1 //===-- GuardUtils.cpp - Utils for work with guards -------------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // Utils that are used to perform analyzes related to guards and their 9 // conditions. 10 //===----------------------------------------------------------------------===// 11 12 #include "llvm/Analysis/GuardUtils.h" 13 #include "llvm/IR/PatternMatch.h" 14 15 using namespace llvm; 16 17 bool llvm::isGuard(const User *U) { 18 using namespace llvm::PatternMatch; 19 return match(U, m_Intrinsic<Intrinsic::experimental_guard>()); 20 } 21 22 bool llvm::isGuardAsWidenableBranch(const User *U) { 23 Value *Condition, *WidenableCondition; 24 BasicBlock *GuardedBB, *DeoptBB; 25 if (!parseWidenableBranch(U, Condition, WidenableCondition, GuardedBB, 26 DeoptBB)) 27 return false; 28 using namespace llvm::PatternMatch; 29 for (auto &Insn : *DeoptBB) { 30 if (match(&Insn, m_Intrinsic<Intrinsic::experimental_deoptimize>())) 31 return true; 32 if (Insn.mayHaveSideEffects()) 33 return false; 34 } 35 return false; 36 } 37 38 bool llvm::parseWidenableBranch(const User *U, Value *&Condition, 39 Value *&WidenableCondition, 40 BasicBlock *&IfTrueBB, BasicBlock *&IfFalseBB) { 41 using namespace llvm::PatternMatch; 42 if (!match(U, m_Br(m_And(m_Value(Condition), m_Value(WidenableCondition)), 43 IfTrueBB, IfFalseBB))) 44 return false; 45 // TODO: At the moment, we only recognize the branch if the WC call in this 46 // specific position. We should generalize! 47 return match(WidenableCondition, 48 m_Intrinsic<Intrinsic::experimental_widenable_condition>()); 49 } 50