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 {
hasAssumption(const Attribute & A,const KnownAssumptionString & AssumptionStr)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
getAssumptions(const Attribute & A)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>
addAssumptionsImpl(AttrSite & Site,const DenseSet<StringRef> & Assumptions)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
hasAssumption(const Function & F,const KnownAssumptionString & AssumptionStr)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
hasAssumption(const CallBase & CB,const KnownAssumptionString & AssumptionStr)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
getAssumptions(const Function & F)85 DenseSet<StringRef> llvm::getAssumptions(const Function &F) {
86 const Attribute &A = F.getFnAttribute(AssumptionAttrKey);
87 return ::getAssumptions(A);
88 }
89
getAssumptions(const CallBase & CB)90 DenseSet<StringRef> llvm::getAssumptions(const CallBase &CB) {
91 const Attribute &A = CB.getFnAttr(AssumptionAttrKey);
92 return ::getAssumptions(A);
93 }
94
addAssumptions(Function & F,const DenseSet<StringRef> & Assumptions)95 bool llvm::addAssumptions(Function &F, const DenseSet<StringRef> &Assumptions) {
96 return ::addAssumptionsImpl(F, Assumptions);
97 }
98
addAssumptions(CallBase & CB,const DenseSet<StringRef> & Assumptions)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