Bug Summary

File:include/llvm/Support/Error.h
Warning:line 200, column 5
Potential leak of memory pointed to by 'Payload._M_t._M_head_impl'

Annotated Source Code

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clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name DWARFDie.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mthread-model posix -fmath-errno -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb -momit-leaf-frame-pointer -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-9/lib/clang/9.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-9~svn362543/build-llvm/lib/DebugInfo/DWARF -I /build/llvm-toolchain-snapshot-9~svn362543/lib/DebugInfo/DWARF -I /build/llvm-toolchain-snapshot-9~svn362543/build-llvm/include -I /build/llvm-toolchain-snapshot-9~svn362543/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/include/clang/9.0.0/include/ -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-9/lib/clang/9.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++11 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-9~svn362543/build-llvm/lib/DebugInfo/DWARF -fdebug-prefix-map=/build/llvm-toolchain-snapshot-9~svn362543=. -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -stack-protector 2 -fobjc-runtime=gcc -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -o /tmp/scan-build-2019-06-05-060531-1271-1 -x c++ /build/llvm-toolchain-snapshot-9~svn362543/lib/DebugInfo/DWARF/DWARFDie.cpp -faddrsig

/build/llvm-toolchain-snapshot-9~svn362543/lib/DebugInfo/DWARF/DWARFDie.cpp

→
1//===- DWARFDie.cpp -------------------------------------------------------===//
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#include "llvm/DebugInfo/DWARF/DWARFDie.h"
10#include "llvm/ADT/None.h"
11#include "llvm/ADT/Optional.h"
12#include "llvm/ADT/SmallSet.h"
13#include "llvm/ADT/StringRef.h"
14#include "llvm/BinaryFormat/Dwarf.h"
15#include "llvm/DebugInfo/DWARF/DWARFAbbreviationDeclaration.h"
16#include "llvm/DebugInfo/DWARF/DWARFContext.h"
17#include "llvm/DebugInfo/DWARF/DWARFDebugRangeList.h"
18#include "llvm/DebugInfo/DWARF/DWARFExpression.h"
19#include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
20#include "llvm/DebugInfo/DWARF/DWARFUnit.h"
21#include "llvm/Object/ObjectFile.h"
22#include "llvm/Support/DataExtractor.h"
23#include "llvm/Support/Format.h"
24#include "llvm/Support/FormatVariadic.h"
25#include "llvm/Support/MathExtras.h"
26#include "llvm/Support/WithColor.h"
27#include "llvm/Support/raw_ostream.h"
28#include <algorithm>
29#include <cassert>
30#include <cinttypes>
31#include <cstdint>
32#include <string>
33#include <utility>
34
35using namespace llvm;
36using namespace dwarf;
37using namespace object;
38
39static void dumpApplePropertyAttribute(raw_ostream &OS, uint64_t Val) {
40 OS << " (";
41 do {
42 uint64_t Shift = countTrailingZeros(Val);
43 assert(Shift < 64 && "undefined behavior")((Shift < 64 && "undefined behavior") ? static_cast
<void> (0) : __assert_fail ("Shift < 64 && \"undefined behavior\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/DebugInfo/DWARF/DWARFDie.cpp"
, 43, __PRETTY_FUNCTION__));
44 uint64_t Bit = 1ULL << Shift;
45 auto PropName = ApplePropertyString(Bit);
46 if (!PropName.empty())
47 OS << PropName;
48 else
49 OS << format("DW_APPLE_PROPERTY_0x%" PRIx64"l" "x", Bit);
50 if (!(Val ^= Bit))
51 break;
52 OS << ", ";
53 } while (true);
54 OS << ")";
55}
56
57static void dumpRanges(const DWARFObject &Obj, raw_ostream &OS,
58 const DWARFAddressRangesVector &Ranges,
59 unsigned AddressSize, unsigned Indent,
60 const DIDumpOptions &DumpOpts) {
61 if (!DumpOpts.ShowAddresses)
62 return;
63
64 ArrayRef<SectionName> SectionNames;
65 if (DumpOpts.Verbose)
66 SectionNames = Obj.getSectionNames();
67
68 for (const DWARFAddressRange &R : Ranges) {
69 OS << '\n';
70 OS.indent(Indent);
71 R.dump(OS, AddressSize);
72
73 DWARFFormValue::dumpAddressSection(Obj, OS, DumpOpts, R.SectionIndex);
74 }
75}
76
77static void dumpLocation(raw_ostream &OS, DWARFFormValue &FormValue,
78 DWARFUnit *U, unsigned Indent,
79 DIDumpOptions DumpOpts) {
80 DWARFContext &Ctx = U->getContext();
81 const DWARFObject &Obj = Ctx.getDWARFObj();
82 const MCRegisterInfo *MRI = Ctx.getRegisterInfo();
83 if (FormValue.isFormClass(DWARFFormValue::FC_Block) ||
84 FormValue.isFormClass(DWARFFormValue::FC_Exprloc)) {
85 ArrayRef<uint8_t> Expr = *FormValue.getAsBlock();
86 DataExtractor Data(StringRef((const char *)Expr.data(), Expr.size()),
87 Ctx.isLittleEndian(), 0);
88 DWARFExpression(Data, U->getVersion(), U->getAddressByteSize())
89 .print(OS, MRI, U);
90 return;
91 }
92
93 FormValue.dump(OS, DumpOpts);
94 if (FormValue.isFormClass(DWARFFormValue::FC_SectionOffset)) {
95 uint32_t Offset = *FormValue.getAsSectionOffset();
96 if (!U->isDWOUnit() && !U->getLocSection()->Data.empty()) {
97 DWARFDebugLoc DebugLoc;
98 DWARFDataExtractor Data(Obj, *U->getLocSection(), Ctx.isLittleEndian(),
99 Obj.getAddressSize());
100 auto LL = DebugLoc.parseOneLocationList(Data, &Offset);
101 if (LL) {
102 uint64_t BaseAddr = 0;
103 if (Optional<object::SectionedAddress> BA = U->getBaseAddress())
104 BaseAddr = BA->Address;
105 LL->dump(OS, Ctx.isLittleEndian(), Obj.getAddressSize(), MRI, U,
106 BaseAddr, Indent);
107 } else
108 OS << "error extracting location list.";
109 return;
110 }
111
112 bool UseLocLists = !U->isDWOUnit();
113 StringRef LoclistsSectionData =
114 UseLocLists ? Obj.getLoclistsSection().Data : U->getLocSectionData();
115
116 if (!LoclistsSectionData.empty()) {
117 DataExtractor Data(LoclistsSectionData, Ctx.isLittleEndian(),
118 Obj.getAddressSize());
119
120 // Old-style location list were used in DWARF v4 (.debug_loc.dwo section).
121 // Modern locations list (.debug_loclists) are used starting from v5.
122 // Ideally we should take the version from the .debug_loclists section
123 // header, but using CU's version for simplicity.
124 auto LL = DWARFDebugLoclists::parseOneLocationList(
125 Data, &Offset, UseLocLists ? U->getVersion() : 4);
126
127 uint64_t BaseAddr = 0;
128 if (Optional<object::SectionedAddress> BA = U->getBaseAddress())
129 BaseAddr = BA->Address;
130
131 if (LL)
132 LL->dump(OS, BaseAddr, Ctx.isLittleEndian(), Obj.getAddressSize(), MRI,
133 U, Indent);
134 else
135 OS << "error extracting location list.";
136 }
137 }
138}
139
140/// Dump the name encoded in the type tag.
141static void dumpTypeTagName(raw_ostream &OS, dwarf::Tag T) {
142 StringRef TagStr = TagString(T);
143 if (!TagStr.startswith("DW_TAG_") || !TagStr.endswith("_type"))
144 return;
145 OS << TagStr.substr(7, TagStr.size() - 12) << " ";
146}
147
148static void dumpArrayType(raw_ostream &OS, const DWARFDie &D) {
149 Optional<uint64_t> Bound;
150 for (const DWARFDie &C : D.children())
151 if (C.getTag() == DW_TAG_subrange_type) {
152 Optional<uint64_t> LB;
153 Optional<uint64_t> Count;
154 Optional<uint64_t> UB;
155 Optional<unsigned> DefaultLB;
156 if (Optional<DWARFFormValue> L = C.find(DW_AT_lower_bound))
157 LB = L->getAsUnsignedConstant();
158 if (Optional<DWARFFormValue> CountV = C.find(DW_AT_count))
159 Count = CountV->getAsUnsignedConstant();
160 if (Optional<DWARFFormValue> UpperV = C.find(DW_AT_upper_bound))
161 UB = UpperV->getAsUnsignedConstant();
162 if (Optional<DWARFFormValue> LV =
163 D.getDwarfUnit()->getUnitDIE().find(DW_AT_language))
164 if (Optional<uint64_t> LC = LV->getAsUnsignedConstant())
165 if ((DefaultLB =
166 LanguageLowerBound(static_cast<dwarf::SourceLanguage>(*LC))))
167 if (LB && *LB == *DefaultLB)
168 LB = None;
169 if (!LB && !Count && !UB)
170 OS << "[]";
171 else if (!LB && (Count || UB) && DefaultLB)
172 OS << '[' << (Count ? *Count : *UB - *DefaultLB + 1) << ']';
173 else {
174 OS << "[[";
175 if (LB)
176 OS << *LB;
177 else
178 OS << '?';
179 OS << ", ";
180 if (Count)
181 if (LB)
182 OS << *LB + *Count;
183 else
184 OS << "? + " << *Count;
185 else if (UB)
186 OS << *UB + 1;
187 else
188 OS << '?';
189 OS << ")]";
190 }
191 }
192}
193
194/// Recursively dump the DIE type name when applicable.
195static void dumpTypeName(raw_ostream &OS, const DWARFDie &D) {
196 if (!D.isValid())
197 return;
198
199 if (const char *Name = D.getName(DINameKind::LinkageName)) {
200 OS << Name;
201 return;
202 }
203
204 // FIXME: We should have pretty printers per language. Currently we print
205 // everything as if it was C++ and fall back to the TAG type name.
206 const dwarf::Tag T = D.getTag();
207 switch (T) {
208 case DW_TAG_array_type:
209 case DW_TAG_pointer_type:
210 case DW_TAG_ptr_to_member_type:
211 case DW_TAG_reference_type:
212 case DW_TAG_rvalue_reference_type:
213 case DW_TAG_subroutine_type:
214 break;
215 default:
216 dumpTypeTagName(OS, T);
217 }
218
219 // Follow the DW_AT_type if possible.
