forked from OSchip/llvm-project
672 lines
22 KiB
C++
672 lines
22 KiB
C++
//===- ARCInstKind.cpp - ObjC ARC Optimization ----------------------------===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
/// \file
|
|
/// This file defines several utility functions used by various ARC
|
|
/// optimizations which are IMHO too big to be in a header file.
|
|
///
|
|
/// WARNING: This file knows about certain library functions. It recognizes them
|
|
/// by name, and hardwires knowledge of their semantics.
|
|
///
|
|
/// WARNING: This file knows about how certain Objective-C library functions are
|
|
/// used. Naive LLVM IR transformations which would otherwise be
|
|
/// behavior-preserving may break these assumptions.
|
|
///
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "llvm/Analysis/ObjCARCInstKind.h"
|
|
#include "llvm/ADT/StringSwitch.h"
|
|
#include "llvm/Analysis/ObjCARCAnalysisUtils.h"
|
|
#include "llvm/IR/Intrinsics.h"
|
|
|
|
using namespace llvm;
|
|
using namespace llvm::objcarc;
|
|
|
|
raw_ostream &llvm::objcarc::operator<<(raw_ostream &OS,
|
|
const ARCInstKind Class) {
|
|
switch (Class) {
|
|
case ARCInstKind::Retain:
|
|
return OS << "ARCInstKind::Retain";
|
|
case ARCInstKind::RetainRV:
|
|
return OS << "ARCInstKind::RetainRV";
|
|
case ARCInstKind::ClaimRV:
|
|
return OS << "ARCInstKind::ClaimRV";
|
|
case ARCInstKind::RetainBlock:
|
|
return OS << "ARCInstKind::RetainBlock";
|
|
case ARCInstKind::Release:
|
|
return OS << "ARCInstKind::Release";
|
|
case ARCInstKind::Autorelease:
|
|
return OS << "ARCInstKind::Autorelease";
|
|
case ARCInstKind::AutoreleaseRV:
|
|
return OS << "ARCInstKind::AutoreleaseRV";
|
|
case ARCInstKind::AutoreleasepoolPush:
|
|
return OS << "ARCInstKind::AutoreleasepoolPush";
|
|
case ARCInstKind::AutoreleasepoolPop:
|
|
return OS << "ARCInstKind::AutoreleasepoolPop";
|
|
case ARCInstKind::NoopCast:
|
|
return OS << "ARCInstKind::NoopCast";
|
|
case ARCInstKind::FusedRetainAutorelease:
|
|
return OS << "ARCInstKind::FusedRetainAutorelease";
|
|
case ARCInstKind::FusedRetainAutoreleaseRV:
|
|
return OS << "ARCInstKind::FusedRetainAutoreleaseRV";
|
|
case ARCInstKind::LoadWeakRetained:
|
|
return OS << "ARCInstKind::LoadWeakRetained";
|
|
case ARCInstKind::StoreWeak:
|
|
return OS << "ARCInstKind::StoreWeak";
|
|
case ARCInstKind::InitWeak:
|
|
return OS << "ARCInstKind::InitWeak";
|
|
case ARCInstKind::LoadWeak:
|
|
return OS << "ARCInstKind::LoadWeak";
|
|
case ARCInstKind::MoveWeak:
|
|
return OS << "ARCInstKind::MoveWeak";
|
|
case ARCInstKind::CopyWeak:
|
|
return OS << "ARCInstKind::CopyWeak";
|
|
case ARCInstKind::DestroyWeak:
|
|
return OS << "ARCInstKind::DestroyWeak";
|
|
case ARCInstKind::StoreStrong:
|
|
return OS << "ARCInstKind::StoreStrong";
|
|
case ARCInstKind::CallOrUser:
|
|
return OS << "ARCInstKind::CallOrUser";
|
|
case ARCInstKind::Call:
|
|
return OS << "ARCInstKind::Call";
|
|
case ARCInstKind::User:
|
|
return OS << "ARCInstKind::User";
|
|
case ARCInstKind::IntrinsicUser:
