1 //===- Assumptions.cpp ------ Collection of helpers for assumptions -------===// 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 // 9 // This file implements helper functions for accessing assumption infomration 10 // inside of the "llvm.assume" metadata. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "llvm/IR/Assumptions.h" 15 #include "llvm/ADT/SetOperations.h" 16 #include "llvm/ADT/StringExtras.h" 17 #include "llvm/IR/Attributes.h" 18 #include "llvm/IR/Function.h" 19 #include "llvm/IR/InstrTypes.h" 20 21 using namespace llvm; 22 23 namespace { 24 bool hasAssumption(const Attribute &A, 25 const KnownAssumptionString &AssumptionStr) { 26 if (!A.isValid()) 27 return false; 28 assert(A.isStringAttribute() && "Expected a string attribute!"); 29 30 SmallVector<StringRef, 8> Strings; 31 A.getValueAsString().split(Strings, ","); 32 33 return llvm::is_contained(Strings, AssumptionStr); 34 } 35 36 DenseSet<StringRef> getAssumptions(const Attribute &A) { 37 if (!A.isValid()) 38 return DenseSet<StringRef>(); 39 assert(A.isStringAttribute() && "Expected a string attribute!"); 40 41 DenseSet<StringRef> Assumptions; 42 SmallVector<StringRef, 8> Strings; 43 A.getValueAsString().split(Strings, ","); 44 45 for (StringRef Str : Strings) 46 Assumptions.insert(Str); 47 return Assumptions; 48 } 49 50 template <typename AttrSite> 51 bool addAssumptionsImpl(AttrSite &Site, 52 const DenseSet<StringRef> &Assumptions) { 53 if (Assumptions.empty()) 54 return false; 55 56 DenseSet<StringRef> CurAssumptions = getAssumptions(Site); 57 58 if (!set_union(CurAssumptions, Assumptions)) 59 return false; 60 61 LLVMContext &Ctx = Site.getContext(); 62 Site.addFnAttr(llvm::Attribute::get( 63 Ctx, llvm::AssumptionAttrKey, 64 llvm::join(CurAssumptions.begin(), CurAssumptions.end(), ","))); 65 66 return true; 67 } 68 } // namespace 69 70 bool llvm::hasAssumption(const Function &F, 71 const KnownAssumptionString &AssumptionStr) { 72 const Attribute &A = F.getFnAttribute(AssumptionAttrKey); 73 return ::hasAssumption(A, AssumptionStr); 74 } 75 76 bool llvm::hasAssumption(const CallBase &CB, 77 const KnownAssumptionString &AssumptionStr) { 78 if (Function *F = CB.getCalledFunction()) 79 if (hasAssumption(*F, AssumptionStr)) 80 return true; 81 82 const Attribute &A = CB.getFnAttr(AssumptionAttrKey); 83 return ::hasAssumption(A, AssumptionStr); 84 } 85 86 DenseSet<StringRef> llvm::getAssumptions(const Function &F) { 87 const Attribute &A = F.getFnAttribute(AssumptionAttrKey); 88 return ::getAssumptions(A); 89 } 90 91 DenseSet<StringRef> llvm::getAssumptions(const CallBase &CB) { 92 const Attribute &A = CB.getFnAttr(AssumptionAttrKey); 93 return ::getAssumptions(A); 94 } 95 96 bool llvm::addAssumptions(Function &F, const DenseSet<StringRef> &Assumptions) { 97 return ::addAssumptionsImpl(F, Assumptions); 98 } 99 100 bool llvm::addAssumptions(CallBase &CB, 101 const DenseSet<StringRef> &Assumptions) { 102 return ::addAssumptionsImpl(CB, Assumptions); 103 } 104 105 StringSet<> llvm::KnownAssumptionStrings({ 106 "omp_no_openmp", // OpenMP 5.1 107 "omp_no_openmp_routines", // OpenMP 5.1 108 "omp_no_parallelism", // OpenMP 5.1 109 "ompx_spmd_amenable", // OpenMPOpt extension 110 }); 111