220 DWARFDie TypeDie = D.getAttributeValueAsReferencedDie(DW_AT_type);
221 dumpTypeName(OS, TypeDie);
222
223 switch (T) {
224 case DW_TAG_subroutine_type: {
225 if (!TypeDie)
226 OS << "void";
227 OS << '(';
228 bool First = true;
229 for (const DWARFDie &C : D.children()) {
230 if (C.getTag() == DW_TAG_formal_parameter) {
231 if (!First)
232 OS << ", ";
233 First = false;
234 dumpTypeName(OS, C.getAttributeValueAsReferencedDie(DW_AT_type));
235 }
236 }
237 OS << ')';
238 break;
239 }
240 case DW_TAG_array_type: {
241 dumpArrayType(OS, D);
242 break;
243 }
244 case DW_TAG_pointer_type:
245 OS << '*';
246 break;
247 case DW_TAG_ptr_to_member_type:
248 if (DWARFDie Cont =
249 D.getAttributeValueAsReferencedDie(DW_AT_containing_type)) {
250 dumpTypeName(OS << ' ', Cont);
251 OS << "::";
252 }
253 OS << '*';
254 break;
255 case DW_TAG_reference_type:
256 OS << '&';
257 break;
258 case DW_TAG_rvalue_reference_type:
259 OS << "&&";
260 break;
261 default:
262 break;
263 }
264}
265
266static void dumpAttribute(raw_ostream &OS, const DWARFDie &Die,
267 uint32_t *OffsetPtr, dwarf::Attribute Attr,
268 dwarf::Form Form, unsigned Indent,
269 DIDumpOptions DumpOpts) {
270 if (!Die.isValid())
38
←
Assuming the condition is false
→
39
←
Taking false branch
→
271 return;
272 const char BaseIndent[] = " ";
273 OS << BaseIndent;
274 OS.indent(Indent + 2);
275 WithColor(OS, HighlightColor::Attribute) << formatv("{0}", Attr);
276
277 if (DumpOpts.Verbose || DumpOpts.ShowForm)
40
←
Assuming the condition is false
→
41
←
Taking false branch
→
278 OS << formatv(" [{0}]", Form);
279
280 DWARFUnit *U = Die.getDwarfUnit();
281 DWARFFormValue FormValue = DWARFFormValue::createFromUnit(Form, U, OffsetPtr);
282
283 OS << "\t(";
284
285 StringRef Name;
286 std::string File;
287 auto Color = HighlightColor::Enumerator;
288 if (Attr == DW_AT_decl_file || Attr == DW_AT_call_file) {
42
←
Assuming 'Attr' is not equal to DW_AT_decl_file
→
43
←
Assuming 'Attr' is not equal to DW_AT_call_file
→
44
←
Taking false branch
→
289 Color = HighlightColor::String;
290 if (const auto *LT = U->getContext().getLineTableForUnit(U))
291 if (LT->getFileNameByIndex(
292 FormValue.getAsUnsignedConstant().getValue(),
293 U->getCompilationDir(),
294 DILineInfoSpecifier::FileLineInfoKind::AbsoluteFilePath, File)) {
295 File = '"' + File + '"';
296 Name = File;
297 }
298 } else if (Optional<uint64_t> Val = FormValue.getAsUnsignedConstant())
45
←
Assuming the condition is false
→
46
←
Taking false branch
→
299 Name = AttributeValueString(Attr, *Val);
300
301 if (!Name.empty())
47
←
Assuming the condition is false
→
48
←
Taking false branch
→
302 WithColor(OS, Color) << Name;
303 else if (Attr == DW_AT_decl_line || Attr == DW_AT_call_line)
49
←
Assuming 'Attr' is not equal to DW_AT_decl_line
→
50
←
Assuming 'Attr' is not equal to DW_AT_call_line
→
51
←
Taking false branch
→
304 OS << *FormValue.getAsUnsignedConstant();
305 else if (Attr == DW_AT_high_pc && !DumpOpts.ShowForm && !DumpOpts.Verbose &&
52
←
Assuming 'Attr' is not equal to DW_AT_high_pc
→
53
←
Taking false branch
→
306 FormValue.getAsUnsignedConstant()) {
307 if (DumpOpts.ShowAddresses) {
308 // Print the actual address rather than the offset.
309 uint64_t LowPC, HighPC, Index;
310 if (Die.getLowAndHighPC(LowPC, HighPC, Index))
311 OS << format("0x%016" PRIx64"l" "x", HighPC);
312 else
313 FormValue.dump(OS, DumpOpts);
314 }
315 } else if (DWARFAttribute::mayHaveLocationDescription(Attr))
54
←
Taking false branch
→
316 dumpLocation(OS, FormValue, U, sizeof(BaseIndent) + Indent + 4, DumpOpts);
317 else
318 FormValue.dump(OS, DumpOpts);
319
320 std::string Space = DumpOpts.ShowAddresses ? " " : "";
55
←
'?' condition is false
→
321
322 // We have dumped the attribute raw value. For some attributes
323 // having both the raw value and the pretty-printed value is
324 // interesting. These attributes are handled below.
325 if (Attr == DW_AT_specification || Attr == DW_AT_abstract_origin) {
56
←
Assuming 'Attr' is not equal to DW_AT_specification
→
57
←
Assuming 'Attr' is not equal to DW_AT_abstract_origin
→
58
←
Taking false branch
→
326 if (const char *Name =
327 Die.getAttributeValueAsReferencedDie(FormValue).getName(
328 DINameKind::LinkageName))
329 OS << Space << "\"" << Name << '\"';
330 } else if (Attr == DW_AT_type) {
59
←
Assuming 'Attr' is not equal to DW_AT_type
→
60
←
Taking false branch
→
331 OS << Space << "\"";
332 dumpTypeName(OS, Die.getAttributeValueAsReferencedDie(FormValue));
333 OS << '"';
334 } else if (Attr == DW_AT_APPLE_property_attribute) {
61
←
Assuming 'Attr' is not equal to DW_AT_APPLE_property_attribute
→
62
←
Taking false branch
→
335 if (Optional<uint64_t> OptVal = FormValue.getAsUnsignedConstant())
336 dumpApplePropertyAttribute(OS, *OptVal);
337 } else if (Attr == DW_AT_ranges) {
63
←
Assuming 'Attr' is equal to DW_AT_ranges
→
64
←
Taking true branch
→
338 const DWARFObject &Obj = Die.getDwarfUnit()->getContext().getDWARFObj();
339 // For DW_FORM_rnglistx we need to dump the offset separately, since
340 // we have only dumped the index so far.
341 if (FormValue.getForm() == DW_FORM_rnglistx)
65
←
Assuming the condition is false
→
66
←
Taking false branch
→
342 if (auto RangeListOffset =
343 U->getRnglistOffset(*FormValue.getAsSectionOffset())) {
344 DWARFFormValue FV = DWARFFormValue::createFromUValue(
345 dwarf::DW_FORM_sec_offset, *RangeListOffset);
346 FV.dump(OS, DumpOpts);
347 }
348 if (auto RangesOrError = Die.getAddressRanges())
67
←
Taking false branch
→
349 dumpRanges(Obj, OS, RangesOrError.get(), U->getAddressByteSize(),
350 sizeof(BaseIndent) + Indent + 4, DumpOpts);
351 else
352 WithColor::error() << "decoding address ranges: "
353 << toString(RangesOrError.takeError()) << '\n';
68
←
Calling 'toString'
→
354 }
355
356 OS << ")\n";
357}
358
359bool DWARFDie::isSubprogramDIE() const { return getTag() == DW_TAG_subprogram; }
360
361bool DWARFDie::isSubroutineDIE() const {
362 auto Tag = getTag();
363 return Tag == DW_TAG_subprogram || Tag == DW_TAG_inlined_subroutine;
364}
365
366Optional<DWARFFormValue> DWARFDie::find(dwarf::Attribute Attr) const {
367 if (!isValid())
368 return None;
369 auto AbbrevDecl = getAbbreviationDeclarationPtr();
370 if (AbbrevDecl)
371 return AbbrevDecl->getAttributeValue(getOffset(), Attr, *U);
372 return None;
373}
374
375Optional<DWARFFormValue>
376DWARFDie::find(ArrayRef<dwarf::Attribute> Attrs) const {
377 if (!isValid())
378 return None;
379 auto AbbrevDecl = getAbbreviationDeclarationPtr();
380 if (AbbrevDecl) {
381 for (auto Attr : Attrs) {
382 if (auto Value = AbbrevDecl->getAttributeValue(getOffset(), Attr, *U))
383 return Value;
384 }
385 }
386 return None;
387}
388
389Optional<DWARFFormValue>
390DWARFDie::findRecursively(ArrayRef<dwarf::Attribute> Attrs) const {
391 std::vector<DWARFDie> Worklist;
392 Worklist.push_back(*this);
393
394 // Keep track if DIEs already seen to prevent infinite recursion.
395 // Empirically we rarely see a depth of more than 3 when dealing with valid
396 // DWARF. This corresponds to following the DW_AT_abstract_origin and
397 // DW_AT_specification just once.
398 SmallSet<DWARFDie, 3> Seen;
399 Seen.insert(*this);
400
401 while (!Worklist.empty()) {
402 DWARFDie Die = Worklist.back();
403 Worklist.pop_back();
404
405 if (!Die.isValid())
406 continue;
407
408 if (auto Value = Die.find(Attrs))
409 return Value;
410
411 if (auto D = Die.getAttributeValueAsReferencedDie(DW_AT_abstract_origin))
412 if (Seen.insert(D).second)
413 Worklist.push_back(D);
414
415 if (auto D = Die.getAttributeValueAsReferencedDie(DW_AT_specification))
416 if (Seen.insert(D).second)
417 Worklist.push_back(D);
418 }
419
420 return None;
421}
422
423DWARFDie
424DWARFDie::getAttributeValueAsReferencedDie(dwarf::Attribute Attr) const {
425 if (Optional<DWARFFormValue> F = find(Attr))
426 return getAttributeValueAsReferencedDie(*F);
427 return DWARFDie();
428}
429
430DWARFDie
431DWARFDie::getAttributeValueAsReferencedDie(const DWARFFormValue &V) const {
432 if (auto SpecRef = V.getAsRelativeReference()) {
433 if (SpecRef->Unit)
434 return SpecRef->Unit->getDIEForOffset(SpecRef->Unit->getOffset() + SpecRef->Offset);
435 if (auto SpecUnit = U->getUnitVector().getUnitForOffset(SpecRef->Offset))
436 return SpecUnit->getDIEForOffset(SpecRef->Offset);
437 }
438 return DWARFDie();
439}
440
441Optional<uint64_t> DWARFDie::getRangesBaseAttribute() const {
442 return toSectionOffset(find({DW_AT_rnglists_base, DW_AT_GNU_ranges_base}));
443}
444
445Optional<uint64_t> DWARFDie::getHighPC(uint64_t LowPC) const {
446 if (auto FormValue = find(DW_AT_high_pc)) {
447 if (auto Address = FormValue->getAsAddress()) {
448 // High PC is an address.
