Bug Summary

File:include/llvm/Support/Error.h
Warning:line 201, 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-8/lib/clang/8.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-8~svn350071/build-llvm/lib/DebugInfo/DWARF -I /build/llvm-toolchain-snapshot-8~svn350071/lib/DebugInfo/DWARF -I /build/llvm-toolchain-snapshot-8~svn350071/build-llvm/include -I /build/llvm-toolchain-snapshot-8~svn350071/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/8.0.0/include/ -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-8/lib/clang/8.0.0/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-8~svn350071/build-llvm/lib/DebugInfo/DWARF -fdebug-prefix-map=/build/llvm-toolchain-snapshot-8~svn350071=. -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-2018-12-27-042839-1215-1 -x c++ /build/llvm-toolchain-snapshot-8~svn350071/lib/DebugInfo/DWARF/DWARFDie.cpp -faddrsig

/build/llvm-toolchain-snapshot-8~svn350071/lib/DebugInfo/DWARF/DWARFDie.cpp

1//===- DWARFDie.cpp -------------------------------------------------------===//
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#include "llvm/DebugInfo/DWARF/DWARFDie.h"
11#include "llvm/ADT/None.h"
12#include "llvm/ADT/Optional.h"
13#include "llvm/ADT/SmallSet.h"
14#include "llvm/ADT/StringRef.h"
15#include "llvm/BinaryFormat/Dwarf.h"
16#include "llvm/DebugInfo/DWARF/DWARFAbbreviationDeclaration.h"
17#include "llvm/DebugInfo/DWARF/DWARFContext.h"
18#include "llvm/DebugInfo/DWARF/DWARFDebugRangeList.h"
19#include "llvm/DebugInfo/DWARF/DWARFExpression.h"
20#include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
21#include "llvm/DebugInfo/DWARF/DWARFUnit.h"
22#include "llvm/Object/ObjectFile.h"
23#include "llvm/Support/DataExtractor.h"
24#include "llvm/Support/Format.h"
25#include "llvm/Support/FormatVariadic.h"
26#include "llvm/Support/MathExtras.h"
27#include "llvm/Support/WithColor.h"
28#include "llvm/Support/raw_ostream.h"
29#include <algorithm>
30#include <cassert>
31#include <cinttypes>
32#include <cstdint>
33#include <string>
34#include <utility>
35
36using namespace llvm;
37using namespace dwarf;
38using namespace object;
39
40static void dumpApplePropertyAttribute(raw_ostream &OS, uint64_t Val) {
41 OS << " (";
42 do {
43 uint64_t Shift = countTrailingZeros(Val);
44 assert(Shift < 64 && "undefined behavior")((Shift < 64 && "undefined behavior") ? static_cast
<void> (0) : __assert_fail ("Shift < 64 && \"undefined behavior\""
, "/build/llvm-toolchain-snapshot-8~svn350071/lib/DebugInfo/DWARF/DWARFDie.cpp"
, 44, __PRETTY_FUNCTION__))
;
45 uint64_t Bit = 1ULL << Shift;
46 auto PropName = ApplePropertyString(Bit);
47 if (!PropName.empty())
48 OS << PropName;
49 else
50 OS << format("DW_APPLE_PROPERTY_0x%" PRIx64"l" "x", Bit);
51 if (!(Val ^= Bit))
52 break;
53 OS << ", ";
54 } while (true);
55 OS << ")";
56}
57
58static void dumpRanges(const DWARFObject &Obj, raw_ostream &OS,
59 const DWARFAddressRangesVector &Ranges,
60 unsigned AddressSize, unsigned Indent,
61 const DIDumpOptions &DumpOpts) {
62 if (!DumpOpts.ShowAddresses)
63 return;
64
65 ArrayRef<SectionName> SectionNames;
66 if (DumpOpts.Verbose)
67 SectionNames = Obj.getSectionNames();
68
69 for (const DWARFAddressRange &R : Ranges) {
70 OS << '\n';
71 OS.indent(Indent);
72 R.dump(OS, AddressSize);
73
74 DWARFFormValue::dumpAddressSection(Obj, OS, DumpOpts, R.SectionIndex);
75 }
76}
77
78static void dumpLocation(raw_ostream &OS, DWARFFormValue &FormValue,
79 DWARFUnit *U, unsigned Indent,
80 DIDumpOptions DumpOpts) {
81 DWARFContext &Ctx = U->getContext();
82 const DWARFObject &Obj = Ctx.getDWARFObj();
83 const MCRegisterInfo *MRI = Ctx.getRegisterInfo();
84 if (FormValue.isFormClass(DWARFFormValue::FC_Block) ||
85 FormValue.isFormClass(DWARFFormValue::FC_Exprloc)) {
86 ArrayRef<uint8_t> Expr = *FormValue.getAsBlock();
87 DataExtractor Data(StringRef((const char *)Expr.data(), Expr.size()),
88 Ctx.isLittleEndian(), 0);
89 DWARFExpression(Data, U->getVersion(), U->getAddressByteSize())
90 .print(OS, MRI);
91 return;
92 }
93
94 FormValue.dump(OS, DumpOpts);
95 if (FormValue.isFormClass(DWARFFormValue::FC_SectionOffset)) {
96 uint32_t Offset = *FormValue.getAsSectionOffset();
97 if (!U->isDWOUnit() && !U->getLocSection()->Data.empty()) {
98 DWARFDebugLoc DebugLoc;
99 DWARFDataExtractor Data(Obj, *U->getLocSection(), Ctx.isLittleEndian(),
100 Obj.getAddressSize());
101 auto LL = DebugLoc.parseOneLocationList(Data, &Offset);
102 if (LL) {
103 uint64_t BaseAddr = 0;
104 if (Optional<SectionedAddress> BA = U->getBaseAddress())
105 BaseAddr = BA->Address;
106 LL->dump(OS, Ctx.isLittleEndian(), Obj.getAddressSize(), MRI, BaseAddr,
107 Indent);
108 } else
109 OS << "error extracting location list.";
110 return;
111 }
112
113 bool UseLocLists = !U->isDWOUnit();
114 StringRef LoclistsSectionData =
115 UseLocLists ? Obj.getLoclistsSection().Data : U->getLocSectionData();
116
117 if (!LoclistsSectionData.empty()) {
118 DataExtractor Data(LoclistsSectionData, Ctx.isLittleEndian(),
119 Obj.getAddressSize());
120
121 // Old-style location list were used in DWARF v4 (.debug_loc.dwo section).
