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Revert "[CodeGen][arm64e] Add methods and data members to Address, which are needed to authenticate signed pointers (#86721)" #86898

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Merged
merged 1 commit into from
Mar 28, 2024
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Revert "[CodeGen][arm64e] Add methods and data members to Address, which are needed to authenticate signed pointers (#86721)" #86898

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10 changes: 5 additions & 5 deletions clang/lib/CodeGen/ABIInfoImpl.cpp
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Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -187,7 +187,7 @@ CodeGen::emitVoidPtrDirectVAArg(CodeGenFunction &CGF, Address VAListAddr,
CharUnits FullDirectSize = DirectSize.alignTo(SlotSize);
Address NextPtr =
CGF.Builder.CreateConstInBoundsByteGEP(Addr, FullDirectSize, "argp.next");
CGF.Builder.CreateStore(NextPtr.emitRawPointer(CGF), VAListAddr);
CGF.Builder.CreateStore(NextPtr.getPointer(), VAListAddr);

// If the argument is smaller than a slot, and this is a big-endian
// target, the argument will be right-adjusted in its slot.
Expand Down Expand Up @@ -239,8 +239,8 @@ Address CodeGen::emitMergePHI(CodeGenFunction &CGF, Address Addr1,
const llvm::Twine &Name) {
assert(Addr1.getType() == Addr2.getType());
llvm::PHINode *PHI = CGF.Builder.CreatePHI(Addr1.getType(), 2, Name);
PHI->addIncoming(Addr1.emitRawPointer(CGF), Block1);
PHI->addIncoming(Addr2.emitRawPointer(CGF), Block2);
PHI->addIncoming(Addr1.getPointer(), Block1);
PHI->addIncoming(Addr2.getPointer(), Block2);
CharUnits Align = std::min(Addr1.getAlignment(), Addr2.getAlignment());
return Address(PHI, Addr1.getElementType(), Align);
}
Expand Down Expand Up @@ -400,7 +400,7 @@ Address CodeGen::EmitVAArgInstr(CodeGenFunction &CGF, Address VAListAddr,
llvm::Type *ElementTy = CGF.ConvertTypeForMem(Ty);
llvm::Type *BaseTy = llvm::PointerType::getUnqual(ElementTy);
llvm::Value *Addr =
CGF.Builder.CreateVAArg(VAListAddr.emitRawPointer(CGF), BaseTy);
CGF.Builder.CreateVAArg(VAListAddr.getPointer(), BaseTy);
return Address(Addr, ElementTy, TyAlignForABI);
} else {
assert((AI.isDirect() || AI.isExtend()) &&
Expand All @@ -416,7 +416,7 @@ Address CodeGen::EmitVAArgInstr(CodeGenFunction &CGF, Address VAListAddr,
"Unexpected CoerceToType seen in arginfo in generic VAArg emitter!");

Address Temp = CGF.CreateMemTemp(Ty, "varet");
Val = CGF.Builder.CreateVAArg(VAListAddr.emitRawPointer(CGF),
Val = CGF.Builder.CreateVAArg(VAListAddr.getPointer(),
CGF.ConvertTypeForMem(Ty));
CGF.Builder.CreateStore(Val, Temp);
return Temp;
Expand Down
195 changes: 28 additions & 167 deletions clang/lib/CodeGen/Address.h
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Original file line number Diff line number Diff line change
Expand Up @@ -15,49 +15,35 @@
#define LLVM_CLANG_LIB_CODEGEN_ADDRESS_H

#include "clang/AST/CharUnits.h"
#include "clang/AST/Type.h"
#include "llvm/ADT/PointerIntPair.h"
#include "llvm/IR/Constants.h"
#include "llvm/Support/MathExtras.h"

namespace clang {
namespace CodeGen {

class Address;
class CGBuilderTy;
class CodeGenFunction;
class CodeGenModule;

// Indicates whether a pointer is known not to be null.
enum KnownNonNull_t { NotKnownNonNull, KnownNonNull };

