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 Assumptions.insert_range(Strings); 46 return Assumptions; 47 } 48 49 template <typename AttrSite> 50 bool addAssumptionsImpl(AttrSite &Site, 51 const DenseSet<StringRef> &Assumptions) { 52 if (Assumptions.empty()) 53 return false; 54 55 DenseSet<StringRef> CurAssumptions = getAssumptions(Site); 56 57 if (!set_union(CurAssumptions, Assumptions)) 58 return false; 59 60 LLVMContext &Ctx = Site.getContext(); 61 Site.addFnAttr(llvm::Attribute::get( 62 Ctx, llvm::AssumptionAttrKey, 63 llvm::join(CurAssumptions.begin(), CurAssumptions.end(), ","))); 64 65 return true; 66 } 67 } // namespace 68 69 bool llvm::hasAssumption(const Function &F, 70 const KnownAssumptionString &AssumptionStr) { 71 const Attribute &A = F.getFnAttribute(AssumptionAttrKey); 72 return ::hasAssumption(A, AssumptionStr); 73 } 74 75 bool llvm::hasAssumption(const CallBase &CB, 76 const KnownAssumptionString &AssumptionStr) { 77 if (Function *F = CB.getCalledFunction()) 78 if (hasAssumption(*F, AssumptionStr)) 79 return true; 80 81 const Attribute &A = CB.getFnAttr(AssumptionAttrKey); 82 return ::hasAssumption(A, AssumptionStr); 83 } 84 85 DenseSet<StringRef> llvm::getAssumptions(const Function &F) { 86 const Attribute &A = F.getFnAttribute(AssumptionAttrKey); 87 return ::getAssumptions(A); 88 } 89 90 DenseSet<StringRef> llvm::getAssumptions(const CallBase &CB) { 91 const Attribute &A = CB.getFnAttr(AssumptionAttrKey); 92 return ::getAssumptions(A); 93 } 94 95 bool llvm::addAssumptions(Function &F, const DenseSet<StringRef> &Assumptions) { 96 return ::addAssumptionsImpl(F, Assumptions); 97 } 98 99 bool llvm::addAssumptions(CallBase &CB, 100 const DenseSet<StringRef> &Assumptions) { 101 return ::addAssumptionsImpl(CB, Assumptions); 102 } 103 104 StringSet<> llvm::KnownAssumptionStrings({ 105 "omp_no_openmp", // OpenMP 5.1 106 "omp_no_openmp_routines", // OpenMP 5.1 107 "omp_no_parallelism", // OpenMP 5.1 108 "omp_no_openmp_constructs", // OpenMP 6.0 109 "ompx_spmd_amenable", // OpenMPOpt extension 110 "ompx_no_call_asm", // OpenMPOpt extension 111 "ompx_aligned_barrier", // OpenMPOpt extension 112 }); 113