122 // Modern locations list (.debug_loclists) are used starting from v5.
123 // Ideally we should take the version from the .debug_loclists section
124 // header, but using CU's version for simplicity.
125 auto LL = DWARFDebugLoclists::parseOneLocationList(
126 Data, &Offset, UseLocLists ? U->getVersion() : 4);
127
128 uint64_t BaseAddr = 0;
129 if (Optional<SectionedAddress> BA = U->getBaseAddress())
130 BaseAddr = BA->Address;
131
132 if (LL)
133 LL->dump(OS, BaseAddr, Ctx.isLittleEndian(), Obj.getAddressSize(), MRI,
134 Indent);
135 else
136 OS << "error extracting location list.";
137 }
138 }
139}
140
141/// Dump the name encoded in the type tag.
142static void dumpTypeTagName(raw_ostream &OS, dwarf::Tag T) {
143 StringRef TagStr = TagString(T);
144 if (!TagStr.startswith("DW_TAG_") || !TagStr.endswith("_type"))
145 return;
146 OS << TagStr.substr(7, TagStr.size() - 12) << " ";
147}
148
149static void dumpArrayType(raw_ostream &OS, const DWARFDie &D) {
150 Optional<uint64_t> Bound;
151 for (const DWARFDie &C : D.children())
152 if (C.getTag() == DW_TAG_subrange_type) {
153 Optional<uint64_t> LB;
154 Optional<uint64_t> Count;
155 Optional<uint64_t> UB;
156 Optional<unsigned> DefaultLB;
157 if (Optional<DWARFFormValue> L = C.find(DW_AT_lower_bound))
158 LB = L->getAsUnsignedConstant();
159 if (Optional<DWARFFormValue> CountV = C.find(DW_AT_count))
160 Count = CountV->getAsUnsignedConstant();
161 if (Optional<DWARFFormValue> UpperV = C.find(DW_AT_upper_bound))
162 UB = UpperV->getAsUnsignedConstant();
163 if (Optional<DWARFFormValue> LV =
164 D.getDwarfUnit()->getUnitDIE().find(DW_AT_language))
165 if (Optional<uint64_t> LC = LV->getAsUnsignedConstant())
166 if ((DefaultLB =
167 LanguageLowerBound(static_cast<dwarf::SourceLanguage>(*LC))))
168 if (LB && *LB == *DefaultLB)
169 LB = None;
170 if (!LB && !Count && !UB)
171 OS << "[]";
172 else if (!LB && (Count || UB) && DefaultLB)
173 OS << '[' << (Count ? *Count : *UB - *DefaultLB + 1) << ']';
174 else {
175 OS << "[[";
176 if (LB)
177 OS << *LB;
178 else
179 OS << '?';
180 OS << ", ";
181 if (Count)
182 if (LB)
183 OS << *LB + *Count;
184 else
185 OS << "? + " << *Count;
186 else if (UB)
187 OS << *UB + 1;
188 else
189 OS << '?';
190 OS << ")]";
191 }
192 }
193}
194
195/// Recursively dump the DIE type name when applicable.
196static void dumpTypeName(raw_ostream &OS, const DWARFDie &D) {
197 if (!D.isValid())
198 return;
199
200 if (const char *Name = D.getName(DINameKind::LinkageName)) {
201 OS << Name;
202 return;
203 }
204
205 // FIXME: We should have pretty printers per language. Currently we print
206 // everything as if it was C++ and fall back to the TAG type name.
207 const dwarf::Tag T = D.getTag();
208 switch (T) {
209 case DW_TAG_array_type:
210 case DW_TAG_pointer_type:
211 case DW_TAG_ptr_to_member_type:
212 case DW_TAG_reference_type:
213 case DW_TAG_rvalue_reference_type:
214 case DW_TAG_subroutine_type:
215 break;
216 default:
217 dumpTypeTagName(OS, T);
218 }
219
220 // Follow the DW_AT_type if possible.
221 DWARFDie TypeDie = D.getAttributeValueAsReferencedDie(DW_AT_type);
222 dumpTypeName(OS, TypeDie);
223
224 switch (T) {
225 case DW_TAG_subroutine_type: {
226 if (!TypeDie)
227 OS << "void";
228 OS << '(';
229 bool First = true;
230 for (const DWARFDie &C : D.children()) {
231 if (C.getTag() == DW_TAG_formal_parameter) {
232 if (!First)
233 OS << ", ";
234 First = false;
235 dumpTypeName(OS, C.getAttributeValueAsReferencedDie(DW_AT_type));
236 }
237 }
238 OS << ')';
239 break;
240 }
241 case DW_TAG_array_type: {
242 dumpArrayType(OS, D);
243 break;
244 }
245 case DW_TAG_pointer_type:
246 OS << '*';
247 break;
248 case DW_TAG_ptr_to_member_type:
249 if (DWARFDie Cont =
250 D.getAttributeValueAsReferencedDie(DW_AT_containing_type)) {
251 dumpTypeName(OS << ' ', Cont);
252 OS << "::";
253 }
254 OS << '*';
255 break;
256 case DW_TAG_reference_type:
257 OS << '&';
258 break;
259 case DW_TAG_rvalue_reference_type:
260 OS << "&&";
261 break;
262 default:
263 break;
264 }
265}
266
267static void dumpAttribute(raw_ostream &OS, const DWARFDie &Die,
268 uint32_t *OffsetPtr, dwarf::Attribute Attr,
269 dwarf::Form Form, unsigned Indent,
270 DIDumpOptions DumpOpts) {
271 if (!Die.isValid())
38
Assuming the condition is false
39
Taking false branch
272 return;
273 const char BaseIndent[] = " ";
274 OS << BaseIndent;
275 OS.indent(Indent + 2);
276 WithColor(OS, HighlightColor::Attribute) << formatv("{0}", Attr);
277
278 if (DumpOpts.Verbose || DumpOpts.ShowForm)
40
Assuming the condition is false
41
Taking false branch
279 OS << formatv(" [{0}]", Form);
280
281 DWARFUnit *U = Die.getDwarfUnit();
282 DWARFFormValue formValue(Form);
283
284 if (!formValue.extractValue(U->getDebugInfoExtractor(), OffsetPtr,
42
Assuming the condition is false
43
Taking false branch
285 U->getFormParams(), U))
286 return;
287
288 OS << "\t(";
289
290 StringRef Name;
291 std::string File;
292 auto Color = HighlightColor::Enumerator;
293 if (Attr == DW_AT_decl_file || Attr == DW_AT_call_file) {
44
Assuming 'Attr' is not equal to DW_AT_decl_file
45
Assuming 'Attr' is not equal to DW_AT_call_file
46
Taking false branch
294 Color = HighlightColor::String;
295 if (const auto *LT = U->getContext().getLineTableForUnit(U))
296 if (LT->getFileNameByIndex(
297 formValue.getAsUnsignedConstant().getValue(),
298 U->getCompilationDir(),
299 DILineInfoSpecifier::FileLineInfoKind::AbsoluteFilePath, File)) {
300 File = '"' + File + '"';
301 Name = File;
302 }
303 } else if (Optional<uint64_t> Val = formValue.getAsUnsignedConstant())
47
Assuming the condition is false
48
Taking false branch
304 Name = AttributeValueString(Attr, *Val);
305
306 if (!Name.empty())
49
Assuming the condition is false
50
Taking false branch
307 WithColor(OS, Color) << Name;
308 else if (Attr == DW_AT_decl_line || Attr == DW_AT_call_line)
51
Assuming 'Attr' is not equal to DW_AT_decl_line
52
Assuming 'Attr' is not equal to DW_AT_call_line
53
Taking false branch
309 OS << *formValue.getAsUnsignedConstant();
310 else if (Attr == DW_AT_high_pc && !DumpOpts.ShowForm && !DumpOpts.Verbose &&
54
Assuming 'Attr' is not equal to DW_AT_high_pc
55
Taking false branch
311 formValue.getAsUnsignedConstant()) {
312 if (DumpOpts.ShowAddresses) {
313 // Print the actual address rather than the offset.
