File: | include/llvm/Support/Error.h |
Warning: | line 201, column 5 Potential leak of memory pointed to by 'Payload._M_t._M_head_impl' |
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1 | #include "llvm/ADT/DenseMap.h" | |||
2 | #include "llvm/ADT/StringExtras.h" | |||
3 | #include "llvm/ADT/StringSet.h" | |||
4 | #include "llvm/DebugInfo/DIContext.h" | |||
5 | #include "llvm/DebugInfo/DWARF/DWARFContext.h" | |||
6 | #include "llvm/DebugInfo/DWARF/DWARFDebugLoc.h" | |||
7 | #include "llvm/Object/ObjectFile.h" | |||
8 | ||||
9 | #define DEBUG_TYPE"dwarfdump" "dwarfdump" | |||
10 | using namespace llvm; | |||
11 | using namespace object; | |||
12 | ||||
13 | /// Holds statistics for one function (or other entity that has a PC range and | |||
14 | /// contains variables, such as a compile unit). | |||
15 | struct PerFunctionStats { | |||
16 | /// Number of inlined instances of this function. | |||
17 | unsigned NumFnInlined = 0; | |||
18 | /// Number of variables with location across all inlined instances. | |||
19 | unsigned TotalVarWithLoc = 0; | |||
20 | /// Number of constants with location across all inlined instances. | |||
21 | unsigned ConstantMembers = 0; | |||
22 | /// List of all Variables in this function. | |||
23 | StringSet<> VarsInFunction; | |||
24 | /// Compile units also cover a PC range, but have this flag set to false. | |||
25 | bool IsFunction = false; | |||
26 | }; | |||
27 | ||||
28 | /// Holds accumulated global statistics about local variables. | |||
29 | struct GlobalStats { | |||
30 | /// Total number of PC range bytes covered by DW_AT_locations. | |||
31 | unsigned ScopeBytesCovered = 0; | |||
32 | /// Total number of PC range bytes in each variable's enclosing scope, | |||
33 | /// starting from the first definition of the variable. | |||
34 | unsigned ScopeBytesFromFirstDefinition = 0; | |||
35 | /// Total number of call site entries (DW_TAG_call_site). | |||
36 | unsigned CallSiteEntries = 0; | |||
37 | }; | |||
38 | ||||
39 | /// Extract the low pc from a Die. | |||
40 | static uint64_t getLowPC(DWARFDie Die) { | |||
41 | auto RangesOrError = Die.getAddressRanges(); | |||
42 | DWARFAddressRangesVector Ranges; | |||
43 | if (RangesOrError) | |||
44 | Ranges = RangesOrError.get(); | |||
45 | else | |||
46 | llvm::consumeError(RangesOrError.takeError()); | |||
47 | if (Ranges.size()) | |||
48 | return Ranges[0].LowPC; | |||
49 | return dwarf::toAddress(Die.find(dwarf::DW_AT_low_pc), 0); | |||
50 | } | |||
51 | ||||
52 | /// Collect debug info quality metrics for one DIE. | |||
53 | static void collectStatsForDie(DWARFDie Die, std::string FnPrefix, | |||
54 | std::string VarPrefix, uint64_t ScopeLowPC, | |||
55 | uint64_t BytesInScope, | |||
56 | StringMap<PerFunctionStats> &FnStatMap, | |||
57 | GlobalStats &GlobalStats) { | |||
58 | bool HasLoc = false; | |||
59 | uint64_t BytesCovered = 0; | |||
60 | uint64_t OffsetToFirstDefinition = 0; | |||
61 | ||||
62 | if (Die.getTag() == dwarf::DW_TAG_call_site) { | |||
63 | GlobalStats.CallSiteEntries++; | |||
64 | return; | |||
65 | } | |||
66 | ||||
67 | if (Die.getTag() != dwarf::DW_TAG_formal_parameter && | |||
68 | Die.getTag() != dwarf::DW_TAG_variable && | |||
69 | Die.getTag() != dwarf::DW_TAG_member) { | |||
70 | // Not a variable or constant member. | |||
71 | return; | |||
72 | } | |||
73 | ||||
74 | if (Die.find(dwarf::DW_AT_const_value)) { | |||
75 | // This catches constant members *and* variables. | |||
76 | HasLoc = true; | |||
77 | BytesCovered = BytesInScope; | |||
78 | } else { | |||
79 | if (Die.getTag() == dwarf::DW_TAG_member) { | |||
80 | // Non-const member. | |||
81 | return; | |||
82 | } | |||
83 | // Handle variables and function arguments. | |||
84 | auto FormValue = Die.find(dwarf::DW_AT_location); | |||
85 | HasLoc = FormValue.hasValue(); | |||
86 | if (HasLoc) { | |||
87 | // Get PC coverage. | |||
88 | if (auto DebugLocOffset = FormValue->getAsSectionOffset()) { | |||
89 | auto *DebugLoc = Die.getDwarfUnit()->getContext().getDebugLoc(); | |||
90 | if (auto List = DebugLoc->getLocationListAtOffset(*DebugLocOffset)) { | |||
91 | for (auto Entry : List->Entries) | |||
92 | BytesCovered += Entry.End - Entry.Begin; | |||
93 | if (List->Entries.size()) { | |||
94 | uint64_t FirstDef = List->Entries[0].Begin; | |||
95 | uint64_t UnitOfs = getLowPC(Die.getDwarfUnit()->getUnitDIE()); | |||
96 | // Ranges sometimes start before the lexical scope. | |||
97 | if (UnitOfs + FirstDef >= ScopeLowPC) | |||
98 | OffsetToFirstDefinition = UnitOfs + FirstDef - ScopeLowPC; | |||
99 | // Or even after it. Count that as a failure. | |||
100 | if (OffsetToFirstDefinition > BytesInScope) | |||
101 | OffsetToFirstDefinition = 0; | |||
102 | } | |||
103 | } | |||
104 | assert(BytesInScope)((BytesInScope) ? static_cast<void> (0) : __assert_fail ("BytesInScope", "/build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-dwarfdump/Statistics.cpp" , 104, __PRETTY_FUNCTION__)); | |||
105 | } else { | |||
106 | // Assume the entire range is covered by a single location. | |||
107 | BytesCovered = BytesInScope; | |||
108 | } | |||
109 | } | |||
110 | } | |||
111 | ||||
112 | // Collect PC range coverage data. | |||
113 | auto &FnStats = FnStatMap[FnPrefix]; | |||
114 | if (DWARFDie D = | |||
115 | Die.getAttributeValueAsReferencedDie(dwarf::DW_AT_abstract_origin)) | |||
116 | Die = D; | |||
117 | // By using the variable name + the path through the lexical block tree, the | |||
118 | // keys are consistent across duplicate abstract origins in different CUs. | |||
119 | std::string VarName = StringRef(Die.getName(DINameKind::ShortName)); | |||
120 | FnStats.VarsInFunction.insert(VarPrefix+VarName); | |||
121 | if (BytesInScope) { | |||
122 | FnStats.TotalVarWithLoc += (unsigned)HasLoc; | |||
123 | // Adjust for the fact the variables often start their lifetime in the | |||
124 | // middle of the scope. | |||
125 | BytesInScope -= OffsetToFirstDefinition; | |||
126 | // Turns out we have a lot of ranges that extend past the lexical scope. | |||
127 | GlobalStats.ScopeBytesCovered += std::min(BytesInScope, BytesCovered); | |||
128 | GlobalStats.ScopeBytesFromFirstDefinition += BytesInScope; | |||
129 | assert(GlobalStats.ScopeBytesCovered <=((GlobalStats.ScopeBytesCovered <= GlobalStats.ScopeBytesFromFirstDefinition ) ? static_cast<void> (0) : __assert_fail ("GlobalStats.ScopeBytesCovered <= GlobalStats.ScopeBytesFromFirstDefinition" , "/build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-dwarfdump/Statistics.cpp" , 130, __PRETTY_FUNCTION__)) | |||
130 | GlobalStats.ScopeBytesFromFirstDefinition)((GlobalStats.ScopeBytesCovered <= GlobalStats.ScopeBytesFromFirstDefinition ) ? static_cast<void> (0) : __assert_fail ("GlobalStats.ScopeBytesCovered <= GlobalStats.ScopeBytesFromFirstDefinition" , "/build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-dwarfdump/Statistics.cpp" , 130, __PRETTY_FUNCTION__)); | |||
131 | } else { | |||
132 | FnStats.ConstantMembers++; | |||
133 | } | |||
134 | } | |||
135 | ||||
136 | /// Recursively collect debug info quality metrics. | |||
137 | static void collectStatsRecursive(DWARFDie Die, std::string FnPrefix, | |||
138 | std::string VarPrefix, uint64_t ScopeLowPC, | |||
139 | uint64_t BytesInScope, | |||
140 | StringMap<PerFunctionStats> &FnStatMap, | |||
141 | GlobalStats &GlobalStats) { | |||
142 | // Handle any kind of lexical scope. | |||
143 | if (Die.getTag() == dwarf::DW_TAG_subprogram || | |||
144 | Die.getTag() == dwarf::DW_TAG_inlined_subroutine || | |||
145 | Die.getTag() == dwarf::DW_TAG_lexical_block) { | |||
146 | ||||
147 | // Reset VarPrefix when entering a new function. | |||
148 | if (Die.getTag() == dwarf::DW_TAG_subprogram || | |||
149 | Die.getTag() == dwarf::DW_TAG_inlined_subroutine) | |||
150 | VarPrefix = "v"; | |||
151 | ||||
152 | // Ignore forward declarations. | |||
153 | if (Die.find(dwarf::DW_AT_declaration)) | |||
154 | return; | |||
155 | ||||
156 | // Count the function. | |||
157 | if (Die.getTag() != dwarf::DW_TAG_lexical_block) { | |||
158 | StringRef Name = Die.getName(DINameKind::LinkageName); | |||
159 | if (Name.empty()) | |||
160 | Name = Die.getName(DINameKind::ShortName); | |||
161 | FnPrefix = Name; | |||
162 | // Skip over abstract origins. | |||
163 | if (Die.find(dwarf::DW_AT_inline)) | |||
164 | return; | |||
165 | // We've seen an (inlined) instance of this function. | |||
166 | auto &FnStats = FnStatMap[Name]; | |||
167 | FnStats.NumFnInlined++; | |||
168 | FnStats.IsFunction = true; | |||
169 | } | |||
170 | ||||
171 | // PC Ranges. | |||
172 | auto RangesOrError = Die.getAddressRanges(); | |||
173 | if (!RangesOrError) { | |||
174 | llvm::consumeError(RangesOrError.takeError()); | |||
175 | return; | |||
176 | } | |||
177 | ||||
178 | auto Ranges = RangesOrError.get(); | |||
179 | uint64_t BytesInThisScope = 0; | |||
180 | for (auto Range : Ranges) | |||
181 | BytesInThisScope += Range.HighPC - Range.LowPC; | |||
182 | ScopeLowPC = getLowPC(Die); | |||
183 | ||||
184 | if (BytesInThisScope) | |||
185 | BytesInScope = BytesInThisScope; | |||
186 | } else { | |||
187 | // Not a scope, visit the Die itself. It could be a variable. | |||
188 | collectStatsForDie(Die, FnPrefix, VarPrefix, ScopeLowPC, BytesInScope, | |||
189 | FnStatMap, GlobalStats); | |||
190 | } | |||
191 | ||||
192 | // Traverse children. | |||
193 | unsigned LexicalBlockIndex = 0; | |||
194 | DWARFDie Child = Die.getFirstChild(); | |||
195 | while (Child) { | |||
