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 WindowsManifestMerger.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 -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~svn345461/build-llvm/lib/WindowsManifest -I /build/llvm-toolchain-snapshot-8~svn345461/lib/WindowsManifest -I /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/include -I /build/llvm-toolchain-snapshot-8~svn345461/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~svn345461/build-llvm/lib/WindowsManifest -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -fobjc-runtime=gcc -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -o /tmp/scan-build-2018-10-27-211344-32123-1 -x c++ /build/llvm-toolchain-snapshot-8~svn345461/lib/WindowsManifest/WindowsManifestMerger.cpp -faddrsig

/build/llvm-toolchain-snapshot-8~svn345461/lib/WindowsManifest/WindowsManifestMerger.cpp

1//===-- WindowsManifestMerger.cpp ------------------------------*- 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 implements the .manifest merger class.
11//
12//===---------------------------------------------------------------------===//
13
14#include "llvm/WindowsManifest/WindowsManifestMerger.h"
15#include "llvm/Config/config.h"
16#include "llvm/Support/MemoryBuffer.h"
17
18#include <map>
19
20#if LLVM_LIBXML2_ENABLED
21#include <libxml/xmlreader.h>
22#endif
23
24#define TO_XML_CHAR(X)reinterpret_cast<const unsigned char *>(X) reinterpret_cast<const unsigned char *>(X)
25#define FROM_XML_CHAR(X)reinterpret_cast<const char *>(X) reinterpret_cast<const char *>(X)
26
27using namespace llvm;
28using namespace windows_manifest;
29
30char WindowsManifestError::ID = 0;
31
32WindowsManifestError::WindowsManifestError(const Twine &Msg) : Msg(Msg.str()) {}
33
34void WindowsManifestError::log(raw_ostream &OS) const { OS << Msg; }
35
36class WindowsManifestMerger::WindowsManifestMergerImpl {
37public:
38 ~WindowsManifestMergerImpl();
39 Error merge(const MemoryBuffer &Manifest);
40 std::unique_ptr<MemoryBuffer> getMergedManifest();
41
42private:
43 static void errorCallback(void *Ctx, const char *Format, ...);
44 Error getParseError();
45#if LLVM_LIBXML2_ENABLED
46 xmlDocPtr CombinedDoc = nullptr;
47 std::vector<xmlDocPtr> MergedDocs;
48
49 bool Merged = false;
50 struct XmlDeleter {
51 void operator()(xmlChar *Ptr) { xmlFree(Ptr); }
52 void operator()(xmlDoc *Ptr) { xmlFreeDoc(Ptr); }
53 };
54 int BufferSize = 0;
55 std::unique_ptr<xmlChar, XmlDeleter> Buffer;
56#endif
57 bool ParseErrorOccurred = false;
58};
59
60#if LLVM_LIBXML2_ENABLED
61
62static const std::pair<StringRef, StringRef> MtNsHrefsPrefixes[] = {
63 {"urn:schemas-microsoft-com:asm.v1", "ms_asmv1"},
64 {"urn:schemas-microsoft-com:asm.v2", "ms_asmv2"},
65 {"urn:schemas-microsoft-com:asm.v3", "ms_asmv3"},
66 {"http://schemas.microsoft.com/SMI/2005/WindowsSettings",
67 "ms_windowsSettings"},
68 {"urn:schemas-microsoft-com:compatibility.v1", "ms_compatibilityv1"}};
69
70static bool xmlStringsEqual(const unsigned char *A, const unsigned char *B) {
71 // Handle null pointers. Comparison of 2 null pointers returns true because
72 // this indicates the prefix of a default namespace.
73 if (!A || !B)
74 return A == B;
75 return strcmp(FROM_XML_CHAR(A)reinterpret_cast<const char *>(A), FROM_XML_CHAR(B)reinterpret_cast<const char *>(B)) == 0;
76}
77
78static bool isMergeableElement(const unsigned char *ElementName) {
79 for (StringRef S : {"application", "assembly", "assemblyIdentity",
80 "compatibility", "noInherit", "requestedExecutionLevel",
81 "requestedPrivileges", "security", "trustInfo"}) {
82 if (S == FROM_XML_CHAR(ElementName)reinterpret_cast<const char *>(ElementName)) {
83 return true;
84 }
85 }
86 return false;
87}
88
89static xmlNodePtr getChildWithName(xmlNodePtr Parent,
90 const unsigned char *ElementName) {
91 for (xmlNodePtr Child = Parent->children; Child; Child = Child->next) {
92 if (xmlStringsEqual(Child->name, ElementName)) {
93 return Child;
94 }
95 }
96 return nullptr;
97}
98
99static xmlAttrPtr getAttribute(xmlNodePtr Node,
100 const unsigned char *AttributeName) {
101 for (xmlAttrPtr Attribute = Node->properties; Attribute != nullptr;
102 Attribute = Attribute->next) {
103 if (xmlStringsEqual(Attribute->name, AttributeName)) {
104 return Attribute;
105 }
106 }
107 return nullptr;
108}
109
110// Check if namespace specified by HRef1 overrides that of HRef2.
111static bool namespaceOverrides(const unsigned char *HRef1,
112 const unsigned char *HRef2) {
113 auto HRef1Position = llvm::find_if(
114 MtNsHrefsPrefixes, [=](const std::pair<StringRef, StringRef> &Element) {
115 return xmlStringsEqual(HRef1, TO_XML_CHAR(Element.first.data())reinterpret_cast<const unsigned char *>(Element.first.data
())
);
116 });
117 auto HRef2Position = llvm::find_if(
118 MtNsHrefsPrefixes, [=](const std::pair<StringRef, StringRef> &Element) {
119 return xmlStringsEqual(HRef2, TO_XML_CHAR(Element.first.data())reinterpret_cast<const unsigned char *>(Element.first.data
())
);
120 });
121 return HRef1Position < HRef2Position;
122}
123
124// Search for prefix-defined namespace specified by HRef, starting on Node and
125// continuing recursively upwards. Returns the namespace or nullptr if not
126// found.
127static xmlNsPtr search(const unsigned char *HRef, xmlNodePtr Node) {
128 for (xmlNsPtr Def = Node->nsDef; Def; Def = Def->next) {
129 if (Def->prefix && xmlStringsEqual(Def->href, HRef)) {
130 return Def;
131 }
132 }
133 if (Node->parent) {
134 return search(HRef, Node->parent);
135 }
136 return nullptr;
137}
138
139// Return the prefix that corresponds to the HRef. If HRef is not a recognized
140// URI, then just return the HRef itself to use as the prefix.
141static const unsigned char *getPrefixForHref(const unsigned char *HRef) {
142 for (auto &Ns : MtNsHrefsPrefixes) {
143 if (xmlStringsEqual(HRef, TO_XML_CHAR(Ns.first.data())reinterpret_cast<const unsigned char *>(Ns.first.data()
)
)) {
144 return TO_XML_CHAR(Ns.second.data())reinterpret_cast<const unsigned char *>(Ns.second.data(
))
;
145 }
146 }
147 return HRef;
148}
149
150// Search for prefix-defined namespace specified by HRef, starting on Node and
151// continuing recursively upwards. If it is found, then return it. If it is
152// not found, then prefix-define that namespace on the node and return a
153// reference to it.
154static Expected<xmlNsPtr> searchOrDefine(const unsigned char *HRef,
155 xmlNodePtr Node) {
156 if (xmlNsPtr Def = search(HRef, Node))
157 return Def;
158 if (xmlNsPtr Def = xmlNewNs(Node, HRef, getPrefixForHref(HRef)))
159 return Def;
160 return make_error<WindowsManifestError>("failed to create new namespace");
161}
162
163// Set the namespace of OrigionalAttribute on OriginalNode to be that of
164// AdditionalAttribute's.
165static Error copyAttributeNamespace(xmlAttrPtr OriginalAttribute,
166 xmlNodePtr OriginalNode,
167 xmlAttrPtr AdditionalAttribute) {
168
169 Expected<xmlNsPtr> ExplicitOrError =
170 searchOrDefine(AdditionalAttribute->ns->href, OriginalNode);
171 if (!ExplicitOrError)
172 return ExplicitOrError.takeError();
173 OriginalAttribute->ns = std::move(ExplicitOrError.get());
174 return Error::success();
175}
176
177// Return the corresponding namespace definition for the prefix, defined on the
178// given Node. Returns nullptr if there is no such definition.
179static xmlNsPtr getNamespaceWithPrefix(const unsigned char *Prefix,
180 xmlNodePtr Node) {
181 if (Node == nullptr)
182 return nullptr;
183 for (xmlNsPtr Def = Node->nsDef; Def; Def = Def->next) {
184 if (xmlStringsEqual(Def->prefix, Prefix)) {
185 return Def;
186 }
187 }
188 return nullptr;
189}
190
191// Search for the closest inheritable default namespace, starting on (and
192// including) the Node and traveling upwards through parent nodes. Returns
193// nullptr if there are no inheritable default namespaces.
194static xmlNsPtr getClosestDefault(xmlNodePtr Node) {
195 if (xmlNsPtr Ret = getNamespaceWithPrefix(nullptr, Node))
196 return Ret;
197 if (Node->parent == nullptr)
198 return nullptr;
199 return getClosestDefault(Node->parent);
200}
201
202// Merge the attributes of AdditionalNode into OriginalNode. If attributes
203// with identical types are present, they are not duplicated but rather if
204// their values are not consistent and error is thrown. In addition, the
205// higher priority namespace is used for each attribute, EXCEPT in the case
206// of merging two default namespaces and the lower priority namespace
207// definition occurs closer than the higher priority one.
208static Error mergeAttributes(xmlNodePtr OriginalNode,
209 xmlNodePtr AdditionalNode) {
210 xmlNsPtr ClosestDefault = getClosestDefault(OriginalNode);
211 for (xmlAttrPtr Attribute = AdditionalNode->properties; Attribute;
212 Attribute = Attribute->next) {
213 if (xmlAttrPtr OriginalAttribute =
214 getAttribute(OriginalNode, Attribute->name)) {
215 if (!xmlStringsEqual(OriginalAttribute->children->content,
216 Attribute->children->content)) {
217 return make_error<WindowsManifestError>(
218 Twine("conflicting attributes for ") +
219 FROM_XML_CHAR(OriginalNode->name)reinterpret_cast<const char *>(OriginalNode->name));
220 }
221 if (!Attribute->ns) {
222 continue;
223 }
224 if (!OriginalAttribute->ns) {
225 if (auto E = copyAttributeNamespace(OriginalAttribute, OriginalNode,
226 Attribute)) {
227 return E;
228 }
229 continue;
230 }
231 if (namespaceOverrides(OriginalAttribute->ns->href,
232 Attribute->ns->href)) {
233 // In this case, the original attribute has a higher priority namespace
234 // than the incomiing attribute, however the namespace definition of
235 // the lower priority namespace occurs first traveling upwards in the
236 // tree. Therefore the lower priority namespace is applied.