/// An abstract representation of an aligned address. This is designed to be an
/// IR-level abstraction, carrying just the information necessary to perform IR
/// operations on an address like loads and stores. In particular, it doesn't
/// carry C type information or allow the representation of things like
/// bit-fields; clients working at that level should generally be using
/// `LValue`.
/// The pointer contained in this class is known to be unsigned.
class RawAddress {
/// An aligned address.
class Address {
llvm::PointerIntPair<llvm::Value *, 1, bool> PointerAndKnownNonNull;
llvm::Type *ElementType;
CharUnits Alignment;

protected:
RawAddress(std::nullptr_t) : ElementType(nullptr) {}
Address(std::nullptr_t) : ElementType(nullptr) {}

public:
RawAddress(llvm::Value *Pointer, llvm::Type *ElementType, CharUnits Alignment,
KnownNonNull_t IsKnownNonNull = NotKnownNonNull)
Address(llvm::Value *Pointer, llvm::Type *ElementType, CharUnits Alignment,
KnownNonNull_t IsKnownNonNull = NotKnownNonNull)
: PointerAndKnownNonNull(Pointer, IsKnownNonNull),
ElementType(ElementType), Alignment(Alignment) {
assert(Pointer != nullptr && "Pointer cannot be null");
assert(ElementType != nullptr && "Element type cannot be null");
}

inline RawAddress(Address Addr);

static RawAddress invalid() { return RawAddress(nullptr); }
static Address invalid() { return Address(nullptr); }
bool isValid() const {
return PointerAndKnownNonNull.getPointer() != nullptr;
}
Expand Down Expand Up @@ -94,133 +80,6 @@ class RawAddress {
return Alignment;
}

/// Return address with different element type, but same pointer and
/// alignment.
RawAddress withElementType(llvm::Type *ElemTy) const {
return RawAddress(getPointer(), ElemTy, getAlignment(), isKnownNonNull());
}

KnownNonNull_t isKnownNonNull() const {
assert(isValid());
return (KnownNonNull_t)PointerAndKnownNonNull.getInt();
}
};

/// Like RawAddress, an abstract representation of an aligned address, but the
/// pointer contained in this class is possibly signed.
class Address {
friend class CGBuilderTy;

// The boolean flag indicates whether the pointer is known to be non-null.
llvm::PointerIntPair<llvm::Value *, 1, bool> Pointer;

/// The expected IR type of the pointer. Carrying accurate element type
/// information in Address makes it more convenient to work with Address
/// values and allows frontend assertions to catch simple mistakes.
llvm::Type *ElementType = nullptr;

CharUnits Alignment;

/// Offset from the base pointer.
llvm::Value *Offset = nullptr;

llvm::Value *emitRawPointerSlow(CodeGenFunction &CGF) const;

protected:
Address(std::nullptr_t) : ElementType(nullptr) {}

public:
Address(llvm::Value *pointer, llvm::Type *elementType, CharUnits alignment,
KnownNonNull_t IsKnownNonNull = NotKnownNonNull)
: Pointer(pointer, IsKnownNonNull), ElementType(elementType),
Alignment(alignment) {
assert(pointer != nullptr && "Pointer cannot be null");
assert(elementType != nullptr && "Element type cannot be null");
assert(!alignment.isZero() && "Alignment cannot be zero");
}

Address(llvm::Value *BasePtr, llvm::Type *ElementType, CharUnits Alignment,
llvm::Value *Offset, KnownNonNull_t IsKnownNonNull = NotKnownNonNull)
: Pointer(BasePtr, IsKnownNonNull), ElementType(ElementType),
Alignment(Alignment), Offset(Offset) {}

Address(RawAddress RawAddr)
: Pointer(RawAddr.isValid() ? RawAddr.getPointer() : nullptr),
ElementType(RawAddr.isValid() ? RawAddr.getElementType() : nullptr),
Alignment(RawAddr.isValid() ? RawAddr.getAlignment()
: CharUnits::Zero()) {}

static Address invalid() { return Address(nullptr); }
bool isValid() const { return Pointer.getPointer() != nullptr; }

/// This function is used in situations where the caller is doing some sort of
/// opaque "laundering" of the pointer.
void replaceBasePointer(llvm::Value *P) {
assert(isValid() && "pointer isn't valid");
assert(P->getType() == Pointer.getPointer()->getType() &&
"Pointer's type changed");
Pointer.setPointer(P);
assert(isValid() && "pointer is invalid after replacement");
}

CharUnits getAlignment() const { return Alignment; }

void setAlignment(CharUnits Value) { Alignment = Value; }

llvm::Value *getBasePointer() const {
assert(isValid() && "pointer isn't valid");
return Pointer.getPointer();
}