196 | std::string ChildVarPrefix = VarPrefix; | |||
197 | if (Child.getTag() == dwarf::DW_TAG_lexical_block) | |||
198 | ChildVarPrefix += toHex(LexicalBlockIndex++) + '.'; | |||
199 | ||||
200 | collectStatsRecursive(Child, FnPrefix, ChildVarPrefix, ScopeLowPC, | |||
201 | BytesInScope, FnStatMap, GlobalStats); | |||
202 | Child = Child.getSibling(); | |||
203 | } | |||
204 | } | |||
205 | ||||
206 | /// Print machine-readable output. | |||
207 | /// The machine-readable format is single-line JSON output. | |||
208 | /// \{ | |||
209 | static void printDatum(raw_ostream &OS, const char *Key, StringRef Value) { | |||
210 | OS << ",\"" << Key << "\":\"" << Value << '"'; | |||
211 | LLVM_DEBUG(llvm::dbgs() << Key << ": " << Value << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("dwarfdump")) { llvm::dbgs() << Key << ": " << Value << '\n'; } } while (false); | |||
212 | } | |||
213 | static void printDatum(raw_ostream &OS, const char *Key, uint64_t Value) { | |||
214 | OS << ",\"" << Key << "\":" << Value; | |||
215 | LLVM_DEBUG(llvm::dbgs() << Key << ": " << Value << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("dwarfdump")) { llvm::dbgs() << Key << ": " << Value << '\n'; } } while (false); | |||
216 | } | |||
217 | /// \} | |||
218 | ||||
219 | /// Collect debug info quality metrics for an entire DIContext. | |||
220 | /// | |||
221 | /// Do the impossible and reduce the quality of the debug info down to a few | |||
222 | /// numbers. The idea is to condense the data into numbers that can be tracked | |||
223 | /// over time to identify trends in newer compiler versions and gauge the effect | |||
224 | /// of particular optimizations. The raw numbers themselves are not particularly | |||
225 | /// useful, only the delta between compiling the same program with different | |||
226 | /// compilers is. | |||
227 | bool collectStatsForObjectFile(ObjectFile &Obj, DWARFContext &DICtx, | |||
228 | Twine Filename, raw_ostream &OS) { | |||
229 | StringRef FormatName = Obj.getFileFormatName(); | |||
230 | GlobalStats GlobalStats; | |||
231 | StringMap<PerFunctionStats> Statistics; | |||
232 | for (const auto &CU : static_cast<DWARFContext *>(&DICtx)->compile_units()) | |||
| ||||
233 | if (DWARFDie CUDie = CU->getUnitDIE(false)) | |||
234 | collectStatsRecursive(CUDie, "/", "g", 0, 0, Statistics, GlobalStats); | |||
235 | ||||
236 | /// The version number should be increased every time the algorithm is changed | |||
237 | /// (including bug fixes). New metrics may be added without increasing the | |||
238 | /// version. | |||
239 | unsigned Version = 1; | |||
240 | unsigned VarTotal = 0; | |||
241 | unsigned VarUnique = 0; | |||
242 | unsigned VarWithLoc = 0; | |||
243 | unsigned NumFunctions = 0; | |||
244 | unsigned NumInlinedFunctions = 0; | |||
245 | for (auto &Entry : Statistics) { | |||
246 | PerFunctionStats &Stats = Entry.getValue(); | |||
247 | unsigned TotalVars = Stats.VarsInFunction.size() * Stats.NumFnInlined; | |||
248 | unsigned Constants = Stats.ConstantMembers; | |||
249 | VarWithLoc += Stats.TotalVarWithLoc + Constants; | |||
250 | VarTotal += TotalVars + Constants; | |||
251 | VarUnique += Stats.VarsInFunction.size(); | |||
252 | LLVM_DEBUG(for (auto &V : Stats.VarsInFunction) llvm::dbgs()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("dwarfdump")) { for (auto &V : Stats.VarsInFunction) llvm ::dbgs() << Entry.getKey() << ": " << V.getKey () << "\n"; } } while (false) | |||
253 | << Entry.getKey() << ": " << V.getKey() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("dwarfdump")) { for (auto &V : Stats.VarsInFunction) llvm ::dbgs() << Entry.getKey() << ": " << V.getKey () << "\n"; } } while (false); | |||
254 | NumFunctions += Stats.IsFunction; | |||
255 | NumInlinedFunctions += Stats.IsFunction * Stats.NumFnInlined; | |||
256 | } | |||
257 | ||||
258 | // Print summary. | |||
259 | OS.SetBufferSize(1024); | |||
260 | OS << "{\"version\":" << Version; | |||
261 | LLVM_DEBUG(llvm::dbgs() << "Variable location quality metrics\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("dwarfdump")) { llvm::dbgs() << "Variable location quality metrics\n" ; llvm::dbgs() << "---------------------------------\n" ; } } while (false) | |||
262 | llvm::dbgs() << "---------------------------------\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("dwarfdump")) { llvm::dbgs() << "Variable location quality metrics\n" ; llvm::dbgs() << "---------------------------------\n" ; } } while (false); | |||
263 | printDatum(OS, "file", Filename.str()); | |||
264 | printDatum(OS, "format", FormatName); | |||
265 | printDatum(OS, "source functions", NumFunctions); | |||
266 | printDatum(OS, "inlined functions", NumInlinedFunctions); | |||
267 | printDatum(OS, "unique source variables", VarUnique); | |||
268 | printDatum(OS, "source variables", VarTotal); | |||
269 | printDatum(OS, "variables with location", VarWithLoc); | |||
270 | printDatum(OS, "call site entries", GlobalStats.CallSiteEntries); | |||
271 | printDatum(OS, "scope bytes total", | |||
272 | GlobalStats.ScopeBytesFromFirstDefinition); | |||
273 | printDatum(OS, "scope bytes covered", GlobalStats.ScopeBytesCovered); | |||
274 | OS << "}\n"; | |||
275 | LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("dwarfdump")) { llvm::dbgs() << "Total Availability: " << (int)std::round((VarWithLoc * 100.0) / VarTotal) << "%\n"; llvm::dbgs() << "PC Ranges covered: " << ( int)std::round((GlobalStats.ScopeBytesCovered * 100.0) / GlobalStats .ScopeBytesFromFirstDefinition) << "%\n"; } } while (false ) | |||
276 | llvm::dbgs() << "Total Availability: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("dwarfdump")) { llvm::dbgs() << "Total Availability: " << (int)std::round((VarWithLoc * 100.0) / VarTotal) << "%\n"; llvm::dbgs() << "PC Ranges covered: " << ( int)std::round((GlobalStats.ScopeBytesCovered * 100.0) / GlobalStats .ScopeBytesFromFirstDefinition) << "%\n"; } } while (false ) | |||
277 | << (int)std::round((VarWithLoc * 100.0) / VarTotal) << "%\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("dwarfdump")) { llvm::dbgs() << "Total Availability: " << (int)std::round((VarWithLoc * 100.0) / VarTotal) << "%\n"; llvm::dbgs() << "PC Ranges covered: " << ( int)std::round((GlobalStats.ScopeBytesCovered * 100.0) / GlobalStats .ScopeBytesFromFirstDefinition) << "%\n"; } } while (false ) | |||
278 | llvm::dbgs() << "PC Ranges covered: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("dwarfdump")) { llvm::dbgs() << "Total Availability: " << (int)std::round((VarWithLoc * 100.0) / VarTotal) << "%\n"; llvm::dbgs() << "PC Ranges covered: " << ( int)std::round((GlobalStats.ScopeBytesCovered * 100.0) / GlobalStats .ScopeBytesFromFirstDefinition) << "%\n"; } } while (false ) | |||
279 | << (int)std::round((GlobalStats.ScopeBytesCovered * 100.0) /do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("dwarfdump")) { llvm::dbgs() << "Total Availability: " << (int)std::round((VarWithLoc * 100.0) / VarTotal) << "%\n"; llvm::dbgs() << "PC Ranges covered: " << ( int)std::round((GlobalStats.ScopeBytesCovered * 100.0) / GlobalStats .ScopeBytesFromFirstDefinition) << "%\n"; } } while (false ) | |||
280 | GlobalStats.ScopeBytesFromFirstDefinition)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("dwarfdump")) { llvm::dbgs() << "Total Availability: " << (int)std::round((VarWithLoc * 100.0) / VarTotal) << "%\n"; llvm::dbgs() << "PC Ranges covered: " << ( int)std::round((GlobalStats.ScopeBytesCovered * 100.0) / GlobalStats .ScopeBytesFromFirstDefinition) << "%\n"; } } while (false ) | |||
281 | << "%\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("dwarfdump")) { llvm::dbgs() << "Total Availability: " << (int)std::round((VarWithLoc * 100.0) / VarTotal) << "%\n"; llvm::dbgs() << "PC Ranges covered: " << ( int)std::round((GlobalStats.ScopeBytesCovered * 100.0) / GlobalStats .ScopeBytesFromFirstDefinition) << "%\n"; } } while (false ); | |||
282 | return true; | |||
283 | } |
1 | //===- llvm/Support/Error.h - Recoverable error handling --------*- C++ -*-===// | |||
2 | // | |||
3 | // The LLVM Compiler Infrastructure | |||
4 | // | |||
5 | // This file is distributed under the University of Illinois Open Source | |||
6 | // License. See LICENSE.TXT for details. | |||
7 | // | |||
8 | //===----------------------------------------------------------------------===// | |||
9 | // | |||
10 | // This file defines an API used to report recoverable errors. | |||
11 | // | |||
12 | //===----------------------------------------------------------------------===// | |||
13 | ||||
14 | #ifndef LLVM_SUPPORT_ERROR_H | |||
15 | #define LLVM_SUPPORT_ERROR_H | |||
16 | ||||
17 | #include "llvm-c/Error.h" | |||
18 | #include "llvm/ADT/STLExtras.h" | |||
19 | #include "llvm/ADT/SmallVector.h" | |||
20 | #include "llvm/ADT/StringExtras.h" | |||
21 | #include "llvm/ADT/Twine.h" | |||
22 | #include "llvm/Config/abi-breaking.h" | |||
23 | #include "llvm/Support/AlignOf.h" | |||
24 | #include "llvm/Support/Compiler.h" | |||
25 | #include "llvm/Support/Debug.h" | |||
26 | #include "llvm/Support/ErrorHandling.h" | |||
27 | #include "llvm/Support/ErrorOr.h" | |||
28 | #include "llvm/Support/Format.h" | |||
29 | #include "llvm/Support/raw_ostream.h" | |||
30 | #include <algorithm> | |||
31 | #include <cassert> | |||
32 | #include <cstdint> | |||
33 | #include <cstdlib> | |||
34 | #include <functional> | |||
35 | #include <memory> | |||
36 | #include <new> | |||