449 return Address;
450 }
451 if (auto Offset = FormValue->getAsUnsignedConstant()) {
452 // High PC is an offset from LowPC.
453 return LowPC + *Offset;
454 }
455 }
456 return None;
457}
458
459bool DWARFDie::getLowAndHighPC(uint64_t &LowPC, uint64_t &HighPC,
460 uint64_t &SectionIndex) const {
461 auto F = find(DW_AT_low_pc);
462 auto LowPcAddr = toSectionedAddress(F);
463 if (!LowPcAddr)
464 return false;
465 if (auto HighPcAddr = getHighPC(LowPcAddr->Address)) {
466 LowPC = LowPcAddr->Address;
467 HighPC = *HighPcAddr;
468 SectionIndex = LowPcAddr->SectionIndex;
469 return true;
470 }
471 return false;
472}
473
474Expected<DWARFAddressRangesVector> DWARFDie::getAddressRanges() const {
475 if (isNULL())
476 return DWARFAddressRangesVector();
477 // Single range specified by low/high PC.
478 uint64_t LowPC, HighPC, Index;
479 if (getLowAndHighPC(LowPC, HighPC, Index))
480 return DWARFAddressRangesVector{{LowPC, HighPC, Index}};
481
482 Optional<DWARFFormValue> Value = find(DW_AT_ranges);
483 if (Value) {
484 if (Value->getForm() == DW_FORM_rnglistx)
485 return U->findRnglistFromIndex(*Value->getAsSectionOffset());
486 return U->findRnglistFromOffset(*Value->getAsSectionOffset());
487 }
488 return DWARFAddressRangesVector();
489}
490
491void DWARFDie::collectChildrenAddressRanges(
492 DWARFAddressRangesVector &Ranges) const {
493 if (isNULL())
494 return;
495 if (isSubprogramDIE()) {
496 if (auto DIERangesOrError = getAddressRanges())
497 Ranges.insert(Ranges.end(), DIERangesOrError.get().begin(),
498 DIERangesOrError.get().end());
499 else
500 llvm::consumeError(DIERangesOrError.takeError());
501 }
502
503 for (auto Child : children())
504 Child.collectChildrenAddressRanges(Ranges);
505}
506
507bool DWARFDie::addressRangeContainsAddress(const uint64_t Address) const {
508 auto RangesOrError = getAddressRanges();
509 if (!RangesOrError) {
510 llvm::consumeError(RangesOrError.takeError());
511 return false;
512 }
513
514 for (const auto &R : RangesOrError.get())
515 if (R.LowPC <= Address && Address < R.HighPC)
516 return true;
517 return false;
518}
519
520const char *DWARFDie::getSubroutineName(DINameKind Kind) const {
521 if (!isSubroutineDIE())
522 return nullptr;
523 return getName(Kind);
524}
525
526const char *DWARFDie::getName(DINameKind Kind) const {
527 if (!isValid() || Kind == DINameKind::None)
528 return nullptr;
529 // Try to get mangled name only if it was asked for.
530 if (Kind == DINameKind::LinkageName) {
531 if (auto Name = dwarf::toString(
532 findRecursively({DW_AT_MIPS_linkage_name, DW_AT_linkage_name}),
533 nullptr))
534 return Name;
535 }
536 if (auto Name = dwarf::toString(findRecursively(DW_AT_name), nullptr))
537 return Name;
538 return nullptr;
539}
540
541uint64_t DWARFDie::getDeclLine() const {
542 return toUnsigned(findRecursively(DW_AT_decl_line), 0);
543}
544
545void DWARFDie::getCallerFrame(uint32_t &CallFile, uint32_t &CallLine,
546 uint32_t &CallColumn,
547 uint32_t &CallDiscriminator) const {
548 CallFile = toUnsigned(find(DW_AT_call_file), 0);
549 CallLine = toUnsigned(find(DW_AT_call_line), 0);
550 CallColumn = toUnsigned(find(DW_AT_call_column), 0);
551 CallDiscriminator = toUnsigned(find(DW_AT_GNU_discriminator), 0);
552}
553
554/// Helper to dump a DIE with all of its parents, but no siblings.
555static unsigned dumpParentChain(DWARFDie Die, raw_ostream &OS, unsigned Indent,
556 DIDumpOptions DumpOpts, unsigned Depth = 0) {
557 if (!Die)
558 return Indent;
559 if (DumpOpts.ParentRecurseDepth > 0 && Depth >= DumpOpts.ParentRecurseDepth)
560 return Indent;
561 Indent = dumpParentChain(Die.getParent(), OS, Indent, DumpOpts, Depth + 1);
562 Die.dump(OS, Indent, DumpOpts);
563 return Indent + 2;
564}
565
566void DWARFDie::dump(raw_ostream &OS, unsigned Indent,
567 DIDumpOptions DumpOpts) const {
568 if (!isValid())
2
←
Assuming the condition is false
→
3
←
Taking false branch
→
22
←
Assuming the condition is false
→
23
←
Taking false branch
→
569 return;
570 DWARFDataExtractor debug_info_data = U->getDebugInfoExtractor();
571 const uint32_t Offset = getOffset();
572 uint32_t offset = Offset;
573 if (DumpOpts.ShowParents) {
4
←
Assuming the condition is false
→
5
←
Taking false branch
→
24
←
Taking false branch
→
574 DIDumpOptions ParentDumpOpts = DumpOpts;
575 ParentDumpOpts.ShowParents = false;
576 ParentDumpOpts.ShowChildren = false;
577 Indent = dumpParentChain(getParent(), OS, Indent, ParentDumpOpts);
578 }
579
580 if (debug_info_data.isValidOffset(offset)) {
6
←
Taking true branch
→
25
←
Taking true branch
→
581 uint32_t abbrCode = debug_info_data.getULEB128(&offset);
582 if (DumpOpts.ShowAddresses)
7
←
Assuming the condition is false
→
8
←
Taking false branch
→
26
←
Assuming the condition is false
→
27
←
Taking false branch
→
583 WithColor(OS, HighlightColor::Address).get()
584 << format("\n0x%8.8x: ", Offset);
585
586 if (abbrCode) {
9
←
Assuming 'abbrCode' is not equal to 0
→
10
←
Taking true branch
→
28
←
Assuming 'abbrCode' is not equal to 0
→
29
←
Taking true branch
→
587 auto AbbrevDecl = getAbbreviationDeclarationPtr();
588 if (AbbrevDecl) {
11
←
Assuming 'AbbrevDecl' is non-null
→
12
←
Taking true branch
→
30
←
Assuming 'AbbrevDecl' is non-null
→
31
←
Taking true branch
→
589 WithColor(OS, HighlightColor::Tag).get().indent(Indent)
590 << formatv("{0}", getTag());
591 if (DumpOpts.Verbose)
13
←
Assuming the condition is false
→
14
←
Taking false branch
→
32
←
Assuming the condition is false
→
33
←
Taking false branch
→
592 OS << format(" [%u] %c", abbrCode,
593 AbbrevDecl->hasChildren() ? '*' : ' ');
594 OS << '\n';
595
596 // Dump all data in the DIE for the attributes.
597 for (const auto &AttrSpec : AbbrevDecl->attributes()) {
15
←
Assuming '__begin4' is equal to '__end4'
→
34
←
Assuming '__begin4' is not equal to '__end4'
→
598 if (AttrSpec.Form == DW_FORM_implicit_const) {
35
←
Assuming the condition is false
→
36
←
Taking false branch
→
599 // We are dumping .debug_info section ,
600 // implicit_const attribute values are not really stored here,
601 // but in .debug_abbrev section. So we just skip such attrs.
602 continue;
603 }
604 dumpAttribute(OS, *this, &offset, AttrSpec.Attr, AttrSpec.Form,
37
←
Calling 'dumpAttribute'
→
605 Indent, DumpOpts);
606 }
607
608 DWARFDie child = getFirstChild();
609 if (DumpOpts.ShowChildren && DumpOpts.ChildRecurseDepth > 0 && child) {
16
←
Assuming the condition is true
→
17
←
Assuming the condition is true
→
18
←
Assuming the condition is true
→
19
←
Taking true branch
→
610 DumpOpts.ChildRecurseDepth--;
611 DIDumpOptions ChildDumpOpts = DumpOpts;
612 ChildDumpOpts.ShowParents = false;
613 while (child) {
20
←
Loop condition is true. Entering loop body
→
614 child.dump(OS, Indent + 2, ChildDumpOpts);
21
←
Calling 'DWARFDie::dump'
→
615 child = child.getSibling();
616 }
617 }
618 } else {
619 OS << "Abbreviation code not found in 'debug_abbrev' class for code: "
620 << abbrCode << '\n';
621 }
622 } else {
623 OS.indent(Indent) << "NULL\n";
624 }
625 }
626}
627
628LLVM_DUMP_METHOD__attribute__((noinline)) __attribute__((__used__)) void DWARFDie::dump() const { dump(llvm::errs(), 0); }
1
Calling 'DWARFDie::dump'
→
629
630DWARFDie DWARFDie::getParent() const {
631 if (isValid())
632 return U->getParent(Die);
633 return DWARFDie();
634}
635
636DWARFDie DWARFDie::getSibling() const {
637 if (isValid())
638 return U->getSibling(Die);
639 return DWARFDie();
640}
641
642DWARFDie DWARFDie::getPreviousSibling() const {
643 if (isValid())
644 return U->getPreviousSibling(Die);
645 return DWARFDie();
646}
647
648DWARFDie DWARFDie::getFirstChild() const {
649 if (isValid())
650 return U->getFirstChild(Die);
651 return DWARFDie();
652}
653
654DWARFDie DWARFDie::getLastChild() const {
655 if (isValid())
656 return U->getLastChild(Die);
657 return DWARFDie();
658}
659
660iterator_range<DWARFDie::attribute_iterator> DWARFDie::attributes() const {
661 return make_range(attribute_iterator(*this, false),
662 attribute_iterator(*this, true));
663}
664
665DWARFDie::attribute_iterator::attribute_iterator(DWARFDie D, bool End)
666 : Die(D), AttrValue(0), Index(0) {
667 auto AbbrDecl = Die.getAbbreviationDeclarationPtr();
668 assert(AbbrDecl && "Must have abbreviation declaration")((AbbrDecl && "Must have abbreviation declaration") ?
static_cast<void> (0) : __assert_fail ("AbbrDecl && \"Must have abbreviation declaration\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/DebugInfo/DWARF/DWARFDie.cpp"
, 668, __PRETTY_FUNCTION__));
669 if (End) {
670 // This is the end iterator so we set the index to the attribute count.
