
418 (Op->Asl.Parent->Asl.ParseOpcode != PARSEOP_OBJECTTYPE))
420 LocalName[strlen (LocalName) -1] = (char) (RegisterNumber + 0x30);
421 AslError (ASL_ERROR, ASL_MSG_LOCAL_INIT, Op, LocalName);
436 * Arg was used outside a control method, or there was an error
437 * in the method declaration.
439 AslError (ASL_REMARK, ASL_MSG_LOCAL_OUTSIDE_METHOD,
440 Op, Op->Asl.ExternalName);
444 RegisterNumber = (Op->Asl.AmlOpcode & 0x000F) - 8;
445 ArgName[strlen (ArgName) -1] = (char) (RegisterNumber + 0x30);
448 * If the Arg is being used as a target, mark the local
451 if (Op->Asl.CompileFlags & OP_IS_TARGET)
453 MethodInfo->ArgInitialized[RegisterNumber] = TRUE;
457 * Otherwise, this is a reference, check if the Arg
458 * has been previously initialized.
460 * The only operator that accepts an uninitialized value is ObjectType()
462 else if ((!MethodInfo->ArgInitialized[RegisterNumber]) &&
463 (Op->Asl.Parent->Asl.ParseOpcode != PARSEOP_OBJECTTYPE))
465 AslError (ASL_ERROR, ASL_MSG_ARG_INIT, Op, ArgName);
468 /* Flag this arg if it is not a "real" argument to the method */
470 if (RegisterNumber >= MethodInfo->NumArguments)
472 AslError (ASL_REMARK, ASL_MSG_NOT_PARAMETER, Op, ArgName);
481 * Probably was an error in the method declaration,
482 * no additional error here
484 ACPI_WARNING ((AE_INFO, "%p, No parent method", Op));
489 * A child indicates a possible return value. A simple Return or
490 * Return() is marked with OP_IS_NULL_RETURN by the parser so
491 * that it is not counted as a "real" return-with-value, although
492 * the AML code that is actually emitted is Return(0). The AML
493 * definition of Return has a required parameter, so we are
494 * forced to convert a null return to Return(0).
496 if ((Op->Asl.Child) &&
497 (Op->Asl.Child->Asl.ParseOpcode != PARSEOP_DEFAULT_ARG) &&
498 (!(Op->Asl.Child->Asl.CompileFlags & OP_IS_NULL_RETURN)))
500 MethodInfo->NumReturnWithValue++;
504 MethodInfo->NumReturnNoValue++;
509 case PARSEOP_CONTINUE:
511 Next = Op->Asl.Parent;
514 if (Next->Asl.ParseOpcode == PARSEOP_WHILE)
518 Next = Next->Asl.Parent;
523 AslError (ASL_ERROR, ASL_MSG_NO_WHILE, Op, NULL);
529 /* We can range check if the argument is an integer */
531 if ((Op->Asl.Child->Asl.ParseOpcode == PARSEOP_INTEGER) &&
532 (Op->Asl.Child->Asl.Value.Integer > ACPI_UINT8_MAX))
534 AslError (ASL_ERROR, ASL_MSG_INVALID_TIME, Op, NULL);
540 /* Check usage of _HID and _ADR objects */
542 HidExists = ApFindNameInDeviceTree (METHOD_NAME__HID, Op);
543 AdrExists = ApFindNameInDeviceTree (METHOD_NAME__ADR, Op);
545 if (!HidExists && !AdrExists)
547 AslError (ASL_WARNING, ASL_MSG_MISSING_DEPENDENCY, Op,
548 "Device object requires a _HID or _ADR in same scope");
550 else if (HidExists && AdrExists)
553 * According to the ACPI spec, "A device object must contain
554 * either an _HID object or an _ADR object, but should not contain
557 AslError (ASL_WARNING, ASL_MSG_MULTIPLE_TYPES, Op,
558 "Device object requires either a _HID or _ADR, but not both");
564 case PARSEOP_OPERATIONREGION:
565 case PARSEOP_POWERRESOURCE:
566 case PARSEOP_PROCESSOR:
567 case PARSEOP_THERMALZONE:
570 * The first operand is a name to be created in the namespace.
