/******************************************************************************
*
* Module Name: aslmethod.c - Control method analysis walk
*
*****************************************************************************/
/*
* Copyright (C) 2000 - 2022, Intel Corp.
* All rights reserved.
*
* 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.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* NO WARRANTY
* 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
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR 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 DAMAGES.
*/
#include "aslcompiler.h"
#include "aslcompiler.y.h"
#include "acnamesp.h"
#include "acparser.h"
#include "amlcode.h"
#define _COMPONENT ACPI_COMPILER
ACPI_MODULE_NAME ("aslmethod")
/* Local prototypes */
static void
MtCheckNamedObjectInMethod (
ACPI_PARSE_OBJECT *Op,
ASL_METHOD_INFO *MethodInfo);
static void
MtCheckStaticOperationRegionInMethod (
ACPI_PARSE_OBJECT *Op);
/*******************************************************************************
*
* FUNCTION: MtMethodAnalysisWalkBegin
*
* PARAMETERS: ASL_WALK_CALLBACK
*
* RETURN: Status
*
* DESCRIPTION: Descending callback for the analysis walk. Check methods for:
* 1) Initialized local variables
* 2) Valid arguments
* 3) Return types
*
******************************************************************************/
ACPI_STATUS
MtMethodAnalysisWalkBegin (
ACPI_PARSE_OBJECT *Op,
UINT32 Level,
void *Context)
{
ASL_ANALYSIS_WALK_INFO *WalkInfo = (ASL_ANALYSIS_WALK_INFO *) Context;
ASL_METHOD_INFO *MethodInfo = WalkInfo->MethodStack;
ACPI_PARSE_OBJECT *Next;
UINT32 RegisterNumber;
UINT32 i;
char LocalName[] = "Local0";
char ArgName[] = "Arg0";
ACPI_PARSE_OBJECT *ArgNode;
ACPI_PARSE_OBJECT *NextType;
UINT8 ActualArgs = 0;
BOOLEAN HidExists;
BOOLEAN AdrExists;
BOOLEAN PrsExists;
BOOLEAN CrsExists;
BOOLEAN SrsExists;
BOOLEAN DisExists;
/* Build cross-reference output file if requested */
if (AslGbl_CrossReferenceOutput)
{
OtXrefWalkPart1 (Op, Level, MethodInfo);
}
switch (Op->Asl.ParseOpcode)
{
case PARSEOP_METHOD:
AslGbl_TotalMethods++;
/* Create and init method info */
MethodInfo = UtLocalCalloc (sizeof (ASL_METHOD_INFO));
MethodInfo->Next = WalkInfo->MethodStack;
MethodInfo->Op = Op;
WalkInfo->MethodStack = MethodInfo;
/*
* Special handling for _PSx methods. Dependency rules (same scope):
*
* 1) _PS0 - One of these must exist: _PS1, _PS2, _PS3
* 2) _PS1/_PS2/_PS3: A _PS0 must exist
*/
if (ACPI_COMPARE_NAMESEG (METHOD_NAME__PS0, Op->Asl.NameSeg))
{
/* For _PS0, one of _PS1/_PS2/_PS3 must exist */
if ((!ApFindNameInScope (METHOD_NAME__PS1, Op)) &&
(!ApFindNameInScope (METHOD_NAME__PS2, Op)) &&
(!ApFindNameInScope (METHOD_NAME__PS3, Op)))
{
AslError (ASL_WARNING, ASL_MSG_MISSING_DEPENDENCY, Op,
"_PS0 requires one of _PS1/_PS2/_PS3 in same scope");
}
}
else if (
ACPI_COMPARE_NAMESEG (METHOD_NAME__PS1, Op->Asl.NameSeg) ||
ACPI_COMPARE_NAMESEG (METHOD_NAME__PS2, Op->Asl.NameSeg) ||
ACPI_COMPARE_NAMESEG (METHOD_NAME__PS3, Op->Asl.NameSeg))