314 uint64_t LowPC, HighPC, Index;
315 if (Die.getLowAndHighPC(LowPC, HighPC, Index))
316 OS << format("0x%016" PRIx64"l" "x", HighPC);
317 else
318 formValue.dump(OS, DumpOpts);
319 }
320 } else if (Attr == DW_AT_location || Attr == DW_AT_frame_base ||
56
Assuming 'Attr' is not equal to DW_AT_location
57
Assuming 'Attr' is not equal to DW_AT_frame_base
60
Taking false branch
321 Attr == DW_AT_data_member_location ||
58
Assuming 'Attr' is not equal to DW_AT_data_member_location
322 Attr == DW_AT_GNU_call_site_value)
59
Assuming 'Attr' is not equal to DW_AT_GNU_call_site_value
323 dumpLocation(OS, formValue, U, sizeof(BaseIndent) + Indent + 4, DumpOpts);
324 else
325 formValue.dump(OS, DumpOpts);
326
327 std::string Space = DumpOpts.ShowAddresses ? " " : "";
61
'?' condition is false
328
329 // We have dumped the attribute raw value. For some attributes
330 // having both the raw value and the pretty-printed value is
331 // interesting. These attributes are handled below.
332 if (Attr == DW_AT_specification || Attr == DW_AT_abstract_origin) {
62
Assuming 'Attr' is not equal to DW_AT_specification
63
Assuming 'Attr' is not equal to DW_AT_abstract_origin
64
Taking false branch
333 if (const char *Name =
334 Die.getAttributeValueAsReferencedDie(formValue).getName(
335 DINameKind::LinkageName))
336 OS << Space << "\"" << Name << '\"';
337 } else if (Attr == DW_AT_type) {
65
Assuming 'Attr' is not equal to DW_AT_type
66
Taking false branch
338 OS << Space << "\"";
339 dumpTypeName(OS, Die.getAttributeValueAsReferencedDie(formValue));
340 OS << '"';
341 } else if (Attr == DW_AT_APPLE_property_attribute) {
67
Assuming 'Attr' is not equal to DW_AT_APPLE_property_attribute
68
Taking false branch
342 if (Optional<uint64_t> OptVal = formValue.getAsUnsignedConstant())
343 dumpApplePropertyAttribute(OS, *OptVal);
344 } else if (Attr == DW_AT_ranges) {
69
Assuming 'Attr' is equal to DW_AT_ranges
70
Taking true branch
345 const DWARFObject &Obj = Die.getDwarfUnit()->getContext().getDWARFObj();
346 // For DW_FORM_rnglistx we need to dump the offset separately, since
347 // we have only dumped the index so far.
348 if (formValue.getForm() == DW_FORM_rnglistx)
71
Assuming the condition is false
72
Taking false branch
349 if (auto RangeListOffset =
350 U->getRnglistOffset(*formValue.getAsSectionOffset())) {
351 DWARFFormValue FV(dwarf::DW_FORM_sec_offset);
352 FV.setUValue(*RangeListOffset);
353 FV.dump(OS, DumpOpts);
354 }
355 if (auto RangesOrError = Die.getAddressRanges())
73
Taking false branch
356 dumpRanges(Obj, OS, RangesOrError.get(), U->getAddressByteSize(),
357 sizeof(BaseIndent) + Indent + 4, DumpOpts);
358 else
359 WithColor::error() << "decoding address ranges: "
360 << toString(RangesOrError.takeError()) << '\n';
74
Calling 'toString'
361 }
362
363 OS << ")\n";
364}
365
366bool DWARFDie::isSubprogramDIE() const { return getTag() == DW_TAG_subprogram; }
367
368bool DWARFDie::isSubroutineDIE() const {
369 auto Tag = getTag();
370 return Tag == DW_TAG_subprogram || Tag == DW_TAG_inlined_subroutine;
371}
372
373Optional<DWARFFormValue> DWARFDie::find(dwarf::Attribute Attr) const {
374 if (!isValid())
375 return None;
376 auto AbbrevDecl = getAbbreviationDeclarationPtr();
377 if (AbbrevDecl)
378 return AbbrevDecl->getAttributeValue(getOffset(), Attr, *U);
379 return None;
380}
381
382Optional<DWARFFormValue>
383DWARFDie::find(ArrayRef<dwarf::Attribute> Attrs) const {
384 if (!isValid())
385 return None;
386 auto AbbrevDecl = getAbbreviationDeclarationPtr();
387 if (AbbrevDecl) {
388 for (auto Attr : Attrs) {
389 if (auto Value = AbbrevDecl->getAttributeValue(getOffset(), Attr, *U))
390 return Value;
391 }
392 }
393 return None;
394}
395
396Optional<DWARFFormValue>
397DWARFDie::findRecursively(ArrayRef<dwarf::Attribute> Attrs) const {
398 std::vector<DWARFDie> Worklist;
399 Worklist.push_back(*this);
400
401 // Keep track if DIEs already seen to prevent infinite recursion.
