/*******************************************************************************
*
* Module Name: dsutils - Dispatcher utilities
*
******************************************************************************/
/*
* Copyright (C) 2000 - 2018, 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 MERCHANTIBILITY 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 "acpi.h"
#include "accommon.h"
#include "acparser.h"
#include "amlcode.h"
#include "acdispat.h"
#include "acinterp.h"
#include "acnamesp.h"
#include "acdebug.h"
#define _COMPONENT ACPI_DISPATCHER
ACPI_MODULE_NAME ("dsutils")
/*******************************************************************************
*
* FUNCTION: AcpiDsClearImplicitReturn
*
* PARAMETERS: WalkState - Current State
*
* RETURN: None.
*
* DESCRIPTION: Clear and remove a reference on an implicit return value. Used
* to delete "stale" return values (if enabled, the return value
* from every operator is saved at least momentarily, in case the
* parent method exits.)
*
******************************************************************************/
void
AcpiDsClearImplicitReturn (
ACPI_WALK_STATE *WalkState)
{
ACPI_FUNCTION_NAME (DsClearImplicitReturn);
/*
* Slack must be enabled for this feature
*/
if (!AcpiGbl_EnableInterpreterSlack)
{
return;
}
if (WalkState->ImplicitReturnObj)
{
/*
* Delete any "stale" implicit return. However, in
* complex statements, the implicit return value can be
* bubbled up several levels.
*/
ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
"Removing reference on stale implicit return obj %p\n",
WalkState->ImplicitReturnObj));
AcpiUtRemoveReference (WalkState->ImplicitReturnObj);
WalkState->ImplicitReturnObj = NULL;
}
}
#ifndef ACPI_NO_METHOD_EXECUTION
/*******************************************************************************
*
* FUNCTION: AcpiDsDoImplicitReturn
*
* PARAMETERS: ReturnDesc - The return value
* WalkState - Current State
* AddReference - True if a reference should be added to the
* return object
*
* RETURN: TRUE if implicit return enabled, FALSE otherwise
*
* DESCRIPTION: Implements the optional "implicit return". We save the result
* of every ASL operator and control method invocation in case the
* parent method exit. Before storing a new return value, we
* delete the previous return value.
*
******************************************************************************/
BOOLEAN
AcpiDsDoImplicitReturn (
ACPI_OPERAND_OBJECT *ReturnDesc,
ACPI_WALK_STATE *WalkState,
BOOLEAN AddReference)
{
ACPI_FUNCTION_NAME (DsDoImplicitReturn);
/*
* Slack must be enabled for this feature, and we must
* have a valid return object
*/
if ((!AcpiGbl_EnableInterpreterSlack) ||
(!ReturnDesc))
{
return (FALSE);
}
ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
"Result %p will be implicitly returned; Prev=%p\n",
ReturnDesc,
WalkState->ImplicitReturnObj));
/*
* Delete any "stale" implicit return value first. However, in
* complex statements, the implicit return value can be
* bubbled up several levels, so we don't clear the value if it
* is the same as the ReturnDesc.
*/
if (WalkState->ImplicitReturnObj)
{
if (WalkState->ImplicitReturnObj == ReturnDesc)
{
return (TRUE);
}
AcpiDsClearImplicitReturn (WalkState);
}
/* Save the implicit return value, add a reference if requested */
WalkState->ImplicitReturnObj = ReturnDesc;
if (AddReference)
{
AcpiUtAddReference (ReturnDesc);
}
return (TRUE);
}
/*******************************************************************************
*
* FUNCTION: AcpiDsIsResultUsed
*
* PARAMETERS: Op - Current Op
* WalkState - Current State
*
* RETURN: TRUE if result is used, FALSE otherwise
*
* DESCRIPTION: Check if a result object will be used by the parent
*
******************************************************************************/
BOOLEAN
AcpiDsIsResultUsed (
ACPI_PARSE_OBJECT *Op,
ACPI_WALK_STATE *WalkState)
{
const ACPI_OPCODE_INFO *ParentInfo;
ACPI_FUNCTION_TRACE_PTR (DsIsResultUsed, Op);
/* Must have both an Op and a Result Object */
if (!Op)
{
ACPI_ERROR ((AE_INFO, "Null Op"));
return_UINT8 (TRUE);
}
/*
* We know that this operator is not a
* Return() operator (would not come here.) The following code is the
* optional support for a so-called "implicit return". Some AML code
* assumes that the last value of the method is "implicitly" returned
* to the caller. Just save the last result as the return value.