671 Index = AbbrDecl->getNumAttributes();
672 } else {
673 // This is the begin iterator so we extract the value for this->Index.
674 AttrValue.Offset = D.getOffset() + AbbrDecl->getCodeByteSize();
675 updateForIndex(*AbbrDecl, 0);
676 }
677}
678
679void DWARFDie::attribute_iterator::updateForIndex(
680 const DWARFAbbreviationDeclaration &AbbrDecl, uint32_t I) {
681 Index = I;
682 // AbbrDecl must be valid before calling this function.
683 auto NumAttrs = AbbrDecl.getNumAttributes();
684 if (Index < NumAttrs) {
685 AttrValue.Attr = AbbrDecl.getAttrByIndex(Index);
686 // Add the previous byte size of any previous attribute value.
687 AttrValue.Offset += AttrValue.ByteSize;
688 uint32_t ParseOffset = AttrValue.Offset;
689 auto U = Die.getDwarfUnit();
690 assert(U && "Die must have valid DWARF unit")((U && "Die must have valid DWARF unit") ? static_cast
<void> (0) : __assert_fail ("U && \"Die must have valid DWARF unit\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/DebugInfo/DWARF/DWARFDie.cpp"
, 690, __PRETTY_FUNCTION__));
691 AttrValue.Value = DWARFFormValue::createFromUnit(
692 AbbrDecl.getFormByIndex(Index), U, &ParseOffset);
693 AttrValue.ByteSize = ParseOffset - AttrValue.Offset;
694 } else {
695 assert(Index == NumAttrs && "Indexes should be [0, NumAttrs) only")((Index == NumAttrs && "Indexes should be [0, NumAttrs) only"
) ? static_cast<void> (0) : __assert_fail ("Index == NumAttrs && \"Indexes should be [0, NumAttrs) only\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/DebugInfo/DWARF/DWARFDie.cpp"
, 695, __PRETTY_FUNCTION__));
696 AttrValue.clear();
697 }
698}
699
700DWARFDie::attribute_iterator &DWARFDie::attribute_iterator::operator++() {
701 if (auto AbbrDecl = Die.getAbbreviationDeclarationPtr())
702 updateForIndex(*AbbrDecl, Index + 1);
703 return *this;
704}
705
706bool DWARFAttribute::mayHaveLocationDescription(dwarf::Attribute Attr) {
707 switch (Attr) {
708 // From the DWARF v5 specification.
709 case DW_AT_location:
710 case DW_AT_byte_size:
711 case DW_AT_bit_size:
712 case DW_AT_string_length:
713 case DW_AT_lower_bound:
714 case DW_AT_return_addr:
715 case DW_AT_bit_stride:
716 case DW_AT_upper_bound:
717 case DW_AT_count:
718 case DW_AT_data_member_location:
719 case DW_AT_frame_base:
720 case DW_AT_segment:
721 case DW_AT_static_link:
722 case DW_AT_use_location:
723 case DW_AT_vtable_elem_location:
724 case DW_AT_allocated:
725 case DW_AT_associated:
726 case DW_AT_byte_stride:
727 case DW_AT_rank:
728 case DW_AT_call_value:
729 case DW_AT_call_origin:
730 case DW_AT_call_target:
731 case DW_AT_call_target_clobbered:
732 case DW_AT_call_data_location:
733 case DW_AT_call_data_value:
734 // Extensions.
735 case DW_AT_GNU_call_site_value:
736 return true;
737 default:
738 return false;
739 }
740}
←

/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h

1//===- llvm/Support/Error.h - Recoverable error handling --------*- C++ -*-===//
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 defines an API used to report recoverable errors.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_SUPPORT_ERROR_H
14#define LLVM_SUPPORT_ERROR_H
15
16#include "llvm-c/Error.h"
17#include "llvm/ADT/STLExtras.h"
18#include "llvm/ADT/SmallVector.h"
19#include "llvm/ADT/StringExtras.h"
20#include "llvm/ADT/Twine.h"
21#include "llvm/Config/abi-breaking.h"
22#include "llvm/Support/AlignOf.h"
23#include "llvm/Support/Compiler.h"
24#include "llvm/Support/Debug.h"
25#include "llvm/Support/ErrorHandling.h"
26#include "llvm/Support/ErrorOr.h"
27#include "llvm/Support/Format.h"
28#include "llvm/Support/raw_ostream.h"
29#include <algorithm>
30#include <cassert>
31#include <cstdint>
32#include <cstdlib>
33#include <functional>
34#include <memory>
35#include <new>
36#include <string>
37#include <system_error>
38#include <type_traits>
39#include <utility>
40#include <vector>
41
42namespace llvm {
43
44class ErrorSuccess;
45
46/// Base class for error info classes. Do not extend this directly: Extend
47/// the ErrorInfo template subclass instead.
48class ErrorInfoBase {
49public:
50 virtual ~ErrorInfoBase() = default;
51
52 /// Print an error message to an output stream.
53 virtual void log(raw_ostream &OS) const = 0;
54
55 /// Return the error message as a string.
56 virtual std::string message() const {
57 std::string Msg;
58 raw_string_ostream OS(Msg);
59 log(OS);
60 return OS.str();
61 }
62
63 /// Convert this error to a std::error_code.
64 ///
65 /// This is a temporary crutch to enable interaction with code still
66 /// using std::error_code. It will be removed in the future.
67 virtual std::error_code convertToErrorCode() const = 0;
68
69 // Returns the class ID for this type.
70 static const void *classID() { return &ID; }
71
72 // Returns the class ID for the dynamic type of this ErrorInfoBase instance.
73 virtual const void *dynamicClassID() const = 0;
74
75 // Check whether this instance is a subclass of the class identified by
76 // ClassID.
77 virtual bool isA(const void *const ClassID) const {
78 return ClassID == classID();
79 }
80
81 // Check whether this instance is a subclass of ErrorInfoT.
82 template <typename ErrorInfoT> bool isA() const {
83 return isA(ErrorInfoT::classID());
84 }
85
86private:
87 virtual void anchor();
88
89 static char ID;
90};
91
92/// Lightweight error class with error context and mandatory checking.
93///
94/// Instances of this class wrap a ErrorInfoBase pointer. Failure states
95/// are represented by setting the pointer to a ErrorInfoBase subclass
96/// instance containing information describing the failure. Success is
97/// represented by a null pointer value.
98///
99/// Instances of Error also contains a 'Checked' flag, which must be set
100/// before the destructor is called, otherwise the destructor will trigger a
101/// runtime error. This enforces at runtime the requirement that all Error
102/// instances be checked or returned to the caller.
103///
104/// There are two ways to set the checked flag, depending on what state the
105/// Error instance is in. For Error instances indicating success, it
106/// is sufficient to invoke the boolean conversion operator. E.g.:
107///
108/// @code{.cpp}
109/// Error foo(<...>);
110///
111/// if (auto E = foo(<...>))
112/// return E; // <- Return E if it is in the error state.
113/// // We have verified that E was in the success state. It can now be safely
114/// // destroyed.
115/// @endcode
116///
117/// A success value *can not* be dropped. For example, just calling 'foo(<...>)'
118/// without testing the return value will raise a runtime error, even if foo
119/// returns success.
120///
121/// For Error instances representing failure, you must use either the
122/// handleErrors or handleAllErrors function with a typed handler. E.g.:
123///
124/// @code{.cpp}
125/// class MyErrorInfo : public ErrorInfo<MyErrorInfo> {
126/// // Custom error info.
127/// };
128///
129/// Error foo(<...>) { return make_error<MyErrorInfo>(...); }
130///
131/// auto E = foo(<...>); // <- foo returns failure with MyErrorInfo.
132/// auto NewE =
133/// handleErrors(E,
134/// [](const MyErrorInfo &M) {
135/// // Deal with the error.
136/// },
137/// [](std::unique_ptr<OtherError> M) -> Error {
138/// if (canHandle(*M)) {
139/// // handle error.
140/// return Error::success();
141/// }
142/// // Couldn't handle this error instance. Pass it up the stack.
143/// return Error(std::move(M));
144/// );
145/// // Note - we must check or return NewE in case any of the handlers
146/// // returned a new error.
147/// @endcode
148///
149/// The handleAllErrors function is identical to handleErrors, except
150/// that it has a void return type, and requires all errors to be handled and
151/// no new errors be returned. It prevents errors (assuming they can all be
152/// handled) from having to be bubbled all the way to the top-level.
153///
154/// *All* Error instances must be checked before destruction, even if
155/// they're moved-assigned or constructed from Success values that have already
156/// been checked. This enforces checking through all levels of the call stack.
157class LLVM_NODISCARD[[clang::warn_unused_result]] Error {
158 // Both ErrorList and FileError need to be able to yank ErrorInfoBase
159 // pointers out of this class to add to the error list.
160 friend class ErrorList;
161 friend class FileError;
162
163 // handleErrors needs to be able to set the Checked flag.
164 template <typename... HandlerTs>
165 friend Error handleErrors(Error E, HandlerTs &&... Handlers);
166
167 // Expected<T> needs to be able to steal the payload when constructed from an
168 // error.
169 template <typename T> friend class Expected;
170
171 // wrap needs to be able to steal the payload.
172 friend LLVMErrorRef wrap(Error);
173
174protected:
175 /// Create a success value. Prefer using 'Error::success()' for readability
176 Error() {
177 setPtr(nullptr);
178 setChecked(false);
179 }
180
181public:
182 /// Create a success value.
183 static ErrorSuccess success();
184
185 // Errors are not copy-constructable.