|
|
return OS << "ARCInstKind::IntrinsicUser";
|
|
case ARCInstKind::None:
|
|
return OS << "ARCInstKind::None";
|
|
}
|
|
llvm_unreachable("Unknown instruction class!");
|
|
}
|
|
|
|
ARCInstKind llvm::objcarc::GetFunctionClass(const Function *F) {
|
|
|
|
Intrinsic::ID ID = F->getIntrinsicID();
|
|
switch (ID) {
|
|
default:
|
|
return ARCInstKind::CallOrUser;
|
|
case Intrinsic::objc_autorelease:
|
|
return ARCInstKind::Autorelease;
|
|
case Intrinsic::objc_autoreleasePoolPop:
|
|
return ARCInstKind::AutoreleasepoolPop;
|
|
case Intrinsic::objc_autoreleasePoolPush:
|
|
return ARCInstKind::AutoreleasepoolPush;
|
|
case Intrinsic::objc_autoreleaseReturnValue:
|
|
return ARCInstKind::AutoreleaseRV;
|
|
case Intrinsic::objc_copyWeak:
|
|
return ARCInstKind::CopyWeak;
|
|
case Intrinsic::objc_destroyWeak:
|
|
return ARCInstKind::DestroyWeak;
|
|
case Intrinsic::objc_initWeak:
|
|
return ARCInstKind::InitWeak;
|
|
case Intrinsic::objc_loadWeak:
|
|
return ARCInstKind::LoadWeak;
|
|
case Intrinsic::objc_loadWeakRetained:
|
|
return ARCInstKind::LoadWeakRetained;
|
|
case Intrinsic::objc_moveWeak:
|
|
return ARCInstKind::MoveWeak;
|
|
case Intrinsic::objc_release:
|
|
return ARCInstKind::Release;
|
|
case Intrinsic::objc_retain:
|
|
return ARCInstKind::Retain;
|
|
case Intrinsic::objc_retainAutorelease:
|
|
return ARCInstKind::FusedRetainAutorelease;
|
|
case Intrinsic::objc_retainAutoreleaseReturnValue:
|
|
return ARCInstKind::FusedRetainAutoreleaseRV;
|
|
case Intrinsic::objc_retainAutoreleasedReturnValue:
|
|
return ARCInstKind::RetainRV;
|
|
case Intrinsic::objc_retainBlock:
|
|
return ARCInstKind::RetainBlock;
|
|
case Intrinsic::objc_storeStrong:
|
|
return ARCInstKind::StoreStrong;
|
|
case Intrinsic::objc_storeWeak:
|
|
return ARCInstKind::StoreWeak;
|
|
case Intrinsic::objc_clang_arc_use:
|
|
return ARCInstKind::IntrinsicUser;
|
|
case Intrinsic::objc_unsafeClaimAutoreleasedReturnValue:
|
|
return ARCInstKind::ClaimRV;
|
|
case Intrinsic::objc_retainedObject:
|
|
return ARCInstKind::NoopCast;
|
|
case Intrinsic::objc_unretainedObject:
|
|
return ARCInstKind::NoopCast;
|
|
case Intrinsic::objc_unretainedPointer:
|
|
return ARCInstKind::NoopCast;
|
|
case Intrinsic::objc_retain_autorelease:
|
|
return ARCInstKind::FusedRetainAutorelease;
|
|
case Intrinsic::objc_sync_enter:
|
|
return ARCInstKind::User;
|
|
case Intrinsic::objc_sync_exit:
|
|
return ARCInstKind::User;
|
|
case Intrinsic::objc_arc_annotation_topdown_bbstart:
|
|
case Intrinsic::objc_arc_annotation_topdown_bbend:
|
|
case Intrinsic::objc_arc_annotation_bottomup_bbstart:
|
|
case Intrinsic::objc_arc_annotation_bottomup_bbend:
|
|
// Ignore annotation calls. This is important to stop the
|
|
// optimizer from treating annotations as uses which would
|
|
// make the state of the pointers they are attempting to
|
|
// elucidate to be incorrect.
|
|
return ARCInstKind::None;
|
|
}
|
|
}
|
|
|
|
// A whitelist of intrinsics that we know do not use objc pointers or decrement
|
|
// ref counts.
