705 lines
23 KiB
C++
705 lines
23 KiB
C++
//===- ARCInstKind.cpp - ObjC ARC Optimization ----------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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/// \file
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/// This file defines several utility functions used by various ARC
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/// optimizations which are IMHO too big to be in a header file.
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///
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/// WARNING: This file knows about certain library functions. It recognizes them
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/// by name, and hardwires knowledge of their semantics.
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///
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/// WARNING: This file knows about how certain Objective-C library functions are
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/// used. Naive LLVM IR transformations which would otherwise be
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/// behavior-preserving may break these assumptions.
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///
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//===----------------------------------------------------------------------===//
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#include "llvm/Analysis/ObjCARCInstKind.h"
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#include "llvm/Analysis/ObjCARCAnalysisUtils.h"
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#include "llvm/IR/Intrinsics.h"
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using namespace llvm;
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using namespace llvm::objcarc;
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raw_ostream &llvm::objcarc::operator<<(raw_ostream &OS,
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const ARCInstKind Class) {
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switch (Class) {
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case ARCInstKind::Retain:
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return OS << "ARCInstKind::Retain";
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case ARCInstKind::RetainRV:
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return OS << "ARCInstKind::RetainRV";
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case ARCInstKind::UnsafeClaimRV:
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return OS << "ARCInstKind::UnsafeClaimRV";
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case ARCInstKind::RetainBlock:
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return OS << "ARCInstKind::RetainBlock";
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case ARCInstKind::Release:
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return OS << "ARCInstKind::Release";
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case ARCInstKind::Autorelease:
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return OS << "ARCInstKind::Autorelease";
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case ARCInstKind::AutoreleaseRV:
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return OS << "ARCInstKind::AutoreleaseRV";
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case ARCInstKind::AutoreleasepoolPush:
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return OS << "ARCInstKind::AutoreleasepoolPush";
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case ARCInstKind::AutoreleasepoolPop:
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return OS << "ARCInstKind::AutoreleasepoolPop";
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case ARCInstKind::NoopCast:
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return OS << "ARCInstKind::NoopCast";
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case ARCInstKind::FusedRetainAutorelease:
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return OS << "ARCInstKind::FusedRetainAutorelease";
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case ARCInstKind::FusedRetainAutoreleaseRV:
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return OS << "ARCInstKind::FusedRetainAutoreleaseRV";
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case ARCInstKind::LoadWeakRetained:
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return OS << "ARCInstKind::LoadWeakRetained";
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case ARCInstKind::StoreWeak:
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return OS << "ARCInstKind::StoreWeak";
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case ARCInstKind::InitWeak:
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return OS << "ARCInstKind::InitWeak";
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case ARCInstKind::LoadWeak:
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return OS << "ARCInstKind::LoadWeak";
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case ARCInstKind::MoveWeak:
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return OS << "ARCInstKind::MoveWeak";
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case ARCInstKind::CopyWeak:
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return OS << "ARCInstKind::CopyWeak";
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case ARCInstKind::DestroyWeak:
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return OS << "ARCInstKind::DestroyWeak";
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case ARCInstKind::StoreStrong:
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return OS << "ARCInstKind::StoreStrong";
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case ARCInstKind::CallOrUser:
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return OS << "ARCInstKind::CallOrUser";
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case ARCInstKind::Call:
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return OS << "ARCInstKind::Call";
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case ARCInstKind::User:
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return OS << "ARCInstKind::User";
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case ARCInstKind::IntrinsicUser:
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return OS << "ARCInstKind::IntrinsicUser";
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case ARCInstKind::None:
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return OS << "ARCInstKind::None";
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}
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llvm_unreachable("Unknown instruction class!");
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}
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ARCInstKind llvm::objcarc::GetFunctionClass(const Function *F) {
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Intrinsic::ID ID = F->getIntrinsicID();
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switch (ID) {
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default:
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return ARCInstKind::CallOrUser;
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case Intrinsic::objc_autorelease:
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return ARCInstKind::Autorelease;
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case Intrinsic::objc_autoreleasePoolPop:
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return ARCInstKind::AutoreleasepoolPop;
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case Intrinsic::objc_autoreleasePoolPush:
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return ARCInstKind::AutoreleasepoolPush;