186 Error(const Error &Other) = delete;
187
188 /// Move-construct an error value. The newly constructed error is considered
189 /// unchecked, even if the source error had been checked. The original error
190 /// becomes a checked Success value, regardless of its original state.
191 Error(Error &&Other) {
192 setChecked(true);
193 *this = std::move(Other);
194 }
195
196 /// Create an error value. Prefer using the 'make_error' function, but
197 /// this constructor can be useful when "re-throwing" errors from handlers.
198 Error(std::unique_ptr<ErrorInfoBase> Payload) {
199 setPtr(Payload.release());
200 setChecked(false);
86
←
Potential leak of memory pointed to by 'Payload._M_t._M_head_impl'
201 }
202
203 // Errors are not copy-assignable.
204 Error &operator=(const Error &Other) = delete;
205
206 /// Move-assign an error value. The current error must represent success, you
207 /// you cannot overwrite an unhandled error. The current error is then
208 /// considered unchecked. The source error becomes a checked success value,
209 /// regardless of its original state.
210 Error &operator=(Error &&Other) {
211 // Don't allow overwriting of unchecked values.
212 assertIsChecked();
213 setPtr(Other.getPtr());
214
215 // This Error is unchecked, even if the source error was checked.
216 setChecked(false);
217
218 // Null out Other's payload and set its checked bit.
219 Other.setPtr(nullptr);
220 Other.setChecked(true);
221
222 return *this;
223 }
224
225 /// Destroy a Error. Fails with a call to abort() if the error is
226 /// unchecked.
227 ~Error() {
228 assertIsChecked();
229 delete getPtr();
230 }
231
232 /// Bool conversion. Returns true if this Error is in a failure state,
233 /// and false if it is in an accept state. If the error is in a Success state
234 /// it will be considered checked.
235 explicit operator bool() {
236 setChecked(getPtr() == nullptr);
237 return getPtr() != nullptr;
238 }
239
240 /// Check whether one error is a subclass of another.
241 template <typename ErrT> bool isA() const {
242 return getPtr() && getPtr()->isA(ErrT::classID());
243 }
244
245 /// Returns the dynamic class id of this error, or null if this is a success
246 /// value.
247 const void* dynamicClassID() const {
248 if (!getPtr())
249 return nullptr;
250 return getPtr()->dynamicClassID();
251 }
252
253private:
254#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
255 // assertIsChecked() happens very frequently, but under normal circumstances
256 // is supposed to be a no-op. So we want it to be inlined, but having a bunch
257 // of debug prints can cause the function to be too large for inlining. So
258 // it's important that we define this function out of line so that it can't be
259 // inlined.
260 LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn))
261 void fatalUncheckedError() const;
262#endif
263
264 void assertIsChecked() {
265#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
266 if (LLVM_UNLIKELY(!getChecked() || getPtr())__builtin_expect((bool)(!getChecked() || getPtr()), false))
267 fatalUncheckedError();
268#endif
269 }
270
271 ErrorInfoBase *getPtr() const {
272 return reinterpret_cast<ErrorInfoBase*>(
273 reinterpret_cast<uintptr_t>(Payload) &
274 ~static_cast<uintptr_t>(0x1));
275 }
276
277 void setPtr(ErrorInfoBase *EI) {
278#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
279 Payload = reinterpret_cast<ErrorInfoBase*>(
280 (reinterpret_cast<uintptr_t>(EI) &
281 ~static_cast<uintptr_t>(0x1)) |
282 (reinterpret_cast<uintptr_t>(Payload) & 0x1));
283#else
284 Payload = EI;
285#endif
286 }
287
288 bool getChecked() const {
289#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
290 return (reinterpret_cast<uintptr_t>(Payload) & 0x1) == 0;
291#else
292 return true;
293#endif
294 }
295
296 void setChecked(bool V) {
297 Payload = reinterpret_cast<ErrorInfoBase*>(
298 (reinterpret_cast<uintptr_t>(Payload) &
299 ~static_cast<uintptr_t>(0x1)) |
300 (V ? 0 : 1));
301 }
302
303 std::unique_ptr<ErrorInfoBase> takePayload() {
304 std::unique_ptr<ErrorInfoBase> Tmp(getPtr());
305 setPtr(nullptr);
306 setChecked(true);
307 return Tmp;
308 }
309
310 friend raw_ostream &operator<<(raw_ostream &OS, const Error &E) {
311 if (auto P = E.getPtr())
312 P->log(OS);
313 else
314 OS << "success";
315 return OS;
316 }
317
318 ErrorInfoBase *Payload = nullptr;
319};
320
321/// Subclass of Error for the sole purpose of identifying the success path in
322/// the type system. This allows to catch invalid conversion to Expected<T> at
323/// compile time.
324class ErrorSuccess final : public Error {};
325
326inline ErrorSuccess Error::success() { return ErrorSuccess(); }
327
328/// Make a Error instance representing failure using the given error info
329/// type.
330template <typename ErrT, typename... ArgTs> Error make_error(ArgTs &&... Args) {
331 return Error(llvm::make_unique<ErrT>(std::forward<ArgTs>(Args)...));
332}
333
334/// Base class for user error types. Users should declare their error types
335/// like:
336///
337/// class MyError : public ErrorInfo<MyError> {
338/// ....
339/// };
340///
341/// This class provides an implementation of the ErrorInfoBase::kind
342/// method, which is used by the Error RTTI system.
343template <typename ThisErrT, typename ParentErrT = ErrorInfoBase>
344class ErrorInfo : public ParentErrT {
345public:
346 using ParentErrT::ParentErrT; // inherit constructors
347
348 static const void *classID() { return &ThisErrT::ID; }
349
350 const void *dynamicClassID() const override { return &ThisErrT::ID; }
351
352 bool isA(const void *const ClassID) const override {
353 return ClassID == classID() || ParentErrT::isA(ClassID);
354 }
355};
356
357/// Special ErrorInfo subclass representing a list of ErrorInfos.
358/// Instances of this class are constructed by joinError.
359class ErrorList final : public ErrorInfo<ErrorList> {
360 // handleErrors needs to be able to iterate the payload list of an
361 // ErrorList.
362 template <typename... HandlerTs>
363 friend Error handleErrors(Error E, HandlerTs &&... Handlers);
364
365 // joinErrors is implemented in terms of join.
366 friend Error joinErrors(Error, Error);
367
368public:
369 void log(raw_ostream &OS) const override {
370 OS << "Multiple errors:\n";
371 for (auto &ErrPayload : Payloads) {
372 ErrPayload->log(OS);
373 OS << "\n";
374 }
375 }
376
377 std::error_code convertToErrorCode() const override;
378
379 // Used by ErrorInfo::classID.
380 static char ID;
381
382private:
383 ErrorList(std::unique_ptr<ErrorInfoBase> Payload1,
384 std::unique_ptr<ErrorInfoBase> Payload2) {
385 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-9~svn362543/include/llvm/Support/Error.h"
, 386, __PRETTY_FUNCTION__))
386 "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-9~svn362543/include/llvm/Support/Error.h"
, 386, __PRETTY_FUNCTION__));
387 Payloads.push_back(std::move(Payload1));
388 Payloads.push_back(std::move(Payload2));
389 }
390
391 static Error join(Error E1, Error E2) {
392 if (!E1)
76
←
Assuming the condition is false
→
77
←
Taking false branch
→
393 return E2;
394 if (!E2)
78
←
Assuming the condition is false
→
79
←
Taking false branch
→
395 return E1;
396 if (E1.isA<ErrorList>()) {
80
←
Assuming the condition is false
→
81
←
Taking false branch
→
397 auto &E1List = static_cast<ErrorList &>(*E1.getPtr());
398 if (E2.isA<ErrorList>()) {
399 auto E2Payload = E2.takePayload();
400 auto &E2List = static_cast<ErrorList &>(*E2Payload);
401 for (auto &Payload : E2List.Payloads)
402 E1List.Payloads.push_back(std::move(Payload));
403 } else
404 E1List.Payloads.push_back(E2.takePayload());
405
406 return E1;
407 }
408 if (E2.isA<ErrorList>()) {
82
←
Assuming the condition is false
→
83
←
Taking false branch
→
409 auto &E2List = static_cast<ErrorList &>(*E2.getPtr());
410 E2List.Payloads.insert(E2List.Payloads.begin(), E1.takePayload());
411 return E2;
412 }
413 return Error(std::unique_ptr<ErrorList>(
85
←
Calling constructor for 'Error'
→
414 new ErrorList(E1.takePayload(), E2.takePayload())));
84
←
Memory is allocated
→
415 }
416
417 std::vector<std::unique_ptr<ErrorInfoBase>> Payloads;
418};
419
420/// Concatenate errors. The resulting Error is unchecked, and contains the
421/// ErrorInfo(s), if any, contained in E1, followed by the
422/// ErrorInfo(s), if any, contained in E2.
423inline Error joinErrors(Error E1, Error E2) {
424 return ErrorList::join(std::move(E1), std::move(E2));
425}
426
427/// Tagged union holding either a T or a Error.
428///
429/// This class parallels ErrorOr, but replaces error_code with Error. Since
430/// Error cannot be copied, this class replaces getError() with
431/// takeError(). It also adds an bool errorIsA<ErrT>() method for testing the
432/// error class type.
433template <class T> class LLVM_NODISCARD[[clang::warn_unused_result]] Expected {
434 template <class T1> friend class ExpectedAsOutParameter;
435 template <class OtherT> friend class Expected;
436
437 static const bool isRef = std::is_reference<T>::value;
438
439 using wrap = std::reference_wrapper<typename std::remove_reference<T>::type>;
440
441 using error_type = std::unique_ptr<ErrorInfoBase>;
442
443public:
444 using storage_type = typename std::conditional<isRef, wrap, T>::type;
445 using value_type = T;
446
447private:
448 using reference = typename std::remove_reference<T>::type &;
449 using const_reference = const typename std::remove_reference<T>::type &;
450 using pointer = typename std::remove_reference<T>::type *;
451 using const_pointer = const typename std::remove_reference<T>::type *;
452
453public:
454 /// Create an Expected<T> error value from the given Error.
455 Expected(Error Err)
456 : HasError(true)
457#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
458 // Expected is unchecked upon construction in Debug builds.