237 if (!OriginalAttribute->ns->prefix && !Attribute->ns->prefix &&
238 ClosestDefault &&
239 xmlStringsEqual(Attribute->ns->href, ClosestDefault->href)) {
240 if (auto E = copyAttributeNamespace(OriginalAttribute, OriginalNode,
241 Attribute)) {
242 return E;
243 }
244 continue;
245 }
246 continue;
247 // This covers the case where the incoming attribute has the higher
248 // priority. The higher priority namespace is applied in all cases
249 // EXCEPT when both of the namespaces are default inherited, and the
250 // closest inherited default is the lower priority one.
251 }
252 if (Attribute->ns->prefix || OriginalAttribute->ns->prefix ||
253 (ClosestDefault && !xmlStringsEqual(OriginalAttribute->ns->href,
254 ClosestDefault->href))) {
255 if (auto E = copyAttributeNamespace(OriginalAttribute, OriginalNode,
256 Attribute)) {
257 return E;
258 }
259 continue;
260 }
261 continue;
262 }
263 // If the incoming attribute is not already found on the node, append it
264 // to the end of the properties list. Also explicitly apply its
265 // namespace as a prefix because it might be contained in a separate
266 // namespace that doesn't use the attribute.
267 xmlAttrPtr NewProp =
268 xmlNewProp(OriginalNode, Attribute->name, Attribute->children->content);
269 Expected<xmlNsPtr> ExplicitOrError =
270 searchOrDefine(Attribute->ns->href, OriginalNode);
271 if (!ExplicitOrError)
272 return ExplicitOrError.takeError();
273 NewProp->ns = std::move(ExplicitOrError.get());
274 }
275 return Error::success();
276}
277
278// Given two nodes, return the one with the higher priority namespace.
279static xmlNodePtr getDominantNode(xmlNodePtr Node1, xmlNodePtr Node2) {
280
281 if (!Node1 || !Node1->ns)
282 return Node2;
283 if (!Node2 || !Node2->ns)
284 return Node1;
285 if (namespaceOverrides(Node1->ns->href, Node2->ns->href))
286 return Node1;
287 return Node2;
288}
289
290// Checks if this Node's namespace is inherited or one it defined itself.
291static bool hasInheritedNs(xmlNodePtr Node) {
292 return Node->ns && Node->ns != getNamespaceWithPrefix(Node->ns->prefix, Node);
293}
294
295// Check if this Node's namespace is a default namespace that it inherited, as
296// opposed to defining itself.
297static bool hasInheritedDefaultNs(xmlNodePtr Node) {
298 return hasInheritedNs(Node) && Node->ns->prefix == nullptr;
299}
300
301// Check if this Node's namespace is a default namespace it defined itself.
302static bool hasDefinedDefaultNamespace(xmlNodePtr Node) {
303 return Node->ns && (Node->ns == getNamespaceWithPrefix(nullptr, Node));
304}
305
306// For the given explicit prefix-definition of a namespace, travel downwards
307// from a node recursively, and for every implicit, inherited default usage of
308// that namespace replace it with that explicit prefix use. This is important
309// when namespace overriding occurs when merging, so that elements unique to a
310// namespace will still stay in that namespace.
311static void explicateNamespace(xmlNsPtr PrefixDef, xmlNodePtr Node) {
312 // If a node as its own default namespace definition it clearly cannot have
313 // inherited the given default namespace, and neither will any of its
314 // children.
315 if (hasDefinedDefaultNamespace(Node))
316 return;
317 if (Node->ns && xmlStringsEqual(Node->ns->href, PrefixDef->href) &&
318 hasInheritedDefaultNs(Node))
319 Node->ns = PrefixDef;
320 for (xmlAttrPtr Attribute = Node->properties; Attribute;
321 Attribute = Attribute->next) {
322 if (Attribute->ns &&
323 xmlStringsEqual(Attribute->ns->href, PrefixDef->href)) {
324 Attribute->ns = PrefixDef;
325 }
326 }
327 for (xmlNodePtr Child = Node->children; Child; Child = Child->next) {
328 explicateNamespace(PrefixDef, Child);
329 }
330}
331
332// Perform the namespace merge between two nodes.
333static Error mergeNamespaces(xmlNodePtr OriginalNode,
334 xmlNodePtr AdditionalNode) {
335 // Save the original default namespace definition in case the incoming node
336 // overrides it.
337 const unsigned char *OriginalDefinedDefaultHref = nullptr;
338 if (xmlNsPtr OriginalDefinedDefaultNs =
339 getNamespaceWithPrefix(nullptr, OriginalNode)) {
340 OriginalDefinedDefaultHref = xmlStrdup(OriginalDefinedDefaultNs->href);
341 }
342 const unsigned char *NewDefinedDefaultHref = nullptr;
343 // Copy all namespace definitions. There can only be one default namespace
344 // definition per node, so the higher priority one takes precedence in the
345 // case of collision.
346 for (xmlNsPtr Def = AdditionalNode->nsDef; Def; Def = Def->next) {
347 if (xmlNsPtr OriginalNsDef =
348 getNamespaceWithPrefix(Def->prefix, OriginalNode)) {
349 if (!Def->prefix) {
350 if (namespaceOverrides(Def->href, OriginalNsDef->href)) {
351 NewDefinedDefaultHref = TO_XML_CHAR(strdup(FROM_XML_CHAR(Def->href)))reinterpret_cast<const unsigned char *>(strdup(reinterpret_cast
<const char *>(Def->href)))
;
352 }
353 } else if (!xmlStringsEqual(OriginalNsDef->href, Def->href)) {
354 return make_error<WindowsManifestError>(
355 Twine("conflicting namespace definitions for ") +
356 FROM_XML_CHAR(Def->prefix)reinterpret_cast<const char *>(Def->prefix));
357 }
358 } else {
359 xmlNsPtr NewDef = xmlCopyNamespace(Def);
360 NewDef->next = OriginalNode->nsDef;
361 OriginalNode->nsDef = NewDef;
362 }
363 }
364
365 // Check whether the original node or the incoming node has the higher
366 // priority namespace. Depending on which one is dominant, we will have
367 // to recursively apply namespace changes down to children of the original
368 // node.
369 xmlNodePtr DominantNode = getDominantNode(OriginalNode, AdditionalNode);
370 xmlNodePtr NonDominantNode =
371 DominantNode == OriginalNode ? AdditionalNode : OriginalNode;
372 if (DominantNode == OriginalNode) {
373 if (OriginalDefinedDefaultHref) {
374 xmlNsPtr NonDominantDefinedDefault =
375 getNamespaceWithPrefix(nullptr, NonDominantNode);
376 // In this case, both the nodes defined a default namespace. However
377 // the lower priority node ended up having a higher priority default
378 // definition. This can occur if the higher priority node is prefix
379 // namespace defined. In this case we have to define an explicit
380 // prefix for the overridden definition and apply it to all children
381 // who relied on that definition.
382 if (NonDominantDefinedDefault &&
383 namespaceOverrides(NonDominantDefinedDefault->href,
384 OriginalDefinedDefaultHref)) {
385 Expected<xmlNsPtr> EC =
386 searchOrDefine(OriginalDefinedDefaultHref, DominantNode);
387 if (!EC) {
388 return EC.takeError();
389 }
390 xmlNsPtr PrefixDominantDefinedDefault = std::move(EC.get());
391 explicateNamespace(PrefixDominantDefinedDefault, DominantNode);
392 }
393 // In this case the node with a higher priority namespace did not have a
394 // default namespace definition, but the lower priority node did. In this
395 // case the new default namespace definition is copied. A side effect of
396 // this is that all children will suddenly find themselves in a different
397 // default namespace. To maintain correctness we need to ensure that all
398 // children now explicitly refer to the namespace that they had previously
399 // implicitly inherited.
400 } else if (getNamespaceWithPrefix(nullptr, NonDominantNode)) {
401 if (DominantNode->parent) {
402 xmlNsPtr ClosestDefault = getClosestDefault(DominantNode->parent);
403 Expected<xmlNsPtr> EC =
404 searchOrDefine(ClosestDefault->href, DominantNode);
405 if (!EC) {
406 return EC.takeError();
407 }
408 xmlNsPtr ExplicitDefault = std::move(EC.get());
409 explicateNamespace(ExplicitDefault, DominantNode);
410 }
411 }
412 } else {
413 // Covers case where the incoming node has a default namespace definition
414 // that overrides the original node's namespace. This always leads to
415 // the original node receiving that new default namespace.
416 if (hasDefinedDefaultNamespace(DominantNode)) {
417 NonDominantNode->ns = getNamespaceWithPrefix(nullptr, NonDominantNode);
418 } else {
419 // This covers the case where the incoming node either has a prefix
420 // namespace, or an inherited default namespace. Since the namespace
421 // may not yet be defined in the original tree we do a searchOrDefine
422 // for it, and then set the namespace equal to it.
423 Expected<xmlNsPtr> EC =
424 searchOrDefine(DominantNode->ns->href, NonDominantNode);
425 if (!EC) {
426 return EC.takeError();
427 }
428 xmlNsPtr Explicit = std::move(EC.get());
429 NonDominantNode->ns = Explicit;
430 }
431 // This covers cases where the incoming dominant node HAS a default
432 // namespace definition, but MIGHT NOT NECESSARILY be in that namespace.
433 if (xmlNsPtr DominantDefaultDefined =
434 getNamespaceWithPrefix(nullptr, DominantNode)) {
435 if (OriginalDefinedDefaultHref) {
436 if (namespaceOverrides(DominantDefaultDefined->href,
437 OriginalDefinedDefaultHref)) {
438 // In this case, the incoming node's default definition overrides
439 // the original default definition, all children who relied on that
440 // definition must be updated accordingly.
441 Expected<xmlNsPtr> EC =
442 searchOrDefine(OriginalDefinedDefaultHref, NonDominantNode);
443 if (!EC) {
444 return EC.takeError();
445 }
446 xmlNsPtr ExplicitDefault = std::move(EC.get());
447 explicateNamespace(ExplicitDefault, NonDominantNode);
448 }
449 } else {
450 // The original did not define a default definition, however the new
451 // default definition still applies to all children, so they must be
452 // updated to explicitly refer to the namespace they had previously
453 // been inheriting implicitly.