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case Intrinsic::objc_autoreleaseReturnValue:
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return ARCInstKind::AutoreleaseRV;
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case Intrinsic::objc_copyWeak:
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return ARCInstKind::CopyWeak;
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case Intrinsic::objc_destroyWeak:
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return ARCInstKind::DestroyWeak;
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case Intrinsic::objc_initWeak:
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return ARCInstKind::InitWeak;
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case Intrinsic::objc_loadWeak:
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return ARCInstKind::LoadWeak;
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case Intrinsic::objc_loadWeakRetained:
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return ARCInstKind::LoadWeakRetained;
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case Intrinsic::objc_moveWeak:
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return ARCInstKind::MoveWeak;
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case Intrinsic::objc_release:
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return ARCInstKind::Release;
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case Intrinsic::objc_retain:
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return ARCInstKind::Retain;
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case Intrinsic::objc_retainAutorelease:
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return ARCInstKind::FusedRetainAutorelease;
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case Intrinsic::objc_retainAutoreleaseReturnValue:
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return ARCInstKind::FusedRetainAutoreleaseRV;
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case Intrinsic::objc_retainAutoreleasedReturnValue:
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return ARCInstKind::RetainRV;
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case Intrinsic::objc_retainBlock:
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return ARCInstKind::RetainBlock;
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case Intrinsic::objc_storeStrong:
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return ARCInstKind::StoreStrong;
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case Intrinsic::objc_storeWeak:
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return ARCInstKind::StoreWeak;
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case Intrinsic::objc_clang_arc_use:
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return ARCInstKind::IntrinsicUser;
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case Intrinsic::objc_unsafeClaimAutoreleasedReturnValue:
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return ARCInstKind::UnsafeClaimRV;
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case Intrinsic::objc_retainedObject:
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return ARCInstKind::NoopCast;
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case Intrinsic::objc_unretainedObject:
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return ARCInstKind::NoopCast;
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case Intrinsic::objc_unretainedPointer:
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return ARCInstKind::NoopCast;
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case Intrinsic::objc_retain_autorelease:
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return ARCInstKind::FusedRetainAutorelease;
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case Intrinsic::objc_sync_enter:
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return ARCInstKind::User;
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case Intrinsic::objc_sync_exit:
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return ARCInstKind::User;
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case Intrinsic::objc_clang_arc_noop_use:
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case Intrinsic::objc_arc_annotation_topdown_bbstart:
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case Intrinsic::objc_arc_annotation_topdown_bbend:
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case Intrinsic::objc_arc_annotation_bottomup_bbstart:
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case Intrinsic::objc_arc_annotation_bottomup_bbend:
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// Ignore annotation calls. This is important to stop the
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// optimizer from treating annotations as uses which would
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// make the state of the pointers they are attempting to
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// elucidate to be incorrect.
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return ARCInstKind::None;
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}
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}
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// A list of intrinsics that we know do not use objc pointers or decrement
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// ref counts.
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static bool isInertIntrinsic(unsigned ID) {
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// TODO: Make this into a covered switch.
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switch (ID) {
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case Intrinsic::returnaddress:
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case Intrinsic::addressofreturnaddress:
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case Intrinsic::frameaddress:
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case Intrinsic::stacksave:
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case Intrinsic::stackrestore:
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case Intrinsic::vastart:
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case Intrinsic::vacopy:
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case Intrinsic::vaend:
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case Intrinsic::objectsize:
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case Intrinsic::prefetch:
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case Intrinsic::stackprotector:
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case Intrinsic::eh_return_i32:
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case Intrinsic::eh_return_i64:
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case Intrinsic::eh_typeid_for:
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case Intrinsic::eh_dwarf_cfa:
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case Intrinsic::eh_sjlj_lsda:
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case Intrinsic::eh_sjlj_functioncontext:
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case Intrinsic::init_trampoline:
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case Intrinsic::adjust_trampoline:
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case Intrinsic::lifetime_start:
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case Intrinsic::lifetime_end:
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case Intrinsic::invariant_start:
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case Intrinsic::invariant_end:
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// Don't let dbg info affect our results.
