TypeBasedAliasAnalysis.cpp File Reference

#include "llvm/Analysis/TypeBasedAliasAnalysis.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/MemoryLocation.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/InstrTypes.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Metadata.h"
#include "llvm/InitializePasses.h"
#include "llvm/Pass.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ErrorHandling.h"
#include <cassert>
#include <cstdint>

Go to the source code of this file.

Functions
static bool	isStructPathTBAA (const MDNode *MD)
	Check the first operand of the tbaa tag node, if it is a MDNode, we treat it as struct-path aware TBAA format, otherwise, we treat it as scalar TBAA format.
static bool	matchAccessTags (const MDNode *A, const MDNode *B, const MDNode **GenericTag)
	matchTags - Return true if the given couple of accesses are allowed to overlap.
static const MDNode *	getLeastCommonType (const MDNode *A, const MDNode *B)
static const MDNode *	createAccessTag (const MDNode *AccessType)
static bool	hasField (TBAAStructTypeNode BaseType, TBAAStructTypeNode FieldType)
static bool	mayBeAccessToSubobjectOf (TBAAStructTagNode BaseTag, TBAAStructTagNode SubobjectTag, const MDNode *CommonType, const MDNode **GenericTag, bool &MayAlias)
	Return true if for two given accesses, one of the accessed objects may be a subobject of the other.
	INITIALIZE_PASS (TypeBasedAAWrapperPass, "tbaa", "Type-Based Alias Analysis", false, true) ImmutablePass *llvm

Variables
static cl::opt< bool >	EnableTBAA ("enable-tbaa", cl::init(true), cl::Hidden)

Function Documentation

createAccessTag()

static const MDNode * createAccessTag ( const MDNode *  AccessType )

static

Definition at line 539 of file TypeBasedAliasAnalysis.cpp.

References llvm::ConstantAsMetadata::get(), llvm::IntegerType::get(), llvm::MDNode::get(), llvm::MDNode::getContext(), llvm::MDNode::getNumOperands(), Int64, and UINT64_MAX.

Referenced by matchAccessTags(), and mayBeAccessToSubobjectOf().

getLeastCommonType()

static const MDNode * getLeastCommonType ( const MDNode *  A, const MDNode *  B  )

static

Definition at line 483 of file TypeBasedAliasAnalysis.cpp.

References A, B, llvm::SetVector< T, Vector, Set, N >::insert(), llvm::report_fatal_error(), and llvm::SetVector< T, Vector, Set, N >::size().

Referenced by matchAccessTags().

hasField()

static bool hasField ( TBAAStructTypeNode  BaseType, TBAAStructTypeNode  FieldType  )

static

Definition at line 566 of file TypeBasedAliasAnalysis.cpp.

References hasField(), and I.

Referenced by hasField(), and mayBeAccessToSubobjectOf().

INITIALIZE_PASS()

INITIALIZE_PASS	(	TypeBasedAAWrapperPass	,
		"tbaa"	,
		"Type-Based Alias Analysis"	,
		false	,
		true
	)

Definition at line 719 of file TypeBasedAliasAnalysis.cpp.

isStructPathTBAA()

static bool isStructPathTBAA ( const MDNode *  MD )

static

Check the first operand of the tbaa tag node, if it is a MDNode, we treat it as struct-path aware TBAA format, otherwise, we treat it as scalar TBAA format.

Definition at line 369 of file TypeBasedAliasAnalysis.cpp.

References llvm::MDNode::getNumOperands(), and llvm::MDNode::getOperand().

Referenced by llvm::AAMDNodes::extendToTBAA(), llvm::TypeBasedAAResult::getMemoryEffects(), llvm::TypeBasedAAResult::getModRefInfoMask(), llvm::MDNode::isTBAAVtableAccess(), matchAccessTags(), and llvm::AAMDNodes::shiftTBAA().

matchAccessTags()

static bool matchAccessTags ( const MDNode *  A, const MDNode *  B, const MDNode **  GenericTag  )

static

matchTags - Return true if the given couple of accesses are allowed to overlap.

If

• GenericTag is not null, then on return it points to the most generic access descriptor for the given two.

Definition at line 655 of file TypeBasedAliasAnalysis.cpp.

References A, assert(), B, createAccessTag(), getLeastCommonType(), isStructPathTBAA(), and mayBeAccessToSubobjectOf().

Referenced by llvm::MDNode::getMostGenericTBAA().

mayBeAccessToSubobjectOf()

static bool mayBeAccessToSubobjectOf ( TBAAStructTagNode  BaseTag, TBAAStructTagNode  SubobjectTag, const MDNode *  CommonType, const MDNode **  GenericTag, bool &  MayAlias  )

static

Return true if for two given accesses, one of the accessed objects may be a subobject of the other.

The BaseTag and SubobjectTag parameters describe the accesses to the base object and the subobject respectively. CommonType must be the metadata node describing the common type of the accessed objects. On return, MayAlias is set to true iff these accesses may alias and Generic, if not null, points to the most generic access tag for the given two.

Definition at line 583 of file TypeBasedAliasAnalysis.cpp.

References assert(), createAccessTag(), and hasField().

Referenced by matchAccessTags().

Variable Documentation

EnableTBAA

cl::opt< bool > EnableTBAA("enable-tbaa", cl::init(true), cl::Hidden) ( "enable-tbaa"  , cl::init(true)  , cl::Hidden    )

static