402 // Empirically we rarely see a depth of more than 3 when dealing with valid
403 // DWARF. This corresponds to following the DW_AT_abstract_origin and
404 // DW_AT_specification just once.
405 SmallSet<DWARFDie, 3> Seen;
406
407 while (!Worklist.empty()) {
408 DWARFDie Die = Worklist.back();
409 Worklist.pop_back();
410
411 if (!Die.isValid())
412 continue;
413
414 if (Seen.count(Die))
415 continue;
416
417 Seen.insert(Die);
418
419 if (auto Value = Die.find(Attrs))
420 return Value;
421
422 if (auto D = Die.getAttributeValueAsReferencedDie(DW_AT_abstract_origin))
423 Worklist.push_back(D);
424
425 if (auto D = Die.getAttributeValueAsReferencedDie(DW_AT_specification))
426 Worklist.push_back(D);
427 }
428
429 return None;
430}
431
432DWARFDie
433DWARFDie::getAttributeValueAsReferencedDie(dwarf::Attribute Attr) const {
434 if (Optional<DWARFFormValue> F = find(Attr))
435 return getAttributeValueAsReferencedDie(*F);
436 return DWARFDie();
437}
438
439DWARFDie
440DWARFDie::getAttributeValueAsReferencedDie(const DWARFFormValue &V) const {
441 if (auto SpecRef = toReference(V)) {
442 if (auto SpecUnit = U->getUnitVector().getUnitForOffset(*SpecRef))
443 return SpecUnit->getDIEForOffset(*SpecRef);
444 }
445 return DWARFDie();
446}
447
448Optional<uint64_t> DWARFDie::getRangesBaseAttribute() const {
449 return toSectionOffset(find({DW_AT_rnglists_base, DW_AT_GNU_ranges_base}));
450}
451
452Optional<uint64_t> DWARFDie::getHighPC(uint64_t LowPC) const {
453 if (auto FormValue = find(DW_AT_high_pc)) {
454 if (auto Address = FormValue->getAsAddress()) {
455 // High PC is an address.
456 return Address;
457 }
458 if (auto Offset = FormValue->getAsUnsignedConstant()) {
459 // High PC is an offset from LowPC.
460 return LowPC + *Offset;
461 }
462 }
463 return None;
464}
465
466bool DWARFDie::getLowAndHighPC(uint64_t &LowPC, uint64_t &HighPC,
467 uint64_t &SectionIndex) const {
468 auto F = find(DW_AT_low_pc);
469 auto LowPcAddr = toSectionedAddress(F);
470 if (!LowPcAddr)
471 return false;
472 if (auto HighPcAddr = getHighPC(LowPcAddr->Address)) {
473 LowPC = LowPcAddr->Address;
474 HighPC = *HighPcAddr;
475 SectionIndex = LowPcAddr->SectionIndex;
476 return true;
477 }
478 return false;
479}
480
481Expected<DWARFAddressRangesVector> DWARFDie::getAddressRanges() const {
482 if (isNULL())
483 return DWARFAddressRangesVector();
484 // Single range specified by low/high PC.
485 uint64_t LowPC, HighPC, Index;
486 if (getLowAndHighPC(LowPC, HighPC, Index))
487 return DWARFAddressRangesVector{{LowPC, HighPC, Index}};
488
489 Optional<DWARFFormValue> Value = find(DW_AT_ranges);
490 if (Value) {
491 if (Value->getForm() == DW_FORM_rnglistx)
492 return U->findRnglistFromIndex(*Value->getAsSectionOffset());
493 return U->findRnglistFromOffset(*Value->getAsSectionOffset());
494 }
495 return DWARFAddressRangesVector();
496}
497
498void DWARFDie::collectChildrenAddressRanges(
499 DWARFAddressRangesVector &Ranges) const {
500 if (isNULL())
501 return;
502 if (isSubprogramDIE()) {
503 if (auto DIERangesOrError = getAddressRanges())
504 Ranges.insert(Ranges.end(), DIERangesOrError.get().begin(),
505 DIERangesOrError.get().end());
506 else
507 llvm::consumeError(DIERangesOrError.takeError());
508 }
509
510 for (auto Child : children())
511 Child.collectChildrenAddressRanges(Ranges);
512}
513
514bool DWARFDie::addressRangeContainsAddress(const uint64_t Address) const {
515 auto RangesOrError = getAddressRanges();
516 if (!RangesOrError) {
517 llvm::consumeError(RangesOrError.takeError());
518 return false;
519 }
520
521 for (const auto &R : RangesOrError.get())
522 if (R.LowPC <= Address && Address < R.HighPC)
523 return true;
524 return false;
525}
526
527const char *DWARFDie::getSubroutineName(DINameKind Kind) const {
528 if (!isSubroutineDIE())
529 return nullptr;
530 return getName(Kind);
531}
532
533const char *DWARFDie::getName(DINameKind Kind) const {
534 if (!isValid() || Kind == DINameKind::None)
535 return nullptr;
536 // Try to get mangled name only if it was asked for.
537 if (Kind == DINameKind::LinkageName) {
538 if (auto Name = dwarf::toString(
539 findRecursively({DW_AT_MIPS_linkage_name, DW_AT_linkage_name}),
540 nullptr))
541 return Name;
542 }
543 if (auto Name = dwarf::toString(findRecursively(DW_AT_name), nullptr))
544 return Name;
545 return nullptr;
546}
547
548uint64_t DWARFDie::getDeclLine() const {
549 return toUnsigned(findRecursively(DW_AT_decl_line), 0);
550}
551
552void DWARFDie::getCallerFrame(uint32_t &CallFile, uint32_t &CallLine,
553 uint32_t &CallColumn,
554 uint32_t &CallDiscriminator) const {
555 CallFile = toUnsigned(find(DW_AT_call_file), 0);
556 CallLine = toUnsigned(find(DW_AT_call_line), 0);
557 CallColumn = toUnsigned(find(DW_AT_call_column), 0);
558 CallDiscriminator = toUnsigned(find(DW_AT_GNU_discriminator), 0);
559}
560
561/// Helper to dump a DIE with all of its parents, but no siblings.