454 xmlNsPtr ClosestDefault = getClosestDefault(NonDominantNode);
455 Expected<xmlNsPtr> EC =
456 searchOrDefine(ClosestDefault->href, NonDominantNode);
457 if (!EC) {
458 return EC.takeError();
459 }
460 xmlNsPtr ExplicitDefault = std::move(EC.get());
461 explicateNamespace(ExplicitDefault, NonDominantNode);
462 }
463 }
464 }
465 if (NewDefinedDefaultHref) {
466 xmlNsPtr OriginalNsDef = getNamespaceWithPrefix(nullptr, OriginalNode);
467 xmlFree(const_cast<unsigned char *>(OriginalNsDef->href));
468 OriginalNsDef->href = NewDefinedDefaultHref;
469 }
470 xmlFree(const_cast<unsigned char *>(OriginalDefinedDefaultHref));
471 return Error::success();
472}
473
474static bool isRecognizedNamespace(const unsigned char *NsHref) {
475 for (auto &Ns : MtNsHrefsPrefixes) {
476 if (xmlStringsEqual(NsHref, TO_XML_CHAR(Ns.first.data())reinterpret_cast<const unsigned char *>(Ns.first.data()
)
)) {
477 return true;
478 }
479 }
480 return false;
481}
482
483static bool hasRecognizedNamespace(xmlNodePtr Node) {
484 return isRecognizedNamespace(Node->ns->href);
485}
486
487// Ensure a node's inherited namespace is actually defined in the tree it
488// resides in.
489static Error reconcileNamespaces(xmlNodePtr Node) {
490 if (!Node) {
491 return Error::success();
492 }
493 if (hasInheritedNs(Node)) {
494 Expected<xmlNsPtr> ExplicitOrError = searchOrDefine(Node->ns->href, Node);
495 if (!ExplicitOrError) {
496 return ExplicitOrError.takeError();
497 }
498 xmlNsPtr Explicit = std::move(ExplicitOrError.get());
499 Node->ns = Explicit;
500 }
501 for (xmlNodePtr Child = Node->children; Child; Child = Child->next) {
502 if (auto E = reconcileNamespaces(Child)) {
503 return E;
504 }
505 }
506 return Error::success();
507}
508
509// Recursively merge the two given manifest trees, depending on which elements
510// are of a mergeable type, and choose namespaces according to which have
511// higher priority.
512static Error treeMerge(xmlNodePtr OriginalRoot, xmlNodePtr AdditionalRoot) {
513 if (auto E = mergeAttributes(OriginalRoot, AdditionalRoot))
514 return E;
515 if (auto E = mergeNamespaces(OriginalRoot, AdditionalRoot))
516 return E;
517 xmlNodePtr AdditionalFirstChild = AdditionalRoot->children;
518 xmlNode StoreNext;
519 for (xmlNodePtr Child = AdditionalFirstChild; Child; Child = Child->next) {
520 xmlNodePtr OriginalChildWithName;
521 if (!isMergeableElement(Child->name) ||
522 !(OriginalChildWithName =
523 getChildWithName(OriginalRoot, Child->name)) ||
524 !hasRecognizedNamespace(Child)) {
525 StoreNext.next = Child->next;
526 xmlUnlinkNode(Child);
527 if (!xmlAddChild(OriginalRoot, Child)) {
528 return make_error<WindowsManifestError>(Twine("could not merge ") +
529 FROM_XML_CHAR(Child->name)reinterpret_cast<const char *>(Child->name));
530 }
531 if (auto E = reconcileNamespaces(Child)) {
532 return E;
533 }
534 Child = &StoreNext;
535 } else if (auto E = treeMerge(OriginalChildWithName, Child)) {
536 return E;
537 }
538 }
539 return Error::success();
540}
541
542static void stripComments(xmlNodePtr Root) {
543 xmlNode StoreNext;
544 for (xmlNodePtr Child = Root->children; Child; Child = Child->next) {
545 if (!xmlStringsEqual(Child->name, TO_XML_CHAR("comment")reinterpret_cast<const unsigned char *>("comment"))) {
546 stripComments(Child);
547 continue;
548 }
549 StoreNext.next = Child->next;
550 xmlNodePtr Remove = Child;
551 Child = &StoreNext;
552 xmlUnlinkNode(Remove);
553 xmlFreeNode(Remove);
554 }
555}
556
557// libxml2 assumes that attributes do not inherit default namespaces, whereas
558// the original mt.exe does make this assumption. This function reconciles
559// this by setting all attributes to have the inherited default namespace.
560static void setAttributeNamespaces(xmlNodePtr Node) {
561 for (xmlAttrPtr Attribute = Node->properties; Attribute;
562 Attribute = Attribute->next) {
563 if (!Attribute->ns) {
564 Attribute->ns = getClosestDefault(Node);
565 }
566 }
567 for (xmlNodePtr Child = Node->children; Child; Child = Child->next) {
568 setAttributeNamespaces(Child);
569 }
570}
571
572// The merging process may create too many prefix defined namespaces. This
573// function removes all unnecessary ones from the tree.
574static void checkAndStripPrefixes(xmlNodePtr Node,
575 std::vector<xmlNsPtr> &RequiredPrefixes) {
576 for (xmlNodePtr Child = Node->children; Child; Child = Child->next) {
577 checkAndStripPrefixes(Child, RequiredPrefixes);
578 }
579 if (Node->ns && Node->ns->prefix != nullptr) {
580 xmlNsPtr ClosestDefault = getClosestDefault(Node);
581 if (ClosestDefault &&
582 xmlStringsEqual(ClosestDefault->href, Node->ns->href)) {
583 Node->ns = ClosestDefault;
584 } else if (!llvm::is_contained(RequiredPrefixes, Node->ns)) {
585 RequiredPrefixes.push_back(Node->ns);
586 }
587 }
588 for (xmlAttrPtr Attribute = Node->properties; Attribute;
589 Attribute = Attribute->next) {
590 if (Attribute->ns && Attribute->ns->prefix != nullptr) {
591 xmlNsPtr ClosestDefault = getClosestDefault(Node);
592 if (ClosestDefault &&
593 xmlStringsEqual(ClosestDefault->href, Attribute->ns->href)) {
594 Attribute->ns = ClosestDefault;
595 } else if (!llvm::is_contained(RequiredPrefixes, Node->ns)) {
596 RequiredPrefixes.push_back(Attribute->ns);
597 }
598 }
599 }
600 xmlNsPtr Prev;
601 xmlNs Temp;
602 for (xmlNsPtr Def = Node->nsDef; Def; Def = Def->next) {
603 if (!Def->prefix || llvm::is_contained(RequiredPrefixes, Def)) {
604 Prev = Def;
605 continue;
606 }
607 if (Def == Node->nsDef) {
608 Node->nsDef = Def->next;
609 } else {
610 Prev->next = Def->next;
611 }
612 Temp.next = Def->next;
613 xmlFreeNs(Def);
614 Def = &Temp;
615 }
616}
617
618WindowsManifestMerger::WindowsManifestMergerImpl::~WindowsManifestMergerImpl() {
619 for (auto &Doc : MergedDocs)
620 xmlFreeDoc(Doc);
621}
622
623Error WindowsManifestMerger::WindowsManifestMergerImpl::merge(
624 const MemoryBuffer &Manifest) {
625 if (Merged)
626 return make_error<WindowsManifestError>(
627 "merge after getMergedManifest is not supported");
628 if (Manifest.getBufferSize() == 0)
629 return make_error<WindowsManifestError>(
630 "attempted to merge empty manifest");
631 xmlSetGenericErrorFunc((void *)this,
632 WindowsManifestMergerImpl::errorCallback);
633 xmlDocPtr ManifestXML = xmlReadMemory(
634 Manifest.getBufferStart(), Manifest.getBufferSize(), "manifest.xml",
635 nullptr, XML_PARSE_NOBLANKS | XML_PARSE_NODICT);
636 xmlSetGenericErrorFunc(nullptr, nullptr);
637 if (auto E = getParseError())
638 return E;
639 xmlNodePtr AdditionalRoot = xmlDocGetRootElement(ManifestXML);
640 stripComments(AdditionalRoot);
641 setAttributeNamespaces(AdditionalRoot);
642 if (CombinedDoc == nullptr) {
643 CombinedDoc = ManifestXML;
644 } else {
645 xmlNodePtr CombinedRoot = xmlDocGetRootElement(CombinedDoc);
646 if (!xmlStringsEqual(CombinedRoot->name, AdditionalRoot->name) ||
647 !isMergeableElement(AdditionalRoot->name) ||
648 !hasRecognizedNamespace(AdditionalRoot)) {
649 return make_error<WindowsManifestError>("multiple root nodes");
650 }
651 if (auto E = treeMerge(CombinedRoot, AdditionalRoot)) {
652 return E;
653 }
654 }
655 MergedDocs.push_back(ManifestXML);
656 return Error::success();
657}
658
659std::unique_ptr<MemoryBuffer>
660WindowsManifestMerger::WindowsManifestMergerImpl::getMergedManifest() {
661 if (!Merged) {
662 Merged = true;
663
664 if (!CombinedDoc)
665 return nullptr;
666
667 xmlNodePtr CombinedRoot = xmlDocGetRootElement(CombinedDoc);
668 std::vector<xmlNsPtr> RequiredPrefixes;
669 checkAndStripPrefixes(CombinedRoot, RequiredPrefixes);
670 std::unique_ptr<xmlDoc, XmlDeleter> OutputDoc(
671 xmlNewDoc((const unsigned char *)"1.0"));
672 xmlDocSetRootElement(OutputDoc.get(), CombinedRoot);
673 assert(0 == xmlDocGetRootElement(CombinedDoc))((0 == xmlDocGetRootElement(CombinedDoc)) ? static_cast<void
> (0) : __assert_fail ("0 == xmlDocGetRootElement(CombinedDoc)"
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/WindowsManifest/WindowsManifestMerger.cpp"
, 673, __PRETTY_FUNCTION__))
;
674
675 xmlKeepBlanksDefault(0);
676 xmlChar *Buff = nullptr;
677 xmlDocDumpFormatMemoryEnc(OutputDoc.get(), &Buff, &BufferSize, "UTF-8", 1);
678 Buffer.reset(Buff);
679 }
680
681 return BufferSize ? MemoryBuffer::getMemBufferCopy(StringRef(
682 FROM_XML_CHAR(Buffer.get())reinterpret_cast<const char *>(Buffer.get()), (size_t)BufferSize))
683 : nullptr;
684}
685
686bool windows_manifest::isAvailable() { return true; }
687
688#else
689
690WindowsManifestMerger::WindowsManifestMergerImpl::~WindowsManifestMergerImpl() {
691}
692
693Error WindowsManifestMerger::WindowsManifestMergerImpl::merge(
694 const MemoryBuffer &Manifest) {
695 return make_error<WindowsManifestError>("no libxml2");
2
Calling 'make_error<llvm::windows_manifest::WindowsManifestError, char const (&)[11]>'
696}
697
698std::unique_ptr<MemoryBuffer>
699WindowsManifestMerger::WindowsManifestMergerImpl::getMergedManifest() {
700 return nullptr;
701}
702
703bool windows_manifest::isAvailable() { return false; }
704
705#endif
706
707WindowsManifestMerger::WindowsManifestMerger()
708 : Impl(make_unique<WindowsManifestMergerImpl>()) {}
709
710WindowsManifestMerger::~WindowsManifestMerger() {}
711
712Error WindowsManifestMerger::merge(const MemoryBuffer &Manifest) {
713 return Impl->merge(Manifest);
1
Calling 'WindowsManifestMergerImpl::merge'
714}
715
716std::unique_ptr<MemoryBuffer> WindowsManifestMerger::getMergedManifest() {
717 return Impl->getMergedManifest();
718}
719
720void WindowsManifestMerger::WindowsManifestMergerImpl::errorCallback(
721 void *Ctx, const char *Format, ...) {
722 auto *Merger = (WindowsManifestMergerImpl *)Ctx;
723 Merger->ParseErrorOccurred = true;
724}
725
726Error WindowsManifestMerger::WindowsManifestMergerImpl::getParseError() {
727 if (!ParseErrorOccurred)
728 return Error::success();
729 return make_error<WindowsManifestError>("invalid xml document");
730}

/build/llvm-toolchain-snapshot-8~svn345461/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);
7
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)...));
3
Calling 'make_unique<llvm::windows_manifest::WindowsManifestError, char const (&)[11]>'
5
Returned allocated memory
6
Calling constructor for 'Error'
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~svn345461/include/llvm/Support/Error.h"
, 387, __PRETTY_FUNCTION__))
387 "ErrorList constructor payloads should be singleton errors")((!Payload1->isA<ErrorList>() && !Payload2->
isA<ErrorList>() && "ErrorList constructor payloads should be singleton errors"
) ? static_cast<void> (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 387, __PRETTY_FUNCTION__))
;
388 Payloads.push_back(std::move(Payload1));
389 Payloads.push_back(std::move(Payload2));
390 }
391
392 static Error join(Error E1, Error E2) {
393 if (!E1)
394 return E2;
395 if (!E2)
396 return E1;
397 if (E1.isA<ErrorList>()) {
398 auto &E1List = static_cast<ErrorList &>(*E1.getPtr());
399 if (E2.isA<ErrorList>()) {
400 auto E2Payload = E2.takePayload();
401 auto &E2List = static_cast<ErrorList &>(*E2Payload);
402 for (auto &Payload : E2List.Payloads)
403 E1List.Payloads.push_back(std::move(Payload));
404 } else
405 E1List.Payloads.push_back(E2.takePayload());
406
407 return E1;
408 }
409 if (E2.isA<ErrorList>()) {
410 auto &E2List = static_cast<ErrorList &>(*E2.getPtr());
411 E2List.Payloads.insert(E2List.Payloads.begin(), E1.takePayload());
412 return E2;
413 }
414 return Error(std::unique_ptr<ErrorList>(
415 new ErrorList(E1.takePayload(), E2.takePayload())));
416 }
417
418 std::vector<std::unique_ptr<ErrorInfoBase>> Payloads;
419};
420
421/// Concatenate errors. The resulting Error is unchecked, and contains the
422/// ErrorInfo(s), if any, contained in E1, followed by the
423/// ErrorInfo(s), if any, contained in E2.