459 , Unchecked(true)
460#endif
461 {
462 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-9~svn362543/include/llvm/Support/Error.h"
, 462, __PRETTY_FUNCTION__));
463 new (getErrorStorage()) error_type(Err.takePayload());
464 }
465
466 /// Forbid to convert from Error::success() implicitly, this avoids having
467 /// Expected<T> foo() { return Error::success(); } which compiles otherwise
468 /// but triggers the assertion above.
469 Expected(ErrorSuccess) = delete;
470
471 /// Create an Expected<T> success value from the given OtherT value, which
472 /// must be convertible to T.
473 template <typename OtherT>
474 Expected(OtherT &&Val,
475 typename std::enable_if<std::is_convertible<OtherT, T>::value>::type
476 * = nullptr)
477 : HasError(false)
478#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
479 // Expected is unchecked upon construction in Debug builds.
480 , Unchecked(true)
481#endif
482 {
483 new (getStorage()) storage_type(std::forward<OtherT>(Val));
484 }
485
486 /// Move construct an Expected<T> value.
487 Expected(Expected &&Other) { moveConstruct(std::move(Other)); }
488
489 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
490 /// must be convertible to T.
491 template <class OtherT>
492 Expected(Expected<OtherT> &&Other,
493 typename std::enable_if<std::is_convertible<OtherT, T>::value>::type
494 * = nullptr) {
495 moveConstruct(std::move(Other));
496 }
497
498 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
499 /// isn't convertible to T.
500 template <class OtherT>
501 explicit Expected(
502 Expected<OtherT> &&Other,
503 typename std::enable_if<!std::is_convertible<OtherT, T>::value>::type * =
504 nullptr) {
505 moveConstruct(std::move(Other));
506 }
507
508 /// Move-assign from another Expected<T>.
509 Expected &operator=(Expected &&Other) {
510 moveAssign(std::move(Other));
511 return *this;
512 }
513
514 /// Destroy an Expected<T>.
515 ~Expected() {
516 assertIsChecked();
517 if (!HasError)
518 getStorage()->~storage_type();
519 else
520 getErrorStorage()->~error_type();
521 }
522
523 /// Return false if there is an error.
524 explicit operator bool() {
525#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
526 Unchecked = HasError;
527#endif
528 return !HasError;
529 }
530
531 /// Returns a reference to the stored T value.
532 reference get() {
533 assertIsChecked();
534 return *getStorage();
535 }
536
537 /// Returns a const reference to the stored T value.
538 const_reference get() const {
539 assertIsChecked();
540 return const_cast<Expected<T> *>(this)->get();
541 }
542
543 /// Check that this Expected<T> is an error of type ErrT.
544 template <typename ErrT> bool errorIsA() const {
545 return HasError && (*getErrorStorage())->template isA<ErrT>();
546 }
547
548 /// Take ownership of the stored error.
549 /// After calling this the Expected<T> is in an indeterminate state that can
550 /// only be safely destructed. No further calls (beside the destructor) should
551 /// be made on the Expected<T> vaule.
552 Error takeError() {
553#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
554 Unchecked = false;
555#endif
556 return HasError ? Error(std::move(*getErrorStorage())) : Error::success();
557 }
558
559 /// Returns a pointer to the stored T value.
560 pointer operator->() {
561 assertIsChecked();
562 return toPointer(getStorage());
563 }
564
565 /// Returns a const pointer to the stored T value.
566 const_pointer operator->() const {
567 assertIsChecked();
568 return toPointer(getStorage());
569 }
570
571 /// Returns a reference to the stored T value.
572 reference operator*() {
573 assertIsChecked();
574 return *getStorage();
575 }
576
577 /// Returns a const reference to the stored T value.
578 const_reference operator*() const {
579 assertIsChecked();
580 return *getStorage();
581 }
582
583private:
584 template <class T1>
585 static bool compareThisIfSameType(const T1 &a, const T1 &b) {
586 return &a == &b;
587 }
588
589 template <class T1, class T2>
590 static bool compareThisIfSameType(const T1 &a, const T2 &b) {
591 return false;
592 }
593
594 template <class OtherT> void moveConstruct(Expected<OtherT> &&Other) {
595 HasError = Other.HasError;
596#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
597 Unchecked = true;
598 Other.Unchecked = false;
599#endif
600
601 if (!HasError)
602 new (getStorage()) storage_type(std::move(*Other.getStorage()));
603 else
604 new (getErrorStorage()) error_type(std::move(*Other.getErrorStorage()));
605 }
606
607 template <class OtherT> void moveAssign(Expected<OtherT> &&Other) {
608 assertIsChecked();
609
610 if (compareThisIfSameType(*this, Other))
611 return;
612
613 this->~Expected();
614 new (this) Expected(std::move(Other));
615 }
616
617 pointer toPointer(pointer Val) { return Val; }
618
619 const_pointer toPointer(const_pointer Val) const { return Val; }
620
621 pointer toPointer(wrap *Val) { return &Val->get(); }
622
623 const_pointer toPointer(const wrap *Val) const { return &Val->get(); }
624
625 storage_type *getStorage() {
626 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-9~svn362543/include/llvm/Support/Error.h"
, 626, __PRETTY_FUNCTION__));
627 return reinterpret_cast<storage_type *>(TStorage.buffer);
628 }
629
630 const storage_type *getStorage() const {
631 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-9~svn362543/include/llvm/Support/Error.h"
, 631, __PRETTY_FUNCTION__));
632 return reinterpret_cast<const storage_type *>(TStorage.buffer);
633 }
634
635 error_type *getErrorStorage() {
636 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-9~svn362543/include/llvm/Support/Error.h"
, 636, __PRETTY_FUNCTION__));
637 return reinterpret_cast<error_type *>(ErrorStorage.buffer);
638 }
639
640 const error_type *getErrorStorage() const {
641 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-9~svn362543/include/llvm/Support/Error.h"
, 641, __PRETTY_FUNCTION__));
642 return reinterpret_cast<const error_type *>(ErrorStorage.buffer);
643 }
644
645 // Used by ExpectedAsOutParameter to reset the checked flag.
646 void setUnchecked() {
647#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
648 Unchecked = true;
649#endif
650 }
651
652#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
653 LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn))
654 LLVM_ATTRIBUTE_NOINLINE__attribute__((noinline))
655 void fatalUncheckedExpected() const {
656 dbgs() << "Expected<T> must be checked before access or destruction.\n";
657 if (HasError) {
658 dbgs() << "Unchecked Expected<T> contained error:\n";
659 (*getErrorStorage())->log(dbgs());
660 } else
661 dbgs() << "Expected<T> value was in success state. (Note: Expected<T> "
662 "values in success mode must still be checked prior to being "
663 "destroyed).\n";
664 abort();
665 }
666#endif
667
668 void assertIsChecked() {
669#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
670 if (LLVM_UNLIKELY(Unchecked)__builtin_expect((bool)(Unchecked), false))
671 fatalUncheckedExpected();
672#endif
673 }
674
675 union {
676 AlignedCharArrayUnion<storage_type> TStorage;
677 AlignedCharArrayUnion<error_type> ErrorStorage;
678 };
679 bool HasError : 1;
680#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
681 bool Unchecked : 1;
682#endif
683};
684
685/// Report a serious error, calling any installed error handler. See
686/// ErrorHandling.h.
687LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn)) void report_fatal_error(Error Err,
688 bool gen_crash_diag = true);
689
690/// Report a fatal error if Err is a failure value.
691///
692/// This function can be used to wrap calls to fallible functions ONLY when it
693/// is known that the Error will always be a success value. E.g.
694///
695/// @code{.cpp}
696/// // foo only attempts the fallible operation if DoFallibleOperation is
697/// // true. If DoFallibleOperation is false then foo always returns
698/// // Error::success().
699/// Error foo(bool DoFallibleOperation);
700///
701/// cantFail(foo(false));
702/// @endcode
703inline void cantFail(Error Err, const char *Msg = nullptr) {
704 if (Err) {
705 if (!Msg)
706 Msg = "Failure value returned from cantFail wrapped call";
707 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h"
, 707);
708 }
709}
710
711/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
712/// returns the contained value.
713///
714/// This function can be used to wrap calls to fallible functions ONLY when it
715/// is known that the Error will always be a success value. E.g.
716///
717/// @code{.cpp}
718/// // foo only attempts the fallible operation if DoFallibleOperation is
719/// // true. If DoFallibleOperation is false then foo always returns an int.
720/// Expected<int> foo(bool DoFallibleOperation);
721///
722/// int X = cantFail(foo(false));
723/// @endcode
724template <typename T>
725T cantFail(Expected<T> ValOrErr, const char *Msg = nullptr) {
726 if (ValOrErr)
727 return std::move(*ValOrErr);
728 else {
729 if (!Msg)
730 Msg = "Failure value returned from cantFail wrapped call";
731 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h"
, 731);
732 }
733}
734
735/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
736/// returns the contained reference.
737///
738/// This function can be used to wrap calls to fallible functions ONLY when it
739/// is known that the Error will always be a success value. E.g.
740///
741/// @code{.cpp}
742/// // foo only attempts the fallible operation if DoFallibleOperation is
743/// // true. If DoFallibleOperation is false then foo always returns a Bar&.
744/// Expected<Bar&> foo(bool DoFallibleOperation);
745///
746/// Bar &X = cantFail(foo(false));
747/// @endcode
748template <typename T>
749T& cantFail(Expected<T&> ValOrErr, const char *Msg = nullptr) {
750 if (ValOrErr)
751 return *ValOrErr;
752 else {
753 if (!Msg)
754 Msg = "Failure value returned from cantFail wrapped call";
755 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h"
, 755);
756 }
757}
758
759/// Helper for testing applicability of, and applying, handlers for
760/// ErrorInfo types.
761template <typename HandlerT>
762class ErrorHandlerTraits
763 : public ErrorHandlerTraits<decltype(
764 &std::remove_reference<HandlerT>::type::operator())> {};
765
766// Specialization functions of the form 'Error (const ErrT&)'.
767template <typename ErrT> class ErrorHandlerTraits<Error (&)(ErrT &)> {
768public:
769 static bool appliesTo(const ErrorInfoBase &E) {
770 return E.template isA<ErrT>();
771 }
772
773 template <typename HandlerT>
774 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
775 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-9~svn362543/include/llvm/Support/Error.h"
, 775, __PRETTY_FUNCTION__));
776 return H(static_cast<ErrT &>(*E));
777 }
778};
779
780// Specialization functions of the form 'void (const ErrT&)'.
