diff options
Diffstat (limited to 'lib/Transforms/ObjCARC/ARCInstKind.h')
| -rw-r--r-- | lib/Transforms/ObjCARC/ARCInstKind.h | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/lib/Transforms/ObjCARC/ARCInstKind.h b/lib/Transforms/ObjCARC/ARCInstKind.h new file mode 100644 index 0000000..636c65c --- /dev/null +++ b/lib/Transforms/ObjCARC/ARCInstKind.h @@ -0,0 +1,123 @@ +//===--- ARCInstKind.h - ARC instruction equivalence classes -*- C++ -*----===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_LIB_TRANSFORMS_OBJCARC_ARCINSTKIND_H +#define LLVM_LIB_TRANSFORMS_OBJCARC_ARCINSTKIND_H + +#include "llvm/IR/Instructions.h" +#include "llvm/IR/Function.h" + +namespace llvm { +namespace objcarc { + +/// \enum ARCInstKind +/// +/// \brief Equivalence classes of instructions in the ARC Model. +/// +/// Since we do not have "instructions" to represent ARC concepts in LLVM IR, +/// we instead operate on equivalence classes of instructions. +/// +/// TODO: This should be split into two enums: a runtime entry point enum +/// (possibly united with the ARCRuntimeEntrypoint class) and an enum that deals +/// with effects of instructions in the ARC model (which would handle the notion +/// of a User or CallOrUser). +enum class ARCInstKind { + Retain, ///< objc_retain + RetainRV, ///< objc_retainAutoreleasedReturnValue + RetainBlock, ///< objc_retainBlock + Release, ///< objc_release + Autorelease, ///< objc_autorelease + AutoreleaseRV, ///< objc_autoreleaseReturnValue + AutoreleasepoolPush, ///< objc_autoreleasePoolPush + AutoreleasepoolPop, ///< objc_autoreleasePoolPop + NoopCast, ///< objc_retainedObject, etc. + FusedRetainAutorelease, ///< objc_retainAutorelease + FusedRetainAutoreleaseRV, ///< objc_retainAutoreleaseReturnValue + LoadWeakRetained, ///< objc_loadWeakRetained (primitive) + StoreWeak, ///< objc_storeWeak (primitive) + InitWeak, ///< objc_initWeak (derived) + LoadWeak, ///< objc_loadWeak (derived) + MoveWeak, ///< objc_moveWeak (derived) + CopyWeak, ///< objc_copyWeak (derived) + DestroyWeak, ///< objc_destroyWeak (derived) + StoreStrong, ///< objc_storeStrong (derived) + IntrinsicUser, ///< clang.arc.use + CallOrUser, ///< could call objc_release and/or "use" pointers + Call, ///< could call objc_release + User, ///< could "use" a pointer + None ///< anything that is inert from an ARC perspective. +}; + +raw_ostream &operator<<(raw_ostream &OS, const ARCInstKind Class); + +/// \brief Test if the given class is a kind of user. +bool IsUser(ARCInstKind Class); + +/// \brief Test if the given class is objc_retain or equivalent. +bool IsRetain(ARCInstKind Class); + +/// \brief Test if the given class is objc_autorelease or equivalent. +bool IsAutorelease(ARCInstKind Class); + +/// \brief Test if the given class represents instructions which return their +/// argument verbatim. +bool IsForwarding(ARCInstKind Class); + +/// \brief Test if the given class represents instructions which do nothing if +/// passed a null pointer. +bool IsNoopOnNull(ARCInstKind Class); + +/// \brief Test if the given class represents instructions which are always safe +/// to mark with the "tail" keyword. +bool IsAlwaysTail(ARCInstKind Class); + +/// \brief Test if the given class represents instructions which are never safe +/// to mark with the "tail" keyword. +bool IsNeverTail(ARCInstKind Class); + +/// \brief Test if the given class represents instructions which are always safe +/// to mark with the nounwind attribute. +bool IsNoThrow(ARCInstKind Class); + +/// Test whether the given instruction can autorelease any pointer or cause an +/// autoreleasepool pop. +bool CanInterruptRV(ARCInstKind Class); + +/// \brief Determine if F is one of the special known Functions. If it isn't, +/// return ARCInstKind::CallOrUser. +ARCInstKind GetFunctionClass(const Function *F); + +/// \brief Determine which objc runtime call instruction class V belongs to. +/// +/// This is similar to GetARCInstKind except that it only detects objc +/// runtime calls. This allows it to be faster. +/// +static inline ARCInstKind GetBasicARCInstKind(const Value *V) { + if (const CallInst *CI = dyn_cast<CallInst>(V)) { + if (const Function *F = CI->getCalledFunction()) + return GetFunctionClass(F); + // Otherwise, be conservative. + return ARCInstKind::CallOrUser; + } + + // Otherwise, be conservative. + return isa<InvokeInst>(V) ? ARCInstKind::CallOrUser : ARCInstKind::User; +} + +/// Map V to its ARCInstKind equivalence class. +ARCInstKind GetARCInstKind(const Value *V); + +/// Returns false if conservatively we can prove that any instruction mapped to +/// this kind can not decrement ref counts. Returns true otherwise. +bool CanDecrementRefCount(ARCInstKind Kind); + +} // end namespace objcarc +} // end namespace llvm + +#endif |