| 1 | //===- ObjCARCAnalysisUtils.cpp -------------------------------------------===// |
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| 2 | // |
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| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
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| 4 | // See https://llvm.org/LICENSE.txt for license information. |
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| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
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| 6 | // |
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| 7 | //===----------------------------------------------------------------------===// |
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| 8 | // |
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| 9 | // This file implements common infrastructure for libLLVMObjCARCOpts.a, which |
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| 10 | // implements several scalar transformations over the LLVM intermediate |
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| 11 | // representation, including the C bindings for that library. |
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| 12 | // |
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| 13 | //===----------------------------------------------------------------------===// |
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| 14 | |
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| 15 | #include "llvm/Analysis/ObjCARCAnalysisUtils.h" |
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| 16 | #include "llvm/Analysis/AliasAnalysis.h" |
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| 17 | #include "llvm/Support/CommandLine.h" |
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| 18 | |
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| 19 | using namespace llvm; |
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| 20 | using namespace llvm::objcarc; |
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| 21 | |
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| 22 | /// A handy option to enable/disable all ARC Optimizations. |
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| 23 | bool llvm::objcarc::EnableARCOpts; |
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| 24 | static cl::opt<bool, true> EnableARCOptimizations( |
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| 25 | "enable-objc-arc-opts" , cl::desc("enable/disable all ARC Optimizations" ), |
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| 26 | cl::location(L&: EnableARCOpts), cl::init(Val: true), cl::Hidden); |
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| 27 | |
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| 28 | bool llvm::objcarc::IsPotentialRetainableObjPtr(const Value *Op, |
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| 29 | AAResults &AA) { |
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| 30 | // First make the rudimentary check. |
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| 31 | if (!IsPotentialRetainableObjPtr(Op)) |
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| 32 | return false; |
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| 33 | |
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| 34 | // Objects in constant memory are not reference-counted. |
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| 35 | if (AA.pointsToConstantMemory(P: Op)) |
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| 36 | return false; |
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| 37 | |
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| 38 | // Pointers in constant memory are not pointing to reference-counted objects. |
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| 39 | if (const LoadInst *LI = dyn_cast<LoadInst>(Val: Op)) |
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| 40 | if (AA.pointsToConstantMemory(P: LI->getPointerOperand())) |
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| 41 | return false; |
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| 42 | |
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| 43 | // Otherwise assume the worst. |
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| 44 | return true; |
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| 45 | } |
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| 46 | |
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