37 | #include <string> | |||
38 | #include <system_error> | |||
39 | #include <type_traits> | |||
40 | #include <utility> | |||
41 | #include <vector> | |||
42 | ||||
43 | namespace llvm { | |||
44 | ||||
45 | class ErrorSuccess; | |||
46 | ||||
47 | /// Base class for error info classes. Do not extend this directly: Extend | |||
48 | /// the ErrorInfo template subclass instead. | |||
49 | class ErrorInfoBase { | |||
50 | public: | |||
51 | virtual ~ErrorInfoBase() = default; | |||
52 | ||||
53 | /// Print an error message to an output stream. | |||
54 | virtual void log(raw_ostream &OS) const = 0; | |||
55 | ||||
56 | /// Return the error message as a string. | |||
57 | virtual std::string message() const { | |||
58 | std::string Msg; | |||
59 | raw_string_ostream OS(Msg); | |||
60 | log(OS); | |||
61 | return OS.str(); | |||
62 | } | |||
63 | ||||
64 | /// Convert this error to a std::error_code. | |||
65 | /// | |||
66 | /// This is a temporary crutch to enable interaction with code still | |||
67 | /// using std::error_code. It will be removed in the future. | |||
68 | virtual std::error_code convertToErrorCode() const = 0; | |||
69 | ||||
70 | // Returns the class ID for this type. | |||
71 | static const void *classID() { return &ID; } | |||
72 | ||||
73 | // Returns the class ID for the dynamic type of this ErrorInfoBase instance. | |||
74 | virtual const void *dynamicClassID() const = 0; | |||
75 | ||||
76 | // Check whether this instance is a subclass of the class identified by | |||
77 | // ClassID. | |||
78 | virtual bool isA(const void *const ClassID) const { | |||
79 | return ClassID == classID(); | |||
80 | } | |||
81 | ||||
82 | // Check whether this instance is a subclass of ErrorInfoT. | |||
83 | template <typename ErrorInfoT> bool isA() const { | |||
84 | return isA(ErrorInfoT::classID()); | |||
85 | } | |||
86 | ||||
87 | private: | |||
88 | virtual void anchor(); | |||
89 | ||||
90 | static char ID; | |||
91 | }; | |||
92 | ||||
93 | /// Lightweight error class with error context and mandatory checking. | |||
94 | /// | |||
95 | /// Instances of this class wrap a ErrorInfoBase pointer. Failure states | |||
96 | /// are represented by setting the pointer to a ErrorInfoBase subclass | |||
97 | /// instance containing information describing the failure. Success is | |||
98 | /// represented by a null pointer value. | |||
99 | /// | |||
100 | /// Instances of Error also contains a 'Checked' flag, which must be set | |||
101 | /// before the destructor is called, otherwise the destructor will trigger a | |||
102 | /// runtime error. This enforces at runtime the requirement that all Error | |||
103 | /// instances be checked or returned to the caller. | |||
104 | /// | |||
105 | /// There are two ways to set the checked flag, depending on what state the | |||
106 | /// Error instance is in. For Error instances indicating success, it | |||
107 | /// is sufficient to invoke the boolean conversion operator. E.g.: | |||
108 | /// | |||
109 | /// @code{.cpp} | |||
110 | /// Error foo(<...>); | |||
111 | /// | |||
112 | /// if (auto E = foo(<...>)) | |||
113 | /// return E; // <- Return E if it is in the error state. | |||
114 | /// // We have verified that E was in the success state. It can now be safely | |||
115 | /// // destroyed. | |||
116 | /// @endcode | |||
117 | /// | |||
118 | /// A success value *can not* be dropped. For example, just calling 'foo(<...>)' | |||
119 | /// without testing the return value will raise a runtime error, even if foo | |||
120 | /// returns success. | |||
121 | /// | |||
122 | /// For Error instances representing failure, you must use either the | |||
123 | /// handleErrors or handleAllErrors function with a typed handler. E.g.: | |||
124 | /// | |||
125 | /// @code{.cpp} | |||
126 | /// class MyErrorInfo : public ErrorInfo<MyErrorInfo> { | |||
127 | /// // Custom error info. | |||
128 | /// }; | |||
129 | /// | |||
130 | /// Error foo(<...>) { return make_error<MyErrorInfo>(...); } | |||
131 | /// | |||
132 | /// auto E = foo(<...>); // <- foo returns failure with MyErrorInfo. | |||
133 | /// auto NewE = | |||
134 | /// handleErrors(E, | |||
135 | /// [](const MyErrorInfo &M) { | |||
136 | /// // Deal with the error. | |||
137 | /// }, | |||
138 | /// [](std::unique_ptr<OtherError> M) -> Error { | |||
139 | /// if (canHandle(*M)) { | |||
140 | /// // handle error. | |||
141 | /// return Error::success(); | |||
142 | /// } | |||
143 | /// // Couldn't handle this error instance. Pass it up the stack. | |||
144 | /// return Error(std::move(M)); | |||
145 | /// ); | |||
146 | /// // Note - we must check or return NewE in case any of the handlers | |||
147 | /// // returned a new error. | |||
148 | /// @endcode | |||
149 | /// | |||
150 | /// The handleAllErrors function is identical to handleErrors, except | |||
151 | /// that it has a void return type, and requires all errors to be handled and | |||
152 | /// no new errors be returned. It prevents errors (assuming they can all be | |||
153 | /// handled) from having to be bubbled all the way to the top-level. | |||
154 | /// | |||
155 | /// *All* Error instances must be checked before destruction, even if | |||
156 | /// they're moved-assigned or constructed from Success values that have already | |||
157 | /// been checked. This enforces checking through all levels of the call stack. | |||
158 | class LLVM_NODISCARD[[clang::warn_unused_result]] Error { | |||
159 | // Both ErrorList and FileError need to be able to yank ErrorInfoBase | |||
160 | // pointers out of this class to add to the error list. | |||
161 | friend class ErrorList; | |||
162 | friend class FileError; | |||
163 | ||||
164 | // handleErrors needs to be able to set the Checked flag. | |||
165 | template <typename... HandlerTs> | |||
166 | friend Error handleErrors(Error E, HandlerTs &&... Handlers); | |||
167 | ||||
168 | // Expected<T> needs to be able to steal the payload when constructed from an | |||
169 | // error. | |||
170 | template <typename T> friend class Expected; | |||
171 | ||||
172 | // wrap needs to be able to steal the payload. | |||
173 | friend LLVMErrorRef wrap(Error); | |||
174 | ||||
175 | protected: | |||
176 | /// Create a success value. Prefer using 'Error::success()' for readability | |||
177 | Error() { | |||
178 | setPtr(nullptr); | |||
179 | setChecked(false); | |||
180 | } | |||
181 | ||||
182 | public: | |||
183 | /// Create a success value. | |||
184 | static ErrorSuccess success(); | |||
185 | ||||
186 | // Errors are not copy-constructable. | |||
187 | Error(const Error &Other) = delete; | |||
188 | ||||
189 | /// Move-construct an error value. The newly constructed error is considered | |||
190 | /// unchecked, even if the source error had been checked. The original error | |||
191 | /// becomes a checked Success value, regardless of its original state. | |||
192 | Error(Error &&Other) { | |||
193 | setChecked(true); | |||
194 | *this = std::move(Other); | |||
195 | } | |||
196 | ||||
197 | /// Create an error value. Prefer using the 'make_error' function, but | |||
198 | /// this constructor can be useful when "re-throwing" errors from handlers. | |||
199 | Error(std::unique_ptr<ErrorInfoBase> Payload) { | |||
200 | setPtr(Payload.release()); | |||
201 | setChecked(false); | |||
| ||||
202 | } | |||
203 | ||||
204 | // Errors are not copy-assignable. | |||
205 | Error &operator=(const Error &Other) = delete; | |||
206 | ||||
207 | /// Move-assign an error value. The current error must represent success, you | |||
208 | /// you cannot overwrite an unhandled error. The current error is then | |||
209 | /// considered unchecked. The source error becomes a checked success value, | |||
210 | /// regardless of its original state. | |||
211 | Error &operator=(Error &&Other) { | |||
212 | // Don't allow overwriting of unchecked values. | |||
213 | assertIsChecked(); | |||
214 | setPtr(Other.getPtr()); | |||
215 | ||||
216 | // This Error is unchecked, even if the source error was checked. | |||
217 | setChecked(false); | |||
218 | ||||
219 | // Null out Other's payload and set its checked bit. | |||
220 | Other.setPtr(nullptr); | |||
221 | Other.setChecked(true); | |||
222 | ||||
223 | return *this; | |||
224 | } | |||
225 | ||||
226 | /// Destroy a Error. Fails with a call to abort() if the error is | |||
227 | /// unchecked. | |||
228 | ~Error() { | |||
229 | assertIsChecked(); | |||
230 | delete getPtr(); | |||
231 | } | |||
232 | ||||
233 | /// Bool conversion. Returns true if this Error is in a failure state, | |||
234 | /// and false if it is in an accept state. If the error is in a Success state | |||
235 | /// it will be considered checked. | |||
236 | explicit operator bool() { | |||
237 | setChecked(getPtr() == nullptr); | |||
238 | return getPtr() != nullptr; | |||
239 | } | |||
240 | ||||
241 | /// Check whether one error is a subclass of another. | |||
242 | template <typename ErrT> bool isA() const { | |||
243 | return getPtr() && getPtr()->isA(ErrT::classID()); | |||
244 | } | |||
245 | ||||
246 | /// Returns the dynamic class id of this error, or null if this is a success | |||
247 | /// value. | |||
248 | const void* dynamicClassID() const { | |||
249 | if (!getPtr()) | |||
250 | return nullptr; | |||
251 | return getPtr()->dynamicClassID(); | |||
252 | } | |||
253 | ||||
254 | private: | |||
255 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 | |||