562static unsigned dumpParentChain(DWARFDie Die, raw_ostream &OS, unsigned Indent,
563 DIDumpOptions DumpOpts) {
564 if (!Die)
565 return Indent;
566 Indent = dumpParentChain(Die.getParent(), OS, Indent, DumpOpts);
567 Die.dump(OS, Indent, DumpOpts);
568 return Indent + 2;
569}
570
571void DWARFDie::dump(raw_ostream &OS, unsigned Indent,
572 DIDumpOptions DumpOpts) const {
573 if (!isValid())
2
Assuming the condition is false
3
Taking false branch
22
Assuming the condition is false
23
Taking false branch
574 return;
575 DWARFDataExtractor debug_info_data = U->getDebugInfoExtractor();
576 const uint32_t Offset = getOffset();
577 uint32_t offset = Offset;
578 if (DumpOpts.ShowParents) {
4
Assuming the condition is false
5
Taking false branch
24
Taking false branch
579 DIDumpOptions ParentDumpOpts = DumpOpts;
580 ParentDumpOpts.ShowParents = false;
581 ParentDumpOpts.ShowChildren = false;
582 Indent = dumpParentChain(getParent(), OS, Indent, ParentDumpOpts);
583 }
584
585 if (debug_info_data.isValidOffset(offset)) {
6
Taking true branch
25
Taking true branch
586 uint32_t abbrCode = debug_info_data.getULEB128(&offset);
587 if (DumpOpts.ShowAddresses)
7
Assuming the condition is false
8
Taking false branch
26
Assuming the condition is false
27
Taking false branch
588 WithColor(OS, HighlightColor::Address).get()
589 << format("\n0x%8.8x: ", Offset);
590
591 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
592 auto AbbrevDecl = getAbbreviationDeclarationPtr();
593 if (AbbrevDecl) {
11
Assuming 'AbbrevDecl' is non-null
12
Taking true branch
30
Assuming 'AbbrevDecl' is non-null
31
Taking true branch
594 WithColor(OS, HighlightColor::Tag).get().indent(Indent)
595 << formatv("{0}", getTag());
596 if (DumpOpts.Verbose)
13
Assuming the condition is false
14
Taking false branch
32
Assuming the condition is false
33
Taking false branch
597 OS << format(" [%u] %c", abbrCode,
598 AbbrevDecl->hasChildren() ? '*' : ' ');
599 OS << '\n';
600
601 // Dump all data in the DIE for the attributes.
602 for (const auto &AttrSpec : AbbrevDecl->attributes()) {
15
Assuming '__begin4' is equal to '__end4'
34
Assuming '__begin4' is not equal to '__end4'
603 if (AttrSpec.Form == DW_FORM_implicit_const) {
35
Assuming the condition is false
36
Taking false branch
604 // We are dumping .debug_info section ,
605 // implicit_const attribute values are not really stored here,
606 // but in .debug_abbrev section. So we just skip such attrs.
607 continue;
608 }
609 dumpAttribute(OS, *this, &offset, AttrSpec.Attr, AttrSpec.Form,
37
Calling 'dumpAttribute'
610 Indent, DumpOpts);
611 }
612
613 DWARFDie child = getFirstChild();
614 if (DumpOpts.ShowChildren && DumpOpts.RecurseDepth > 0 && child) {
16
Assuming the condition is true
17
Assuming the condition is true
18
Assuming the condition is true
19
Taking true branch
615 DumpOpts.RecurseDepth--;
616 DIDumpOptions ChildDumpOpts = DumpOpts;
617 ChildDumpOpts.ShowParents = false;
618 while (child) {
20
Loop condition is true. Entering loop body
619 child.dump(OS, Indent + 2, ChildDumpOpts);
21
Calling 'DWARFDie::dump'
620 child = child.getSibling();
621 }
622 }
623 } else {
624 OS << "Abbreviation code not found in 'debug_abbrev' class for code: "
625 << abbrCode << '\n';
626 }
627 } else {
628 OS.indent(Indent) << "NULL\n";
629 }
630 }
631}
632
633LLVM_DUMP_METHOD__attribute__((noinline)) __attribute__((__used__)) void DWARFDie::dump() const { dump(llvm::errs(), 0); }
1
Calling 'DWARFDie::dump'
634
635DWARFDie DWARFDie::getParent() const {
636 if (isValid())
637 return U->getParent(Die);
638 return DWARFDie();
639}
640
641DWARFDie DWARFDie::getSibling() const {
642 if (isValid())
643 return U->getSibling(Die);
644 return DWARFDie();
645}
646
647DWARFDie DWARFDie::getPreviousSibling() const {
648 if (isValid())
649 return U->getPreviousSibling(Die);
650 return DWARFDie();
651}
652
653DWARFDie DWARFDie::getFirstChild() const {
654 if (isValid())
655 return U->getFirstChild(Die);
656 return DWARFDie();
657}
658
659DWARFDie DWARFDie::getLastChild() const {
660 if (isValid())
661 return U->getLastChild(Die);
662 return DWARFDie();
663}
664
665iterator_range<DWARFDie::attribute_iterator> DWARFDie::attributes() const {
666 return make_range(attribute_iterator(*this, false),
667 attribute_iterator(*this, true));
668}
669
670DWARFDie::attribute_iterator::attribute_iterator(DWARFDie D, bool End)
671 : Die(D), AttrValue(0), Index(0) {
672 auto AbbrDecl = Die.getAbbreviationDeclarationPtr();
673 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-8~svn350071/lib/DebugInfo/DWARF/DWARFDie.cpp"
, 673, __PRETTY_FUNCTION__))
;
674 if (End) {
675 // This is the end iterator so we set the index to the attribute count.
676 Index = AbbrDecl->getNumAttributes();
677 } else {
678 // This is the begin iterator so we extract the value for this->Index.
679 AttrValue.Offset = D.getOffset() + AbbrDecl->getCodeByteSize();
680 updateForIndex(*AbbrDecl, 0);
681 }
682}
683
684void DWARFDie::attribute_iterator::updateForIndex(
685 const DWARFAbbreviationDeclaration &AbbrDecl, uint32_t I) {
686 Index = I;
687 // AbbrDecl must be valid before calling this function.
688 auto NumAttrs = AbbrDecl.getNumAttributes();
689 if (Index < NumAttrs) {
690 AttrValue.Attr = AbbrDecl.getAttrByIndex(Index);
691 // Add the previous byte size of any previous attribute value.