{
/* For _PS1/_PS2/_PS3, a _PS0 must exist */
if (!ApFindNameInScope (METHOD_NAME__PS0, Op))
{
sprintf (AslGbl_MsgBuffer,
"%4.4s requires _PS0 in same scope", Op->Asl.NameSeg);
AslError (ASL_WARNING, ASL_MSG_MISSING_DEPENDENCY, Op,
AslGbl_MsgBuffer);
}
}
/* Get the name node */
Next = Op->Asl.Child;
/* Get the NumArguments node */
Next = Next->Asl.Next;
MethodInfo->NumArguments = (UINT8)
(((UINT8) Next->Asl.Value.Integer) & 0x07);
/* Get the SerializeRule and SyncLevel nodes, ignored here */
Next = Next->Asl.Next;
MethodInfo->ShouldBeSerialized = (UINT8) Next->Asl.Value.Integer;
Next = Next->Asl.Next;
ArgNode = Next;
/* Get the ReturnType node */
Next = Next->Asl.Next;
NextType = Next->Asl.Child;
MethodInfo->ValidReturnTypes = MtProcessTypeOp (NextType);
Op->Asl.AcpiBtype |= MethodInfo->ValidReturnTypes;
/* Get the ParameterType node */
Next = Next->Asl.Next;
NextType = Next->Asl.Child;
if (!NextType)
{
/*
* The optional parameter types list was omitted at the source
* level. Use the Argument count parameter instead.
*/
ActualArgs = MethodInfo->NumArguments;
}
else
{
ActualArgs = MtProcessParameterTypeList (NextType,
MethodInfo->ValidArgTypes);
MethodInfo->NumArguments = ActualArgs;
ArgNode->Asl.Value.Integer |= ActualArgs;
}
if ((MethodInfo->NumArguments) &&
(MethodInfo->NumArguments != ActualArgs))
{
sprintf (AslGbl_MsgBuffer,
"Length = %u", ActualArgs);
AslError (ASL_ERROR, ASL_MSG_ARG_COUNT_MISMATCH,
Op->Asl.Child->Asl.Next, AslGbl_MsgBuffer);
}
/* Allow numarguments == 0 for Function() */
if ((!MethodInfo->NumArguments) && (ActualArgs))
{
MethodInfo->NumArguments = ActualArgs;
ArgNode->Asl.Value.Integer |= ActualArgs;
}
/*
* Actual arguments are initialized at method entry.
* All other ArgX "registers" can be used as locals, so we
* track their initialization.
*/
for (i = 0; i < MethodInfo->NumArguments; i++)
{
MethodInfo->ArgInitialized[i] = TRUE;
}
break;
case PARSEOP_METHODCALL:
/* Check for a recursive method call */
if (MethodInfo &&
(Op->Asl.Node == MethodInfo->Op->Asl.Node))
{
if (MethodInfo->CreatesNamedObjects)
{
/*
* This is an error, as it will fail at runtime on all ACPI
* implementations. Any named object declarations will be
* executed twice, causing failure the second time. Note,
* this is independent of whether the method is declared
* Serialized, because the same thread is attempting to
* reenter the method, and this will always succeed.
*/
AslDualParseOpError (ASL_ERROR, ASL_MSG_ILLEGAL_RECURSION, Op,
Op->Asl.Value.String, ASL_MSG_FOUND_HERE, MethodInfo->Op,
MethodInfo->Op->Asl.ExternalName);
}
else
{
/* Method does not create objects, issue a remark */
AslError (ASL_REMARK, ASL_MSG_RECURSION, Op, Op->Asl.ExternalName);
}
}
break;
case PARSEOP_LOCAL0:
case PARSEOP_LOCAL1:
case PARSEOP_LOCAL2:
case PARSEOP_LOCAL3:
case PARSEOP_LOCAL4:
case PARSEOP_LOCAL5:
case PARSEOP_LOCAL6:
case PARSEOP_LOCAL7:
if (!MethodInfo)
{
/*
* Local was used outside a control method, or there was an error
* in the method declaration.