571 * Check against the reserved list.
573 i = ApCheckForPredefinedName (Op, Op->Asl.NameSeg);
574 if (i < ACPI_VALID_RESERVED_NAME_MAX)
576 AslError (ASL_ERROR, ASL_MSG_RESERVED_USE,
577 Op, Op->Asl.ExternalName);
583 /* Typecheck any predefined names statically defined with Name() */
585 ApCheckForPredefinedObject (Op, Op->Asl.NameSeg);
587 /* Special typechecking for _HID */
589 if (ACPI_COMPARE_NAMESEG (METHOD_NAME__HID, Op->Asl.NameSeg))
591 Next = Op->Asl.Child->Asl.Next;
592 AnCheckId (Next, ASL_TYPE_HID);
595 /* Special typechecking for _CID */
597 else if (ACPI_COMPARE_NAMESEG (METHOD_NAME__CID, Op->Asl.NameSeg))
599 Next = Op->Asl.Child->Asl.Next;
601 if ((Next->Asl.ParseOpcode == PARSEOP_PACKAGE) ||
602 (Next->Asl.ParseOpcode == PARSEOP_VAR_PACKAGE))
604 Next = Next->Asl.Child;
607 AnCheckId (Next, ASL_TYPE_CID);
608 Next = Next->Asl.Next;
613 AnCheckId (Next, ASL_TYPE_CID);
624 /* Check for named object creation within a non-serialized method */
626 MtCheckNamedObjectInMethod (Op, MethodInfo);
631 /*******************************************************************************
633 * FUNCTION: MtCheckNamedObjectInMethod
635 * PARAMETERS: Op - Current parser op
636 * MethodInfo - Info for method being parsed
640 * DESCRIPTION: Detect if a non-serialized method is creating a named object,
641 * which could possibly cause problems if two threads execute
642 * the method concurrently. Emit a remark in this case.
644 ******************************************************************************/
647 MtCheckNamedObjectInMethod (
648 ACPI_PARSE_OBJECT *Op,
649 ASL_METHOD_INFO *MethodInfo)
651 const ACPI_OPCODE_INFO *OpInfo;
654 /* We don't care about actual method declarations or scopes */
656 if ((Op->Asl.AmlOpcode == AML_METHOD_OP) ||
657 (Op->Asl.AmlOpcode == AML_SCOPE_OP))
662 /* Determine if we are creating a named object within a method */
669 OpInfo = AcpiPsGetOpcodeInfo (Op->Asl.AmlOpcode);
670 if (OpInfo->Class == AML_CLASS_NAMED_OBJECT)
673 * 1) Mark the method as a method that creates named objects.
675 * 2) If the method is non-serialized, emit a remark that the method
676 * should be serialized.
678 * Reason: If a thread blocks within the method for any reason, and
679 * another thread enters the method, the method will fail because
680 * an attempt will be made to create the same object twice.
682 MethodInfo->CreatesNamedObjects = TRUE;
683 if (!MethodInfo->ShouldBeSerialized)
685 AslError (ASL_REMARK, ASL_MSG_SERIALIZED_REQUIRED, MethodInfo->Op,
686 "due to creation of named objects within");
688 /* Emit message only ONCE per method */
690 MethodInfo->ShouldBeSerialized = TRUE;
696 /*******************************************************************************
698 * FUNCTION: MtMethodAnalysisWalkEnd
700 * PARAMETERS: ASL_WALK_CALLBACK
704 * DESCRIPTION: Ascending callback for analysis walk. Complete method
707 ******************************************************************************/
710 MtMethodAnalysisWalkEnd (
711 ACPI_PARSE_OBJECT *Op,
715 ASL_ANALYSIS_WALK_INFO *WalkInfo = (ASL_ANALYSIS_WALK_INFO *) Context;
716 ASL_METHOD_INFO *MethodInfo = WalkInfo->MethodStack;
719 switch (Op->Asl.ParseOpcode)
726 printf ("No method info for method! [%s]\n", Op->Asl.Namepath);
727 AslError (ASL_ERROR, ASL_MSG_COMPILER_INTERNAL, Op,
728 "No method info for this method");
731 return (AE_AML_INTERNAL);
740 switch (Op->Asl.ParseOpcode)
744 WalkInfo->MethodStack = MethodInfo->Next;
747 * Check if there is no return statement at the end of the
748 * method AND we can actually get there -- i.e., the execution
749 * of the method can possibly terminate without a return statement.
