1 //===- EHPersonalities.h - Compute EH-related information -----------------===//
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 #ifndef LLVM_IR_EHPERSONALITIES_H
10 #define LLVM_IR_EHPERSONALITIES_H
11
12 #include "llvm/ADT/DenseMap.h"
13 #include "llvm/ADT/TinyPtrVector.h"
14
15 namespace llvm {
16 class BasicBlock;
17 class Function;
18 class Triple;
19 class Value;
20
21 enum class EHPersonality {
22 Unknown,
23 GNU_Ada,
24 GNU_C,
25 GNU_C_SjLj,
26 GNU_CXX,
27 GNU_CXX_SjLj,
28 GNU_ObjC,
29 MSVC_X86SEH,
30 MSVC_TableSEH,
31 MSVC_CXX,
32 CoreCLR,
33 Rust,
34 Wasm_CXX,
35 XL_CXX,
36 ZOS_CXX,
37 };
38
39 /// See if the given exception handling personality function is one
40 /// that we understand. If so, return a description of it; otherwise return
41 /// Unknown.
42 EHPersonality classifyEHPersonality(const Value *Pers);
43
44 StringRef getEHPersonalityName(EHPersonality Pers);
45
46 EHPersonality getDefaultEHPersonality(const Triple &T);
47
48 /// Returns true if this personality function catches asynchronous
49 /// exceptions.
isAsynchronousEHPersonality(EHPersonality Pers)50 inline bool isAsynchronousEHPersonality(EHPersonality Pers) {
51 // The two SEH personality functions can catch asynch exceptions. We assume
52 // unknown personalities don't catch asynch exceptions.
53 switch (Pers) {
54 case EHPersonality::MSVC_X86SEH:
55 case EHPersonality::MSVC_TableSEH:
56 return true;
57 default:
58 return false;
59 }
60 llvm_unreachable("invalid enum");
61 }
62
63 /// Returns true if this is a personality function that invokes
64 /// handler funclets (which must return to it).
isFuncletEHPersonality(EHPersonality Pers)65 inline bool isFuncletEHPersonality(EHPersonality Pers) {
66 switch (Pers) {
67 case EHPersonality::MSVC_CXX:
68 case EHPersonality::MSVC_X86SEH:
69 case EHPersonality::MSVC_TableSEH:
70 case EHPersonality::CoreCLR:
71 return true;
72 default:
73 return false;
74 }
75 llvm_unreachable("invalid enum");
76 }
77
78 /// Returns true if this personality uses scope-style EH IR instructions:
79 /// catchswitch, catchpad/ret, and cleanuppad/ret.
isScopedEHPersonality(EHPersonality Pers)80 inline bool isScopedEHPersonality(EHPersonality Pers) {
81 switch (Pers) {
82 case EHPersonality::MSVC_CXX:
83 case EHPersonality::MSVC_X86SEH:
84 case EHPersonality::MSVC_TableSEH:
85 case EHPersonality::CoreCLR:
86 case EHPersonality::Wasm_CXX:
87 return true;
88 default:
89 return false;
90 }
91 llvm_unreachable("invalid enum");
92 }
93
94 /// Return true if this personality may be safely removed if there
95 /// are no invoke instructions remaining in the current function.
isNoOpWithoutInvoke(EHPersonality Pers)96 inline bool isNoOpWithoutInvoke(EHPersonality Pers) {
97 switch (Pers) {
98 case EHPersonality::Unknown:
99 return false;
100 // All known personalities currently have this behavior
101 default:
102 return true;
103 }
104 llvm_unreachable("invalid enum");
105 }
106
107 bool canSimplifyInvokeNoUnwind(const Function *F);
108
109 typedef TinyPtrVector<BasicBlock *> ColorVector;
110
111 /// If an EH funclet personality is in use (see isFuncletEHPersonality),
112 /// this will recompute which blocks are in which funclet. It is possible that
113 /// some blocks are in multiple funclets. Consider this analysis to be
114 /// expensive.
115 DenseMap<BasicBlock *, ColorVector> colorEHFunclets(Function &F);
116
117 } // end namespace llvm
118
119 #endif // LLVM_IR_EHPERSONALITIES_H
120