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case Intrinsic::dbg_declare:
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case Intrinsic::dbg_value:
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case Intrinsic::dbg_label:
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// Short cut: Some intrinsics obviously don't use ObjC pointers.
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return true;
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default:
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return false;
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}
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}
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// A list of intrinsics that we know do not use objc pointers or decrement
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// ref counts.
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static bool isUseOnlyIntrinsic(unsigned ID) {
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// We are conservative and even though intrinsics are unlikely to touch
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// reference counts, we white list them for safety.
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//
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// TODO: Expand this into a covered switch. There is a lot more here.
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switch (ID) {
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case Intrinsic::memcpy:
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case Intrinsic::memmove:
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case Intrinsic::memset:
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return true;
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default:
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return false;
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}
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}
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/// Determine what kind of construct V is.
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ARCInstKind llvm::objcarc::GetARCInstKind(const Value *V) {
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if (const Instruction *I = dyn_cast<Instruction>(V)) {
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// Any instruction other than bitcast and gep with a pointer operand have a
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// use of an objc pointer. Bitcasts, GEPs, Selects, PHIs transfer a pointer
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// to a subsequent use, rather than using it themselves, in this sense.
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// As a short cut, several other opcodes are known to have no pointer
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// operands of interest. And ret is never followed by a release, so it's
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// not interesting to examine.
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switch (I->getOpcode()) {
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case Instruction::Call: {
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const CallInst *CI = cast<CallInst>(I);
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// See if we have a function that we know something about.
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if (const Function *F = CI->getCalledFunction()) {
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ARCInstKind Class = GetFunctionClass(F);
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if (Class != ARCInstKind::CallOrUser)
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return Class;
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Intrinsic::ID ID = F->getIntrinsicID();
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if (isInertIntrinsic(ID))
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return ARCInstKind::None;
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if (isUseOnlyIntrinsic(ID))
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return ARCInstKind::User;
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}
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// Otherwise, be conservative.
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return GetCallSiteClass(*CI);
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}
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case Instruction::Invoke:
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// Otherwise, be conservative.
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return GetCallSiteClass(cast<InvokeInst>(*I));
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case Instruction::BitCast:
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case Instruction::GetElementPtr:
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case Instruction::Select:
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case Instruction::PHI:
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case Instruction::Ret:
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case Instruction::Br:
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case Instruction::Switch:
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case Instruction::IndirectBr:
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case Instruction::Alloca:
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case Instruction::VAArg:
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case Instruction::Add:
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case Instruction::FAdd:
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case Instruction::Sub:
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case Instruction::FSub:
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case Instruction::Mul:
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case Instruction::FMul:
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case Instruction::SDiv:
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case Instruction::UDiv:
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case Instruction::FDiv:
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case Instruction::SRem:
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case Instruction::URem:
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case Instruction::FRem:
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case Instruction::Shl:
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case Instruction::LShr:
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case Instruction::AShr:
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case Instruction::And:
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case Instruction::Or:
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case Instruction::Xor:
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case Instruction::SExt:
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case Instruction::ZExt:
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case Instruction::Trunc:
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case Instruction::IntToPtr:
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case Instruction::FCmp:
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case Instruction::FPTrunc:
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case Instruction::FPExt:
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case Instruction::FPToUI:
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case Instruction::FPToSI:
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case Instruction::UIToFP:
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case Instruction::SIToFP:
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case Instruction::InsertElement:
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case Instruction::ExtractElement:
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case Instruction::ShuffleVector:
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case Instruction::ExtractValue:
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break;
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case Instruction::ICmp:
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// Comparing a pointer with null, or any other constant, isn't an
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// interesting use, because we don't care what the pointer points to, or
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// about the values of any other dynamic reference-counted pointers.
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if (IsPotentialRetainableObjPtr(I->getOperand(1)))
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return ARCInstKind::User;
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break;
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default:
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// For anything else, check all the operands.
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// Note that this includes both operands of a Store: while the first
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// operand isn't actually being dereferenced, it is being stored to
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// memory where we can no longer track who might read it and dereference
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// it, so we have to consider it potentially used.
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for (const Use &U : I->operands())
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if (IsPotentialRetainableObjPtr(U))
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return ARCInstKind::User;
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}
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}
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// Otherwise, it's totally inert for ARC purposes.