751 if ((!AnLastStatementIsReturn (Op)) &&
752 (!(Op->Asl.CompileFlags & OP_HAS_NO_EXIT)))
755 * No return statement, and execution can possibly exit
756 * via this path. This is equivalent to Return ()
758 MethodInfo->NumReturnNoValue++;
762 * Check for case where some return statements have a return value
763 * and some do not. Exit without a return statement is a return with
766 if (MethodInfo->NumReturnNoValue &&
767 MethodInfo->NumReturnWithValue)
769 AslError (ASL_WARNING, ASL_MSG_RETURN_TYPES, Op,
770 Op->Asl.ExternalName);
774 * If there are any RETURN() statements with no value, or there is a
775 * control path that allows the method to exit without a return value,
776 * we mark the method as a method that does not return a value. This
777 * knowledge can be used to check method invocations that expect a
780 if (MethodInfo->NumReturnNoValue)
782 if (MethodInfo->NumReturnWithValue)
784 Op->Asl.CompileFlags |= OP_METHOD_SOME_NO_RETVAL;
788 Op->Asl.CompileFlags |= OP_METHOD_NO_RETVAL;
793 * Check predefined method names for correct return behavior
794 * and correct number of arguments. Also, some special checks
795 * For GPE and _REG methods.
797 if (ApCheckForPredefinedMethod (Op, MethodInfo))
799 /* Special check for two names like _L01 and _E01 in same scope */
801 ApCheckForGpeNameConflict (Op);
804 * Special check for _REG: Must have an operation region definition
805 * within the same scope!
807 ApCheckRegMethod (Op);
810 ACPI_FREE (MethodInfo);
815 /* Special check for two names like _L01 and _E01 in same scope */
817 ApCheckForGpeNameConflict (Op);
823 * If the parent is a predefined method name, attempt to typecheck
824 * the return value. Only static types can be validated.
826 ApCheckPredefinedReturnValue (Op, MethodInfo);
829 * The parent block does not "exit" and continue execution -- the
830 * method is terminated here with the Return() statement.
832 Op->Asl.Parent->Asl.CompileFlags |= OP_HAS_NO_EXIT;
834 /* Used in the "typing" pass later */
836 Op->Asl.ParentMethod = MethodInfo->Op;
839 * If there is a peer node after the return statement, then this
840 * node is unreachable code -- i.e., it won't be executed because of
841 * the preceding Return() statement.
845 AslError (ASL_WARNING, ASL_MSG_UNREACHABLE_CODE,
852 if ((Op->Asl.CompileFlags & OP_HAS_NO_EXIT) &&
854 (Op->Asl.Next->Asl.ParseOpcode == PARSEOP_ELSE))
857 * This IF has a corresponding ELSE. The IF block has no exit,
858 * (it contains an unconditional Return)
859 * mark the ELSE block to remember this fact.
861 Op->Asl.Next->Asl.CompileFlags |= OP_IF_HAS_NO_EXIT;
867 if ((Op->Asl.CompileFlags & OP_HAS_NO_EXIT) &&
868 (Op->Asl.CompileFlags & OP_IF_HAS_NO_EXIT))
871 * This ELSE block has no exit and the corresponding IF block
872 * has no exit either. Therefore, the parent node has no exit.
874 Op->Asl.Parent->Asl.CompileFlags |= OP_HAS_NO_EXIT;
881 if ((Op->Asl.CompileFlags & OP_HAS_NO_EXIT) &&
884 /* If this node has no exit, then the parent has no exit either */
886 Op->Asl.Parent->Asl.CompileFlags |= OP_HAS_NO_EXIT;