* NOTE: this is optional because the ASL language does not actually
* support this behavior.
*/
(void) AcpiDsDoImplicitReturn (WalkState->ResultObj, WalkState, TRUE);
/*
* Now determine if the parent will use the result
*
* If there is no parent, or the parent is a ScopeOp, we are executing
* at the method level. An executing method typically has no parent,
* since each method is parsed separately. A method invoked externally
* via ExecuteControlMethod has a ScopeOp as the parent.
*/
if ((!Op->Common.Parent) ||
(Op->Common.Parent->Common.AmlOpcode == AML_SCOPE_OP))
{
/* No parent, the return value cannot possibly be used */
ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
"At Method level, result of [%s] not used\n",
AcpiPsGetOpcodeName (Op->Common.AmlOpcode)));
return_UINT8 (FALSE);
}
/* Get info on the parent. The RootOp is AML_SCOPE */
ParentInfo = AcpiPsGetOpcodeInfo (Op->Common.Parent->Common.AmlOpcode);
if (ParentInfo->Class == AML_CLASS_UNKNOWN)
{
ACPI_ERROR ((AE_INFO,
"Unknown parent opcode Op=%p", Op));
return_UINT8 (FALSE);
}
/*
* Decide what to do with the result based on the parent. If
* the parent opcode will not use the result, delete the object.
* Otherwise leave it as is, it will be deleted when it is used
* as an operand later.
*/
switch (ParentInfo->Class)
{
case AML_CLASS_CONTROL:
switch (Op->Common.Parent->Common.AmlOpcode)
{
case AML_RETURN_OP:
/* Never delete the return value associated with a return opcode */
goto ResultUsed;
case AML_IF_OP:
case AML_WHILE_OP:
/*
* If we are executing the predicate AND this is the predicate op,
* we will use the return value
*/
if ((WalkState->ControlState->Common.State ==
ACPI_CONTROL_PREDICATE_EXECUTING) &&
(WalkState->ControlState->Control.PredicateOp == Op))
{
goto ResultUsed;
}
break;
default:
/* Ignore other control opcodes */
break;
}
/* The general control opcode returns no result */
goto ResultNotUsed;
case AML_CLASS_CREATE:
/*
* These opcodes allow TermArg(s) as operands and therefore
* the operands can be method calls. The result is used.
*/
goto ResultUsed;
case AML_CLASS_NAMED_OBJECT:
if ((Op->Common.Parent->Common.AmlOpcode == AML_REGION_OP) ||
(Op->Common.Parent->Common.AmlOpcode == AML_DATA_REGION_OP) ||
(Op->Common.Parent->Common.AmlOpcode == AML_PACKAGE_OP) ||
(Op->Common.Parent->Common.AmlOpcode == AML_BUFFER_OP) ||
(Op->Common.Parent->Common.AmlOpcode == AML_VARIABLE_PACKAGE_OP) ||
(Op->Common.Parent->Common.AmlOpcode == AML_INT_EVAL_SUBTREE_OP) ||
(Op->Common.Parent->Common.AmlOpcode == AML_BANK_FIELD_OP))
{
/*
* These opcodes allow TermArg(s) as operands and therefore
* the operands can be method calls. The result is used.
*/
goto ResultUsed;
}
goto ResultNotUsed;
default:
/*
* In all other cases. the parent will actually use the return
* object, so keep it.
*/
goto ResultUsed;
}
ResultUsed:
ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
"Result of [%s] used by Parent [%s] Op=%p\n",
AcpiPsGetOpcodeName (Op->Common.AmlOpcode),
AcpiPsGetOpcodeName (Op->Common.Parent->Common.AmlOpcode), Op));
return_UINT8 (TRUE);
ResultNotUsed:
ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
"Result of [%s] not used by Parent [%s] Op=%p\n",
AcpiPsGetOpcodeName (Op->Common.AmlOpcode),
AcpiPsGetOpcodeName (Op->Common.Parent->Common.AmlOpcode), Op));
return_UINT8 (FALSE);
}
/*******************************************************************************
*
* FUNCTION: AcpiDsDeleteResultIfNotUsed
*
* PARAMETERS: Op - Current parse Op
* ResultObj - Result of the operation
* WalkState - Current state
*
* RETURN: Status
*
* DESCRIPTION: Used after interpretation of an opcode. If there is an internal
* result descriptor, check if the parent opcode will actually use
* this result. If not, delete the result now so that it will
* not become orphaned.