*/
AslError (ASL_REMARK, ASL_MSG_LOCAL_OUTSIDE_METHOD,
Op, Op->Asl.ExternalName);
return (AE_ERROR);
}
RegisterNumber = (Op->Asl.AmlOpcode & 0x0007);
/*
* If the local is being used as a target, mark the local
* initialized
*/
if (Op->Asl.CompileFlags & OP_IS_TARGET)
{
MethodInfo->LocalInitialized[RegisterNumber] = TRUE;
}
/*
* Otherwise, this is a reference, check if the local
* has been previously initialized.
*
* The only operator that accepts an uninitialized value is ObjectType()
*/
else if ((!MethodInfo->LocalInitialized[RegisterNumber]) &&
(Op->Asl.Parent->Asl.ParseOpcode != PARSEOP_OBJECTTYPE))
{
LocalName[strlen (LocalName) -1] = (char) (RegisterNumber + 0x30);
AslError (ASL_ERROR, ASL_MSG_LOCAL_INIT, Op, LocalName);
}
break;
case PARSEOP_ARG0:
case PARSEOP_ARG1:
case PARSEOP_ARG2:
case PARSEOP_ARG3:
case PARSEOP_ARG4:
case PARSEOP_ARG5:
case PARSEOP_ARG6:
if (!MethodInfo)
{
/*
* Arg was used outside a control method, or there was an error
* in the method declaration.
*/
AslError (ASL_REMARK, ASL_MSG_LOCAL_OUTSIDE_METHOD,
Op, Op->Asl.ExternalName);
return (AE_ERROR);
}
RegisterNumber = (Op->Asl.AmlOpcode & 0x000F) - 8;
ArgName[strlen (ArgName) -1] = (char) (RegisterNumber + 0x30);
/*
* If the Arg is being used as a target, mark the local
* initialized
*/
if (Op->Asl.CompileFlags & OP_IS_TARGET)
{
MethodInfo->ArgInitialized[RegisterNumber] = TRUE;
}
/*
* Otherwise, this is a reference, check if the Arg
* has been previously initialized.
*
* The only operator that accepts an uninitialized value is ObjectType()
*/
else if ((!MethodInfo->ArgInitialized[RegisterNumber]) &&
(Op->Asl.Parent->Asl.ParseOpcode != PARSEOP_OBJECTTYPE))
{
AslError (ASL_ERROR, ASL_MSG_ARG_INIT, Op, ArgName);
}
/* Flag this arg if it is not a "real" argument to the method */
if (RegisterNumber >= MethodInfo->NumArguments)
{
AslError (ASL_REMARK, ASL_MSG_NOT_PARAMETER, Op, ArgName);
}
break;
case PARSEOP_RETURN:
if (!MethodInfo)
{
/*
* Probably was an error in the method declaration,
* no additional error here
*/
ACPI_WARNING ((AE_INFO, "%p, No parent method", Op));
return (AE_ERROR);
}
/*
* A child indicates a possible return value. A simple Return or
* Return() is marked with OP_IS_NULL_RETURN by the parser so
* that it is not counted as a "real" return-with-value, although
* the AML code that is actually emitted is Return(0). The AML
* definition of Return has a required parameter, so we are
* forced to convert a null return to Return(0).
*/
if ((Op->Asl.Child) &&
(Op->Asl.Child->Asl.ParseOpcode != PARSEOP_DEFAULT_ARG) &&
(!(Op->Asl.Child->Asl.CompileFlags & OP_IS_NULL_RETURN)))
{
MethodInfo->NumReturnWithValue++;
}
else
{
MethodInfo->NumReturnNoValue++;
}
break;
case PARSEOP_BREAK:
case PARSEOP_CONTINUE:
Next = Op->Asl.Parent;
while (Next)
{
if (Next->Asl.ParseOpcode == PARSEOP_WHILE)
{
break;
}
Next = Next->Asl.Parent;
}
if (!Next)
{
AslError (ASL_ERROR, ASL_MSG_NO_WHILE, Op, NULL);
}
break;
case PARSEOP_STALL:
/* We can range check if the argument is an integer */
if ((Op->Asl.Child->Asl.ParseOpcode == PARSEOP_INTEGER) &&
(Op->Asl.Child->Asl.Value.Integer > ACPI_UINT8_MAX))
{
AslError (ASL_ERROR, ASL_MSG_INVALID_TIME, Op, NULL);
}
break;
case PARSEOP_DEVICE:
/* Check usage of _HID and _ADR objects */
HidExists = ApFindNameInDeviceTree (METHOD_NAME__HID, Op);
AdrExists = ApFindNameInDeviceTree (METHOD_NAME__ADR, Op);
if (!HidExists && !AdrExists)
{
AslError (ASL_ERROR, ASL_MSG_MISSING_DEPENDENCY, Op,
"Device object requires a _HID or _ADR");
}
else if (HidExists && AdrExists)
{
/*
* According to the ACPI spec, "A device object must contain
* either an _HID object or an _ADR object, but should not contain
* both".