|
|
static bool isInertIntrinsic(unsigned ID) {
|
|
// TODO: Make this into a covered switch.
|
|
switch (ID) {
|
|
case Intrinsic::returnaddress:
|
|
case Intrinsic::addressofreturnaddress:
|
|
case Intrinsic::frameaddress:
|
|
case Intrinsic::stacksave:
|
|
case Intrinsic::stackrestore:
|
|
case Intrinsic::vastart:
|
|
case Intrinsic::vacopy:
|
|
case Intrinsic::vaend:
|
|
case Intrinsic::objectsize:
|
|
case Intrinsic::prefetch:
|
|
case Intrinsic::stackprotector:
|
|
case Intrinsic::eh_return_i32:
|
|
case Intrinsic::eh_return_i64:
|
|
case Intrinsic::eh_typeid_for:
|
|
case Intrinsic::eh_dwarf_cfa:
|
|
case Intrinsic::eh_sjlj_lsda:
|
|
case Intrinsic::eh_sjlj_functioncontext:
|
|
case Intrinsic::init_trampoline:
|
|
case Intrinsic::adjust_trampoline:
|
|
case Intrinsic::lifetime_start:
|
|
case Intrinsic::lifetime_end:
|
|
case Intrinsic::invariant_start:
|
|
case Intrinsic::invariant_end:
|
|
// Don't let dbg info affect our results.
|
|
case Intrinsic::dbg_declare:
|
|
case Intrinsic::dbg_value:
|
|
case Intrinsic::dbg_label:
|
|
// Short cut: Some intrinsics obviously don't use ObjC pointers.
|
|
return true;
|
|
default:
|
|
return false;
|
|
}
|
|
}
|
|
|
|
// A whitelist of intrinsics that we know do not use objc pointers or decrement
|
|
// ref counts.
|
|
static bool isUseOnlyIntrinsic(unsigned ID) {
|
|
// We are conservative and even though intrinsics are unlikely to touch
|
|
// reference counts, we white list them for safety.
|
|
//
|
|
// TODO: Expand this into a covered switch. There is a lot more here.
|
|
switch (ID) {
|
|
case Intrinsic::memcpy:
|
|
case Intrinsic::memmove:
|
|
case Intrinsic::memset:
|
|
return true;
|
|
default:
|
|
return false;
|
|
}
|
|
}
|
|
|
|
/// Determine what kind of construct V is.
|
|
ARCInstKind llvm::objcarc::GetARCInstKind(const Value *V) {
|
|
if (const Instruction *I = dyn_cast<Instruction>(V)) {
|
|
// Any instruction other than bitcast and gep with a pointer operand have a
|
|
// use of an objc pointer. Bitcasts, GEPs, Selects, PHIs transfer a pointer
|
|
// to a subsequent use, rather than using it themselves, in this sense.
|
|
// As a short cut, several other opcodes are known to have no pointer
|
|
// operands of interest. And ret is never followed by a release, so it's
|
|
// not interesting to examine.
|
|
switch (I->getOpcode()) {
|
|
case Instruction::Call: {
|
|
const CallInst *CI = cast<CallInst>(I);
|
|
// See if we have a function that we know something about.
|
|
if (const Function *F = CI->getCalledFunction()) {
|
|
ARCInstKind Class = GetFunctionClass(F);
|
|
if (Class != ARCInstKind::CallOrUser)
|
|
return Class;
|
|
Intrinsic::ID ID = F->getIntrinsicID();
|
|
if (isInertIntrinsic(ID))
|
|
return ARCInstKind::None;
|
|
if (isUseOnlyIntrinsic(ID))
|
|
return ARCInstKind::User;
|
|
}
|
|
|
|
// Otherwise, be conservative.
|
|
return GetCallSiteClass(CI);
|
|
}
|
|
case Instruction::Invoke:
|
|
// Otherwise, be conservative.