256 | // assertIsChecked() happens very frequently, but under normal circumstances | |||
257 | // is supposed to be a no-op. So we want it to be inlined, but having a bunch | |||
258 | // of debug prints can cause the function to be too large for inlining. So | |||
259 | // it's important that we define this function out of line so that it can't be | |||
260 | // inlined. | |||
261 | LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn)) | |||
262 | void fatalUncheckedError() const; | |||
263 | #endif | |||
264 | ||||
265 | void assertIsChecked() { | |||
266 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 | |||
267 | if (LLVM_UNLIKELY(!getChecked() || getPtr())__builtin_expect((bool)(!getChecked() || getPtr()), false)) | |||
268 | fatalUncheckedError(); | |||
269 | #endif | |||
270 | } | |||
271 | ||||
272 | ErrorInfoBase *getPtr() const { | |||
273 | return reinterpret_cast<ErrorInfoBase*>( | |||
274 | reinterpret_cast<uintptr_t>(Payload) & | |||
275 | ~static_cast<uintptr_t>(0x1)); | |||
276 | } | |||
277 | ||||
278 | void setPtr(ErrorInfoBase *EI) { | |||
279 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 | |||
280 | Payload = reinterpret_cast<ErrorInfoBase*>( | |||
281 | (reinterpret_cast<uintptr_t>(EI) & | |||
282 | ~static_cast<uintptr_t>(0x1)) | | |||
283 | (reinterpret_cast<uintptr_t>(Payload) & 0x1)); | |||
284 | #else | |||
285 | Payload = EI; | |||
286 | #endif | |||
287 | } | |||
288 | ||||
289 | bool getChecked() const { | |||
290 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 | |||
291 | return (reinterpret_cast<uintptr_t>(Payload) & 0x1) == 0; | |||
292 | #else | |||
293 | return true; | |||
294 | #endif | |||
295 | } | |||
296 | ||||
297 | void setChecked(bool V) { | |||
298 | Payload = reinterpret_cast<ErrorInfoBase*>( | |||
299 | (reinterpret_cast<uintptr_t>(Payload) & | |||
300 | ~static_cast<uintptr_t>(0x1)) | | |||
301 | (V ? 0 : 1)); | |||
302 | } | |||
303 | ||||
304 | std::unique_ptr<ErrorInfoBase> takePayload() { | |||
305 | std::unique_ptr<ErrorInfoBase> Tmp(getPtr()); | |||
306 | setPtr(nullptr); | |||
307 | setChecked(true); | |||
308 | return Tmp; | |||
309 | } | |||
310 | ||||
311 | friend raw_ostream &operator<<(raw_ostream &OS, const Error &E) { | |||
312 | if (auto P = E.getPtr()) | |||
313 | P->log(OS); | |||
314 | else | |||
315 | OS << "success"; | |||
316 | return OS; | |||
317 | } | |||
318 | ||||
319 | ErrorInfoBase *Payload = nullptr; | |||
320 | }; | |||
321 | ||||
322 | /// Subclass of Error for the sole purpose of identifying the success path in | |||
323 | /// the type system. This allows to catch invalid conversion to Expected<T> at | |||
324 | /// compile time. | |||
325 | class ErrorSuccess final : public Error {}; | |||
326 | ||||
327 | inline ErrorSuccess Error::success() { return ErrorSuccess(); } | |||
328 | ||||
329 | /// Make a Error instance representing failure using the given error info | |||
330 | /// type. | |||
331 | template <typename ErrT, typename... ArgTs> Error make_error(ArgTs &&... Args) { | |||
332 | return Error(llvm::make_unique<ErrT>(std::forward<ArgTs>(Args)...)); | |||
333 | } | |||
334 | ||||
335 | /// Base class for user error types. Users should declare their error types | |||
336 | /// like: | |||
337 | /// | |||
338 | /// class MyError : public ErrorInfo<MyError> { | |||
339 | /// .... | |||
340 | /// }; | |||
341 | /// | |||
342 | /// This class provides an implementation of the ErrorInfoBase::kind | |||
343 | /// method, which is used by the Error RTTI system. | |||
344 | template <typename ThisErrT, typename ParentErrT = ErrorInfoBase> | |||
345 | class ErrorInfo : public ParentErrT { | |||
346 | public: | |||
347 | using ParentErrT::ParentErrT; // inherit constructors | |||
348 | ||||
349 | static const void *classID() { return &ThisErrT::ID; } | |||
350 | ||||
351 | const void *dynamicClassID() const override { return &ThisErrT::ID; } | |||
352 | ||||
353 | bool isA(const void *const ClassID) const override { | |||
354 | return ClassID == classID() || ParentErrT::isA(ClassID); | |||
355 | } | |||
356 | }; | |||
357 | ||||
358 | /// Special ErrorInfo subclass representing a list of ErrorInfos. | |||
359 | /// Instances of this class are constructed by joinError. | |||
360 | class ErrorList final : public ErrorInfo<ErrorList> { | |||
361 | // handleErrors needs to be able to iterate the payload list of an | |||
362 | // ErrorList. | |||
363 | template <typename... HandlerTs> | |||
364 | friend Error handleErrors(Error E, HandlerTs &&... Handlers); | |||
365 | ||||
366 | // joinErrors is implemented in terms of join. | |||
367 | friend Error joinErrors(Error, Error); | |||
368 | ||||
369 | public: | |||
370 | void log(raw_ostream &OS) const override { | |||
371 | OS << "Multiple errors:\n"; | |||
372 | for (auto &ErrPayload : Payloads) { | |||
373 | ErrPayload->log(OS); | |||
374 | OS << "\n"; | |||
375 | } | |||
376 | } | |||
377 | ||||
378 | std::error_code convertToErrorCode() const override; | |||
379 | ||||
380 | // Used by ErrorInfo::classID. | |||
381 | static char ID; | |||
382 | ||||
383 | private: | |||
384 | ErrorList(std::unique_ptr<ErrorInfoBase> Payload1, | |||
385 | std::unique_ptr<ErrorInfoBase> Payload2) { | |||
386 | assert(!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() &&((!Payload1->isA<ErrorList>() && !Payload2-> isA<ErrorList>() && "ErrorList constructor payloads should be singleton errors" ) ? static_cast<void> (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\"" , "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h" , 387, __PRETTY_FUNCTION__)) | |||
387 | "ErrorList constructor payloads should be singleton errors")((!Payload1->isA<ErrorList>() && !Payload2-> isA<ErrorList>() && "ErrorList constructor payloads should be singleton errors" ) ? static_cast<void> (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\"" , "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h" , 387, __PRETTY_FUNCTION__)); | |||
388 | Payloads.push_back(std::move(Payload1)); | |||
389 | Payloads.push_back(std::move(Payload2)); | |||
390 | } | |||
391 | ||||
392 | static Error join(Error E1, Error E2) { | |||
393 | if (!E1) | |||
394 | return E2; | |||
395 | if (!E2) | |||
396 | return E1; | |||
397 | if (E1.isA<ErrorList>()) { | |||
398 | auto &E1List = static_cast<ErrorList &>(*E1.getPtr()); | |||
399 | if (E2.isA<ErrorList>()) { | |||
400 | auto E2Payload = E2.takePayload(); | |||
401 | auto &E2List = static_cast<ErrorList &>(*E2Payload); | |||
402 | for (auto &Payload : E2List.Payloads) | |||
403 | E1List.Payloads.push_back(std::move(Payload)); | |||
404 | } else | |||
405 | E1List.Payloads.push_back(E2.takePayload()); | |||
406 | ||||
407 | return E1; | |||
408 | } | |||
409 | if (E2.isA<ErrorList>()) { | |||
410 | auto &E2List = static_cast<ErrorList &>(*E2.getPtr()); | |||
411 | E2List.Payloads.insert(E2List.Payloads.begin(), E1.takePayload()); | |||
412 | return E2; | |||
413 | } | |||
414 | return Error(std::unique_ptr<ErrorList>( | |||
415 | new ErrorList(E1.takePayload(), E2.takePayload()))); | |||
416 | } | |||
417 | ||||
418 | std::vector<std::unique_ptr<ErrorInfoBase>> Payloads; | |||
419 | }; | |||
420 | ||||
421 | /// Concatenate errors. The resulting Error is unchecked, and contains the | |||
422 | /// ErrorInfo(s), if any, contained in E1, followed by the | |||
423 | /// ErrorInfo(s), if any, contained in E2. | |||
424 | inline Error joinErrors(Error E1, Error E2) { | |||
425 | return ErrorList::join(std::move(E1), std::move(E2)); | |||
426 | } | |||
427 | ||||
428 | /// Tagged union holding either a T or a Error. | |||
429 | /// | |||
430 | /// This class parallels ErrorOr, but replaces error_code with Error. Since | |||
431 | /// Error cannot be copied, this class replaces getError() with | |||
432 | /// takeError(). It also adds an bool errorIsA<ErrT>() method for testing the | |||
433 | /// error class type. | |||
434 | template <class T> class LLVM_NODISCARD[[clang::warn_unused_result]] Expected { | |||
435 | template <class T1> friend class ExpectedAsOutParameter; | |||
436 | template <class OtherT> friend class Expected; | |||
437 | ||||
438 | static const bool isRef = std::is_reference<T>::value; | |||
439 | ||||
440 | using wrap = std::reference_wrapper<typename std::remove_reference<T>::type>; | |||
441 | ||||
442 | using error_type = std::unique_ptr<ErrorInfoBase>; | |||
443 | ||||
444 | public: | |||
445 | using storage_type = typename std::conditional<isRef, wrap, T>::type; | |||
446 | using value_type = T; | |||
447 | ||||
448 | private: | |||
449 | using reference = typename std::remove_reference<T>::type &; | |||
450 | using const_reference = const typename std::remove_reference<T>::type &; | |||
451 | using pointer = typename std::remove_reference<T>::type *; | |||
452 | using const_pointer = const typename std::remove_reference<T>::type *; | |||
453 | ||||
454 | public: | |||
455 | /// Create an Expected<T> error value from the given Error. | |||
456 | Expected(Error Err) | |||
457 | : HasError(true) | |||
458 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 | |||
459 | // Expected is unchecked upon construction in Debug builds. | |||
460 | , Unchecked(true) | |||
461 | #endif | |||
462 | { | |||
463 | assert(Err && "Cannot create Expected<T> from Error success value.")((Err && "Cannot create Expected<T> from Error success value." ) ? static_cast<void> (0) : __assert_fail ("Err && \"Cannot create Expected<T> from Error success value.\"" , "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h" , 463, __PRETTY_FUNCTION__)); | |||