*/
AslError (ASL_WARNING, ASL_MSG_MULTIPLE_TYPES, Op,
"Device object requires either a _HID or _ADR, but not both");
}
/*
* Check usage of _CRS, _DIS, _PRS, and _SRS objects (July 2021).
*
* Under the Device Object:
*
* 1) If _PRS present, must have _CRS and _SRS
* 2) If _SRS present, must have _PRS (_PRS requires _CRS and _SRS)
* 3) If _DIS present, must have _SRS (_SRS requires _PRS, _PRS requires _CRS and _SRS)
* 4) If _SRS present, probably should have a _DIS (Remark only)
*/
CrsExists = ApFindNameInDeviceTree (METHOD_NAME__CRS, Op);
DisExists = ApFindNameInDeviceTree (METHOD_NAME__DIS, Op);
PrsExists = ApFindNameInDeviceTree (METHOD_NAME__PRS, Op);
SrsExists = ApFindNameInDeviceTree (METHOD_NAME__SRS, Op);
/* 1) If _PRS is present, must have a _CRS and _SRS */
if (PrsExists)
{
if (!CrsExists)
{
AslError (ASL_WARNING, ASL_MSG_MISSING_DEPENDENCY, Op,
"Device has a _PRS, missing a _CRS, required");
}
if (!SrsExists)
{
AslError (ASL_WARNING, ASL_MSG_MISSING_DEPENDENCY, Op,
"Device has a _PRS, missing a _SRS, required");
}
}
/* 2) If _SRS is present, must have _PRS (_PRS requires _CRS and _SRS) */
if ((SrsExists) && (!PrsExists))
{
AslError (ASL_WARNING, ASL_MSG_MISSING_DEPENDENCY, Op,
"Device has a _SRS, missing a _PRS, required");
}
/* 3) If _DIS is present, must have a _SRS */
if ((DisExists) && (!SrsExists))
{
AslError (ASL_WARNING, ASL_MSG_MISSING_DEPENDENCY, Op,
"Device has a _DIS, missing a _SRS, required");
}
/*
* 4) If _SRS is present, should have a _DIS (_PRS requires _CRS
* and _SRS) Remark only.
*/
if ((SrsExists) && (!DisExists))
{
AslError (ASL_REMARK, ASL_MSG_MISSING_DEPENDENCY, Op,
"Device has a _SRS, no corresponding _DIS");
}
break;
case PARSEOP_EVENT:
case PARSEOP_MUTEX:
case PARSEOP_OPERATIONREGION:
case PARSEOP_POWERRESOURCE:
case PARSEOP_PROCESSOR:
case PARSEOP_THERMALZONE:
/*
* The first operand is a name to be created in the namespace.
* Check against the reserved list.