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return ARCInstKind::None;
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}
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/// Test if the given class is a kind of user.
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bool llvm::objcarc::IsUser(ARCInstKind Class) {
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switch (Class) {
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case ARCInstKind::User:
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case ARCInstKind::CallOrUser:
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case ARCInstKind::IntrinsicUser:
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return true;
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case ARCInstKind::Retain:
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case ARCInstKind::RetainRV:
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case ARCInstKind::RetainBlock:
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case ARCInstKind::Release:
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case ARCInstKind::Autorelease:
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case ARCInstKind::AutoreleaseRV:
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case ARCInstKind::AutoreleasepoolPush:
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case ARCInstKind::AutoreleasepoolPop:
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case ARCInstKind::NoopCast:
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case ARCInstKind::FusedRetainAutorelease:
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case ARCInstKind::FusedRetainAutoreleaseRV:
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case ARCInstKind::LoadWeakRetained:
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case ARCInstKind::StoreWeak:
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case ARCInstKind::InitWeak:
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case ARCInstKind::LoadWeak:
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case ARCInstKind::MoveWeak:
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case ARCInstKind::CopyWeak:
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case ARCInstKind::DestroyWeak:
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case ARCInstKind::StoreStrong:
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case ARCInstKind::Call:
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case ARCInstKind::None:
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case ARCInstKind::UnsafeClaimRV:
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return false;
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}
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llvm_unreachable("covered switch isn't covered?");
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}
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/// Test if the given class is objc_retain or equivalent.
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bool llvm::objcarc::IsRetain(ARCInstKind Class) {
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switch (Class) {
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case ARCInstKind::Retain:
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case ARCInstKind::RetainRV:
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return true;
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// I believe we treat retain block as not a retain since it can copy its
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// block.
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case ARCInstKind::RetainBlock:
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case ARCInstKind::Release:
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case ARCInstKind::Autorelease:
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case ARCInstKind::AutoreleaseRV:
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case ARCInstKind::AutoreleasepoolPush:
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case ARCInstKind::AutoreleasepoolPop:
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case ARCInstKind::NoopCast:
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case ARCInstKind::FusedRetainAutorelease:
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case ARCInstKind::FusedRetainAutoreleaseRV:
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case ARCInstKind::LoadWeakRetained:
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case ARCInstKind::StoreWeak:
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case ARCInstKind::InitWeak:
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case ARCInstKind::LoadWeak:
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case ARCInstKind::MoveWeak:
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case ARCInstKind::CopyWeak:
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case ARCInstKind::DestroyWeak:
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case ARCInstKind::StoreStrong:
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case ARCInstKind::IntrinsicUser:
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case ARCInstKind::CallOrUser:
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case ARCInstKind::Call:
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case ARCInstKind::User:
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case ARCInstKind::None:
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case ARCInstKind::UnsafeClaimRV:
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return false;
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}
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llvm_unreachable("covered switch isn't covered?");
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}
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/// Test if the given class is objc_autorelease or equivalent.
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bool llvm::objcarc::IsAutorelease(ARCInstKind Class) {
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switch (Class) {
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case ARCInstKind::Autorelease:
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case ARCInstKind::AutoreleaseRV:
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return true;
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case ARCInstKind::Retain:
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case ARCInstKind::RetainRV:
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case ARCInstKind::UnsafeClaimRV:
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case ARCInstKind::RetainBlock:
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case ARCInstKind::Release:
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case ARCInstKind::AutoreleasepoolPush:
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case ARCInstKind::AutoreleasepoolPop:
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case ARCInstKind::NoopCast:
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case ARCInstKind::FusedRetainAutorelease:
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case ARCInstKind::FusedRetainAutoreleaseRV:
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case ARCInstKind::LoadWeakRetained:
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case ARCInstKind::StoreWeak:
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case ARCInstKind::InitWeak:
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case ARCInstKind::LoadWeak:
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case ARCInstKind::MoveWeak:
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case ARCInstKind::CopyWeak:
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case ARCInstKind::DestroyWeak:
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case ARCInstKind::StoreStrong:
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case ARCInstKind::IntrinsicUser:
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case ARCInstKind::CallOrUser:
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case ARCInstKind::Call:
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case ARCInstKind::User:
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case ARCInstKind::None:
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return false;
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}
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llvm_unreachable("covered switch isn't covered?");
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}
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/// Test if the given class represents instructions which return their
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/// argument verbatim.
