mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-12-14 11:32:34 +00:00
24ee447d0f
This is different from CanAlterRefCount since CanDecrementRefCount is attempting to prove specifically whether or not an instruction can decrement instead of the more general question of whether it can decrement or increment. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229936 91177308-0d34-0410-b5e6-96231b3b80d8
646 lines
23 KiB
C++
646 lines
23 KiB
C++
//===- ARCInstKind.cpp - ObjC ARC Optimization ----------------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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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 "ObjCARC.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::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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Function::const_arg_iterator AI = F->arg_begin(), AE = F->arg_end();
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// No (mandatory) arguments.
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if (AI == AE)
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return StringSwitch<ARCInstKind>(F->getName())
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.Case("objc_autoreleasePoolPush", ARCInstKind::AutoreleasepoolPush)
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.Case("clang.arc.use", ARCInstKind::IntrinsicUser)
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.Default(ARCInstKind::CallOrUser);
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// One argument.
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const Argument *A0 = AI++;
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if (AI == AE)
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// Argument is a pointer.
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if (PointerType *PTy = dyn_cast<PointerType>(A0->getType())) {
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Type *ETy = PTy->getElementType();
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// Argument is i8*.
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if (ETy->isIntegerTy(8))
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return StringSwitch<ARCInstKind>(F->getName())
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.Case("objc_retain", ARCInstKind::Retain)
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.Case("objc_retainAutoreleasedReturnValue", ARCInstKind::RetainRV)
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.Case("objc_retainBlock", ARCInstKind::RetainBlock)
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.Case("objc_release", ARCInstKind::Release)
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.Case("objc_autorelease", ARCInstKind::Autorelease)
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.Case("objc_autoreleaseReturnValue", ARCInstKind::AutoreleaseRV)
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.Case("objc_autoreleasePoolPop", ARCInstKind::AutoreleasepoolPop)
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.Case("objc_retainedObject", ARCInstKind::NoopCast)
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.Case("objc_unretainedObject", ARCInstKind::NoopCast)
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.Case("objc_unretainedPointer", ARCInstKind::NoopCast)
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.Case("objc_retain_autorelease",
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ARCInstKind::FusedRetainAutorelease)
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.Case("objc_retainAutorelease", ARCInstKind::FusedRetainAutorelease)
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.Case("objc_retainAutoreleaseReturnValue",
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ARCInstKind::FusedRetainAutoreleaseRV)
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.Case("objc_sync_enter", ARCInstKind::User)
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.Case("objc_sync_exit", ARCInstKind::User)
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.Default(ARCInstKind::CallOrUser);
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// Argument is i8**
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if (PointerType *Pte = dyn_cast<PointerType>(ETy))
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if (Pte->getElementType()->isIntegerTy(8))
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return StringSwitch<ARCInstKind>(F->getName())
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.Case("objc_loadWeakRetained", ARCInstKind::LoadWeakRetained)
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.Case("objc_loadWeak", ARCInstKind::LoadWeak)
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.Case("objc_destroyWeak", ARCInstKind::DestroyWeak)
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.Default(ARCInstKind::CallOrUser);
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}
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// Two arguments, first is i8**.
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const Argument *A1 = AI++;
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if (AI == AE)
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if (PointerType *PTy = dyn_cast<PointerType>(A0->getType()))
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if (PointerType *Pte = dyn_cast<PointerType>(PTy->getElementType()))
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if (Pte->getElementType()->isIntegerTy(8))
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if (PointerType *PTy1 = dyn_cast<PointerType>(A1->getType())) {
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Type *ETy1 = PTy1->getElementType();
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// Second argument is i8*
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if (ETy1->isIntegerTy(8))
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return StringSwitch<ARCInstKind>(F->getName())
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.Case("objc_storeWeak", ARCInstKind::StoreWeak)
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.Case("objc_initWeak", ARCInstKind::InitWeak)
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.Case("objc_storeStrong", ARCInstKind::StoreStrong)
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.Default(ARCInstKind::CallOrUser);
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// Second argument is i8**.
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if (PointerType *Pte1 = dyn_cast<PointerType>(ETy1))
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if (Pte1->getElementType()->isIntegerTy(8))
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return StringSwitch<ARCInstKind>(F->getName())
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.Case("objc_moveWeak", ARCInstKind::MoveWeak)
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.Case("objc_copyWeak", ARCInstKind::CopyWeak)
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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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.Case("llvm.arc.annotation.topdown.bbstart",
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ARCInstKind::None)
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.Case("llvm.arc.annotation.topdown.bbend",
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ARCInstKind::None)
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.Case("llvm.arc.annotation.bottomup.bbstart",
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ARCInstKind::None)
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.Case("llvm.arc.annotation.bottomup.bbend",
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ARCInstKind::None)
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.Default(ARCInstKind::CallOrUser);
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}
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// Anything else.
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return ARCInstKind::CallOrUser;
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}
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/// \brief 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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// Check for calls to special functions.
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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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// None of the intrinsic functions do objc_release. For intrinsics, the
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// only question is whether or not they may be users.
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switch (F->getIntrinsicID()) {
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case Intrinsic::returnaddress:
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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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// Short cut: Some intrinsics obviously don't use ObjC pointers.
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return ARCInstKind::None;
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default:
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break;
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}
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}
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return GetCallSiteClass(CI);
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}
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case Instruction::Invoke:
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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 (User::const_op_iterator OI = I->op_begin(), OE = I->op_end();
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OI != OE; ++OI)
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if (IsPotentialRetainableObjPtr(*OI))
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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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/// \brief 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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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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/// \brief 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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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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/// \brief 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::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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/// \brief 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::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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/// \brief 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::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:
|
|
return false;
|
|
}
|
|
llvm_unreachable("covered switch isn't covered?");
|
|
}
|
|
|
|
/// \brief 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::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?");
|
|
}
|
|
|
|
/// \brief 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::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?");
|
|
}
|
|
|
|
/// \brief 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::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::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:
|
|
return true;
|
|
}
|
|
|
|
llvm_unreachable("covered switch isn't covered?");
|
|
}
|