*/
i = ApCheckForPredefinedName (Op, Op->Asl.NameSeg);
if (i < ACPI_VALID_RESERVED_NAME_MAX)
{
AslError (ASL_ERROR, ASL_MSG_RESERVED_USE,
Op, Op->Asl.ExternalName);
}
MtCheckStaticOperationRegionInMethod (Op);
break;
case PARSEOP_NAME:
/* Typecheck any predefined names statically defined with Name() */
ApCheckForPredefinedObject (Op, Op->Asl.NameSeg);
/* Special typechecking for _HID */
if (ACPI_COMPARE_NAMESEG (METHOD_NAME__HID, Op->Asl.NameSeg))
{
Next = Op->Asl.Child->Asl.Next;
AnCheckId (Next, ASL_TYPE_HID);
}
/* Special typechecking for _CID */
else if (ACPI_COMPARE_NAMESEG (METHOD_NAME__CID, Op->Asl.NameSeg))
{
Next = Op->Asl.Child->Asl.Next;
if ((Next->Asl.ParseOpcode == PARSEOP_PACKAGE) ||
(Next->Asl.ParseOpcode == PARSEOP_VAR_PACKAGE))
{
Next = Next->Asl.Child;
while (Next)
{
AnCheckId (Next, ASL_TYPE_CID);
Next = Next->Asl.Next;
}
}
else
{
AnCheckId (Next, ASL_TYPE_CID);
}
}
break;
default:
break;
}
/* Check for named object creation within a non-serialized method */
MtCheckNamedObjectInMethod (Op, MethodInfo);
return (AE_OK);
}
/*******************************************************************************
*
* FUNCTION: MtProcessTypeOp
*
* PARAMETERS: Op - Op representing a btype
*
* RETURN: Btype represented by Op
*
* DESCRIPTION: Process a parse object that represents single parameter type or
* a return type in method, function, and external declarations.
*
******************************************************************************/
UINT32
MtProcessTypeOp (
ACPI_PARSE_OBJECT *TypeOp)
{
UINT32 Btype = ACPI_BTYPE_ANY;
while (TypeOp)
{
Btype |= AnMapObjTypeToBtype (TypeOp);
TypeOp->Asl.ParseOpcode = PARSEOP_DEFAULT_ARG;
TypeOp = TypeOp->Asl.Next;
}
return (Btype);
}
/*******************************************************************************
*
* FUNCTION: MtProcessParameterTypeList
*
* PARAMETERS: Op - Op representing a btype
*
* RETURN: Btype represented by Op
*
* DESCRIPTION: Process a parse object that represents a parameter type list in
* method, function, and external declarations.
*
******************************************************************************/
UINT8
MtProcessParameterTypeList (
ACPI_PARSE_OBJECT *ParamTypeOp,
UINT32 *TypeList)
{
UINT8 ParameterCount = 0;
if (ParamTypeOp && ParamTypeOp->Asl.ParseOpcode != PARSEOP_DEFAULT_ARG)
{
/* Special case for a single parameter without braces */
TypeList[ParameterCount] =
MtProcessTypeOp (ParamTypeOp);
return (1);
}
while (ParamTypeOp)
{
TypeList[ParameterCount] =
MtProcessTypeOp (ParamTypeOp->Asl.Child);
ParameterCount++;
ParamTypeOp = ParamTypeOp->Asl.Next;
}
return (ParameterCount);
}
/*******************************************************************************
*
* FUNCTION: MtCheckNamedObjectInMethod
*
* PARAMETERS: Op - Current parser op
* MethodInfo - Info for method being parsed
*
* RETURN: None
*
* DESCRIPTION: Detect if a non-serialized method is creating a named object,
* which could possibly cause problems if two threads execute
* the method concurrently. Emit a remark in this case.
*
******************************************************************************/
static void
MtCheckNamedObjectInMethod (
ACPI_PARSE_OBJECT *Op,
ASL_METHOD_INFO *MethodInfo)
{
const ACPI_OPCODE_INFO *OpInfo;
char *ExternalPath;
/* We don't care about actual method declarations or scopes */
if ((Op->Asl.AmlOpcode == AML_METHOD_OP) ||
(Op->Asl.AmlOpcode == AML_SCOPE_OP))
{
return;
}
/* Determine if we are creating a named object within a method */
if (!MethodInfo)
{
return;
}
OpInfo = AcpiPsGetOpcodeInfo (Op->Asl.AmlOpcode);
if ((OpInfo->Class == AML_CLASS_NAMED_OBJECT) && (Op->Asl.AmlOpcode != AML_FIELD_OP))
{
/*
* 1) Mark the method as a method that creates named objects.
*
* 2) Issue a remark indicating the inefficiency of creating named
* objects within a method (Except for compiler-emitted temporary
* variables).