*
******************************************************************************/
void
AcpiDsDeleteResultIfNotUsed (
ACPI_PARSE_OBJECT *Op,
ACPI_OPERAND_OBJECT *ResultObj,
ACPI_WALK_STATE *WalkState)
{
ACPI_OPERAND_OBJECT *ObjDesc;
ACPI_STATUS Status;
ACPI_FUNCTION_TRACE_PTR (DsDeleteResultIfNotUsed, ResultObj);
if (!Op)
{
ACPI_ERROR ((AE_INFO, "Null Op"));
return_VOID;
}
if (!ResultObj)
{
return_VOID;
}
if (!AcpiDsIsResultUsed (Op, WalkState))
{
/* Must pop the result stack (ObjDesc should be equal to ResultObj) */
Status = AcpiDsResultPop (&ObjDesc, WalkState);
if (ACPI_SUCCESS (Status))
{
AcpiUtRemoveReference (ResultObj);
}
}
return_VOID;
}
/*******************************************************************************
*
* FUNCTION: AcpiDsResolveOperands
*
* PARAMETERS: WalkState - Current walk state with operands on stack
*
* RETURN: Status
*
* DESCRIPTION: Resolve all operands to their values. Used to prepare
* arguments to a control method invocation (a call from one
* method to another.)
*
******************************************************************************/
ACPI_STATUS
AcpiDsResolveOperands (
ACPI_WALK_STATE *WalkState)
{
UINT32 i;
ACPI_STATUS Status = AE_OK;
ACPI_FUNCTION_TRACE_PTR (DsResolveOperands, WalkState);
/*
* Attempt to resolve each of the valid operands
* Method arguments are passed by reference, not by value. This means
* that the actual objects are passed, not copies of the objects.
*/
for (i = 0; i < WalkState->NumOperands; i++)
{
Status = AcpiExResolveToValue (&WalkState->Operands[i], WalkState);
if (ACPI_FAILURE (Status))
{
break;
}
}
return_ACPI_STATUS (Status);
}
/*******************************************************************************
*
* FUNCTION: AcpiDsClearOperands
*
* PARAMETERS: WalkState - Current walk state with operands on stack
*
* RETURN: None
*
* DESCRIPTION: Clear all operands on the current walk state operand stack.
*
******************************************************************************/
void
AcpiDsClearOperands (
ACPI_WALK_STATE *WalkState)
{
UINT32 i;
ACPI_FUNCTION_TRACE_PTR (DsClearOperands, WalkState);
/* Remove a reference on each operand on the stack */
for (i = 0; i < WalkState->NumOperands; i++)
{
/*
* Remove a reference to all operands, including both
* "Arguments" and "Targets".
*/
AcpiUtRemoveReference (WalkState->Operands[i]);
WalkState->Operands[i] = NULL;
}
WalkState->NumOperands = 0;
return_VOID;
}
#endif
/*******************************************************************************
*
* FUNCTION: AcpiDsCreateOperand
*
* PARAMETERS: WalkState - Current walk state
* Arg - Parse object for the argument
* ArgIndex - Which argument (zero based)
*
* RETURN: Status
*
* DESCRIPTION: Translate a parse tree object that is an argument to an AML
* opcode to the equivalent interpreter object. This may include
* looking up a name or entering a new name into the internal
* namespace.