464 | new (getErrorStorage()) error_type(Err.takePayload()); | |||
465 | } | |||
466 | ||||
467 | /// Forbid to convert from Error::success() implicitly, this avoids having | |||
468 | /// Expected<T> foo() { return Error::success(); } which compiles otherwise | |||
469 | /// but triggers the assertion above. | |||
470 | Expected(ErrorSuccess) = delete; | |||
471 | ||||
472 | /// Create an Expected<T> success value from the given OtherT value, which | |||
473 | /// must be convertible to T. | |||
474 | template <typename OtherT> | |||
475 | Expected(OtherT &&Val, | |||
476 | typename std::enable_if<std::is_convertible<OtherT, T>::value>::type | |||
477 | * = nullptr) | |||
478 | : HasError(false) | |||
479 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 | |||
480 | // Expected is unchecked upon construction in Debug builds. | |||
481 | , Unchecked(true) | |||
482 | #endif | |||
483 | { | |||
484 | new (getStorage()) storage_type(std::forward<OtherT>(Val)); | |||
485 | } | |||
486 | ||||
487 | /// Move construct an Expected<T> value. | |||
488 | Expected(Expected &&Other) { moveConstruct(std::move(Other)); } | |||
489 | ||||
490 | /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT | |||
491 | /// must be convertible to T. | |||
492 | template <class OtherT> | |||
493 | Expected(Expected<OtherT> &&Other, | |||
494 | typename std::enable_if<std::is_convertible<OtherT, T>::value>::type | |||
495 | * = nullptr) { | |||
496 | moveConstruct(std::move(Other)); | |||
497 | } | |||
498 | ||||
499 | /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT | |||
500 | /// isn't convertible to T. | |||
501 | template <class OtherT> | |||
502 | explicit Expected( | |||
503 | Expected<OtherT> &&Other, | |||
504 | typename std::enable_if<!std::is_convertible<OtherT, T>::value>::type * = | |||
505 | nullptr) { | |||
506 | moveConstruct(std::move(Other)); | |||
507 | } | |||
508 | ||||
509 | /// Move-assign from another Expected<T>. | |||
510 | Expected &operator=(Expected &&Other) { | |||
511 | moveAssign(std::move(Other)); | |||
512 | return *this; | |||
513 | } | |||
514 | ||||
515 | /// Destroy an Expected<T>. | |||
516 | ~Expected() { | |||
517 | assertIsChecked(); | |||
518 | if (!HasError) | |||
519 | getStorage()->~storage_type(); | |||
520 | else | |||
521 | getErrorStorage()->~error_type(); | |||
522 | } | |||
523 | ||||
524 | /// Return false if there is an error. | |||
525 | explicit operator bool() { | |||
526 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 | |||
527 | Unchecked = HasError; | |||
528 | #endif | |||
529 | return !HasError; | |||
530 | } | |||
531 | ||||
532 | /// Returns a reference to the stored T value. | |||
533 | reference get() { | |||
534 | assertIsChecked(); | |||
535 | return *getStorage(); | |||
536 | } | |||
537 | ||||
538 | /// Returns a const reference to the stored T value. | |||
539 | const_reference get() const { | |||
540 | assertIsChecked(); | |||
541 | return const_cast<Expected<T> *>(this)->get(); | |||
542 | } | |||
543 | ||||
544 | /// Check that this Expected<T> is an error of type ErrT. | |||
545 | template <typename ErrT> bool errorIsA() const { | |||
546 | return HasError && (*getErrorStorage())->template isA<ErrT>(); | |||
547 | } | |||
548 | ||||
549 | /// Take ownership of the stored error. | |||
550 | /// After calling this the Expected<T> is in an indeterminate state that can | |||
551 | /// only be safely destructed. No further calls (beside the destructor) should | |||
552 | /// be made on the Expected<T> vaule. | |||
553 | Error takeError() { | |||
554 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 | |||
555 | Unchecked = false; | |||
556 | #endif | |||
557 | return HasError ? Error(std::move(*getErrorStorage())) : Error::success(); | |||
558 | } | |||
559 | ||||
560 | /// Returns a pointer to the stored T value. | |||
561 | pointer operator->() { | |||
562 | assertIsChecked(); | |||
563 | return toPointer(getStorage()); | |||
564 | } | |||
565 | ||||
566 | /// Returns a const pointer to the stored T value. | |||
567 | const_pointer operator->() const { | |||
568 | assertIsChecked(); | |||
569 | return toPointer(getStorage()); | |||
570 | } | |||
571 | ||||
572 | /// Returns a reference to the stored T value. | |||
573 | reference operator*() { | |||
574 | assertIsChecked(); | |||
575 | return *getStorage(); | |||
576 | } | |||
577 | ||||
578 | /// Returns a const reference to the stored T value. | |||
579 | const_reference operator*() const { | |||
580 | assertIsChecked(); | |||
581 | return *getStorage(); | |||
582 | } | |||
583 | ||||
584 | private: | |||
585 | template <class T1> | |||
586 | static bool compareThisIfSameType(const T1 &a, const T1 &b) { | |||
587 | return &a == &b; | |||
588 | } | |||
589 | ||||
590 | template <class T1, class T2> | |||
591 | static bool compareThisIfSameType(const T1 &a, const T2 &b) { | |||
592 | return false; | |||
593 | } | |||
594 | ||||
595 | template <class OtherT> void moveConstruct(Expected<OtherT> &&Other) { | |||
596 | HasError = Other.HasError; | |||
597 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 | |||
598 | Unchecked = true; | |||
599 | Other.Unchecked = false; | |||
600 | #endif | |||
601 | ||||
602 | if (!HasError) | |||
603 | new (getStorage()) storage_type(std::move(*Other.getStorage())); | |||
604 | else | |||
605 | new (getErrorStorage()) error_type(std::move(*Other.getErrorStorage())); | |||
606 | } | |||
607 | ||||
608 | template <class OtherT> void moveAssign(Expected<OtherT> &&Other) { | |||
609 | assertIsChecked(); | |||
610 | ||||
611 | if (compareThisIfSameType(*this, Other)) | |||
612 | return; | |||
613 | ||||
614 | this->~Expected(); | |||
615 | new (this) Expected(std::move(Other)); | |||
616 | } | |||
617 | ||||
618 | pointer toPointer(pointer Val) { return Val; } | |||
619 | ||||
620 | const_pointer toPointer(const_pointer Val) const { return Val; } | |||
621 | ||||
622 | pointer toPointer(wrap *Val) { return &Val->get(); } | |||
623 | ||||
624 | const_pointer toPointer(const wrap *Val) const { return &Val->get(); } | |||
625 | ||||
626 | storage_type *getStorage() { | |||
627 | assert(!HasError && "Cannot get value when an error exists!")((!HasError && "Cannot get value when an error exists!" ) ? static_cast<void> (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\"" , "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h" , 627, __PRETTY_FUNCTION__)); | |||
628 | return reinterpret_cast<storage_type *>(TStorage.buffer); | |||
629 | } | |||
630 | ||||
631 | const storage_type *getStorage() const { | |||
632 | assert(!HasError && "Cannot get value when an error exists!")((!HasError && "Cannot get value when an error exists!" ) ? static_cast<void> (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\"" , "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h" , 632, __PRETTY_FUNCTION__)); | |||
633 | return reinterpret_cast<const storage_type *>(TStorage.buffer); | |||
634 | } | |||
635 | ||||
636 | error_type *getErrorStorage() { | |||
637 | assert(HasError && "Cannot get error when a value exists!")((HasError && "Cannot get error when a value exists!" ) ? static_cast<void> (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\"" , "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h" , 637, __PRETTY_FUNCTION__)); | |||
638 | return reinterpret_cast<error_type *>(ErrorStorage.buffer); | |||
639 | } | |||
640 | ||||
641 | const error_type *getErrorStorage() const { | |||
642 | assert(HasError && "Cannot get error when a value exists!")((HasError && "Cannot get error when a value exists!" ) ? static_cast<void> (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\"" , "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h" , 642, __PRETTY_FUNCTION__)); | |||
643 | return reinterpret_cast<const error_type *>(ErrorStorage.buffer); | |||
644 | } | |||
645 | ||||
646 | // Used by ExpectedAsOutParameter to reset the checked flag. | |||
647 | void setUnchecked() { | |||
648 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 | |||
649 | Unchecked = true; | |||
650 | #endif | |||
651 | } | |||
652 | ||||
653 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 | |||
654 | LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn)) | |||
655 | LLVM_ATTRIBUTE_NOINLINE__attribute__((noinline)) | |||
656 | void fatalUncheckedExpected() const { | |||
657 | dbgs() << "Expected<T> must be checked before access or destruction.\n"; | |||
658 | if (HasError) { | |||
659 | dbgs() << "Unchecked Expected<T> contained error:\n"; | |||
660 | (*getErrorStorage())->log(dbgs()); | |||
661 | } else | |||
662 | dbgs() << "Expected<T> value was in success state. (Note: Expected<T> " | |||
663 | "values in success mode must still be checked prior to being " | |||
664 | "destroyed).\n"; | |||
665 | abort(); | |||
666 | } | |||
667 | #endif | |||
668 | ||||
669 | void assertIsChecked() { | |||
670 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 | |||
671 | if (LLVM_UNLIKELY(Unchecked)__builtin_expect((bool)(Unchecked), false)) | |||
672 | fatalUncheckedExpected(); | |||
673 | #endif | |||
674 | } | |||
675 | ||||
676 | union { | |||
677 | AlignedCharArrayUnion<storage_type> TStorage; | |||
678 | AlignedCharArrayUnion<error_type> ErrorStorage; | |||
679 | }; | |||
680 | bool HasError : 1; | |||
681 | #if LLVM_ENABLE_ABI_BREAKING_CHECKS1 | |||
682 | bool Unchecked : 1; | |||
683 | #endif | |||
684 | }; | |||
685 | ||||