*
* 3) If the method is non-serialized, emit a remark that the method
* should be serialized.
*
* Reason: If a thread blocks within the method for any reason, and
* another thread enters the method, the method will fail because
* an attempt will be made to create the same object twice.
*
* Note: The Field opcode is disallowed here because Field() does not
* create a new named object.
*/
ExternalPath = AcpiNsGetNormalizedPathname (MethodInfo->Op->Asl.Node, TRUE);
/* No error for compiler temp variables (name starts with "_T_") */
if ((Op->Asl.NameSeg[0] != '_') &&
(Op->Asl.NameSeg[1] != 'T') &&
(Op->Asl.NameSeg[2] != '_'))
{
AslError (ASL_REMARK, ASL_MSG_NAMED_OBJECT_CREATION, Op,
ExternalPath);
}
MethodInfo->CreatesNamedObjects = TRUE;
if (!MethodInfo->ShouldBeSerialized)
{
AslError (ASL_REMARK, ASL_MSG_SERIALIZED_REQUIRED, MethodInfo->Op,
ExternalPath);
/* Emit message only ONCE per method */
MethodInfo->ShouldBeSerialized = TRUE;
}
if (ExternalPath)
{
ACPI_FREE (ExternalPath);
}
}
}
/*******************************************************************************
*
* FUNCTION: MtCheckStaticOperationRegionInMethod
*
* PARAMETERS: Op - Current parser op
*
* RETURN: None
*
* DESCRIPTION: Warns if an Operation Region with static address or length
* is declared inside a control method
*
******************************************************************************/
static void
MtCheckStaticOperationRegionInMethod(
ACPI_PARSE_OBJECT* Op)
{
ACPI_PARSE_OBJECT* AddressOp;
ACPI_PARSE_OBJECT* LengthOp;
if (Op->Asl.ParseOpcode != PARSEOP_OPERATIONREGION)
{
return;
}
/*
* OperationRegion should have 4 arguments defined. At this point, we
* assume that the parse tree is well-formed.
*/
AddressOp = Op->Asl.Child->Asl.Next->Asl.Next;
LengthOp = Op->Asl.Child->Asl.Next->Asl.Next->Asl.Next;
if (UtGetParentMethodOp (Op) &&
AddressOp->Asl.ParseOpcode == PARSEOP_INTEGER &&
LengthOp->Asl.ParseOpcode == PARSEOP_INTEGER)
{
/*
* At this point, a static operation region declared inside of a
* control method has been found. Throw a warning because this is
* highly inefficient.
*/
AslError(ASL_WARNING, ASL_MSG_STATIC_OPREGION_IN_METHOD, Op, NULL);
}
return;
}
/*******************************************************************************
*
* FUNCTION: MtMethodAnalysisWalkEnd
*
* PARAMETERS: ASL_WALK_CALLBACK
*
* RETURN: Status
*
* DESCRIPTION: Ascending callback for analysis walk. Complete method
* return analysis.
*
******************************************************************************/
ACPI_STATUS
MtMethodAnalysisWalkEnd (
ACPI_PARSE_OBJECT *Op,
UINT32 Level,
void *Context)
{
ASL_ANALYSIS_WALK_INFO *WalkInfo = (ASL_ANALYSIS_WALK_INFO *) Context;
ASL_METHOD_INFO *MethodInfo = WalkInfo->MethodStack;
char *ExternalPath;
switch (Op->Asl.ParseOpcode)
{
case PARSEOP_METHOD:
case PARSEOP_RETURN:
if (!MethodInfo)
{
printf ("No method info for method! [%s]\n", Op->Asl.Namepath);
AslError (ASL_ERROR, ASL_MSG_COMPILER_INTERNAL, Op,
"No method info for this method");
CmCleanupAndExit ();
return (AE_AML_INTERNAL);
}
break;
default:
break;
}
switch (Op->Asl.ParseOpcode)
{
case PARSEOP_METHOD:
WalkInfo->MethodStack = MethodInfo->Next;
/*
* Check if there is no return statement at the end of the
* method AND we can actually get there -- i.e., the execution
* of the method can possibly terminate without a return statement.