*
******************************************************************************/
ACPI_STATUS
AcpiDsCreateOperand (
ACPI_WALK_STATE *WalkState,
ACPI_PARSE_OBJECT *Arg,
UINT32 ArgIndex)
{
ACPI_STATUS Status = AE_OK;
char *NameString;
UINT32 NameLength;
ACPI_OPERAND_OBJECT *ObjDesc;
ACPI_PARSE_OBJECT *ParentOp;
UINT16 Opcode;
ACPI_INTERPRETER_MODE InterpreterMode;
const ACPI_OPCODE_INFO *OpInfo;
ACPI_FUNCTION_TRACE_PTR (DsCreateOperand, Arg);
/* A valid name must be looked up in the namespace */
if ((Arg->Common.AmlOpcode == AML_INT_NAMEPATH_OP) &&
(Arg->Common.Value.String) &&
!(Arg->Common.Flags & ACPI_PARSEOP_IN_STACK))
{
ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Getting a name: Arg=%p\n", Arg));
/* Get the entire name string from the AML stream */
Status = AcpiExGetNameString (ACPI_TYPE_ANY,
Arg->Common.Value.Buffer, &NameString, &NameLength);
if (ACPI_FAILURE (Status))
{
return_ACPI_STATUS (Status);
}
/* All prefixes have been handled, and the name is in NameString */
/*
* Special handling for BufferField declarations. This is a deferred
* opcode that unfortunately defines the field name as the last
* parameter instead of the first. We get here when we are performing
* the deferred execution, so the actual name of the field is already
* in the namespace. We don't want to attempt to look it up again
* because we may be executing in a different scope than where the
* actual opcode exists.
*/
if ((WalkState->DeferredNode) &&
(WalkState->DeferredNode->Type == ACPI_TYPE_BUFFER_FIELD) &&
(ArgIndex == (UINT32)
((WalkState->Opcode == AML_CREATE_FIELD_OP) ? 3 : 2)))
{
ObjDesc = ACPI_CAST_PTR (
ACPI_OPERAND_OBJECT, WalkState->DeferredNode);
Status = AE_OK;
}
else /* All other opcodes */
{
/*
* Differentiate between a namespace "create" operation
* versus a "lookup" operation (IMODE_LOAD_PASS2 vs.
* IMODE_EXECUTE) in order to support the creation of
* namespace objects during the execution of control methods.
*/
ParentOp = Arg->Common.Parent;
OpInfo = AcpiPsGetOpcodeInfo (ParentOp->Common.AmlOpcode);
if ((OpInfo->Flags & AML_NSNODE) &&
(ParentOp->Common.AmlOpcode != AML_INT_METHODCALL_OP) &&
(ParentOp->Common.AmlOpcode != AML_REGION_OP) &&
(ParentOp->Common.AmlOpcode != AML_INT_NAMEPATH_OP))
{
/* Enter name into namespace if not found */
InterpreterMode = ACPI_IMODE_LOAD_PASS2;
}
else
{
/* Return a failure if name not found */
InterpreterMode = ACPI_IMODE_EXECUTE;
}
Status = AcpiNsLookup (WalkState->ScopeInfo, NameString,
ACPI_TYPE_ANY, InterpreterMode,
ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE, WalkState,
ACPI_CAST_INDIRECT_PTR (ACPI_NAMESPACE_NODE, &ObjDesc));
/*
* The only case where we pass through (ignore) a NOT_FOUND
* error is for the CondRefOf opcode.
*/
if (Status == AE_NOT_FOUND)
{
if (ParentOp->Common.AmlOpcode == AML_CONDITIONAL_REF_OF_OP)
{
/*
* For the Conditional Reference op, it's OK if
* the name is not found; We just need a way to
* indicate this to the interpreter, set the
* object to the root
*/
ObjDesc = ACPI_CAST_PTR (
ACPI_OPERAND_OBJECT, AcpiGbl_RootNode);
Status = AE_OK;
}
else if (ParentOp->Common.AmlOpcode == AML_EXTERNAL_OP)
{
/*
* This opcode should never appear here. It is used only
* by AML disassemblers and is surrounded by an If(0)
* by the ASL compiler.
*
* Therefore, if we see it here, it is a serious error.