/// Return the type of the pointer value.
llvm::PointerType *getType() const {
return llvm::PointerType::get(
ElementType,
llvm::cast<llvm::PointerType>(Pointer.getPointer()->getType())
->getAddressSpace());
}

/// Return the type of the values stored in this address.
llvm::Type *getElementType() const {
assert(isValid());
return ElementType;
}

/// Return the address space that this address resides in.
unsigned getAddressSpace() const { return getType()->getAddressSpace(); }

/// Return the IR name of the pointer value.
llvm::StringRef getName() const { return Pointer.getPointer()->getName(); }

// This function is called only in CGBuilderBaseTy::CreateElementBitCast.
void setElementType(llvm::Type *Ty) {
assert(hasOffset() &&
"this funcion shouldn't be called when there is no offset");
ElementType = Ty;
}

/// Whether the pointer is known not to be null.
KnownNonNull_t isKnownNonNull() const {
assert(isValid());
return (KnownNonNull_t)Pointer.getInt();
}

Address setKnownNonNull() {
assert(isValid());
Pointer.setInt(KnownNonNull);
return *this;
}

bool hasOffset() const { return Offset; }

llvm::Value *getOffset() const { return Offset; }

/// Return the pointer contained in this class after authenticating it and
/// adding offset to it if necessary.
llvm::Value *emitRawPointer(CodeGenFunction &CGF) const {
return getBasePointer();
}

/// Return address with different pointer, but same element type and
/// alignment.
Address withPointer(llvm::Value *NewPointer,
Expand All @@ -232,59 +91,61 @@ class Address {
/// Return address with different alignment, but same pointer and element
/// type.
Address withAlignment(CharUnits NewAlignment) const {
return Address(Pointer.getPointer(), getElementType(), NewAlignment,
return Address(getPointer(), getElementType(), NewAlignment,
isKnownNonNull());
}

/// Return address with different element type, but same pointer and
/// alignment.
Address withElementType(llvm::Type *ElemTy) const {
if (!hasOffset())
return Address(getBasePointer(), ElemTy, getAlignment(), nullptr,
isKnownNonNull());
Address A(*this);
A.ElementType = ElemTy;
return A;
return Address(getPointer(), ElemTy, getAlignment(), isKnownNonNull());
}
};

inline RawAddress::RawAddress(Address Addr)
: PointerAndKnownNonNull(Addr.isValid() ? Addr.getBasePointer() : nullptr,
Addr.isValid() ? Addr.isKnownNonNull()
: NotKnownNonNull),
ElementType(Addr.isValid() ? Addr.getElementType() : nullptr),
Alignment(Addr.isValid() ? Addr.getAlignment() : CharUnits::Zero()) {}
/// Whether the pointer is known not to be null.
KnownNonNull_t isKnownNonNull() const {
assert(isValid());
return (KnownNonNull_t)PointerAndKnownNonNull.getInt();
}

/// Set the non-null bit.
Address setKnownNonNull() {
assert(isValid());
PointerAndKnownNonNull.setInt(true);
return *this;
}
};

/// A specialization of Address that requires the address to be an
/// LLVM Constant.
class ConstantAddress : public RawAddress {
ConstantAddress(std::nullptr_t) : RawAddress(nullptr) {}
class ConstantAddress : public Address {
ConstantAddress(std::nullptr_t) : Address(nullptr) {}

public:
ConstantAddress(llvm::Constant *pointer, llvm::Type *elementType,
CharUnits alignment)
: RawAddress(pointer, elementType, alignment) {}
: Address(pointer, elementType, alignment) {}

static ConstantAddress invalid() {
return ConstantAddress(nullptr);
}

llvm::Constant *getPointer() const {
return llvm::cast<llvm::Constant>(RawAddress::getPointer());
return llvm::cast<llvm::Constant>(Address::getPointer());
}

ConstantAddress withElementType(llvm::Type *ElemTy) const {
return ConstantAddress(getPointer(), ElemTy, getAlignment());
}

static bool isaImpl(RawAddress addr) {
static bool isaImpl(Address addr) {
return llvm::isa<llvm::Constant>(addr.getPointer());
}
static ConstantAddress castImpl(RawAddress addr) {
static ConstantAddress castImpl(Address addr) {
return ConstantAddress(llvm::cast<llvm::Constant>(addr.getPointer()),
addr.getElementType(), addr.getAlignment());
}
};

}

// Present a minimal LLVM-like casting interface.
Expand Down
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