|
|
return GetCallSiteClass(cast<InvokeInst>(I));
|
|
case Instruction::BitCast:
|
|
case Instruction::GetElementPtr:
|
|
case Instruction::Select:
|
|
case Instruction::PHI:
|
|
case Instruction::Ret:
|
|
case Instruction::Br:
|
|
case Instruction::Switch:
|
|
case Instruction::IndirectBr:
|
|
case Instruction::Alloca:
|
|
case Instruction::VAArg:
|
|
case Instruction::Add:
|
|
case Instruction::FAdd:
|
|
case Instruction::Sub:
|
|
case Instruction::FSub:
|
|
case Instruction::Mul:
|
|
case Instruction::FMul:
|
|
case Instruction::SDiv:
|
|
case Instruction::UDiv:
|
|
case Instruction::FDiv:
|
|
case Instruction::SRem:
|
|
case Instruction::URem:
|
|
case Instruction::FRem:
|
|
case Instruction::Shl:
|
|
case Instruction::LShr:
|
|
case Instruction::AShr:
|
|
case Instruction::And:
|
|
case Instruction::Or:
|
|
case Instruction::Xor:
|
|
case Instruction::SExt:
|
|
case Instruction::ZExt:
|
|
case Instruction::Trunc:
|
|
case Instruction::IntToPtr:
|
|
case Instruction::FCmp:
|
|
case Instruction::FPTrunc:
|
|
case Instruction::FPExt:
|
|
case Instruction::FPToUI:
|
|
case Instruction::FPToSI:
|
|
case Instruction::UIToFP:
|
|
case Instruction::SIToFP:
|
|
case Instruction::InsertElement:
|
|
case Instruction::ExtractElement:
|
|
case Instruction::ShuffleVector:
|
|
case Instruction::ExtractValue:
|
|
break;
|
|
case Instruction::ICmp:
|
|
// Comparing a pointer with null, or any other constant, isn't an
|
|
// interesting use, because we don't care what the pointer points to, or
|
|
// about the values of any other dynamic reference-counted pointers.
|
|
if (IsPotentialRetainableObjPtr(I->getOperand(1)))
|
|
return ARCInstKind::User;
|
|
break;
|
|
default:
|
|
// For anything else, check all the operands.
|
|
// Note that this includes both operands of a Store: while the first
|
|
// operand isn't actually being dereferenced, it is being stored to
|
|
// memory where we can no longer track who might read it and dereference
|
|
// it, so we have to consider it potentially used.
|
|
for (User::const_op_iterator OI = I->op_begin(), OE = I->op_end();
|
|
OI != OE; ++OI)
|
|
if (IsPotentialRetainableObjPtr(*OI))
|
|
return ARCInstKind::User;
|
|
}
|
|
}
|
|
|
|
// Otherwise, it's totally inert for ARC purposes.
|
|
return ARCInstKind::None;
|
|
}
|
|
|
|
/// Test if the given class is a kind of user.
|
|
bool llvm::objcarc::IsUser(ARCInstKind Class) {
|
|
switch (Class) {
|
|
case ARCInstKind::User:
|
|
case ARCInstKind::CallOrUser:
|
|
case ARCInstKind::IntrinsicUser:
|
|
return true;
|
|
case ARCInstKind::Retain:
|
|
case ARCInstKind::RetainRV:
|
|
case ARCInstKind::RetainBlock:
|
|
case ARCInstKind::Release:
|
|
case ARCInstKind::Autorelease:
|
|
case ARCInstKind::AutoreleaseRV:
|
|
case ARCInstKind::AutoreleasepoolPush:
|
|
case ARCInstKind::AutoreleasepoolPop:
|
|
case ARCInstKind::NoopCast:
|
|
case ARCInstKind::FusedRetainAutorelease:
|
|
case ARCInstKind::FusedRetainAutoreleaseRV:
|
|
case ARCInstKind::LoadWeakRetained:
|
|
case ARCInstKind::StoreWeak:
|
|
case ARCInstKind::InitWeak:
|
|
case ARCInstKind::LoadWeak:
|
|
case ARCInstKind::MoveWeak:
|
|
case ARCInstKind::CopyWeak:
|
|
case ARCInstKind::DestroyWeak:
|
|
case ARCInstKind::StoreStrong:
|
|
case ARCInstKind::Call:
|
|
case ARCInstKind::None:
|
|
case ARCInstKind::ClaimRV:
|
|
return false;
|
|
}
|
|
llvm_unreachable("covered switch isn't covered?");
|
|
}
|
|
|
|
/// Test if the given class is objc_retain or equivalent.