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~svn345461/include/llvm/Support/Error.h"
, 463, __PRETTY_FUNCTION__))
;
464 new (getErrorStorage()) error_type(Err.takePayload());
465 }
466
467 /// Forbid to convert from Error::success() implicitly, this avoids having
468 /// Expected<T> foo() { return Error::success(); } which compiles otherwise
469 /// but triggers the assertion above.
470 Expected(ErrorSuccess) = delete;
471
472 /// Create an Expected<T> success value from the given OtherT value, which
473 /// must be convertible to T.
474 template <typename OtherT>
475 Expected(OtherT &&Val,
476 typename std::enable_if<std::is_convertible<OtherT, T>::value>::type
477 * = nullptr)
478 : HasError(false)
479#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
480 // Expected is unchecked upon construction in Debug builds.
481 , Unchecked(true)
482#endif
483 {
484 new (getStorage()) storage_type(std::forward<OtherT>(Val));
485 }
486
487 /// Move construct an Expected<T> value.
488 Expected(Expected &&Other) { moveConstruct(std::move(Other)); }
489
490 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
491 /// must be convertible to T.
492 template <class OtherT>
493 Expected(Expected<OtherT> &&Other,
494 typename std::enable_if<std::is_convertible<OtherT, T>::value>::type
495 * = nullptr) {
496 moveConstruct(std::move(Other));
497 }
498
499 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
500 /// isn't convertible to T.
501 template <class OtherT>
502 explicit Expected(
503 Expected<OtherT> &&Other,
504 typename std::enable_if<!std::is_convertible<OtherT, T>::value>::type * =
505 nullptr) {
506 moveConstruct(std::move(Other));
507 }
508
509 /// Move-assign from another Expected<T>.
510 Expected &operator=(Expected &&Other) {
511 moveAssign(std::move(Other));
512 return *this;
513 }
514
515 /// Destroy an Expected<T>.
516 ~Expected() {
517 assertIsChecked();
518 if (!HasError)
519 getStorage()->~storage_type();
520 else
521 getErrorStorage()->~error_type();
522 }
523
524 /// Return false if there is an error.
525 explicit operator bool() {
526#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
527 Unchecked = HasError;
528#endif
529 return !HasError;
530 }
531
532 /// Returns a reference to the stored T value.
533 reference get() {
534 assertIsChecked();
535 return *getStorage();
536 }
537
538 /// Returns a const reference to the stored T value.
539 const_reference get() const {
540 assertIsChecked();
541 return const_cast<Expected<T> *>(this)->get();
542 }
543
544 /// Check that this Expected<T> is an error of type ErrT.
545 template <typename ErrT> bool errorIsA() const {
546 return HasError && (*getErrorStorage())->template isA<ErrT>();
547 }
548
549 /// Take ownership of the stored error.
550 /// After calling this the Expected<T> is in an indeterminate state that can
551 /// only be safely destructed. No further calls (beside the destructor) should
552 /// be made on the Expected<T> vaule.
553 Error takeError() {
554#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
555 Unchecked = false;
556#endif
557 return HasError ? Error(std::move(*getErrorStorage())) : Error::success();
558 }
559
560 /// Returns a pointer to the stored T value.
561 pointer operator->() {
562 assertIsChecked();
563 return toPointer(getStorage());
564 }
565
566 /// Returns a const pointer to the stored T value.
567 const_pointer operator->() const {
568 assertIsChecked();
569 return toPointer(getStorage());
570 }
571
572 /// Returns a reference to the stored T value.
573 reference operator*() {
574 assertIsChecked();
575 return *getStorage();
576 }
577
578 /// Returns a const reference to the stored T value.
579 const_reference operator*() const {
580 assertIsChecked();
581 return *getStorage();
582 }
583
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~svn345461/include/llvm/Support/Error.h"
, 627, __PRETTY_FUNCTION__))
;
628 return reinterpret_cast<storage_type *>(TStorage.buffer);
629 }
630
631 const storage_type *getStorage() const {
632 assert(!HasError && "Cannot get value when an error exists!")((!HasError && "Cannot get value when an error exists!"
) ? static_cast<void> (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 632, __PRETTY_FUNCTION__))
;
633 return reinterpret_cast<const storage_type *>(TStorage.buffer);
634 }
635
636 error_type *getErrorStorage() {
637 assert(HasError && "Cannot get error when a value exists!")((HasError && "Cannot get error when a value exists!"
) ? static_cast<void> (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 637, __PRETTY_FUNCTION__))
;
638 return reinterpret_cast<error_type *>(ErrorStorage.buffer);
639 }
640
641 const error_type *getErrorStorage() const {
642 assert(HasError && "Cannot get error when a value exists!")((HasError && "Cannot get error when a value exists!"
) ? static_cast<void> (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 642, __PRETTY_FUNCTION__))
;
643 return reinterpret_cast<const error_type *>(ErrorStorage.buffer);
644 }
645
646 // Used by ExpectedAsOutParameter to reset the checked flag.
647 void setUnchecked() {
648#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
649 Unchecked = true;
650#endif
651 }
652
653#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
654 LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn))
655 LLVM_ATTRIBUTE_NOINLINE__attribute__((noinline))
656 void fatalUncheckedExpected() const {
657 dbgs() << "Expected<T> must be checked before access or destruction.\n";
658 if (HasError) {
659 dbgs() << "Unchecked Expected<T> contained error:\n";
660 (*getErrorStorage())->log(dbgs());
661 } else
662 dbgs() << "Expected<T> value was in success state. (Note: Expected<T> "
663 "values in success mode must still be checked prior to being "
664 "destroyed).\n";
665 abort();
666 }
667#endif
668
669 void assertIsChecked() {
670#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
671 if (LLVM_UNLIKELY(Unchecked)__builtin_expect((bool)(Unchecked), false))
672 fatalUncheckedExpected();
673#endif
674 }
675
676 union {
677 AlignedCharArrayUnion<storage_type> TStorage;
678 AlignedCharArrayUnion<error_type> ErrorStorage;
679 };
680 bool HasError : 1;
681#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
682 bool Unchecked : 1;
683#endif
684};
685
686/// Report a serious error, calling any installed error handler. See
687/// ErrorHandling.h.
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~svn345461/include/llvm/Support/Error.h"
, 708)
;
709 }
710}
711
712/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
713/// returns the contained value.
714///
715/// This function can be used to wrap calls to fallible functions ONLY when it
716/// is known that the Error will always be a success value. E.g.
717///
718/// @code{.cpp}
719/// // foo only attempts the fallible operation if DoFallibleOperation is
720/// // true. If DoFallibleOperation is false then foo always returns an int.
721/// Expected<int> foo(bool DoFallibleOperation);
722///
723/// int X = cantFail(foo(false));
724/// @endcode
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~svn345461/include/llvm/Support/Error.h"
, 732)
;
733 }
734}
735
736/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
737/// returns the contained reference.
738///
739/// This function can be used to wrap calls to fallible functions ONLY when it
740/// is known that the Error will always be a success value. E.g.
741///
742/// @code{.cpp}
743/// // foo only attempts the fallible operation if DoFallibleOperation is
744/// // true. If DoFallibleOperation is false then foo always returns a Bar&.
745/// Expected<Bar&> foo(bool DoFallibleOperation);
746///
747/// Bar &X = cantFail(foo(false));
748/// @endcode
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~svn345461/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~svn345461/include/llvm/Support/Error.h"
, 776, __PRETTY_FUNCTION__))
;
777 return H(static_cast<ErrT &>(*E));
778 }
779};
780
781// Specialization functions of the form 'void (const ErrT&)'.
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~svn345461/include/llvm/Support/Error.h"
, 790, __PRETTY_FUNCTION__))
;
791 H(static_cast<ErrT &>(*E));
792 return Error::success();
793 }
794};
795
796/// Specialization for functions of the form 'Error (std::unique_ptr<ErrT>)'.
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~svn345461/include/llvm/Support/Error.h"
, 806, __PRETTY_FUNCTION__))
;
807 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
808 return H(std::move(SubE));
809 }
810};
811
812/// Specialization for functions of the form 'void (std::unique_ptr<ErrT>)'.
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~svn345461/include/llvm/Support/Error.h"
, 822, __PRETTY_FUNCTION__))
;
823 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
824 H(std::move(SubE));
825 return Error::success();
826 }
827};
828
829// Specialization for member functions of the form 'RetT (const ErrT&)'.