*/
Status = AE_AML_BAD_OPCODE;
}
else
{
/*
* We just plain didn't find it -- which is a
* very serious error at this point
*/
Status = AE_AML_NAME_NOT_FOUND;
}
}
if (ACPI_FAILURE (Status))
{
ACPI_ERROR_NAMESPACE (WalkState->ScopeInfo,
NameString, Status);
}
}
/* Free the namestring created above */
ACPI_FREE (NameString);
/* Check status from the lookup */
if (ACPI_FAILURE (Status))
{
return_ACPI_STATUS (Status);
}
/* Put the resulting object onto the current object stack */
Status = AcpiDsObjStackPush (ObjDesc, WalkState);
if (ACPI_FAILURE (Status))
{
return_ACPI_STATUS (Status);
}
AcpiDbDisplayArgumentObject (ObjDesc, WalkState);
}
else
{
/* Check for null name case */
if ((Arg->Common.AmlOpcode == AML_INT_NAMEPATH_OP) &&
!(Arg->Common.Flags & ACPI_PARSEOP_IN_STACK))
{
/*
* If the name is null, this means that this is an
* optional result parameter that was not specified
* in the original ASL. Create a Zero Constant for a
* placeholder. (Store to a constant is a Noop.)
*/
Opcode = AML_ZERO_OP; /* Has no arguments! */
ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
"Null namepath: Arg=%p\n", Arg));
}
else
{
Opcode = Arg->Common.AmlOpcode;
}
/* Get the object type of the argument */
OpInfo = AcpiPsGetOpcodeInfo (Opcode);
if (OpInfo->ObjectType == ACPI_TYPE_INVALID)
{
return_ACPI_STATUS (AE_NOT_IMPLEMENTED);
}
if ((OpInfo->Flags & AML_HAS_RETVAL) ||
(Arg->Common.Flags & ACPI_PARSEOP_IN_STACK))
{
/*
* Use value that was already previously returned
* by the evaluation of this argument
*/
Status = AcpiDsResultPop (&ObjDesc, WalkState);
if (ACPI_FAILURE (Status))
{
/*
* Only error is underflow, and this indicates
* a missing or null operand!
*/
ACPI_EXCEPTION ((AE_INFO, Status,
"Missing or null operand"));
return_ACPI_STATUS (Status);
}
}
else
{
/* Create an ACPI_INTERNAL_OBJECT for the argument */
ObjDesc = AcpiUtCreateInternalObject (OpInfo->ObjectType);
if (!ObjDesc)
{
return_ACPI_STATUS (AE_NO_MEMORY);
}
/* Initialize the new object */
Status = AcpiDsInitObjectFromOp (
WalkState, Arg, Opcode, &ObjDesc);
if (ACPI_FAILURE (Status))
{
AcpiUtDeleteObjectDesc (ObjDesc);
return_ACPI_STATUS (Status);
}
}
/* Put the operand object on the object stack */
Status = AcpiDsObjStackPush (ObjDesc, WalkState);
if (ACPI_FAILURE (Status))
{
return_ACPI_STATUS (Status);
}
AcpiDbDisplayArgumentObject (ObjDesc, WalkState);
}
return_ACPI_STATUS (AE_OK);
}
/*******************************************************************************
*
* FUNCTION: AcpiDsCreateOperands
*
* PARAMETERS: WalkState - Current state
* FirstArg - First argument of a parser argument tree
*
* RETURN: Status
*
* DESCRIPTION: Convert an operator's arguments from a parse tree format to
* namespace objects and place those argument object on the object
* stack in preparation for evaluation by the interpreter.