|
|
bool llvm::objcarc::IsRetain(ARCInstKind Class) {
|
|
switch (Class) {
|
|
case ARCInstKind::Retain:
|
|
case ARCInstKind::RetainRV:
|
|
return true;
|
|
// I believe we treat retain block as not a retain since it can copy its
|
|
// block.
|
|
case ARCInstKind::RetainBlock:
|
|
case ARCInstKind::Release:
|
|
case ARCInstKind::Autorelease:
|
|
case ARCInstKind::AutoreleaseRV:
|
|
case ARCInstKind::AutoreleasepoolPush:
|
|
case ARCInstKind::AutoreleasepoolPop:
|
|
case ARCInstKind::NoopCast:
|
|
case ARCInstKind::FusedRetainAutorelease:
|
|
case ARCInstKind::FusedRetainAutoreleaseRV:
|
|
case ARCInstKind::LoadWeakRetained:
|
|
case ARCInstKind::StoreWeak:
|
|
case ARCInstKind::InitWeak:
|
|
case ARCInstKind::LoadWeak:
|
|
case ARCInstKind::MoveWeak:
|
|
case ARCInstKind::CopyWeak:
|
|
case ARCInstKind::DestroyWeak:
|
|
case ARCInstKind::StoreStrong:
|
|
case ARCInstKind::IntrinsicUser:
|
|
case ARCInstKind::CallOrUser:
|
|
case ARCInstKind::Call:
|
|
case ARCInstKind::User:
|
|
case ARCInstKind::None:
|
|
case ARCInstKind::ClaimRV:
|
|
return false;
|
|
}
|
|
llvm_unreachable("covered switch isn't covered?");
|
|
}
|
|
|
|
/// Test if the given class is objc_autorelease or equivalent.
|
|
bool llvm::objcarc::IsAutorelease(ARCInstKind Class) {
|
|
switch (Class) {
|
|
case ARCInstKind::Autorelease:
|
|
case ARCInstKind::AutoreleaseRV:
|
|
return true;
|
|
case ARCInstKind::Retain:
|
|
case ARCInstKind::RetainRV:
|
|
case ARCInstKind::ClaimRV:
|
|
case ARCInstKind::RetainBlock:
|
|
case ARCInstKind::Release:
|
|
case ARCInstKind::AutoreleasepoolPush:
|
|
case ARCInstKind::AutoreleasepoolPop:
|
|
case ARCInstKind::NoopCast:
|
|
case ARCInstKind::FusedRetainAutorelease:
|
|
case ARCInstKind::FusedRetainAutoreleaseRV:
|
|
case ARCInstKind::LoadWeakRetained:
|
|
case ARCInstKind::StoreWeak:
|
|
case ARCInstKind::InitWeak:
|
|
case ARCInstKind::LoadWeak:
|
|
case ARCInstKind::MoveWeak:
|
|
case ARCInstKind::CopyWeak:
|
|
case ARCInstKind::DestroyWeak:
|
|
case ARCInstKind::StoreStrong:
|
|
case ARCInstKind::IntrinsicUser:
|
|
case ARCInstKind::CallOrUser:
|
|
case ARCInstKind::Call:
|
|
case ARCInstKind::User:
|
|
case ARCInstKind::None:
|
|
return false;
|
|
}
|
|
llvm_unreachable("covered switch isn't covered?");
|
|
}
|
|
|
|
/// Test if the given class represents instructions which return their
|
|
/// argument verbatim.