781template <typename ErrT> class ErrorHandlerTraits<void (&)(ErrT &)> {
782public:
783 static bool appliesTo(const ErrorInfoBase &E) {
784 return E.template isA<ErrT>();
785 }
786
787 template <typename HandlerT>
788 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
789 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-9~svn362543/include/llvm/Support/Error.h"
, 789, __PRETTY_FUNCTION__));
790 H(static_cast<ErrT &>(*E));
791 return Error::success();
792 }
793};
794
795/// Specialization for functions of the form 'Error (std::unique_ptr<ErrT>)'.
796template <typename ErrT>
797class ErrorHandlerTraits<Error (&)(std::unique_ptr<ErrT>)> {
798public:
799 static bool appliesTo(const ErrorInfoBase &E) {
800 return E.template isA<ErrT>();
801 }
802
803 template <typename HandlerT>
804 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
805 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-9~svn362543/include/llvm/Support/Error.h"
, 805, __PRETTY_FUNCTION__));
806 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
807 return H(std::move(SubE));
808 }
809};
810
811/// Specialization for functions of the form 'void (std::unique_ptr<ErrT>)'.
812template <typename ErrT>
813class ErrorHandlerTraits<void (&)(std::unique_ptr<ErrT>)> {
814public:
815 static bool appliesTo(const ErrorInfoBase &E) {
816 return E.template isA<ErrT>();
817 }
818
819 template <typename HandlerT>
820 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
821 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-9~svn362543/include/llvm/Support/Error.h"
, 821, __PRETTY_FUNCTION__));
822 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
823 H(std::move(SubE));
824 return Error::success();
825 }
826};
827
828// Specialization for member functions of the form 'RetT (const ErrT&)'.
829template <typename C, typename RetT, typename ErrT>
830class ErrorHandlerTraits<RetT (C::*)(ErrT &)>
831 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
832
833// Specialization for member functions of the form 'RetT (const ErrT&) const'.
834template <typename C, typename RetT, typename ErrT>
835class ErrorHandlerTraits<RetT (C::*)(ErrT &) const>
836 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
837
838// Specialization for member functions of the form 'RetT (const ErrT&)'.
839template <typename C, typename RetT, typename ErrT>
840class ErrorHandlerTraits<RetT (C::*)(const ErrT &)>
841 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
842
843// Specialization for member functions of the form 'RetT (const ErrT&) const'.
844template <typename C, typename RetT, typename ErrT>
845class ErrorHandlerTraits<RetT (C::*)(const ErrT &) const>
846 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
847
848/// Specialization for member functions of the form
849/// 'RetT (std::unique_ptr<ErrT>)'.
850template <typename C, typename RetT, typename ErrT>
851class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>)>
852 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
853
854/// Specialization for member functions of the form
855/// 'RetT (std::unique_ptr<ErrT>) const'.
856template <typename C, typename RetT, typename ErrT>
857class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>) const>
858 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
859
860inline Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload) {
861 return Error(std::move(Payload));
862}
863
864template <typename HandlerT, typename... HandlerTs>
865Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload,
866 HandlerT &&Handler, HandlerTs &&... Handlers) {
867 if (ErrorHandlerTraits<HandlerT>::appliesTo(*Payload))
868 return ErrorHandlerTraits<HandlerT>::apply(std::forward<HandlerT>(Handler),
869 std::move(Payload));
870 return handleErrorImpl(std::move(Payload),
871 std::forward<HandlerTs>(Handlers)...);
872}
873
874/// Pass the ErrorInfo(s) contained in E to their respective handlers. Any
875/// unhandled errors (or Errors returned by handlers) are re-concatenated and
876/// returned.
877/// Because this function returns an error, its result must also be checked
878/// or returned. If you intend to handle all errors use handleAllErrors
879/// (which returns void, and will abort() on unhandled errors) instead.
880template <typename... HandlerTs>
881Error handleErrors(Error E, HandlerTs &&... Hs) {
882 if (!E)
71
←
Assuming the condition is false
→
72
←
Taking false branch
→
883 return Error::success();
884
885 std::unique_ptr<ErrorInfoBase> Payload = E.takePayload();
886
887 if (Payload->isA<ErrorList>()) {
73
←
Assuming the condition is true
→
74
←
Taking true branch
→
888 ErrorList &List = static_cast<ErrorList &>(*Payload);
889 Error R;
890 for (auto &P : List.Payloads)
891 R = ErrorList::join(
75
←
Calling 'ErrorList::join'
→
892 std::move(R),
893 handleErrorImpl(std::move(P), std::forward<HandlerTs>(Hs)...));
894 return R;
895 }
896
897 return handleErrorImpl(std::move(Payload), std::forward<HandlerTs>(Hs)...);
898}
899
900/// Behaves the same as handleErrors, except that by contract all errors
901/// *must* be handled by the given handlers (i.e. there must be no remaining
902/// errors after running the handlers, or llvm_unreachable is called).
903template <typename... HandlerTs>
904void handleAllErrors(Error E, HandlerTs &&... Handlers) {
905 cantFail(handleErrors(std::move(E), std::forward<HandlerTs>(Handlers)...));
70
←
Calling 'handleErrors<(lambda at /build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h:968:33)>'
→
906}
907
908/// Check that E is a non-error, then drop it.
909/// If E is an error, llvm_unreachable will be called.
910inline void handleAllErrors(Error E) {
911 cantFail(std::move(E));
912}
913
914/// Handle any errors (if present) in an Expected<T>, then try a recovery path.
915///
916/// If the incoming value is a success value it is returned unmodified. If it
917/// is a failure value then it the contained error is passed to handleErrors.
918/// If handleErrors is able to handle the error then the RecoveryPath functor
919/// is called to supply the final result. If handleErrors is not able to
920/// handle all errors then the unhandled errors are returned.
921///
922/// This utility enables the follow pattern:
923///
924/// @code{.cpp}
925/// enum FooStrategy { Aggressive, Conservative };
926/// Expected<Foo> foo(FooStrategy S);
927///
928/// auto ResultOrErr =
929/// handleExpected(
930/// foo(Aggressive),
931/// []() { return foo(Conservative); },
932/// [](AggressiveStrategyError&) {
933/// // Implicitly conusme this - we'll recover by using a conservative
934/// // strategy.
935/// });
936///
937/// @endcode
938template <typename T, typename RecoveryFtor, typename... HandlerTs>
939Expected<T> handleExpected(Expected<T> ValOrErr, RecoveryFtor &&RecoveryPath,
940 HandlerTs &&... Handlers) {
941 if (ValOrErr)
942 return ValOrErr;
943
944 if (auto Err = handleErrors(ValOrErr.takeError(),
945 std::forward<HandlerTs>(Handlers)...))
946 return std::move(Err);
947
948 return RecoveryPath();
949}
950
951/// Log all errors (if any) in E to OS. If there are any errors, ErrorBanner
952/// will be printed before the first one is logged. A newline will be printed
953/// after each error.
954///
955/// This function is compatible with the helpers from Support/WithColor.h. You
956/// can pass any of them as the OS. Please consider using them instead of
957/// including 'error: ' in the ErrorBanner.
958///
959/// This is useful in the base level of your program to allow clean termination
960/// (allowing clean deallocation of resources, etc.), while reporting error
961/// information to the user.
962void logAllUnhandledErrors(Error E, raw_ostream &OS, Twine ErrorBanner = {});
963
964/// Write all error messages (if any) in E to a string. The newline character
965/// is used to separate error messages.
966inline std::string toString(Error E) {
967 SmallVector<std::string, 2> Errors;
968 handleAllErrors(std::move(E), [&Errors](const ErrorInfoBase &EI) {
69
←
Calling 'handleAllErrors<(lambda at /build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h:968:33)>'
→
969 Errors.push_back(EI.message());
970 });
971 return join(Errors.begin(), Errors.end(), "\n");
972}
973
974/// Consume a Error without doing anything. This method should be used
975/// only where an error can be considered a reasonable and expected return
976/// value.
977///
978/// Uses of this method are potentially indicative of design problems: If it's
979/// legitimate to do nothing while processing an "error", the error-producer
980/// might be more clearly refactored to return an Optional<T>.
981inline void consumeError(Error Err) {
982 handleAllErrors(std::move(Err), [](const ErrorInfoBase &) {});
983}
984
985/// Helper for converting an Error to a bool.
986///
987/// This method returns true if Err is in an error state, or false if it is
988/// in a success state. Puts Err in a checked state in both cases (unlike
989/// Error::operator bool(), which only does this for success states).
990inline bool errorToBool(Error Err) {
991 bool IsError = static_cast<bool>(Err);
992 if (IsError)
993 consumeError(std::move(Err));
994 return IsError;
995}
996
997/// Helper for Errors used as out-parameters.
998///
999/// This helper is for use with the Error-as-out-parameter idiom, where an error
1000/// is passed to a function or method by reference, rather than being returned.
1001/// In such cases it is helpful to set the checked bit on entry to the function
1002/// so that the error can be written to (unchecked Errors abort on assignment)
1003/// and clear the checked bit on exit so that clients cannot accidentally forget
1004/// to check the result. This helper performs these actions automatically using
1005/// RAII:
1006///
1007/// @code{.cpp}
1008/// Result foo(Error &Err) {
1009/// ErrorAsOutParameter ErrAsOutParam(&Err); // 'Checked' flag set
1010/// // <body of foo>
1011/// // <- 'Checked' flag auto-cleared when ErrAsOutParam is destructed.
1012/// }
1013/// @endcode
1014///
1015/// ErrorAsOutParameter takes an Error* rather than Error& so that it can be
1016/// used with optional Errors (Error pointers that are allowed to be null). If
1017/// ErrorAsOutParameter took an Error reference, an instance would have to be
1018/// created inside every condition that verified that Error was non-null. By
1019/// taking an Error pointer we can just create one instance at the top of the
1020/// function.
1021class ErrorAsOutParameter {
1022public:
1023 ErrorAsOutParameter(Error *Err) : Err(Err) {
1024 // Raise the checked bit if Err is success.
1025 if (Err)
1026 (void)!!*Err;
1027 }
1028
1029 ~ErrorAsOutParameter() {
1030 // Clear the checked bit.
1031 if (Err && !*Err)
1032 *Err = Error::success();
1033 }
1034
1035private:
1036 Error *Err;
1037};
1038
1039/// Helper for Expected<T>s used as out-parameters.
1040///
1041/// See ErrorAsOutParameter.