686 | /// Report a serious error, calling any installed error handler. See | |||
687 | /// ErrorHandling.h. | |||
688 | LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn)) void report_fatal_error(Error Err, | |||
689 | bool gen_crash_diag = true); | |||
690 | ||||
691 | /// Report a fatal error if Err is a failure value. | |||
692 | /// | |||
693 | /// This function can be used to wrap calls to fallible functions ONLY when it | |||
694 | /// is known that the Error will always be a success value. E.g. | |||
695 | /// | |||
696 | /// @code{.cpp} | |||
697 | /// // foo only attempts the fallible operation if DoFallibleOperation is | |||
698 | /// // true. If DoFallibleOperation is false then foo always returns | |||
699 | /// // Error::success(). | |||
700 | /// Error foo(bool DoFallibleOperation); | |||
701 | /// | |||
702 | /// cantFail(foo(false)); | |||
703 | /// @endcode | |||
704 | inline void cantFail(Error Err, const char *Msg = nullptr) { | |||
705 | if (Err) { | |||
706 | if (!Msg) | |||
707 | Msg = "Failure value returned from cantFail wrapped call"; | |||
708 | llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h" , 708); | |||
709 | } | |||
710 | } | |||
711 | ||||
712 | /// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and | |||
713 | /// returns the contained value. | |||
714 | /// | |||
715 | /// This function can be used to wrap calls to fallible functions ONLY when it | |||
716 | /// is known that the Error will always be a success value. E.g. | |||
717 | /// | |||
718 | /// @code{.cpp} | |||
719 | /// // foo only attempts the fallible operation if DoFallibleOperation is | |||
720 | /// // true. If DoFallibleOperation is false then foo always returns an int. | |||
721 | /// Expected<int> foo(bool DoFallibleOperation); | |||
722 | /// | |||
723 | /// int X = cantFail(foo(false)); | |||
724 | /// @endcode | |||
725 | template <typename T> | |||
726 | T cantFail(Expected<T> ValOrErr, const char *Msg = nullptr) { | |||
727 | if (ValOrErr) | |||
728 | return std::move(*ValOrErr); | |||
729 | else { | |||
730 | if (!Msg) | |||
731 | Msg = "Failure value returned from cantFail wrapped call"; | |||
732 | llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h" , 732); | |||
733 | } | |||
734 | } | |||
735 | ||||
736 | /// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and | |||
737 | /// returns the contained reference. | |||
738 | /// | |||
739 | /// This function can be used to wrap calls to fallible functions ONLY when it | |||
740 | /// is known that the Error will always be a success value. E.g. | |||
741 | /// | |||
742 | /// @code{.cpp} | |||
743 | /// // foo only attempts the fallible operation if DoFallibleOperation is | |||
744 | /// // true. If DoFallibleOperation is false then foo always returns a Bar&. | |||
745 | /// Expected<Bar&> foo(bool DoFallibleOperation); | |||
746 | /// | |||
747 | /// Bar &X = cantFail(foo(false)); | |||
748 | /// @endcode | |||
749 | template <typename T> | |||
750 | T& cantFail(Expected<T&> ValOrErr, const char *Msg = nullptr) { | |||
751 | if (ValOrErr) | |||
752 | return *ValOrErr; | |||
753 | else { | |||
754 | if (!Msg) | |||
755 | Msg = "Failure value returned from cantFail wrapped call"; | |||
756 | llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h" , 756); | |||
757 | } | |||
758 | } | |||
759 | ||||
760 | /// Helper for testing applicability of, and applying, handlers for | |||
761 | /// ErrorInfo types. | |||
762 | template <typename HandlerT> | |||
763 | class ErrorHandlerTraits | |||
764 | : public ErrorHandlerTraits<decltype( | |||
765 | &std::remove_reference<HandlerT>::type::operator())> {}; | |||
766 | ||||
767 | // Specialization functions of the form 'Error (const ErrT&)'. | |||
768 | template <typename ErrT> class ErrorHandlerTraits<Error (&)(ErrT &)> { | |||
769 | public: | |||
770 | static bool appliesTo(const ErrorInfoBase &E) { | |||
771 | return E.template isA<ErrT>(); | |||
772 | } | |||
773 | ||||
774 | template <typename HandlerT> | |||
775 | static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) { | |||
776 | assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast <void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\"" , "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h" , 776, __PRETTY_FUNCTION__)); | |||
777 | return H(static_cast<ErrT &>(*E)); | |||
778 | } | |||
779 | }; | |||
780 | ||||
781 | // Specialization functions of the form 'void (const ErrT&)'. | |||
782 | template <typename ErrT> class ErrorHandlerTraits<void (&)(ErrT &)> { | |||
783 | public: | |||
784 | static bool appliesTo(const ErrorInfoBase &E) { | |||
785 | return E.template isA<ErrT>(); | |||
786 | } | |||
787 | ||||
788 | template <typename HandlerT> | |||
789 | static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) { | |||
790 | assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast <void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\"" , "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h" , 790, __PRETTY_FUNCTION__)); | |||
791 | H(static_cast<ErrT &>(*E)); | |||
792 | return Error::success(); | |||
793 | } | |||
794 | }; | |||
795 | ||||
796 | /// Specialization for functions of the form 'Error (std::unique_ptr<ErrT>)'. | |||
797 | template <typename ErrT> | |||
798 | class ErrorHandlerTraits<Error (&)(std::unique_ptr<ErrT>)> { | |||
799 | public: | |||
800 | static bool appliesTo(const ErrorInfoBase &E) { | |||
801 | return E.template isA<ErrT>(); | |||
802 | } | |||
803 | ||||
804 | template <typename HandlerT> | |||
805 | static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) { | |||
806 | assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast <void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\"" , "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h" , 806, __PRETTY_FUNCTION__)); | |||
807 | std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release())); | |||
808 | return H(std::move(SubE)); | |||
809 | } | |||
810 | }; | |||
811 | ||||
812 | /// Specialization for functions of the form 'void (std::unique_ptr<ErrT>)'. | |||
813 | template <typename ErrT> | |||
814 | class ErrorHandlerTraits<void (&)(std::unique_ptr<ErrT>)> { | |||
815 | public: | |||
816 | static bool appliesTo(const ErrorInfoBase &E) { | |||
817 | return E.template isA<ErrT>(); | |||
818 | } | |||
819 | ||||
820 | template <typename HandlerT> | |||
821 | static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) { | |||
822 | assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast <void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\"" , "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h" , 822, __PRETTY_FUNCTION__)); | |||
823 | std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release())); | |||
824 | H(std::move(SubE)); | |||
825 | return Error::success(); | |||
826 | } | |||
827 | }; | |||
828 | ||||
829 | // Specialization for member functions of the form 'RetT (const ErrT&)'. | |||
830 | template <typename C, typename RetT, typename ErrT> | |||
831 | class ErrorHandlerTraits<RetT (C::*)(ErrT &)> | |||
832 | : public ErrorHandlerTraits<RetT (&)(ErrT &)> {}; | |||
833 | ||||
834 | // Specialization for member functions of the form 'RetT (const ErrT&) const'. | |||
835 | template <typename C, typename RetT, typename ErrT> | |||
836 | class ErrorHandlerTraits<RetT (C::*)(ErrT &) const> | |||
837 | : public ErrorHandlerTraits<RetT (&)(ErrT &)> {}; | |||
838 | ||||
839 | // Specialization for member functions of the form 'RetT (const ErrT&)'. | |||
840 | template <typename C, typename RetT, typename ErrT> | |||
841 | class ErrorHandlerTraits<RetT (C::*)(const ErrT &)> | |||
842 | : public ErrorHandlerTraits<RetT (&)(ErrT &)> {}; | |||
843 | ||||
844 | // Specialization for member functions of the form 'RetT (const ErrT&) const'. | |||
845 | template <typename C, typename RetT, typename ErrT> | |||
846 | class ErrorHandlerTraits<RetT (C::*)(const ErrT &) const> | |||
847 | : public ErrorHandlerTraits<RetT (&)(ErrT &)> {}; | |||
848 | ||||
849 | /// Specialization for member functions of the form | |||
850 | /// 'RetT (std::unique_ptr<ErrT>)'. | |||
851 | template <typename C, typename RetT, typename ErrT> | |||
852 | class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>)> | |||
853 | : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {}; | |||
854 | ||||
855 | /// Specialization for member functions of the form | |||
856 | /// 'RetT (std::unique_ptr<ErrT>) const'. | |||
857 | template <typename C, typename RetT, typename ErrT> | |||
858 | class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>) const> | |||
859 | : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {}; | |||
860 | ||||
861 | inline Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload) { | |||
862 | return Error(std::move(Payload)); | |||
863 | } | |||
864 | ||||
865 | template <typename HandlerT, typename... HandlerTs> | |||
866 | Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload, | |||
867 | HandlerT &&Handler, HandlerTs &&... Handlers) { | |||
868 | if (ErrorHandlerTraits<HandlerT>::appliesTo(*Payload)) | |||
869 | return ErrorHandlerTraits<HandlerT>::apply(std::forward<HandlerT>(Handler), | |||
870 | std::move(Payload)); | |||
871 | return handleErrorImpl(std::move(Payload), | |||
872 | std::forward<HandlerTs>(Handlers)...); | |||
873 | } | |||
874 | ||||
875 | /// Pass the ErrorInfo(s) contained in E to their respective handlers. Any | |||