|
|
bool llvm::objcarc::IsForwarding(ARCInstKind Class) {
|
|
switch (Class) {
|
|
case ARCInstKind::Retain:
|
|
case ARCInstKind::RetainRV:
|
|
case ARCInstKind::ClaimRV:
|
|
case ARCInstKind::Autorelease:
|
|
case ARCInstKind::AutoreleaseRV:
|
|
case ARCInstKind::NoopCast:
|
|
return true;
|
|
case ARCInstKind::RetainBlock:
|
|
case ARCInstKind::Release:
|
|
case ARCInstKind::AutoreleasepoolPush:
|
|
case ARCInstKind::AutoreleasepoolPop:
|
|
case ARCInstKind::FusedRetainAutorelease:
|
|
case ARCInstKind::FusedRetainAutoreleaseRV:
|
|
case ARCInstKind::LoadWeakRetained:
|
|
case ARCInstKind::StoreWeak:
|
|
case ARCInstKind::InitWeak:
|
|
case ARCInstKind::LoadWeak:
|
|
case ARCInstKind::MoveWeak:
|
|
case ARCInstKind::CopyWeak:
|
|
case ARCInstKind::DestroyWeak:
|
|
case ARCInstKind::StoreStrong:
|
|
case ARCInstKind::IntrinsicUser:
|
|
case ARCInstKind::CallOrUser:
|
|
case ARCInstKind::Call:
|
|
case ARCInstKind::User:
|
|
case ARCInstKind::None:
|
|
return false;
|
|
}
|
|
llvm_unreachable("covered switch isn't covered?");
|
|
}
|
|
|
|
/// Test if the given class represents instructions which do nothing if
|
|
/// passed a null pointer.
|
|
bool llvm::objcarc::IsNoopOnNull(ARCInstKind Class) {
|
|
switch (Class) {
|
|
case ARCInstKind::Retain:
|
|
case ARCInstKind::RetainRV:
|
|
case ARCInstKind::ClaimRV:
|
|
case ARCInstKind::Release:
|
|
case ARCInstKind::Autorelease:
|
|
case ARCInstKind::AutoreleaseRV:
|
|
case ARCInstKind::RetainBlock:
|
|
return true;
|
|
case ARCInstKind::AutoreleasepoolPush:
|
|
case ARCInstKind::AutoreleasepoolPop:
|
|
case ARCInstKind::FusedRetainAutorelease:
|
|
case ARCInstKind::FusedRetainAutoreleaseRV:
|
|
case ARCInstKind::LoadWeakRetained:
|
|
case ARCInstKind::StoreWeak:
|
|
case ARCInstKind::InitWeak:
|
|
case ARCInstKind::LoadWeak:
|
|
case ARCInstKind::MoveWeak:
|
|
case ARCInstKind::CopyWeak:
|
|
case ARCInstKind::DestroyWeak:
|
|
case ARCInstKind::StoreStrong:
|
|
case ARCInstKind::IntrinsicUser:
|
|
case ARCInstKind::CallOrUser:
|
|
case ARCInstKind::Call:
|
|
case ARCInstKind::User:
|
|
case ARCInstKind::None:
|
|
case ARCInstKind::NoopCast:
|
|
return false;
|
|
}
|
|
llvm_unreachable("covered switch isn't covered?");
|
|
}
|
|
|
|
/// Test if the given class represents instructions which are always safe
|
|
/// to mark with the "tail" keyword.
|
|
bool llvm::objcarc::IsAlwaysTail(ARCInstKind Class) {
|
|
// ARCInstKind::RetainBlock may be given a stack argument.