692 AttrValue.Offset += AttrValue.ByteSize;
693 AttrValue.Value.setForm(AbbrDecl.getFormByIndex(Index));
694 uint32_t ParseOffset = AttrValue.Offset;
695 auto U = Die.getDwarfUnit();
696 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-8~svn350071/lib/DebugInfo/DWARF/DWARFDie.cpp"
, 696, __PRETTY_FUNCTION__))
;
697 bool b = AttrValue.Value.extractValue(U->getDebugInfoExtractor(),
698 &ParseOffset, U->getFormParams(), U);
699 (void)b;
700 assert(b && "extractValue cannot fail on fully parsed DWARF")((b && "extractValue cannot fail on fully parsed DWARF"
) ? static_cast<void> (0) : __assert_fail ("b && \"extractValue cannot fail on fully parsed DWARF\""
, "/build/llvm-toolchain-snapshot-8~svn350071/lib/DebugInfo/DWARF/DWARFDie.cpp"
, 700, __PRETTY_FUNCTION__))
;
701 AttrValue.ByteSize = ParseOffset - AttrValue.Offset;
702 } else {
703 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-8~svn350071/lib/DebugInfo/DWARF/DWARFDie.cpp"
, 703, __PRETTY_FUNCTION__))
;
704 AttrValue.clear();
705 }
706}
707
708DWARFDie::attribute_iterator &DWARFDie::attribute_iterator::operator++() {
709 if (auto AbbrDecl = Die.getAbbreviationDeclarationPtr())
710 updateForIndex(*AbbrDecl, Index + 1);
711 return *this;
712}

/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h

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
43namespace llvm {
44
45class ErrorSuccess;
46
47/// Base class for error info classes. Do not extend this directly: Extend
48/// the ErrorInfo template subclass instead.
49class ErrorInfoBase {
50public:
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
87private:
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.
158class 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
175protected:
176 /// Create a success value. Prefer using 'Error::success()' for readability
177 Error() {
178 setPtr(nullptr);
179 setChecked(false);
180 }
181
182public:
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);
89
Potential leak of memory pointed to by 'Payload._M_t._M_head_impl'
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
254private:
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.
325class ErrorSuccess final : public Error {};
326
327inline ErrorSuccess Error::success() { return ErrorSuccess(); }
328
329/// Make a Error instance representing failure using the given error info
330/// type.
331template <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.
344template <typename ThisErrT, typename ParentErrT = ErrorInfoBase>
345class ErrorInfo : public ParentErrT {
346public:
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.
360class 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
369public:
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
383private:
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~svn350071/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~svn350071/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)
81
Taking false branch
394 return E2;
395 if (!E2)
82
Taking false branch
396 return E1;
397 if (E1.isA<ErrorList>()) {
83
Assuming the condition is false
84
Taking false branch
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>()) {
85
Assuming the condition is false
86
Taking false branch
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>(
88
Calling constructor for 'Error'
415 new ErrorList(E1.takePayload(), E2.takePayload())));
87
Memory is allocated
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.
424inline 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.
434template <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
444public:
445 using storage_type = typename std::conditional<isRef, wrap, T>::type;
446 using value_type = T;
447
448private:
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
454public:
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~svn350071/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
584private:
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~svn350071/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~svn350071/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~svn350071/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~svn350071/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.
688LLVM_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
704inline 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~svn350071/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
725template <typename T>
726T 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~svn350071/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
749template <typename T>
750T& 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~svn350071/include/llvm/Support/Error.h"
, 756)
;
757 }
758}
759
760/// Helper for testing applicability of, and applying, handlers for
761/// ErrorInfo types.
762template <typename HandlerT>
763class ErrorHandlerTraits
764 : public ErrorHandlerTraits<decltype(
765 &std::remove_reference<HandlerT>::type::operator())> {};
766
767// Specialization functions of the form 'Error (const ErrT&)'.
768template <typename ErrT> class ErrorHandlerTraits<Error (&)(ErrT &)> {
769public:
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~svn350071/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&)'.
782template <typename ErrT> class ErrorHandlerTraits<void (&)(ErrT &)> {
783public:
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~svn350071/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>)'.
797template <typename ErrT>
798class ErrorHandlerTraits<Error (&)(std::unique_ptr<ErrT>)> {
799public:
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~svn350071/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>)'.
813template <typename ErrT>
814class ErrorHandlerTraits<void (&)(std::unique_ptr<ErrT>)> {
815public:
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~svn350071/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&)'.
830template <typename C, typename RetT, typename ErrT>
831class ErrorHandlerTraits<RetT (C::*)(ErrT &)>
832 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
833
834// Specialization for member functions of the form 'RetT (const ErrT&) const'.
835template <typename C, typename RetT, typename ErrT>
836class ErrorHandlerTraits<RetT (C::*)(ErrT &) const>
837 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
838
839// Specialization for member functions of the form 'RetT (const ErrT&)'.
840template <typename C, typename RetT, typename ErrT>
841class ErrorHandlerTraits<RetT (C::*)(const ErrT &)>
842 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
843
844// Specialization for member functions of the form 'RetT (const ErrT&) const'.
845template <typename C, typename RetT, typename ErrT>
846class 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>)'.
851template <typename C, typename RetT, typename ErrT>
852class 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'.
857template <typename C, typename RetT, typename ErrT>
858class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>) const>
859 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
860
861inline Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload) {
862 return Error(std::move(Payload));
863}
864
865template <typename HandlerT, typename... HandlerTs>
866Error 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.
881template <typename... HandlerTs>
882Error handleErrors(Error E, HandlerTs &&... Hs) {
883 if (!E)
77
Taking false branch
884 return Error::success();
885
886 std::unique_ptr<ErrorInfoBase> Payload = E.takePayload();
887
888 if (Payload->isA<ErrorList>()) {
78
Assuming the condition is true
79
Taking true branch
889 ErrorList &List = static_cast<ErrorList &>(*Payload);
890 Error R;
891 for (auto &P : List.Payloads)
892 R = ErrorList::join(
80
Calling '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).
904template <typename... HandlerTs>
905void handleAllErrors(Error E, HandlerTs &&... Handlers) {
906 cantFail(handleErrors(std::move(E), std::forward<HandlerTs>(Handlers)...));
76
Calling 'handleErrors<(lambda at /build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h:969:33)>'
907}
908
909/// Check that E is a non-error, then drop it.