*
******************************************************************************/
ACPI_STATUS
AcpiDsCreateOperands (
ACPI_WALK_STATE *WalkState,
ACPI_PARSE_OBJECT *FirstArg)
{
ACPI_STATUS Status = AE_OK;
ACPI_PARSE_OBJECT *Arg;
ACPI_PARSE_OBJECT *Arguments[ACPI_OBJ_NUM_OPERANDS];
UINT32 ArgCount = 0;
UINT32 Index = WalkState->NumOperands;
UINT32 PrevNumOperands = WalkState->NumOperands;
UINT32 NewNumOperands;
UINT32 i;
ACPI_FUNCTION_TRACE_PTR (DsCreateOperands, FirstArg);
/* Get all arguments in the list */
Arg = FirstArg;
while (Arg)
{
if (Index >= ACPI_OBJ_NUM_OPERANDS)
{
return_ACPI_STATUS (AE_BAD_DATA);
}
Arguments[Index] = Arg;
WalkState->Operands [Index] = NULL;
/* Move on to next argument, if any */
Arg = Arg->Common.Next;
ArgCount++;
Index++;
}
ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
"NumOperands %d, ArgCount %u, Index %u\n",
WalkState->NumOperands, ArgCount, Index));
/* Create the interpreter arguments, in reverse order */
NewNumOperands = Index;
Index--;
for (i = 0; i < ArgCount; i++)
{
Arg = Arguments[Index];
WalkState->OperandIndex = (UINT8) Index;
Status = AcpiDsCreateOperand (WalkState, Arg, Index);
if (ACPI_FAILURE (Status))
{
goto Cleanup;
}
ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
"Created Arg #%u (%p) %u args total\n",
Index, Arg, ArgCount));
Index--;
}
return_ACPI_STATUS (Status);
Cleanup:
/*
* We must undo everything done above; meaning that we must
* pop everything off of the operand stack and delete those
* objects
*/
WalkState->NumOperands = i;
AcpiDsObjStackPopAndDelete (NewNumOperands, WalkState);
/* Restore operand count */
WalkState->NumOperands = PrevNumOperands;
ACPI_EXCEPTION ((AE_INFO, Status, "While creating Arg %u", Index));
return_ACPI_STATUS (Status);
}
/*****************************************************************************
*
* FUNCTION: AcpiDsEvaluateNamePath
*
* PARAMETERS: WalkState - Current state of the parse tree walk,
* the opcode of current operation should be
* AML_INT_NAMEPATH_OP
*
* RETURN: Status
*
* DESCRIPTION: Translate the -NamePath- parse tree object to the equivalent
* interpreter object, convert it to value, if needed, duplicate
* it, if needed, and push it onto the current result stack.
*
****************************************************************************/
ACPI_STATUS
AcpiDsEvaluateNamePath (
ACPI_WALK_STATE *WalkState)
{
ACPI_STATUS Status = AE_OK;
ACPI_PARSE_OBJECT *Op = WalkState->Op;
ACPI_OPERAND_OBJECT **Operand = &WalkState->Operands[0];
ACPI_OPERAND_OBJECT *NewObjDesc;
UINT8 Type;
ACPI_FUNCTION_TRACE_PTR (DsEvaluateNamePath, WalkState);
if (!Op->Common.Parent)
{
/* This happens after certain exception processing */
goto Exit;
}
if ((Op->Common.Parent->Common.AmlOpcode == AML_PACKAGE_OP) ||
(Op->Common.Parent->Common.AmlOpcode == AML_VARIABLE_PACKAGE_OP) ||
(Op->Common.Parent->Common.AmlOpcode == AML_REF_OF_OP))
{
/* TBD: Should we specify this feature as a bit of OpInfo->Flags of these opcodes? */
goto Exit;
}
Status = AcpiDsCreateOperand (WalkState, Op, 0);
if (ACPI_FAILURE (Status))
{
goto Exit;
}
if (Op->Common.Flags & ACPI_PARSEOP_TARGET)
{
NewObjDesc = *Operand;
goto PushResult;
}
Type = (*Operand)->Common.Type;
Status = AcpiExResolveToValue (Operand, WalkState);
if (ACPI_FAILURE (Status))
{
goto Exit;
}
if (Type == ACPI_TYPE_INTEGER)
{
/* It was incremented by AcpiExResolveToValue */
AcpiUtRemoveReference (*Operand);
Status = AcpiUtCopyIobjectToIobject (
*Operand, &NewObjDesc, WalkState);
if (ACPI_FAILURE (Status))
{
goto Exit;
}
}
else
{
/*
* The object either was anew created or is
* a Namespace node - don't decrement it.
*/
NewObjDesc = *Operand;
}
/* Cleanup for name-path operand */
Status = AcpiDsObjStackPop (1, WalkState);
if (ACPI_FAILURE (Status))
{
WalkState->ResultObj = NewObjDesc;
goto Exit;
}
PushResult:
WalkState->ResultObj = NewObjDesc;
Status = AcpiDsResultPush (WalkState->ResultObj, WalkState);
if (ACPI_SUCCESS (Status))
{
/* Force to take it from stack */
Op->Common.Flags |= ACPI_PARSEOP_IN_STACK;
}
Exit:
return_ACPI_STATUS (Status);
}