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)
884 return Error::success();
885
886 std::unique_ptr<ErrorInfoBase> Payload = E.takePayload();
887
888 if (Payload->isA<ErrorList>()) {
889 ErrorList &List = static_cast<ErrorList &>(*Payload);
890 Error R;
891 for (auto &P : List.Payloads)
892 R = ErrorList::join(
893 std::move(R),
894 handleErrorImpl(std::move(P), std::forward<HandlerTs>(Hs)...));
895 return R;
896 }
897
898 return handleErrorImpl(std::move(Payload), std::forward<HandlerTs>(Hs)...);
899}
900
901/// Behaves the same as handleErrors, except that by contract all errors
902/// *must* be handled by the given handlers (i.e. there must be no remaining
903/// errors after running the handlers, or llvm_unreachable is called).
904template <typename... HandlerTs>
905void handleAllErrors(Error E, HandlerTs &&... Handlers) {
906 cantFail(handleErrors(std::move(E), std::forward<HandlerTs>(Handlers)...));
907}
908
909/// Check that E is a non-error, then drop it.
910/// If E is an error, llvm_unreachable will be called.
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 is useful in the base level of your program to allow clean termination
957/// (allowing clean deallocation of resources, etc.), while reporting error
958/// information to the user.
959void logAllUnhandledErrors(Error E, raw_ostream &OS, Twine ErrorBanner);
960
961/// Write all error messages (if any) in E to a string. The newline character
962/// is used to separate error messages.
963inline std::string toString(Error E) {
964 SmallVector<std::string, 2> Errors;
965 handleAllErrors(std::move(E), [&Errors](const ErrorInfoBase &EI) {
966 Errors.push_back(EI.message());
967 });
968 return join(Errors.begin(), Errors.end(), "\n");
969}
970
971/// Consume a Error without doing anything. This method should be used
972/// only where an error can be considered a reasonable and expected return
973/// value.
974///
975/// Uses of this method are potentially indicative of design problems: If it's
976/// legitimate to do nothing while processing an "error", the error-producer
977/// might be more clearly refactored to return an Optional<T>.
978inline void consumeError(Error Err) {
979 handleAllErrors(std::move(Err), [](const ErrorInfoBase &) {});
980}
981
982/// Helper for converting an Error to a bool.
983///
984/// This method returns true if Err is in an error state, or false if it is
985/// in a success state. Puts Err in a checked state in both cases (unlike
986/// Error::operator bool(), which only does this for success states).
987inline bool errorToBool(Error Err) {
988 bool IsError = static_cast<bool>(Err);
989 if (IsError)
990 consumeError(std::move(Err));
991 return IsError;
992}
993
994/// Helper for Errors used as out-parameters.
995///
996/// This helper is for use with the Error-as-out-parameter idiom, where an error
997/// is passed to a function or method by reference, rather than being returned.
998/// In such cases it is helpful to set the checked bit on entry to the function
999/// so that the error can be written to (unchecked Errors abort on assignment)
1000/// and clear the checked bit on exit so that clients cannot accidentally forget
1001/// to check the result. This helper performs these actions automatically using
1002/// RAII:
1003///
1004/// @code{.cpp}
1005/// Result foo(Error &Err) {
1006/// ErrorAsOutParameter ErrAsOutParam(&Err); // 'Checked' flag set
1007/// // <body of foo>
1008/// // <- 'Checked' flag auto-cleared when ErrAsOutParam is destructed.
1009/// }
1010/// @endcode
1011///
1012/// ErrorAsOutParameter takes an Error* rather than Error& so that it can be
1013/// used with optional Errors (Error pointers that are allowed to be null). If
1014/// ErrorAsOutParameter took an Error reference, an instance would have to be
1015/// created inside every condition that verified that Error was non-null. By
1016/// taking an Error pointer we can just create one instance at the top of the
1017/// function.
1018class ErrorAsOutParameter {
1019public:
1020 ErrorAsOutParameter(Error *Err) : Err(Err) {
1021 // Raise the checked bit if Err is success.
1022 if (Err)
1023 (void)!!*Err;
1024 }
1025
1026 ~ErrorAsOutParameter() {
1027 // Clear the checked bit.
1028 if (Err && !*Err)
1029 *Err = Error::success();
1030 }
1031
1032private:
1033 Error *Err;
1034};
1035
1036/// Helper for Expected<T>s used as out-parameters.
1037///
1038/// See ErrorAsOutParameter.
1039template <typename T>
1040class ExpectedAsOutParameter {
1041public:
1042 ExpectedAsOutParameter(Expected<T> *ValOrErr)
1043 : ValOrErr(ValOrErr) {
1044 if (ValOrErr)
1045 (void)!!*ValOrErr;
1046 }
1047
1048 ~ExpectedAsOutParameter() {
1049 if (ValOrErr)
1050 ValOrErr->setUnchecked();
1051 }
1052
1053private:
1054 Expected<T> *ValOrErr;
1055};
1056
1057/// This class wraps a std::error_code in a Error.
1058///
1059/// This is useful if you're writing an interface that returns a Error
1060/// (or Expected) and you want to call code that still returns
1061/// std::error_codes.
1062class ECError : public ErrorInfo<ECError> {
1063 friend Error errorCodeToError(std::error_code);
1064
1065public:
1066 void setErrorCode(std::error_code EC) { this->EC = EC; }
1067 std::error_code convertToErrorCode() const override { return EC; }
1068 void log(raw_ostream &OS) const override { OS << EC.message(); }
1069
1070 // Used by ErrorInfo::classID.
1071 static char ID;
1072
1073protected:
1074 ECError() = default;
1075 ECError(std::error_code EC) : EC(EC) {}
1076
1077 std::error_code EC;
1078};
1079
1080/// The value returned by this function can be returned from convertToErrorCode
1081/// for Error values where no sensible translation to std::error_code exists.
1082/// It should only be used in this situation, and should never be used where a
1083/// sensible conversion to std::error_code is available, as attempts to convert
1084/// to/from this error will result in a fatal error. (i.e. it is a programmatic
1085///error to try to convert such a value).
1086std::error_code inconvertibleErrorCode();
1087
1088/// Helper for converting an std::error_code to a Error.
1089Error errorCodeToError(std::error_code EC);
1090
1091/// Helper for converting an ECError to a std::error_code.
1092///
1093/// This method requires that Err be Error() or an ECError, otherwise it
1094/// will trigger a call to abort().
1095std::error_code errorToErrorCode(Error Err);
1096
1097/// Convert an ErrorOr<T> to an Expected<T>.
1098template <typename T> Expected<T> errorOrToExpected(ErrorOr<T> &&EO) {
1099 if (auto EC = EO.getError())
1100 return errorCodeToError(EC);
1101 return std::move(*EO);
1102}
1103
1104/// Convert an Expected<T> to an ErrorOr<T>.
1105template <typename T> ErrorOr<T> expectedToErrorOr(Expected<T> &&E) {
1106 if (auto Err = E.takeError())
1107 return errorToErrorCode(std::move(Err));
1108 return std::move(*E);
1109}
1110
1111/// This class wraps a string in an Error.
1112///
1113/// StringError is useful in cases where the client is not expected to be able
1114/// to consume the specific error message programmatically (for example, if the
1115/// error message is to be presented to the user).
1116///
1117/// StringError can also be used when additional information is to be printed
1118/// along with a error_code message. Depending on the constructor called, this
1119/// class can either display:
1120/// 1. the error_code message (ECError behavior)
1121/// 2. a string
1122/// 3. the error_code message and a string
1123///
1124/// These behaviors are useful when subtyping is required; for example, when a
1125/// specific library needs an explicit error type. In the example below,
1126/// PDBError is derived from StringError:
1127///
1128/// @code{.cpp}
1129/// Expected<int> foo() {
1130/// return llvm::make_error<PDBError>(pdb_error_code::dia_failed_loading,
1131/// "Additional information");
1132/// }
1133/// @endcode
1134///
1135class StringError : public ErrorInfo<StringError> {
1136public:
1137 static char ID;
1138
1139 // Prints EC + S and converts to EC
1140 StringError(std::error_code EC, const Twine &S = Twine());
1141
1142 // Prints S and converts to EC
1143 StringError(const Twine &S, std::error_code EC);
1144
1145 void log(raw_ostream &OS) const override;
1146 std::error_code convertToErrorCode() const override;
1147
1148 const std::string &getMessage() const { return Msg; }
1149
1150private:
1151 std::string Msg;
1152 std::error_code EC;
1153 const bool PrintMsgOnly = false;
1154};
1155
1156/// Create formatted StringError object.
1157template <typename... Ts>
1158Error createStringError(std::error_code EC, char const *Fmt,
1159 const Ts &... Vals) {
1160 std::string Buffer;
1161 raw_string_ostream Stream(Buffer);
1162 Stream << format(Fmt, Vals...);
1163 return make_error<StringError>(Stream.str(), EC);
1164}
1165
1166Error createStringError(std::error_code EC, char const *Msg);
1167
1168/// This class wraps a filename and another Error.
1169///
1170/// In some cases, an error needs to live along a 'source' name, in order to
1171/// show more detailed information to the user.
1172class FileError final : public ErrorInfo<FileError> {
1173
1174 friend Error createFileError(std::string, Error);
1175
1176public:
1177 void log(raw_ostream &OS) const override {
1178 assert(Err && !FileName.empty() && "Trying to log after takeError().")((Err && !FileName.empty() && "Trying to log after takeError()."
) ? static_cast<void> (0) : __assert_fail ("Err && !FileName.empty() && \"Trying to log after takeError().\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 1178, __PRETTY_FUNCTION__))
;
1179 OS << "'" << FileName << "': ";
1180 Err->log(OS);
1181 }
1182
1183 Error takeError() { return Error(std::move(Err)); }
1184
1185 std::error_code convertToErrorCode() const override;
1186
1187 // Used by ErrorInfo::classID.
1188 static char ID;
1189
1190private:
1191 FileError(std::string F, std::unique_ptr<ErrorInfoBase> E) {
1192 assert(E && "Cannot create FileError from Error success value.")((E && "Cannot create FileError from Error success value."
) ? static_cast<void> (0) : __assert_fail ("E && \"Cannot create FileError from Error success value.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 1192, __PRETTY_FUNCTION__))
;
1193 assert(!F.empty() &&((!F.empty() && "The file name provided to FileError must not be empty."
) ? static_cast<void> (0) : __assert_fail ("!F.empty() && \"The file name provided to FileError must not be empty.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 1194, __PRETTY_FUNCTION__))
1194 "The file name provided to FileError must not be empty.")((!F.empty() && "The file name provided to FileError must not be empty."