910/// If E is an error, llvm_unreachable will be called.
911inline 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
939template <typename T, typename RecoveryFtor, typename... HandlerTs>
940Expected<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 function is compatible with the helpers from Support/WithColor.h. You
957/// can pass any of them as the OS. Please consider using them instead of
958/// including 'error: ' in the ErrorBanner.
959///
960/// This is useful in the base level of your program to allow clean termination
961/// (allowing clean deallocation of resources, etc.), while reporting error
962/// information to the user.
963void logAllUnhandledErrors(Error E, raw_ostream &OS, Twine ErrorBanner = {});
964
965/// Write all error messages (if any) in E to a string. The newline character
966/// is used to separate error messages.
967inline std::string toString(Error E) {
968 SmallVector<std::string, 2> Errors;
969 handleAllErrors(std::move(E), [&Errors](const ErrorInfoBase &EI) {
75
Calling 'handleAllErrors<(lambda at /build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h:969:33)>'
970 Errors.push_back(EI.message());
971 });
972 return join(Errors.begin(), Errors.end(), "\n");
973}
974
975/// Consume a Error without doing anything. This method should be used
976/// only where an error can be considered a reasonable and expected return
977/// value.
978///
979/// Uses of this method are potentially indicative of design problems: If it's
980/// legitimate to do nothing while processing an "error", the error-producer
981/// might be more clearly refactored to return an Optional<T>.
982inline void consumeError(Error Err) {
983 handleAllErrors(std::move(Err), [](const ErrorInfoBase &) {});
984}
985
986/// Helper for converting an Error to a bool.
987///
988/// This method returns true if Err is in an error state, or false if it is
989/// in a success state. Puts Err in a checked state in both cases (unlike
990/// Error::operator bool(), which only does this for success states).
991inline bool errorToBool(Error Err) {
992 bool IsError = static_cast<bool>(Err);
993 if (IsError)
994 consumeError(std::move(Err));
995 return IsError;
996}
997
998/// Helper for Errors used as out-parameters.
999///
1000/// This helper is for use with the Error-as-out-parameter idiom, where an error
1001/// is passed to a function or method by reference, rather than being returned.
1002/// In such cases it is helpful to set the checked bit on entry to the function
1003/// so that the error can be written to (unchecked Errors abort on assignment)
1004/// and clear the checked bit on exit so that clients cannot accidentally forget
1005/// to check the result. This helper performs these actions automatically using
1006/// RAII:
1007///
1008/// @code{.cpp}
1009/// Result foo(Error &Err) {
1010/// ErrorAsOutParameter ErrAsOutParam(&Err); // 'Checked' flag set
1011/// // <body of foo>
1012/// // <- 'Checked' flag auto-cleared when ErrAsOutParam is destructed.
1013/// }
1014/// @endcode
1015///
1016/// ErrorAsOutParameter takes an Error* rather than Error& so that it can be
1017/// used with optional Errors (Error pointers that are allowed to be null). If
1018/// ErrorAsOutParameter took an Error reference, an instance would have to be
1019/// created inside every condition that verified that Error was non-null. By
1020/// taking an Error pointer we can just create one instance at the top of the
1021/// function.
1022class ErrorAsOutParameter {
1023public:
1024 ErrorAsOutParameter(Error *Err) : Err(Err) {
1025 // Raise the checked bit if Err is success.
1026 if (Err)
1027 (void)!!*Err;
1028 }
1029
1030 ~ErrorAsOutParameter() {
1031 // Clear the checked bit.
1032 if (Err && !*Err)
1033 *Err = Error::success();
1034 }
1035
1036private:
1037 Error *Err;
1038};
1039
1040/// Helper for Expected<T>s used as out-parameters.
1041///
1042/// See ErrorAsOutParameter.
1043template <typename T>
1044class ExpectedAsOutParameter {
1045public:
1046 ExpectedAsOutParameter(Expected<T> *ValOrErr)
1047 : ValOrErr(ValOrErr) {
1048 if (ValOrErr)
1049 (void)!!*ValOrErr;
1050 }
1051
1052 ~ExpectedAsOutParameter() {
1053 if (ValOrErr)
1054 ValOrErr->setUnchecked();
1055 }
1056
1057private:
1058 Expected<T> *ValOrErr;
1059};
1060
1061/// This class wraps a std::error_code in a Error.
1062///
1063/// This is useful if you're writing an interface that returns a Error
1064/// (or Expected) and you want to call code that still returns
1065/// std::error_codes.
1066class ECError : public ErrorInfo<ECError> {
1067 friend Error errorCodeToError(std::error_code);
1068
1069public:
1070 void setErrorCode(std::error_code EC) { this->EC = EC; }
1071 std::error_code convertToErrorCode() const override { return EC; }
1072 void log(raw_ostream &OS) const override { OS << EC.message(); }
1073
1074 // Used by ErrorInfo::classID.
1075 static char ID;
1076
1077protected:
1078 ECError() = default;
1079 ECError(std::error_code EC) : EC(EC) {}
1080
1081 std::error_code EC;
1082};
1083
1084/// The value returned by this function can be returned from convertToErrorCode
1085/// for Error values where no sensible translation to std::error_code exists.
1086/// It should only be used in this situation, and should never be used where a
1087/// sensible conversion to std::error_code is available, as attempts to convert
1088/// to/from this error will result in a fatal error. (i.e. it is a programmatic
1089///error to try to convert such a value).
1090std::error_code inconvertibleErrorCode();
1091
1092/// Helper for converting an std::error_code to a Error.
1093Error errorCodeToError(std::error_code EC);
1094
1095/// Helper for converting an ECError to a std::error_code.
1096///
1097/// This method requires that Err be Error() or an ECError, otherwise it
1098/// will trigger a call to abort().
1099std::error_code errorToErrorCode(Error Err);
1100
1101/// Convert an ErrorOr<T> to an Expected<T>.
1102template <typename T> Expected<T> errorOrToExpected(ErrorOr<T> &&EO) {
1103 if (auto EC = EO.getError())
1104 return errorCodeToError(EC);
1105 return std::move(*EO);
1106}
1107
1108/// Convert an Expected<T> to an ErrorOr<T>.
1109template <typename T> ErrorOr<T> expectedToErrorOr(Expected<T> &&E) {
1110 if (auto Err = E.takeError())
1111 return errorToErrorCode(std::move(Err));
1112 return std::move(*E);
1113}
1114
1115/// This class wraps a string in an Error.