876 | /// unhandled errors (or Errors returned by handlers) are re-concatenated and | |||
877 | /// returned. | |||
878 | /// Because this function returns an error, its result must also be checked | |||
879 | /// or returned. If you intend to handle all errors use handleAllErrors | |||
880 | /// (which returns void, and will abort() on unhandled errors) instead. | |||
881 | template <typename... HandlerTs> | |||
882 | Error handleErrors(Error E, HandlerTs &&... Hs) { | |||
883 | if (!E) | |||
884 | return Error::success(); | |||
885 | ||||
886 | std::unique_ptr<ErrorInfoBase> Payload = E.takePayload(); | |||
887 | ||||
888 | if (Payload->isA<ErrorList>()) { | |||
889 | ErrorList &List = static_cast<ErrorList &>(*Payload); | |||
890 | Error R; | |||
891 | for (auto &P : List.Payloads) | |||
892 | R = ErrorList::join( | |||
893 | std::move(R), | |||
894 | handleErrorImpl(std::move(P), std::forward<HandlerTs>(Hs)...)); | |||
895 | return R; | |||
896 | } | |||
897 | ||||
898 | return handleErrorImpl(std::move(Payload), std::forward<HandlerTs>(Hs)...); | |||
899 | } | |||
900 | ||||
901 | /// Behaves the same as handleErrors, except that by contract all errors | |||
902 | /// *must* be handled by the given handlers (i.e. there must be no remaining | |||
903 | /// errors after running the handlers, or llvm_unreachable is called). | |||
904 | template <typename... HandlerTs> | |||
905 | void handleAllErrors(Error E, HandlerTs &&... Handlers) { | |||
906 | cantFail(handleErrors(std::move(E), std::forward<HandlerTs>(Handlers)...)); | |||
907 | } | |||
908 | ||||
909 | /// Check that E is a non-error, then drop it. | |||
910 | /// If E is an error, llvm_unreachable will be called. | |||
911 | inline void handleAllErrors(Error E) { | |||
912 | cantFail(std::move(E)); | |||
913 | } | |||
914 | ||||
915 | /// Handle any errors (if present) in an Expected<T>, then try a recovery path. | |||
916 | /// | |||
917 | /// If the incoming value is a success value it is returned unmodified. If it | |||
918 | /// is a failure value then it the contained error is passed to handleErrors. | |||
919 | /// If handleErrors is able to handle the error then the RecoveryPath functor | |||
920 | /// is called to supply the final result. If handleErrors is not able to | |||
921 | /// handle all errors then the unhandled errors are returned. | |||
922 | /// | |||
923 | /// This utility enables the follow pattern: | |||
924 | /// | |||
925 | /// @code{.cpp} | |||
926 | /// enum FooStrategy { Aggressive, Conservative }; | |||
927 | /// Expected<Foo> foo(FooStrategy S); | |||
928 | /// | |||
929 | /// auto ResultOrErr = | |||
930 | /// handleExpected( | |||
931 | /// foo(Aggressive), | |||
932 | /// []() { return foo(Conservative); }, | |||
933 | /// [](AggressiveStrategyError&) { | |||
934 | /// // Implicitly conusme this - we'll recover by using a conservative | |||
935 | /// // strategy. | |||
936 | /// }); | |||
937 | /// | |||
938 | /// @endcode | |||
939 | template <typename T, typename RecoveryFtor, typename... HandlerTs> | |||
940 | Expected<T> handleExpected(Expected<T> ValOrErr, RecoveryFtor &&RecoveryPath, | |||
941 | HandlerTs &&... Handlers) { | |||
942 | if (ValOrErr) | |||
943 | return ValOrErr; | |||
944 | ||||
945 | if (auto Err = handleErrors(ValOrErr.takeError(), | |||
946 | std::forward<HandlerTs>(Handlers)...)) | |||
947 | return std::move(Err); | |||
948 | ||||
949 | return RecoveryPath(); | |||
950 | } | |||
951 | ||||
952 | /// Log all errors (if any) in E to OS. If there are any errors, ErrorBanner | |||
953 | /// will be printed before the first one is logged. A newline will be printed | |||
954 | /// after each error. | |||
955 | /// | |||
956 | /// This is useful in the base level of your program to allow clean termination | |||
957 | /// (allowing clean deallocation of resources, etc.), while reporting error | |||
958 | /// information to the user. | |||
959 | void logAllUnhandledErrors(Error E, raw_ostream &OS, Twine ErrorBanner); | |||
960 | ||||
961 | /// Write all error messages (if any) in E to a string. The newline character | |||
962 | /// is used to separate error messages. | |||
963 | inline std::string toString(Error E) { | |||
964 | SmallVector<std::string, 2> Errors; | |||
965 | handleAllErrors(std::move(E), [&Errors](const ErrorInfoBase &EI) { | |||
966 | Errors.push_back(EI.message()); | |||
967 | }); | |||
968 | return join(Errors.begin(), Errors.end(), "\n"); | |||
969 | } | |||
970 | ||||
971 | /// Consume a Error without doing anything. This method should be used | |||
972 | /// only where an error can be considered a reasonable and expected return | |||
973 | /// value. | |||
974 | /// | |||
975 | /// Uses of this method are potentially indicative of design problems: If it's | |||
976 | /// legitimate to do nothing while processing an "error", the error-producer | |||
977 | /// might be more clearly refactored to return an Optional<T>. | |||
978 | inline void consumeError(Error Err) { | |||
979 | handleAllErrors(std::move(Err), [](const ErrorInfoBase &) {}); | |||
980 | } | |||
981 | ||||
982 | /// Helper for converting an Error to a bool. | |||
983 | /// | |||
984 | /// This method returns true if Err is in an error state, or false if it is | |||
985 | /// in a success state. Puts Err in a checked state in both cases (unlike | |||
986 | /// Error::operator bool(), which only does this for success states). | |||
987 | inline bool errorToBool(Error Err) { | |||
988 | bool IsError = static_cast<bool>(Err); | |||
989 | if (IsError) | |||
990 | consumeError(std::move(Err)); | |||
991 | return IsError; | |||
992 | } | |||
993 | ||||
994 | /// Helper for Errors used as out-parameters. | |||
995 | /// | |||
996 | /// This helper is for use with the Error-as-out-parameter idiom, where an error | |||
997 | /// is passed to a function or method by reference, rather than being returned. | |||
998 | /// In such cases it is helpful to set the checked bit on entry to the function | |||
999 | /// so that the error can be written to (unchecked Errors abort on assignment) | |||
1000 | /// and clear the checked bit on exit so that clients cannot accidentally forget | |||
1001 | /// to check the result. This helper performs these actions automatically using | |||
1002 | /// RAII: | |||
1003 | /// | |||
1004 | /// @code{.cpp} | |||
1005 | /// Result foo(Error &Err) { | |||
1006 | /// ErrorAsOutParameter ErrAsOutParam(&Err); // 'Checked' flag set | |||
1007 | /// // <body of foo> | |||
1008 | /// // <- 'Checked' flag auto-cleared when ErrAsOutParam is destructed. | |||
1009 | /// } | |||
1010 | /// @endcode | |||
1011 | /// | |||
1012 | /// ErrorAsOutParameter takes an Error* rather than Error& so that it can be | |||
1013 | /// used with optional Errors (Error pointers that are allowed to be null). If | |||
1014 | /// ErrorAsOutParameter took an Error reference, an instance would have to be | |||
1015 | /// created inside every condition that verified that Error was non-null. By | |||
1016 | /// taking an Error pointer we can just create one instance at the top of the | |||
1017 | /// function. | |||
1018 | class ErrorAsOutParameter { | |||
1019 | public: | |||
1020 | ErrorAsOutParameter(Error *Err) : Err(Err) { | |||
1021 | // Raise the checked bit if Err is success. | |||
1022 | if (Err) | |||
1023 | (void)!!*Err; | |||
1024 | } | |||
1025 | ||||
1026 | ~ErrorAsOutParameter() { | |||
1027 | // Clear the checked bit. | |||
1028 | if (Err && !*Err) | |||
1029 | *Err = Error::success(); | |||
1030 | } | |||
1031 | ||||
1032 | private: | |||
1033 | Error *Err; | |||
1034 | }; | |||
1035 | ||||
1036 | /// Helper for Expected<T>s used as out-parameters. | |||
1037 | /// | |||
1038 | /// See ErrorAsOutParameter. | |||
1039 | template <typename T> | |||
1040 | class ExpectedAsOutParameter { | |||
1041 | public: | |||
1042 | ExpectedAsOutParameter(Expected<T> *ValOrErr) | |||
1043 | : ValOrErr(ValOrErr) { | |||
1044 | if (ValOrErr) | |||
1045 | (void)!!*ValOrErr; | |||
1046 | } | |||
1047 | ||||
1048 | ~ExpectedAsOutParameter() { | |||
1049 | if (ValOrErr) | |||
1050 | ValOrErr->setUnchecked(); | |||
1051 | } | |||
1052 | ||||
1053 | private: | |||
1054 | Expected<T> *ValOrErr; | |||
1055 | }; | |||
1056 | ||||
1057 | /// This class wraps a std::error_code in a Error. | |||
1058 | /// | |||
1059 | /// This is useful if you're writing an interface that returns a Error | |||
1060 | /// (or Expected) and you want to call code that still returns | |||
1061 | /// std::error_codes. | |||
1062 | class ECError : public ErrorInfo<ECError> { | |||
1063 | friend Error errorCodeToError(std::error_code); | |||
1064 | ||||
1065 | public: | |||
1066 | void setErrorCode(std::error_code EC) { this->EC = EC; } | |||
1067 | std::error_code convertToErrorCode() const override { return EC; } | |||
1068 | void log(raw_ostream &OS) const override { OS << EC.message(); } | |||
1069 | ||||
1070 | // Used by ErrorInfo::classID. | |||
1071 | static char ID; | |||
1072 | ||||
1073 | protected: | |||
1074 | ECError() = default; | |||
1075 | ECError(std::error_code EC) : EC(EC) {} | |||
1076 | ||||
1077 | std::error_code EC; | |||
1078 | }; | |||
1079 | ||||
1080 | /// The value returned by this function can be returned from convertToErrorCode | |||
1081 | /// for Error values where no sensible translation to std::error_code exists. | |||
1082 | /// It should only be used in this situation, and should never be used where a | |||