|
|
switch (Class) {
|
|
case ARCInstKind::Retain:
|
|
case ARCInstKind::RetainRV:
|
|
case ARCInstKind::ClaimRV:
|
|
case ARCInstKind::AutoreleaseRV:
|
|
return true;
|
|
case ARCInstKind::Release:
|
|
case ARCInstKind::Autorelease:
|
|
case ARCInstKind::RetainBlock:
|
|
case ARCInstKind::AutoreleasepoolPush:
|
|
case ARCInstKind::AutoreleasepoolPop:
|
|
case ARCInstKind::FusedRetainAutorelease:
|
|
case ARCInstKind::FusedRetainAutoreleaseRV:
|
|
case ARCInstKind::LoadWeakRetained:
|
|
case ARCInstKind::StoreWeak:
|
|
case ARCInstKind::InitWeak:
|
|
case ARCInstKind::LoadWeak:
|
|
case ARCInstKind::MoveWeak:
|
|
case ARCInstKind::CopyWeak:
|
|
case ARCInstKind::DestroyWeak:
|
|
case ARCInstKind::StoreStrong:
|
|
case ARCInstKind::IntrinsicUser:
|
|
case ARCInstKind::CallOrUser:
|
|
case ARCInstKind::Call:
|
|
case ARCInstKind::User:
|
|
case ARCInstKind::None:
|
|
case ARCInstKind::NoopCast:
|
|
return false;
|
|
}
|
|
llvm_unreachable("covered switch isn't covered?");
|
|
}
|
|
|
|
/// Test if the given class represents instructions which are never safe
|
|
/// to mark with the "tail" keyword.
|
|
bool llvm::objcarc::IsNeverTail(ARCInstKind Class) {
|
|
/// It is never safe to tail call objc_autorelease since by tail calling
|
|
/// objc_autorelease: fast autoreleasing causing our object to be potentially
|
|
/// reclaimed from the autorelease pool which violates the semantics of
|
|
/// __autoreleasing types in ARC.
|
|
switch (Class) {
|
|
case ARCInstKind::Autorelease:
|
|
return true;
|
|
case ARCInstKind::Retain:
|
|
case ARCInstKind::RetainRV:
|
|
case ARCInstKind::ClaimRV:
|
|
case ARCInstKind::AutoreleaseRV:
|
|
case ARCInstKind::Release:
|
|
case ARCInstKind::RetainBlock:
|
|
case ARCInstKind::AutoreleasepoolPush:
|
|
case ARCInstKind::AutoreleasepoolPop:
|
|
case ARCInstKind::FusedRetainAutorelease:
|
|
case ARCInstKind::FusedRetainAutoreleaseRV:
|
|
case ARCInstKind::LoadWeakRetained:
|
|
case ARCInstKind::StoreWeak:
|
|
case ARCInstKind::InitWeak:
|
|
case ARCInstKind::LoadWeak:
|
|
case ARCInstKind::MoveWeak:
|
|
case ARCInstKind::CopyWeak:
|
|
case ARCInstKind::DestroyWeak:
|
|
case ARCInstKind::StoreStrong:
|
|
case ARCInstKind::IntrinsicUser:
|
|
case ARCInstKind::CallOrUser:
|
|
case ARCInstKind::Call:
|
|
case ARCInstKind::User:
|
|
case ARCInstKind::None:
|
|
case ARCInstKind::NoopCast:
|
|
return false;
|
|
}
|
|
llvm_unreachable("covered switch isn't covered?");
|
|
}
|
|
|
|
/// Test if the given class represents instructions which are always safe
|
|
/// to mark with the nounwind attribute.
|
|
bool llvm::objcarc::IsNoThrow(ARCInstKind Class) {
|
|
// objc_retainBlock is not nounwind because it calls user copy constructors
|
|
// which could theoretically throw.
|
|
switch (Class) {
|
|
case ARCInstKind::Retain:
|
|
case ARCInstKind::RetainRV:
|
|
case ARCInstKind::ClaimRV:
|
|
case ARCInstKind::Release:
|
|
case ARCInstKind::Autorelease:
|
|
case ARCInstKind::AutoreleaseRV:
|
|
case ARCInstKind::AutoreleasepoolPush:
|
|
case ARCInstKind::AutoreleasepoolPop:
|
|
return true;
|
|
case ARCInstKind::RetainBlock:
|
|
case ARCInstKind::FusedRetainAutorelease:
|
|
case ARCInstKind::FusedRetainAutoreleaseRV:
|
|
case ARCInstKind::LoadWeakRetained:
|
|
case ARCInstKind::StoreWeak:
|
|
case ARCInstKind::InitWeak:
|
|
case ARCInstKind::LoadWeak:
|
|
case ARCInstKind::MoveWeak:
|
|
case ARCInstKind::CopyWeak:
|
|
case ARCInstKind::DestroyWeak:
|
|
case ARCInstKind::StoreStrong:
|
|
case ARCInstKind::IntrinsicUser:
|
|
case ARCInstKind::CallOrUser:
|
|
case ARCInstKind::Call:
|
|
case ARCInstKind::User:
|
|
case ARCInstKind::None:
|
|
case ARCInstKind::NoopCast:
|
|
return false;
|
|
}
|
|
llvm_unreachable("covered switch isn't covered?");
|
|
}
|
|
|
|
/// Test whether the given instruction can autorelease any pointer or cause an
|
|
/// autoreleasepool pop.