1116///
1117/// StringError is useful in cases where the client is not expected to be able
1118/// to consume the specific error message programmatically (for example, if the
1119/// error message is to be presented to the user).
1120///
1121/// StringError can also be used when additional information is to be printed
1122/// along with a error_code message. Depending on the constructor called, this
1123/// class can either display:
1124/// 1. the error_code message (ECError behavior)
1125/// 2. a string
1126/// 3. the error_code message and a string
1127///
1128/// These behaviors are useful when subtyping is required; for example, when a
1129/// specific library needs an explicit error type. In the example below,
1130/// PDBError is derived from StringError:
1131///
1132/// @code{.cpp}
1133/// Expected<int> foo() {
1134/// return llvm::make_error<PDBError>(pdb_error_code::dia_failed_loading,
1135/// "Additional information");
1136/// }
1137/// @endcode
1138///
1139class StringError : public ErrorInfo<StringError> {
1140public:
1141 static char ID;
1142
1143 // Prints EC + S and converts to EC
1144 StringError(std::error_code EC, const Twine &S = Twine());
1145
1146 // Prints S and converts to EC
1147 StringError(const Twine &S, std::error_code EC);
1148
1149 void log(raw_ostream &OS) const override;
1150 std::error_code convertToErrorCode() const override;
1151
1152 const std::string &getMessage() const { return Msg; }
1153
1154private:
1155 std::string Msg;
1156 std::error_code EC;
1157 const bool PrintMsgOnly = false;
1158};
1159
1160/// Create formatted StringError object.
1161template <typename... Ts>
1162Error createStringError(std::error_code EC, char const *Fmt,
1163 const Ts &... Vals) {
1164 std::string Buffer;
1165 raw_string_ostream Stream(Buffer);
1166 Stream << format(Fmt, Vals...);
1167 return make_error<StringError>(Stream.str(), EC);
1168}
1169
1170Error createStringError(std::error_code EC, char const *Msg);
1171
1172/// This class wraps a filename and another Error.
1173///
1174/// In some cases, an error needs to live along a 'source' name, in order to
1175/// show more detailed information to the user.
1176class FileError final : public ErrorInfo<FileError> {
1177
1178 friend Error createFileError(std::string, Error);
1179
1180public:
1181 void log(raw_ostream &OS) const override {
1182 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~svn350071/include/llvm/Support/Error.h"
, 1182, __PRETTY_FUNCTION__))
;
1183 OS << "'" << FileName << "': ";
1184 Err->log(OS);
1185 }
1186
1187 Error takeError() { return Error(std::move(Err)); }
1188
1189 std::error_code convertToErrorCode() const override;
1190
1191 // Used by ErrorInfo::classID.
1192 static char ID;
1193
1194private:
1195 FileError(std::string F, std::unique_ptr<ErrorInfoBase> E) {
1196 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~svn350071/include/llvm/Support/Error.h"
, 1196, __PRETTY_FUNCTION__))
;
1197 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~svn350071/include/llvm/Support/Error.h"
, 1198, __PRETTY_FUNCTION__))
1198 "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~svn350071/include/llvm/Support/Error.h"
, 1198, __PRETTY_FUNCTION__))
;
1199 FileName = F;
1200 Err = std::move(E);
1201 }
1202
1203 static Error build(std::string F, Error E) {
1204 return Error(std::unique_ptr<FileError>(new FileError(F, E.takePayload())));
1205 }
1206
1207 std::string FileName;
1208 std::unique_ptr<ErrorInfoBase> Err;
1209};
1210
1211/// Concatenate a source file path and/or name with an Error. The resulting
1212/// Error is unchecked.
1213inline Error createFileError(std::string F, Error E) {
1214 return FileError::build(F, std::move(E));
1215}
1216
1217Error createFileError(std::string F, ErrorSuccess) = delete;
1218
1219/// Helper for check-and-exit error handling.
1220///
1221/// For tool use only. NOT FOR USE IN LIBRARY CODE.
1222///
1223class ExitOnError {
1224public:
1225 /// Create an error on exit helper.
1226 ExitOnError(std::string Banner = "", int DefaultErrorExitCode = 1)
1227 : Banner(std::move(Banner)),
1228 GetExitCode([=](const Error &) { return DefaultErrorExitCode; }) {}
1229
1230 /// Set the banner string for any errors caught by operator().
1231 void setBanner(std::string Banner) { this->Banner = std::move(Banner); }
1232
1233 /// Set the exit-code mapper function.
1234 void setExitCodeMapper(std::function<int(const Error &)> GetExitCode) {
1235 this->GetExitCode = std::move(GetExitCode);
1236 }
1237
1238 /// Check Err. If it's in a failure state log the error(s) and exit.
1239 void operator()(Error Err) const { checkError(std::move(Err)); }
1240
1241 /// Check E. If it's in a success state then return the contained value. If
1242 /// it's in a failure state log the error(s) and exit.
1243 template <typename T> T operator()(Expected<T> &&E) const {
1244 checkError(E.takeError());
1245 return std::move(*E);
1246 }
1247
1248 /// Check E. If it's in a success state then return the contained reference. If
1249 /// it's in a failure state log the error(s) and exit.
1250 template <typename T> T& operator()(Expected<T&> &&E) const {
1251 checkError(E.takeError());
1252 return *E;
1253 }
1254
1255private:
1256 void checkError(Error Err) const {
1257 if (Err) {
1258 int ExitCode = GetExitCode(Err);
1259 logAllUnhandledErrors(std::move(Err), errs(), Banner);
1260 exit(ExitCode);
1261 }
1262 }
1263
1264 std::string Banner;
1265 std::function<int(const Error &)> GetExitCode;
1266};
1267
1268/// Conversion from Error to LLVMErrorRef for C error bindings.
1269inline LLVMErrorRef wrap(Error Err) {
1270 return reinterpret_cast<LLVMErrorRef>(Err.takePayload().release());
1271}
1272
1273/// Conversion from LLVMErrorRef to Error for C error bindings.
1274inline Error unwrap(LLVMErrorRef ErrRef) {
1275 return Error(std::unique_ptr<ErrorInfoBase>(
1276 reinterpret_cast<ErrorInfoBase *>(ErrRef)));
1277}
1278
1279} // end namespace llvm
1280
1281#endif // LLVM_SUPPORT_ERROR_H