1083 | /// sensible conversion to std::error_code is available, as attempts to convert | |||
1084 | /// to/from this error will result in a fatal error. (i.e. it is a programmatic | |||
1085 | ///error to try to convert such a value). | |||
1086 | std::error_code inconvertibleErrorCode(); | |||
1087 | ||||
1088 | /// Helper for converting an std::error_code to a Error. | |||
1089 | Error errorCodeToError(std::error_code EC); | |||
1090 | ||||
1091 | /// Helper for converting an ECError to a std::error_code. | |||
1092 | /// | |||
1093 | /// This method requires that Err be Error() or an ECError, otherwise it | |||
1094 | /// will trigger a call to abort(). | |||
1095 | std::error_code errorToErrorCode(Error Err); | |||
1096 | ||||
1097 | /// Convert an ErrorOr<T> to an Expected<T>. | |||
1098 | template <typename T> Expected<T> errorOrToExpected(ErrorOr<T> &&EO) { | |||
1099 | if (auto EC = EO.getError()) | |||
1100 | return errorCodeToError(EC); | |||
1101 | return std::move(*EO); | |||
1102 | } | |||
1103 | ||||
1104 | /// Convert an Expected<T> to an ErrorOr<T>. | |||
1105 | template <typename T> ErrorOr<T> expectedToErrorOr(Expected<T> &&E) { | |||
1106 | if (auto Err = E.takeError()) | |||
1107 | return errorToErrorCode(std::move(Err)); | |||
1108 | return std::move(*E); | |||
1109 | } | |||
1110 | ||||
1111 | /// This class wraps a string in an Error. | |||
1112 | /// | |||
1113 | /// StringError is useful in cases where the client is not expected to be able | |||
1114 | /// to consume the specific error message programmatically (for example, if the | |||
1115 | /// error message is to be presented to the user). | |||
1116 | /// | |||
1117 | /// StringError can also be used when additional information is to be printed | |||
1118 | /// along with a error_code message. Depending on the constructor called, this | |||
1119 | /// class can either display: | |||
1120 | /// 1. the error_code message (ECError behavior) | |||
1121 | /// 2. a string | |||
1122 | /// 3. the error_code message and a string | |||
1123 | /// | |||
1124 | /// These behaviors are useful when subtyping is required; for example, when a | |||
1125 | /// specific library needs an explicit error type. In the example below, | |||
1126 | /// PDBError is derived from StringError: | |||
1127 | /// | |||
1128 | /// @code{.cpp} | |||
1129 | /// Expected<int> foo() { | |||
1130 | /// return llvm::make_error<PDBError>(pdb_error_code::dia_failed_loading, | |||
1131 | /// "Additional information"); | |||
1132 | /// } | |||
1133 | /// @endcode | |||
1134 | /// | |||
1135 | class StringError : public ErrorInfo<StringError> { | |||
1136 | public: | |||
1137 | static char ID; | |||
1138 | ||||
1139 | // Prints EC + S and converts to EC | |||
1140 | StringError(std::error_code EC, const Twine &S = Twine()); | |||
1141 | ||||
1142 | // Prints S and converts to EC | |||
1143 | StringError(const Twine &S, std::error_code EC); | |||
1144 | ||||
1145 | void log(raw_ostream &OS) const override; | |||
1146 | std::error_code convertToErrorCode() const override; | |||
1147 | ||||
1148 | const std::string &getMessage() const { return Msg; } | |||
1149 | ||||
1150 | private: | |||
1151 | std::string Msg; | |||
1152 | std::error_code EC; | |||
1153 | const bool PrintMsgOnly = false; | |||
1154 | }; | |||
1155 | ||||
1156 | /// Create formatted StringError object. | |||
1157 | template <typename... Ts> | |||
1158 | Error createStringError(std::error_code EC, char const *Fmt, | |||
1159 | const Ts &... Vals) { | |||
1160 | std::string Buffer; | |||
1161 | raw_string_ostream Stream(Buffer); | |||
1162 | Stream << format(Fmt, Vals...); | |||
1163 | return make_error<StringError>(Stream.str(), EC); | |||
1164 | } | |||
1165 | ||||
1166 | Error createStringError(std::error_code EC, char const *Msg); | |||
1167 | ||||
1168 | /// This class wraps a filename and another Error. | |||
1169 | /// | |||
1170 | /// In some cases, an error needs to live along a 'source' name, in order to | |||
1171 | /// show more detailed information to the user. | |||
1172 | class FileError final : public ErrorInfo<FileError> { | |||
1173 | ||||
1174 | friend Error createFileError(std::string, Error); | |||
1175 | ||||
1176 | public: | |||
1177 | void log(raw_ostream &OS) const override { | |||
1178 | assert(Err && !FileName.empty() && "Trying to log after takeError().")((Err && !FileName.empty() && "Trying to log after takeError()." ) ? static_cast<void> (0) : __assert_fail ("Err && !FileName.empty() && \"Trying to log after takeError().\"" , "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h" , 1178, __PRETTY_FUNCTION__)); | |||
1179 | OS << "'" << FileName << "': "; | |||
1180 | Err->log(OS); | |||
1181 | } | |||
1182 | ||||
1183 | Error takeError() { return Error(std::move(Err)); } | |||
1184 | ||||
1185 | std::error_code convertToErrorCode() const override; | |||
1186 | ||||
1187 | // Used by ErrorInfo::classID. | |||
1188 | static char ID; | |||
1189 | ||||
1190 | private: | |||
1191 | FileError(std::string F, std::unique_ptr<ErrorInfoBase> E) { | |||
1192 | assert(E && "Cannot create FileError from Error success value.")((E && "Cannot create FileError from Error success value." ) ? static_cast<void> (0) : __assert_fail ("E && \"Cannot create FileError from Error success value.\"" , "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h" , 1192, __PRETTY_FUNCTION__)); | |||
1193 | assert(!F.empty() &&((!F.empty() && "The file name provided to FileError must not be empty." ) ? static_cast<void> (0) : __assert_fail ("!F.empty() && \"The file name provided to FileError must not be empty.\"" , "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h" , 1194, __PRETTY_FUNCTION__)) | |||
1194 | "The file name provided to FileError must not be empty.")((!F.empty() && "The file name provided to FileError must not be empty." ) ? static_cast<void> (0) : __assert_fail ("!F.empty() && \"The file name provided to FileError must not be empty.\"" , "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h" , 1194, __PRETTY_FUNCTION__)); | |||
1195 | FileName = F; | |||
1196 | Err = std::move(E); | |||
1197 | } | |||
1198 | ||||
1199 | static Error build(std::string F, Error E) { | |||
1200 | return Error(std::unique_ptr<FileError>(new FileError(F, E.takePayload()))); | |||
1201 | } | |||
1202 | ||||
1203 | std::string FileName; | |||
1204 | std::unique_ptr<ErrorInfoBase> Err; | |||
1205 | }; | |||
1206 | ||||
1207 | /// Concatenate a source file path and/or name with an Error. The resulting | |||
1208 | /// Error is unchecked. | |||
1209 | inline Error createFileError(std::string F, Error E) { | |||
1210 | return FileError::build(F, std::move(E)); | |||
1211 | } | |||
1212 | ||||
1213 | Error createFileError(std::string F, ErrorSuccess) = delete; | |||
1214 | ||||
1215 | /// Helper for check-and-exit error handling. | |||
1216 | /// | |||
1217 | /// For tool use only. NOT FOR USE IN LIBRARY CODE. | |||
1218 | /// | |||
1219 | class ExitOnError { | |||
1220 | public: | |||
1221 | /// Create an error on exit helper. | |||
1222 | ExitOnError(std::string Banner = "", int DefaultErrorExitCode = 1) | |||
1223 | : Banner(std::move(Banner)), | |||
1224 | GetExitCode([=](const Error &) { return DefaultErrorExitCode; }) {} | |||
1225 | ||||
1226 | /// Set the banner string for any errors caught by operator(). | |||
1227 | void setBanner(std::string Banner) { this->Banner = std::move(Banner); } | |||
1228 | ||||
1229 | /// Set the exit-code mapper function. | |||
1230 | void setExitCodeMapper(std::function<int(const Error &)> GetExitCode) { | |||
1231 | this->GetExitCode = std::move(GetExitCode); | |||
1232 | } | |||
1233 | ||||
1234 | /// Check Err. If it's in a failure state log the error(s) and exit. | |||
1235 | void operator()(Error Err) const { checkError(std::move(Err)); } | |||
1236 | ||||
1237 | /// Check E. If it's in a success state then return the contained value. If | |||
1238 | /// it's in a failure state log the error(s) and exit. | |||
1239 | template <typename T> T operator()(Expected<T> &&E) const { | |||
1240 | checkError(E.takeError()); | |||
1241 | return std::move(*E); | |||
1242 | } | |||
1243 | ||||
1244 | /// Check E. If it's in a success state then return the contained reference. If | |||
1245 | /// it's in a failure state log the error(s) and exit. | |||
1246 | template <typename T> T& operator()(Expected<T&> &&E) const { | |||
1247 | checkError(E.takeError()); | |||
1248 | return *E; | |||
1249 | } | |||
1250 | ||||
1251 | private: | |||
1252 | void checkError(Error Err) const { | |||
1253 | if (Err) { | |||
1254 | int ExitCode = GetExitCode(Err); | |||
1255 | logAllUnhandledErrors(std::move(Err), errs(), Banner); | |||
1256 | exit(ExitCode); | |||
1257 | } | |||
1258 | } | |||
1259 | ||||
1260 | std::string Banner; | |||
1261 | std::function<int(const Error &)> GetExitCode; | |||
1262 | }; | |||
1263 | ||||
1264 | /// Conversion from Error to LLVMErrorRef for C error bindings. | |||
1265 | inline LLVMErrorRef wrap(Error Err) { | |||
1266 | return reinterpret_cast<LLVMErrorRef>(Err.takePayload().release()); | |||
1267 | } | |||
1268 | ||||
1269 | /// Conversion from LLVMErrorRef to Error for C error bindings. | |||
1270 | inline Error unwrap(LLVMErrorRef ErrRef) { | |||
1271 | return Error(std::unique_ptr<ErrorInfoBase>( | |||
1272 | reinterpret_cast<ErrorInfoBase *>(ErrRef))); | |||
1273 | } | |||
1274 | ||||
1275 | } // end namespace llvm | |||
1276 | ||||
1277 | #endif // LLVM_SUPPORT_ERROR_H |