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 for (StringRef Str : Strings)
46 Assumptions.insert(Str);
47 return Assumptions;
48 }
49
50 template <typename AttrSite>
addAssumptionsImpl(AttrSite & Site,const DenseSet<StringRef> & Assumptions)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
hasAssumption(const Function & F,const KnownAssumptionString & AssumptionStr)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
hasAssumption(const CallBase & CB,const KnownAssumptionString & AssumptionStr)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
getAssumptions(const Function & F)86 DenseSet<StringRef> llvm::getAssumptions(const Function &F) {
87 const Attribute &A = F.getFnAttribute(AssumptionAttrKey);
88 return ::getAssumptions(A);
89 }
90
getAssumptions(const CallBase & CB)91 DenseSet<StringRef> llvm::getAssumptions(const CallBase &CB) {
92 const Attribute &A = CB.getFnAttr(AssumptionAttrKey);
93 return ::getAssumptions(A);
94 }
95
addAssumptions(Function & F,const DenseSet<StringRef> & Assumptions)96 bool llvm::addAssumptions(Function &F, const DenseSet<StringRef> &Assumptions) {
97 return ::addAssumptionsImpl(F, Assumptions);
98 }
99
addAssumptions(CallBase & CB,const DenseSet<StringRef> & Assumptions)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 "ompx_no_call_asm", // OpenMPOpt extension
111 });
112