) ? static_cast<void> (0) : __assert_fail ("!F.empty() && \"The file name provided to FileError must not be empty.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 1194, __PRETTY_FUNCTION__))
;
1195 FileName = F;
1196 Err = std::move(E);
1197 }
1198
1199 static Error build(std::string F, Error E) {
1200 return Error(std::unique_ptr<FileError>(new FileError(F, E.takePayload())));
1201 }
1202
1203 std::string FileName;
1204 std::unique_ptr<ErrorInfoBase> Err;
1205};
1206
1207/// Concatenate a source file path and/or name with an Error. The resulting
1208/// Error is unchecked.
1209inline Error createFileError(std::string F, Error E) {
1210 return FileError::build(F, std::move(E));
1211}
1212
1213Error createFileError(std::string F, ErrorSuccess) = delete;
1214
1215/// Helper for check-and-exit error handling.
1216///
1217/// For tool use only. NOT FOR USE IN LIBRARY CODE.
1218///
1219class ExitOnError {
1220public:
1221 /// Create an error on exit helper.
1222 ExitOnError(std::string Banner = "", int DefaultErrorExitCode = 1)
1223 : Banner(std::move(Banner)),
1224 GetExitCode([=](const Error &) { return DefaultErrorExitCode; }) {}
1225
1226 /// Set the banner string for any errors caught by operator().
1227 void setBanner(std::string Banner) { this->Banner = std::move(Banner); }
1228
1229 /// Set the exit-code mapper function.
1230 void setExitCodeMapper(std::function<int(const Error &)> GetExitCode) {
1231 this->GetExitCode = std::move(GetExitCode);
1232 }
1233
1234 /// Check Err. If it's in a failure state log the error(s) and exit.
1235 void operator()(Error Err) const { checkError(std::move(Err)); }
1236
1237 /// Check E. If it's in a success state then return the contained value. If
1238 /// it's in a failure state log the error(s) and exit.
1239 template <typename T> T operator()(Expected<T> &&E) const {
1240 checkError(E.takeError());
1241 return std::move(*E);
1242 }
1243
1244 /// Check E. If it's in a success state then return the contained reference. If
1245 /// it's in a failure state log the error(s) and exit.
1246 template <typename T> T& operator()(Expected<T&> &&E) const {
1247 checkError(E.takeError());
1248 return *E;
1249 }
1250
1251private:
1252 void checkError(Error Err) const {
1253 if (Err) {
1254 int ExitCode = GetExitCode(Err);
1255 logAllUnhandledErrors(std::move(Err), errs(), Banner);
1256 exit(ExitCode);
1257 }
1258 }
1259
1260 std::string Banner;
1261 std::function<int(const Error &)> GetExitCode;
1262};
1263
1264/// Conversion from Error to LLVMErrorRef for C error bindings.
1265inline LLVMErrorRef wrap(Error Err) {
1266 return reinterpret_cast<LLVMErrorRef>(Err.takePayload().release());
1267}
1268
1269/// Conversion from LLVMErrorRef to Error for C error bindings.
1270inline Error unwrap(LLVMErrorRef ErrRef) {
1271 return Error(std::unique_ptr<ErrorInfoBase>(
1272 reinterpret_cast<ErrorInfoBase *>(ErrRef)));
1273}
1274
1275} // end namespace llvm
1276
1277#endif // LLVM_SUPPORT_ERROR_H

/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/ADT/STLExtras.h

1//===- llvm/ADT/STLExtras.h - Useful STL related functions ------*- 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 contains some templates that are useful if you are working with the
11// STL at all.
12//
13// No library is required when using these functions.
14//
15//===----------------------------------------------------------------------===//
16
17#ifndef LLVM_ADT_STLEXTRAS_H
18#define LLVM_ADT_STLEXTRAS_H
19
20#include "llvm/ADT/Optional.h"
21#include "llvm/ADT/SmallVector.h"
22#include "llvm/ADT/iterator.h"
23#include "llvm/ADT/iterator_range.h"
24#include "llvm/Config/abi-breaking.h"
25#include "llvm/Support/ErrorHandling.h"
26#include <algorithm>
27#include <cassert>
28#include <cstddef>
29#include <cstdint>
30#include <cstdlib>
31#include <functional>
32#include <initializer_list>
33#include <iterator>
34#include <limits>
35#include <memory>
36#include <tuple>
37#include <type_traits>
38#include <utility>
39
40#ifdef EXPENSIVE_CHECKS
41#include <random> // for std::mt19937
42#endif
43
44namespace llvm {
45
46// Only used by compiler if both template types are the same. Useful when
47// using SFINAE to test for the existence of member functions.
48template <typename T, T> struct SameType;
49
50namespace detail {
51
52template <typename RangeT>
53using IterOfRange = decltype(std::begin(std::declval<RangeT &>()));
54
55template <typename RangeT>
56using ValueOfRange = typename std::remove_reference<decltype(
57 *std::begin(std::declval<RangeT &>()))>::type;
58
59} // end namespace detail
60
61//===----------------------------------------------------------------------===//
62// Extra additions to <type_traits>
63//===----------------------------------------------------------------------===//
64
65template <typename T>
66struct negation : std::integral_constant<bool, !bool(T::value)> {};
67
68template <typename...> struct conjunction : std::true_type {};
69template <typename B1> struct conjunction<B1> : B1 {};
70template <typename B1, typename... Bn>
71struct conjunction<B1, Bn...>
72 : std::conditional<bool(B1::value), conjunction<Bn...>, B1>::type {};
73
74//===----------------------------------------------------------------------===//
75// Extra additions to <functional>
76//===----------------------------------------------------------------------===//
77
78template <class Ty> struct identity {
79 using argument_type = Ty;
80
81 Ty &operator()(Ty &self) const {
82 return self;
83 }
84 const Ty &operator()(const Ty &self) const {
85 return self;
86 }
87};
88
89template <class Ty> struct less_ptr {
90 bool operator()(const Ty* left, const Ty* right) const {
91 return *left < *right;
92 }
93};
94
95template <class Ty> struct greater_ptr {
96 bool operator()(const Ty* left, const Ty* right) const {
97 return *right < *left;
98 }
99};
100
101/// An efficient, type-erasing, non-owning reference to a callable. This is
102/// intended for use as the type of a function parameter that is not used
103/// after the function in question returns.
104///
105/// This class does not own the callable, so it is not in general safe to store
106/// a function_ref.
107template<typename Fn> class function_ref;
108
109template<typename Ret, typename ...Params>
110class function_ref<Ret(Params...)> {
111 Ret (*callback)(intptr_t callable, Params ...params) = nullptr;
112 intptr_t callable;
113
114 template<typename Callable>
115 static Ret callback_fn(intptr_t callable, Params ...params) {
116 return (*reinterpret_cast<Callable*>(callable))(
117 std::forward<Params>(params)...);
118 }
119
120public:
121 function_ref() = default;
122 function_ref(std::nullptr_t) {}
123
124 template <typename Callable>
125 function_ref(Callable &&callable,
126 typename std::enable_if<
127 !std::is_same<typename std::remove_reference<Callable>::type,
128 function_ref>::value>::type * = nullptr)
129 : callback(callback_fn<typename std::remove_reference<Callable>::type>),
130 callable(reinterpret_cast<intptr_t>(&callable)) {}
131
132 Ret operator()(Params ...params) const {
133 return callback(callable, std::forward<Params>(params)...);
134 }
135
136 operator bool() const { return callback; }
137};
138
139// deleter - Very very very simple method that is used to invoke operator
140// delete on something. It is used like this:
141//
142// for_each(V.begin(), B.end(), deleter<Interval>);
143template <class T>
144inline void deleter(T *Ptr) {
145 delete Ptr;
146}
147
148//===----------------------------------------------------------------------===//
149// Extra additions to <iterator>
150//===----------------------------------------------------------------------===//
151
152namespace adl_detail {
153
154using std::begin;
155
156template <typename ContainerTy>
157auto adl_begin(ContainerTy &&container)
158 -> decltype(begin(std::forward<ContainerTy>(container))) {
159 return begin(std::forward<ContainerTy>(container));
160}
161
162using std::end;
163
164template <typename ContainerTy>
165auto adl_end(ContainerTy &&container)
166 -> decltype(end(std::forward<ContainerTy>(container))) {
167 return end(std::forward<ContainerTy>(container));
168}
169
170using std::swap;
171
172template <typename T>
173void adl_swap(T &&lhs, T &&rhs) noexcept(noexcept(swap(std::declval<T>(),
174 std::declval<T>()))) {
175 swap(std::forward<T>(lhs), std::forward<T>(rhs));
176}
177
178} // end namespace adl_detail
179
180template <typename ContainerTy>
181auto adl_begin(ContainerTy &&container)
182 -> decltype(adl_detail::adl_begin(std::forward<ContainerTy>(container))) {
183 return adl_detail::adl_begin(std::forward<ContainerTy>(container));
184}
185
186template <typename ContainerTy>
187auto adl_end(ContainerTy &&container)
188 -> decltype(adl_detail::adl_end(std::forward<ContainerTy>(container))) {
189 return adl_detail::adl_end(std::forward<ContainerTy>(container));
190}
191
192template <typename T>
193void adl_swap(T &&lhs, T &&rhs) noexcept(
194 noexcept(adl_detail::adl_swap(std::declval<T>(), std::declval<T>()))) {
195 adl_detail::adl_swap(std::forward<T>(lhs), std::forward<T>(rhs));
196}
197
198// mapped_iterator - This is a simple iterator adapter that causes a function to
199// be applied whenever operator* is invoked on the iterator.
200
201template <typename ItTy, typename FuncTy,
202 typename FuncReturnTy =
203 decltype(std::declval<FuncTy>()(*std::declval<ItTy>()))>
204class mapped_iterator
205 : public iterator_adaptor_base<
206 mapped_iterator<ItTy, FuncTy>, ItTy,
207 typename std::iterator_traits<ItTy>::iterator_category,
208 typename std::remove_reference<FuncReturnTy>::type> {
209public:
210 mapped_iterator(ItTy U, FuncTy F)
211 : mapped_iterator::iterator_adaptor_base(std::move(U)), F(std::move(F)) {}
212
213 ItTy getCurrent() { return this->I; }
214
215 FuncReturnTy operator*() { return F(*this->I); }
216
217private:
218 FuncTy F;
219};
220
221// map_iterator - Provide a convenient way to create mapped_iterators, just like
222// make_pair is useful for creating pairs...
223template <class ItTy, class FuncTy>
224inline mapped_iterator<ItTy, FuncTy> map_iterator(ItTy I, FuncTy F) {
225 return mapped_iterator<ItTy, FuncTy>(std::move(I), std::move(F));
226}
227
228/// Helper to determine if type T has a member called rbegin().
229template <typename Ty> class has_rbegin_impl {
230 using yes = char[1];
231 using no = char[2];
232
233 template <typename Inner>
234 static yes& test(Inner *I, decltype(I->rbegin()) * = nullptr);
235
236 template <typename>
237 static no& test(...);
238
239public:
240 static const bool value = sizeof(test<Ty>(nullptr)) == sizeof(yes);
241};
242
243/// Metafunction to determine if T& or T has a member called rbegin().