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bool llvm::objcarc::IsForwarding(ARCInstKind Class) {
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switch (Class) {
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case ARCInstKind::Retain:
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case ARCInstKind::RetainRV:
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case ARCInstKind::UnsafeClaimRV:
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case ARCInstKind::Autorelease:
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case ARCInstKind::AutoreleaseRV:
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case ARCInstKind::NoopCast:
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return true;
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case ARCInstKind::RetainBlock:
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case ARCInstKind::Release:
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case ARCInstKind::AutoreleasepoolPush:
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case ARCInstKind::AutoreleasepoolPop:
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case ARCInstKind::FusedRetainAutorelease:
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case ARCInstKind::FusedRetainAutoreleaseRV:
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case ARCInstKind::LoadWeakRetained:
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case ARCInstKind::StoreWeak:
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case ARCInstKind::InitWeak:
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case ARCInstKind::LoadWeak:
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case ARCInstKind::MoveWeak:
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case ARCInstKind::CopyWeak:
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case ARCInstKind::DestroyWeak:
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case ARCInstKind::StoreStrong:
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case ARCInstKind::IntrinsicUser:
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case ARCInstKind::CallOrUser:
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case ARCInstKind::Call:
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case ARCInstKind::User:
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case ARCInstKind::None:
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return false;
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}
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llvm_unreachable("covered switch isn't covered?");
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}
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/// Test if the given class represents instructions which do nothing if
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/// passed a null pointer.
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bool llvm::objcarc::IsNoopOnNull(ARCInstKind Class) {
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switch (Class) {
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case ARCInstKind::Retain:
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case ARCInstKind::RetainRV:
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case ARCInstKind::UnsafeClaimRV:
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case ARCInstKind::Release:
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case ARCInstKind::Autorelease:
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case ARCInstKind::AutoreleaseRV:
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case ARCInstKind::RetainBlock:
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return true;
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case ARCInstKind::AutoreleasepoolPush:
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case ARCInstKind::AutoreleasepoolPop:
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case ARCInstKind::FusedRetainAutorelease:
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case ARCInstKind::FusedRetainAutoreleaseRV:
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case ARCInstKind::LoadWeakRetained:
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case ARCInstKind::StoreWeak:
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case ARCInstKind::InitWeak:
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case ARCInstKind::LoadWeak:
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case ARCInstKind::MoveWeak:
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case ARCInstKind::CopyWeak:
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case ARCInstKind::DestroyWeak:
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case ARCInstKind::StoreStrong:
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case ARCInstKind::IntrinsicUser:
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case ARCInstKind::CallOrUser:
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case ARCInstKind::Call:
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case ARCInstKind::User:
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case ARCInstKind::None:
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case ARCInstKind::NoopCast:
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return false;
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}
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|
llvm_unreachable("covered switch isn't covered?");
|
|
}
|
|
|
|
/// Test if the given class represents instructions which do nothing if
|
|
/// passed a global variable.
|
|
bool llvm::objcarc::IsNoopOnGlobal(ARCInstKind Class) {
|
|
switch (Class) {
|
|
case ARCInstKind::Retain:
|
|
case ARCInstKind::RetainRV:
|
|
case ARCInstKind::UnsafeClaimRV:
|
|
case ARCInstKind::Release:
|
|
case ARCInstKind::Autorelease:
|
|
case ARCInstKind::AutoreleaseRV:
|
|
case ARCInstKind::RetainBlock:
|
|
case ARCInstKind::FusedRetainAutorelease:
|
|
case ARCInstKind::FusedRetainAutoreleaseRV:
|
|
return true;
|
|
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::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::UnsafeClaimRV:
|
|
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::UnsafeClaimRV:
|
|
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::UnsafeClaimRV:
|
|
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::UnsafeClaimRV:
|
|
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::UnsafeClaimRV:
|
|
return true;
|
|
}
|
|
|
|
llvm_unreachable("covered switch isn't covered?");
|
|
}
|