|
|
///
|
|
/// This means that it *could* interrupt the RV optimization.
|
|
bool llvm::objcarc::CanInterruptRV(ARCInstKind Class) {
|
|
switch (Class) {
|
|
case ARCInstKind::AutoreleasepoolPop:
|
|
case ARCInstKind::CallOrUser:
|
|
case ARCInstKind::Call:
|
|
case ARCInstKind::Autorelease:
|
|
case ARCInstKind::AutoreleaseRV:
|
|
case ARCInstKind::FusedRetainAutorelease:
|
|
case ARCInstKind::FusedRetainAutoreleaseRV:
|
|
return true;
|
|
case ARCInstKind::Retain:
|
|
case ARCInstKind::RetainRV:
|
|
case ARCInstKind::ClaimRV:
|
|
case ARCInstKind::Release:
|
|
case ARCInstKind::AutoreleasepoolPush:
|
|
case ARCInstKind::RetainBlock:
|
|
case ARCInstKind::LoadWeakRetained:
|
|
case ARCInstKind::StoreWeak:
|
|
case ARCInstKind::InitWeak:
|
|
case ARCInstKind::LoadWeak:
|
|
case ARCInstKind::MoveWeak:
|
|
case ARCInstKind::CopyWeak:
|
|
case ARCInstKind::DestroyWeak:
|
|
case ARCInstKind::StoreStrong:
|
|
case ARCInstKind::IntrinsicUser:
|
|
case ARCInstKind::User:
|
|
case ARCInstKind::None:
|
|
case ARCInstKind::NoopCast:
|
|
return false;
|
|
}
|
|
llvm_unreachable("covered switch isn't covered?");
|
|
}
|
|
|
|
bool llvm::objcarc::CanDecrementRefCount(ARCInstKind Kind) {
|
|
switch (Kind) {
|
|
case ARCInstKind::Retain:
|
|
case ARCInstKind::RetainRV:
|
|
case ARCInstKind::Autorelease:
|
|
case ARCInstKind::AutoreleaseRV:
|
|
case ARCInstKind::NoopCast:
|
|
case ARCInstKind::FusedRetainAutorelease:
|
|
case ARCInstKind::FusedRetainAutoreleaseRV:
|
|
case ARCInstKind::IntrinsicUser:
|
|
case ARCInstKind::User:
|
|
case ARCInstKind::None:
|
|
return false;
|
|
|
|
// The cases below are conservative.
|
|
|
|
// RetainBlock can result in user defined copy constructors being called
|
|
// implying releases may occur.
|
|
case ARCInstKind::RetainBlock:
|
|
case ARCInstKind::Release:
|
|
case ARCInstKind::AutoreleasepoolPush:
|
|
case ARCInstKind::AutoreleasepoolPop:
|
|
case ARCInstKind::LoadWeakRetained:
|
|
case ARCInstKind::StoreWeak:
|
|
case ARCInstKind::InitWeak:
|
|
case ARCInstKind::LoadWeak:
|
|
case ARCInstKind::MoveWeak:
|
|
case ARCInstKind::CopyWeak:
|
|
case ARCInstKind::DestroyWeak:
|
|
case ARCInstKind::StoreStrong:
|
|
case ARCInstKind::CallOrUser:
|
|
case ARCInstKind::Call:
|
|
case ARCInstKind::ClaimRV:
|
|
return true;
|
|
}
|
|
|
|
llvm_unreachable("covered switch isn't covered?");
|
|
}
|