244template <typename Ty>
245struct has_rbegin : has_rbegin_impl<typename std::remove_reference<Ty>::type> {
246};
247
248// Returns an iterator_range over the given container which iterates in reverse.
249// Note that the container must have rbegin()/rend() methods for this to work.
250template <typename ContainerTy>
251auto reverse(ContainerTy &&C,
252 typename std::enable_if<has_rbegin<ContainerTy>::value>::type * =
253 nullptr) -> decltype(make_range(C.rbegin(), C.rend())) {
254 return make_range(C.rbegin(), C.rend());
255}
256
257// Returns a std::reverse_iterator wrapped around the given iterator.
258template <typename IteratorTy>
259std::reverse_iterator<IteratorTy> make_reverse_iterator(IteratorTy It) {
260 return std::reverse_iterator<IteratorTy>(It);
261}
262
263// Returns an iterator_range over the given container which iterates in reverse.
264// Note that the container must have begin()/end() methods which return
265// bidirectional iterators for this to work.
266template <typename ContainerTy>
267auto reverse(
268 ContainerTy &&C,
269 typename std::enable_if<!has_rbegin<ContainerTy>::value>::type * = nullptr)
270 -> decltype(make_range(llvm::make_reverse_iterator(std::end(C)),
271 llvm::make_reverse_iterator(std::begin(C)))) {
272 return make_range(llvm::make_reverse_iterator(std::end(C)),
273 llvm::make_reverse_iterator(std::begin(C)));
274}
275
276/// An iterator adaptor that filters the elements of given inner iterators.
277///
278/// The predicate parameter should be a callable object that accepts the wrapped
279/// iterator's reference type and returns a bool. When incrementing or
280/// decrementing the iterator, it will call the predicate on each element and
281/// skip any where it returns false.
282///
283/// \code
284/// int A[] = { 1, 2, 3, 4 };
285/// auto R = make_filter_range(A, [](int N) { return N % 2 == 1; });
286/// // R contains { 1, 3 }.
287/// \endcode
288///
289/// Note: filter_iterator_base implements support for forward iteration.
290/// filter_iterator_impl exists to provide support for bidirectional iteration,
291/// conditional on whether the wrapped iterator supports it.
292template <typename WrappedIteratorT, typename PredicateT, typename IterTag>
293class filter_iterator_base
294 : public iterator_adaptor_base<
295 filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>,
296 WrappedIteratorT,
297 typename std::common_type<
298 IterTag, typename std::iterator_traits<
299 WrappedIteratorT>::iterator_category>::type> {
300 using BaseT = iterator_adaptor_base<
301 filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>,
302 WrappedIteratorT,
303 typename std::common_type<
304 IterTag, typename std::iterator_traits<
305 WrappedIteratorT>::iterator_category>::type>;
306
307protected:
308 WrappedIteratorT End;
309 PredicateT Pred;
310
311 void findNextValid() {
312 while (this->I != End && !Pred(*this->I))
313 BaseT::operator++();
314 }
315
316 // Construct the iterator. The begin iterator needs to know where the end
317 // is, so that it can properly stop when it gets there. The end iterator only
318 // needs the predicate to support bidirectional iteration.
319 filter_iterator_base(WrappedIteratorT Begin, WrappedIteratorT End,
320 PredicateT Pred)
321 : BaseT(Begin), End(End), Pred(Pred) {
322 findNextValid();
323 }
324
325public:
326 using BaseT::operator++;
327
328 filter_iterator_base &operator++() {
329 BaseT::operator++();
330 findNextValid();
331 return *this;
332 }
333};
334
335/// Specialization of filter_iterator_base for forward iteration only.
336template <typename WrappedIteratorT, typename PredicateT,
337 typename IterTag = std::forward_iterator_tag>
338class filter_iterator_impl
339 : public filter_iterator_base<WrappedIteratorT, PredicateT, IterTag> {
340 using BaseT = filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>;
341
342public:
343 filter_iterator_impl(WrappedIteratorT Begin, WrappedIteratorT End,
344 PredicateT Pred)
345 : BaseT(Begin, End, Pred) {}
346};
347
348/// Specialization of filter_iterator_base for bidirectional iteration.
349template <typename WrappedIteratorT, typename PredicateT>
350class filter_iterator_impl<WrappedIteratorT, PredicateT,
351 std::bidirectional_iterator_tag>
352 : public filter_iterator_base<WrappedIteratorT, PredicateT,
353 std::bidirectional_iterator_tag> {
354 using BaseT = filter_iterator_base<WrappedIteratorT, PredicateT,
355 std::bidirectional_iterator_tag>;
356 void findPrevValid() {
357 while (!this->Pred(*this->I))
358 BaseT::operator--();
359 }
360
361public:
362 using BaseT::operator--;
363
364 filter_iterator_impl(WrappedIteratorT Begin, WrappedIteratorT End,
365 PredicateT Pred)
366 : BaseT(Begin, End, Pred) {}
367
368 filter_iterator_impl &operator--() {
369 BaseT::operator--();
370 findPrevValid();
371 return *this;
372 }
373};
374
375namespace detail {
376
377template <bool is_bidirectional> struct fwd_or_bidi_tag_impl {
378 using type = std::forward_iterator_tag;
379};
380
381template <> struct fwd_or_bidi_tag_impl<true> {
382 using type = std::bidirectional_iterator_tag;
383};
384
385/// Helper which sets its type member to forward_iterator_tag if the category
386/// of \p IterT does not derive from bidirectional_iterator_tag, and to
387/// bidirectional_iterator_tag otherwise.
388template <typename IterT> struct fwd_or_bidi_tag {
389 using type = typename fwd_or_bidi_tag_impl<std::is_base_of<
390 std::bidirectional_iterator_tag,
391 typename std::iterator_traits<IterT>::iterator_category>::value>::type;
392};
393
394} // namespace detail
395
396/// Defines filter_iterator to a suitable specialization of
397/// filter_iterator_impl, based on the underlying iterator's category.
398template <typename WrappedIteratorT, typename PredicateT>
399using filter_iterator = filter_iterator_impl<
400 WrappedIteratorT, PredicateT,
401 typename detail::fwd_or_bidi_tag<WrappedIteratorT>::type>;
402
403/// Convenience function that takes a range of elements and a predicate,
404/// and return a new filter_iterator range.
405///
406/// FIXME: Currently if RangeT && is a rvalue reference to a temporary, the
407/// lifetime of that temporary is not kept by the returned range object, and the
408/// temporary is going to be dropped on the floor after the make_iterator_range
409/// full expression that contains this function call.
410template <typename RangeT, typename PredicateT>
411iterator_range<filter_iterator<detail::IterOfRange<RangeT>, PredicateT>>
412make_filter_range(RangeT &&Range, PredicateT Pred) {
413 using FilterIteratorT =
414 filter_iterator<detail::IterOfRange<RangeT>, PredicateT>;
415 return make_range(
416 FilterIteratorT(std::begin(std::forward<RangeT>(Range)),
417 std::end(std::forward<RangeT>(Range)), Pred),
418 FilterIteratorT(std::end(std::forward<RangeT>(Range)),
419 std::end(std::forward<RangeT>(Range)), Pred));
420}
421
422/// A pseudo-iterator adaptor that is designed to implement "early increment"
423/// style loops.
424///
425/// This is *not a normal iterator* and should almost never be used directly. It
426/// is intended primarily to be used with range based for loops and some range
427/// algorithms.
428///
429/// The iterator isn't quite an `OutputIterator` or an `InputIterator` but
430/// somewhere between them. The constraints of these iterators are:
431///
432/// - On construction or after being incremented, it is comparable and
433/// dereferencable. It is *not* incrementable.
434/// - After being dereferenced, it is neither comparable nor dereferencable, it
435/// is only incrementable.
436///
437/// This means you can only dereference the iterator once, and you can only
438/// increment it once between dereferences.
439template <typename WrappedIteratorT>
440class early_inc_iterator_impl
441 : public iterator_adaptor_base<early_inc_iterator_impl<WrappedIteratorT>,
442 WrappedIteratorT, std::input_iterator_tag> {
443 using BaseT =
444 iterator_adaptor_base<early_inc_iterator_impl<WrappedIteratorT>,
445 WrappedIteratorT, std::input_iterator_tag>;
446
447 using PointerT = typename std::iterator_traits<WrappedIteratorT>::pointer;
448
449protected:
450#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
451 bool IsEarlyIncremented = false;
452#endif
453
454public:
455 early_inc_iterator_impl(WrappedIteratorT I) : BaseT(I) {}
456
457 using BaseT::operator*;
458 typename BaseT::reference operator*() {
459#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
460 assert(!IsEarlyIncremented && "Cannot dereference twice!")((!IsEarlyIncremented && "Cannot dereference twice!")
? static_cast<void> (0) : __assert_fail ("!IsEarlyIncremented && \"Cannot dereference twice!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/ADT/STLExtras.h"
, 460, __PRETTY_FUNCTION__))
;
461 IsEarlyIncremented = true;
462#endif
463 return *(this->I)++;
464 }
465
466 using BaseT::operator++;
467 early_inc_iterator_impl &operator++() {
468#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
469 assert(IsEarlyIncremented && "Cannot increment before dereferencing!")((IsEarlyIncremented && "Cannot increment before dereferencing!"
) ? static_cast<void> (0) : __assert_fail ("IsEarlyIncremented && \"Cannot increment before dereferencing!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/ADT/STLExtras.h"
, 469, __PRETTY_FUNCTION__))
;
470 IsEarlyIncremented = false;
471#endif
472 return *this;
473 }
474
475 using BaseT::operator==;
476 bool operator==(const early_inc_iterator_impl &RHS) const {
477#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
478 assert(!IsEarlyIncremented && "Cannot compare after dereferencing!")((!IsEarlyIncremented && "Cannot compare after dereferencing!"
) ? static_cast<void> (0) : __assert_fail ("!IsEarlyIncremented && \"Cannot compare after dereferencing!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/ADT/STLExtras.h"
, 478, __PRETTY_FUNCTION__))
;
479#endif
480 return BaseT::operator==(RHS);
481 }
482};
483
484/// Make a range that does early increment to allow mutation of the underlying
485/// range without disrupting iteration.
486///
487/// The underlying iterator will be incremented immediately after it is
488/// dereferenced, allowing deletion of the current node or insertion of nodes to
489/// not disrupt iteration provided they do not invalidate the *next* iterator --
490/// the current iterator can be invalidated.
491///
492/// This requires a very exact pattern of use that is only really suitable to
493/// range based for loops and other range algorithms that explicitly guarantee
494/// to dereference exactly once each element, and to increment exactly once each
495/// element.