*/
if ((!AnLastStatementIsReturn (Op)) &&
(!(Op->Asl.CompileFlags & OP_HAS_NO_EXIT)))
{
/*
* No return statement, and execution can possibly exit
* via this path. This is equivalent to Return ()
*/
MethodInfo->NumReturnNoValue++;
}
/*
* Check for case where some return statements have a return value
* and some do not. Exit without a return statement is a return with
* no value
*/
if (MethodInfo->NumReturnNoValue &&
MethodInfo->NumReturnWithValue)
{
ExternalPath = AcpiNsGetNormalizedPathname (Op->Asl.Node, TRUE);
AslError (ASL_WARNING, ASL_MSG_RETURN_TYPES, Op,
ExternalPath);
if (ExternalPath)
{
ACPI_FREE (ExternalPath);
}
}
/*
* If there are any RETURN() statements with no value, or there is a
* control path that allows the method to exit without a return value,
* we mark the method as a method that does not return a value. This
* knowledge can be used to check method invocations that expect a
* returned value.
*/
if (MethodInfo->NumReturnNoValue)
{
if (MethodInfo->NumReturnWithValue)
{
Op->Asl.CompileFlags |= OP_METHOD_SOME_NO_RETVAL;
}
else
{
Op->Asl.CompileFlags |= OP_METHOD_NO_RETVAL;
}
}
/*
* Check predefined method names for correct return behavior
* and correct number of arguments. Also, some special checks
* For GPE and _REG methods.
*/
if (ApCheckForPredefinedMethod (Op, MethodInfo))
{
/* Special check for two names like _L01 and _E01 in same scope */
ApCheckForGpeNameConflict (Op);
/*
* Special check for _REG: Must have an operation region definition
* within the same scope!
*/
ApCheckRegMethod (Op);
}
ACPI_FREE (MethodInfo);
break;
case PARSEOP_NAME:
/* Special check for two names like _L01 and _E01 in same scope */
ApCheckForGpeNameConflict (Op);
break;
case PARSEOP_RETURN:
/*
* If the parent is a predefined method name, attempt to typecheck
* the return value. Only static types can be validated.
*/
ApCheckPredefinedReturnValue (Op, MethodInfo);
/*
* The parent block does not "exit" and continue execution -- the
* method is terminated here with the Return() statement.
*/
Op->Asl.Parent->Asl.CompileFlags |= OP_HAS_NO_EXIT;
/* Used in the "typing" pass later */
Op->Asl.ParentMethod = MethodInfo->Op;
/*
* If there is a peer node after the return statement, then this
* node is unreachable code -- i.e., it won't be executed because of
* the preceding Return() statement.
*/
if (Op->Asl.Next)
{
AslError (ASL_WARNING, ASL_MSG_UNREACHABLE_CODE,
Op->Asl.Next, NULL);
}
break;
case PARSEOP_IF:
if ((Op->Asl.CompileFlags & OP_HAS_NO_EXIT) &&
(Op->Asl.Next) &&
(Op->Asl.Next->Asl.ParseOpcode == PARSEOP_ELSE))
{
/*
* This IF has a corresponding ELSE. The IF block has no exit,
* (it contains an unconditional Return)
* mark the ELSE block to remember this fact.
*/
Op->Asl.Next->Asl.CompileFlags |= OP_IF_HAS_NO_EXIT;
}
break;
case PARSEOP_ELSE:
if ((Op->Asl.CompileFlags & OP_HAS_NO_EXIT) &&
(Op->Asl.CompileFlags & OP_IF_HAS_NO_EXIT))
{
/*
* This ELSE block has no exit and the corresponding IF block
* has no exit either. Therefore, the parent node has no exit.
*/
Op->Asl.Parent->Asl.CompileFlags |= OP_HAS_NO_EXIT;
}
break;
default:
if ((Op->Asl.CompileFlags & OP_HAS_NO_EXIT) &&
(Op->Asl.Parent))
{
/* If this node has no exit, then the parent has no exit either */
Op->Asl.Parent->Asl.CompileFlags |= OP_HAS_NO_EXIT;
}
break;
}
return (AE_OK);
}