1042template <typename T>
1043class ExpectedAsOutParameter {
1044public:
1045 ExpectedAsOutParameter(Expected<T> *ValOrErr)
1046 : ValOrErr(ValOrErr) {
1047 if (ValOrErr)
1048 (void)!!*ValOrErr;
1049 }
1050
1051 ~ExpectedAsOutParameter() {
1052 if (ValOrErr)
1053 ValOrErr->setUnchecked();
1054 }
1055
1056private:
1057 Expected<T> *ValOrErr;
1058};
1059
1060/// This class wraps a std::error_code in a Error.
1061///
1062/// This is useful if you're writing an interface that returns a Error
1063/// (or Expected) and you want to call code that still returns
1064/// std::error_codes.
1065class ECError : public ErrorInfo<ECError> {
1066 friend Error errorCodeToError(std::error_code);
1067
1068 virtual void anchor() override;
1069
1070public:
1071 void setErrorCode(std::error_code EC) { this->EC = EC; }
1072 std::error_code convertToErrorCode() const override { return EC; }
1073 void log(raw_ostream &OS) const override { OS << EC.message(); }
1074
1075 // Used by ErrorInfo::classID.
1076 static char ID;
1077
1078protected:
1079 ECError() = default;
1080 ECError(std::error_code EC) : EC(EC) {}
1081
1082 std::error_code EC;
1083};
1084
1085/// The value returned by this function can be returned from convertToErrorCode
1086/// for Error values where no sensible translation to std::error_code exists.
1087/// It should only be used in this situation, and should never be used where a
1088/// sensible conversion to std::error_code is available, as attempts to convert
1089/// to/from this error will result in a fatal error. (i.e. it is a programmatic
1090///error to try to convert such a value).
1091std::error_code inconvertibleErrorCode();
1092
1093/// Helper for converting an std::error_code to a Error.
1094Error errorCodeToError(std::error_code EC);
1095
1096/// Helper for converting an ECError to a std::error_code.
1097///
1098/// This method requires that Err be Error() or an ECError, otherwise it
1099/// will trigger a call to abort().
1100std::error_code errorToErrorCode(Error Err);
1101
1102/// Convert an ErrorOr<T> to an Expected<T>.
1103template <typename T> Expected<T> errorOrToExpected(ErrorOr<T> &&EO) {
1104 if (auto EC = EO.getError())
1105 return errorCodeToError(EC);
1106 return std::move(*EO);
1107}
1108
1109/// Convert an Expected<T> to an ErrorOr<T>.
1110template <typename T> ErrorOr<T> expectedToErrorOr(Expected<T> &&E) {
1111 if (auto Err = E.takeError())
1112 return errorToErrorCode(std::move(Err));
1113 return std::move(*E);
1114}
1115
1116/// This class wraps a string in an Error.
1117///
1118/// StringError is useful in cases where the client is not expected to be able
1119/// to consume the specific error message programmatically (for example, if the
1120/// error message is to be presented to the user).
1121///
1122/// StringError can also be used when additional information is to be printed
1123/// along with a error_code message. Depending on the constructor called, this
1124/// class can either display:
1125/// 1. the error_code message (ECError behavior)
1126/// 2. a string
1127/// 3. the error_code message and a string
1128///
1129/// These behaviors are useful when subtyping is required; for example, when a
1130/// specific library needs an explicit error type. In the example below,
1131/// PDBError is derived from StringError:
1132///
1133/// @code{.cpp}
1134/// Expected<int> foo() {
1135/// return llvm::make_error<PDBError>(pdb_error_code::dia_failed_loading,
1136/// "Additional information");
1137/// }
1138/// @endcode
1139///
1140class StringError : public ErrorInfo<StringError> {
1141public:
1142 static char ID;
1143
1144 // Prints EC + S and converts to EC
1145 StringError(std::error_code EC, const Twine &S = Twine());
1146
1147 // Prints S and converts to EC
1148 StringError(const Twine &S, std::error_code EC);
1149
1150 void log(raw_ostream &OS) const override;
1151 std::error_code convertToErrorCode() const override;
1152
1153 const std::string &getMessage() const { return Msg; }
1154
1155private:
1156 std::string Msg;
1157 std::error_code EC;
1158 const bool PrintMsgOnly = false;
1159};
1160
1161/// Create formatted StringError object.
1162template <typename... Ts>
1163Error createStringError(std::error_code EC, char const *Fmt,
1164 const Ts &... Vals) {
1165 std::string Buffer;
1166 raw_string_ostream Stream(Buffer);
1167 Stream << format(Fmt, Vals...);
1168 return make_error<StringError>(Stream.str(), EC);
1169}
1170
1171Error createStringError(std::error_code EC, char const *Msg);
1172
1173/// This class wraps a filename and another Error.
1174///
1175/// In some cases, an error needs to live along a 'source' name, in order to
1176/// show more detailed information to the user.
1177class FileError final : public ErrorInfo<FileError> {
1178
1179 friend Error createFileError(const Twine &, Error);
1180 friend Error createFileError(const Twine &, size_t, Error);
1181
1182public:
1183 void log(raw_ostream &OS) const override {
1184 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-9~svn362543/include/llvm/Support/Error.h"
, 1184, __PRETTY_FUNCTION__));
1185 OS << "'" << FileName << "': ";
1186 if (Line.hasValue())
1187 OS << "line " << Line.getValue() << ": ";
1188 Err->log(OS);
1189 }
1190
1191 Error takeError() { return Error(std::move(Err)); }
1192
1193 std::error_code convertToErrorCode() const override;
1194
1195 // Used by ErrorInfo::classID.
1196 static char ID;
1197
1198private:
1199 FileError(const Twine &F, Optional<size_t> LineNum,
1200 std::unique_ptr<ErrorInfoBase> E) {
1201 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-9~svn362543/include/llvm/Support/Error.h"
, 1201, __PRETTY_FUNCTION__));
1202 assert(!F.isTriviallyEmpty() &&((!F.isTriviallyEmpty() && "The file name provided to FileError must not be empty."
) ? static_cast<void> (0) : __assert_fail ("!F.isTriviallyEmpty() && \"The file name provided to FileError must not be empty.\""
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h"
, 1203, __PRETTY_FUNCTION__))
1203 "The file name provided to FileError must not be empty.")((!F.isTriviallyEmpty() && "The file name provided to FileError must not be empty."
) ? static_cast<void> (0) : __assert_fail ("!F.isTriviallyEmpty() && \"The file name provided to FileError must not be empty.\""
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h"
, 1203, __PRETTY_FUNCTION__));
1204 FileName = F.str();
1205 Err = std::move(E);
1206 Line = std::move(LineNum);
1207 }
1208
1209 static Error build(const Twine &F, Optional<size_t> Line, Error E) {
1210 return Error(
1211 std::unique_ptr<FileError>(new FileError(F, Line, E.takePayload())));
1212 }
1213
1214 std::string FileName;
1215 Optional<size_t> Line;
1216 std::unique_ptr<ErrorInfoBase> Err;
1217};
1218
1219/// Concatenate a source file path and/or name with an Error. The resulting
1220/// Error is unchecked.
1221inline Error createFileError(const Twine &F, Error E) {
1222 return FileError::build(F, Optional<size_t>(), std::move(E));
1223}
1224
1225/// Concatenate a source file path and/or name with line number and an Error.
1226/// The resulting Error is unchecked.
1227inline Error createFileError(const Twine &F, size_t Line, Error E) {
1228 return FileError::build(F, Optional<size_t>(Line), std::move(E));
1229}
1230
1231/// Concatenate a source file path and/or name with a std::error_code
1232/// to form an Error object.
1233inline Error createFileError(const Twine &F, std::error_code EC) {
1234 return createFileError(F, errorCodeToError(EC));
1235}
1236
1237/// Concatenate a source file path and/or name with line number and
1238/// std::error_code to form an Error object.
1239inline Error createFileError(const Twine &F, size_t Line, std::error_code EC) {
1240 return createFileError(F, Line, errorCodeToError(EC));
1241}
1242
1243Error createFileError(const Twine &F, ErrorSuccess) = delete;
1244
1245/// Helper for check-and-exit error handling.
1246///
1247/// For tool use only. NOT FOR USE IN LIBRARY CODE.
1248///
1249class ExitOnError {
1250public:
1251 /// Create an error on exit helper.
1252 ExitOnError(std::string Banner = "", int DefaultErrorExitCode = 1)
1253 : Banner(std::move(Banner)),
1254 GetExitCode([=](const Error &) { return DefaultErrorExitCode; }) {}
1255
1256 /// Set the banner string for any errors caught by operator().
1257 void setBanner(std::string Banner) { this->Banner = std::move(Banner); }
1258
1259 /// Set the exit-code mapper function.
1260 void setExitCodeMapper(std::function<int(const Error &)> GetExitCode) {
1261 this->GetExitCode = std::move(GetExitCode);
1262 }
1263
1264 /// Check Err. If it's in a failure state log the error(s) and exit.
1265 void operator()(Error Err) const { checkError(std::move(Err)); }
1266
1267 /// Check E. If it's in a success state then return the contained value. If
1268 /// it's in a failure state log the error(s) and exit.
1269 template <typename T> T operator()(Expected<T> &&E) const {
1270 checkError(E.takeError());
1271 return std::move(*E);
1272 }
1273
1274 /// Check E. If it's in a success state then return the contained reference. If
1275 /// it's in a failure state log the error(s) and exit.
1276 template <typename T> T& operator()(Expected<T&> &&E) const {
1277 checkError(E.takeError());
1278 return *E;
1279 }
1280
1281private:
1282 void checkError(Error Err) const {
1283 if (Err) {
1284 int ExitCode = GetExitCode(Err);
1285 logAllUnhandledErrors(std::move(Err), errs(), Banner);
1286 exit(ExitCode);
1287 }
1288 }
1289
1290 std::string Banner;
1291 std::function<int(const Error &)> GetExitCode;
1292};
1293
1294/// Conversion from Error to LLVMErrorRef for C error bindings.
1295inline LLVMErrorRef wrap(Error Err) {
1296 return reinterpret_cast<LLVMErrorRef>(Err.takePayload().release());
1297}
1298
1299/// Conversion from LLVMErrorRef to Error for C error bindings.
1300inline Error unwrap(LLVMErrorRef ErrRef) {
1301 return Error(std::unique_ptr<ErrorInfoBase>(
1302 reinterpret_cast<ErrorInfoBase *>(ErrRef)));
1303}
1304
1305} // end namespace llvm
1306
1307#endif // LLVM_SUPPORT_ERROR_H