496template <typename RangeT>
497iterator_range<early_inc_iterator_impl<detail::IterOfRange<RangeT>>>
498make_early_inc_range(RangeT &&Range) {
499 using EarlyIncIteratorT =
500 early_inc_iterator_impl<detail::IterOfRange<RangeT>>;
501 return make_range(EarlyIncIteratorT(std::begin(std::forward<RangeT>(Range))),
502 EarlyIncIteratorT(std::end(std::forward<RangeT>(Range))));
503}
504
505// forward declarations required by zip_shortest/zip_first
506template <typename R, typename UnaryPredicate>
507bool all_of(R &&range, UnaryPredicate P);
508
509template <size_t... I> struct index_sequence;
510
511template <class... Ts> struct index_sequence_for;
512
513namespace detail {
514
515using std::declval;
516
517// We have to alias this since inlining the actual type at the usage site
518// in the parameter list of iterator_facade_base<> below ICEs MSVC 2017.
519template<typename... Iters> struct ZipTupleType {
520 using type = std::tuple<decltype(*declval<Iters>())...>;
521};
522
523template <typename ZipType, typename... Iters>
524using zip_traits = iterator_facade_base<
525 ZipType, typename std::common_type<std::bidirectional_iterator_tag,
526 typename std::iterator_traits<
527 Iters>::iterator_category...>::type,
528 // ^ TODO: Implement random access methods.
529 typename ZipTupleType<Iters...>::type,
530 typename std::iterator_traits<typename std::tuple_element<
531 0, std::tuple<Iters...>>::type>::difference_type,
532 // ^ FIXME: This follows boost::make_zip_iterator's assumption that all
533 // inner iterators have the same difference_type. It would fail if, for
534 // instance, the second field's difference_type were non-numeric while the
535 // first is.
536 typename ZipTupleType<Iters...>::type *,
537 typename ZipTupleType<Iters...>::type>;
538
539template <typename ZipType, typename... Iters>
540struct zip_common : public zip_traits<ZipType, Iters...> {
541 using Base = zip_traits<ZipType, Iters...>;
542 using value_type = typename Base::value_type;
543
544 std::tuple<Iters...> iterators;
545
546protected:
547 template <size_t... Ns> value_type deref(index_sequence<Ns...>) const {
548 return value_type(*std::get<Ns>(iterators)...);
549 }
550
551 template <size_t... Ns>
552 decltype(iterators) tup_inc(index_sequence<Ns...>) const {
553 return std::tuple<Iters...>(std::next(std::get<Ns>(iterators))...);
554 }
555
556 template <size_t... Ns>
557 decltype(iterators) tup_dec(index_sequence<Ns...>) const {
558 return std::tuple<Iters...>(std::prev(std::get<Ns>(iterators))...);
559 }
560
561public:
562 zip_common(Iters &&... ts) : iterators(std::forward<Iters>(ts)...) {}
563
564 value_type operator*() { return deref(index_sequence_for<Iters...>{}); }
565
566 const value_type operator*() const {
567 return deref(index_sequence_for<Iters...>{});
568 }
569
570 ZipType &operator++() {
571 iterators = tup_inc(index_sequence_for<Iters...>{});
572 return *reinterpret_cast<ZipType *>(this);
573 }
574
575 ZipType &operator--() {
576 static_assert(Base::IsBidirectional,
577 "All inner iterators must be at least bidirectional.");
578 iterators = tup_dec(index_sequence_for<Iters...>{});
579 return *reinterpret_cast<ZipType *>(this);
580 }
581};
582
583template <typename... Iters>
584struct zip_first : public zip_common<zip_first<Iters...>, Iters...> {
585 using Base = zip_common<zip_first<Iters...>, Iters...>;
586
587 bool operator==(const zip_first<Iters...> &other) const {
588 return std::get<0>(this->iterators) == std::get<0>(other.iterators);
589 }
590
591 zip_first(Iters &&... ts) : Base(std::forward<Iters>(ts)...) {}
592};
593
594template <typename... Iters>
595class zip_shortest : public zip_common<zip_shortest<Iters...>, Iters...> {
596 template <size_t... Ns>
597 bool test(const zip_shortest<Iters...> &other, index_sequence<Ns...>) const {
598 return all_of(std::initializer_list<bool>{std::get<Ns>(this->iterators) !=
599 std::get<Ns>(other.iterators)...},
600 identity<bool>{});
601 }
602
603public:
604 using Base = zip_common<zip_shortest<Iters...>, Iters...>;
605
606 zip_shortest(Iters &&... ts) : Base(std::forward<Iters>(ts)...) {}
607
608 bool operator==(const zip_shortest<Iters...> &other) const {
609 return !test(other, index_sequence_for<Iters...>{});
610 }
611};
612
613template <template <typename...> class ItType, typename... Args> class zippy {
614public:
615 using iterator = ItType<decltype(std::begin(std::declval<Args>()))...>;
616 using iterator_category = typename iterator::iterator_category;
617 using value_type = typename iterator::value_type;
618 using difference_type = typename iterator::difference_type;
619 using pointer = typename iterator::pointer;
620 using reference = typename iterator::reference;
621
622private:
623 std::tuple<Args...> ts;
624
625 template <size_t... Ns> iterator begin_impl(index_sequence<Ns...>) const {
626 return iterator(std::begin(std::get<Ns>(ts))...);
627 }
628 template <size_t... Ns> iterator end_impl(index_sequence<Ns...>) const {
629 return iterator(std::end(std::get<Ns>(ts))...);
630 }
631
632public:
633 zippy(Args &&... ts_) : ts(std::forward<Args>(ts_)...) {}
634
635 iterator begin() const { return begin_impl(index_sequence_for<Args...>{}); }
636 iterator end() const { return end_impl(index_sequence_for<Args...>{}); }
637};
638
639} // end namespace detail
640
641/// zip iterator for two or more iteratable types.
642template <typename T, typename U, typename... Args>
643detail::zippy<detail::zip_shortest, T, U, Args...> zip(T &&t, U &&u,
644 Args &&... args) {
645 return detail::zippy<detail::zip_shortest, T, U, Args...>(
646 std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
647}
648
649/// zip iterator that, for the sake of efficiency, assumes the first iteratee to
650/// be the shortest.
651template <typename T, typename U, typename... Args>
652detail::zippy<detail::zip_first, T, U, Args...> zip_first(T &&t, U &&u,
653 Args &&... args) {
654 return detail::zippy<detail::zip_first, T, U, Args...>(
655 std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
656}
657
658/// Iterator wrapper that concatenates sequences together.
659///
660/// This can concatenate different iterators, even with different types, into
661/// a single iterator provided the value types of all the concatenated
662/// iterators expose `reference` and `pointer` types that can be converted to
663/// `ValueT &` and `ValueT *` respectively. It doesn't support more
664/// interesting/customized pointer or reference types.
665///
666/// Currently this only supports forward or higher iterator categories as
667/// inputs and always exposes a forward iterator interface.
668template <typename ValueT, typename... IterTs>
669class concat_iterator
670 : public iterator_facade_base<concat_iterator<ValueT, IterTs...>,
671 std::forward_iterator_tag, ValueT> {
672 using BaseT = typename concat_iterator::iterator_facade_base;
673
674 /// We store both the current and end iterators for each concatenated
675 /// sequence in a tuple of pairs.
676 ///
677 /// Note that something like iterator_range seems nice at first here, but the
678 /// range properties are of little benefit and end up getting in the way
679 /// because we need to do mutation on the current iterators.
680 std::tuple<IterTs...> Begins;
681 std::tuple<IterTs...> Ends;
682
683 /// Attempts to increment a specific iterator.
684 ///
685 /// Returns true if it was able to increment the iterator. Returns false if
686 /// the iterator is already at the end iterator.
687 template <size_t Index> bool incrementHelper() {
688 auto &Begin = std::get<Index>(Begins);
689 auto &End = std::get<Index>(Ends);
690 if (Begin == End)
691 return false;
692
693 ++Begin;
694 return true;
695 }
696
697 /// Increments the first non-end iterator.
698 ///
699 /// It is an error to call this with all iterators at the end.
700 template <size_t... Ns> void increment(index_sequence<Ns...>) {
701 // Build a sequence of functions to increment each iterator if possible.
702 bool (concat_iterator::*IncrementHelperFns[])() = {
703 &concat_iterator::incrementHelper<Ns>...};
704
705 // Loop over them, and stop as soon as we succeed at incrementing one.
706 for (auto &IncrementHelperFn : IncrementHelperFns)
707 if ((this->*IncrementHelperFn)())
708 return;
709
710 llvm_unreachable("Attempted to increment an end concat iterator!")::llvm::llvm_unreachable_internal("Attempted to increment an end concat iterator!"
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/ADT/STLExtras.h"
, 710)
;
711 }
712
713 /// Returns null if the specified iterator is at the end. Otherwise,
714 /// dereferences the iterator and returns the address of the resulting
715 /// reference.
716 template <size_t Index> ValueT *getHelper() const {
717 auto &Begin = std::get<Index>(Begins);
718 auto &End = std::get<Index>(Ends);
719 if (Begin == End)
720 return nullptr;
721
722 return &*Begin;
723 }
724
725 /// Finds the first non-end iterator, dereferences, and returns the resulting
726 /// reference.
727 ///
728 /// It is an error to call this with all iterators at the end.
729 template <size_t... Ns> ValueT &get(index_sequence<Ns...>) const {
730 // Build a sequence of functions to get from iterator if possible.
731 ValueT *(concat_iterator::*GetHelperFns[])() const = {
732 &concat_iterator::getHelper<Ns>...};
733
734 // Loop over them, and return the first result we find.
735 for (auto &GetHelperFn : GetHelperFns)
736 if (ValueT *P = (this->*GetHelperFn)())
737 return *P;
738
739 llvm_unreachable("Attempted to get a pointer from an end concat iterator!")::llvm::llvm_unreachable_internal("Attempted to get a pointer from an end concat iterator!"
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/ADT/STLExtras.h"
, 739)
;
740 }
741
742public:
743 /// Constructs an iterator from a squence of ranges.
744 ///
745 /// We need the full range to know how to switch between each of the
746 /// iterators.
747 template <typename... RangeTs>
748 explicit concat_iterator(RangeTs &&... Ranges)
749 : Begins(std::begin(Ranges)...), Ends(std::end(Ranges)...) {}
750
751 using BaseT::operator++;
752
753 concat_iterator &operator++() {
754 increment(index_sequence_for<IterTs...>());
755 return *this;
756 }
757
758 ValueT &operator*() const { return get(index_sequence_for<IterTs...>()); }
759
760 bool operator==(const concat_iterator &RHS) const {
761 return Begins == RHS.Begins && Ends == RHS.Ends;
762 }
763};
764
765namespace detail {
766
767/// Helper to store a sequence of ranges being concatenated and access them.
768///
769/// This is designed to facilitate providing actual storage when temporaries
770/// are passed into the constructor such that we can use it as part of range
771/// based for loops.
772template <typename ValueT, typename... RangeTs> class concat_range {
773public:
774 using iterator =
775 concat_iterator<ValueT,
776 decltype(std::begin(std::declval<RangeTs &>()))...>;
777
778private:
779 std::tuple<RangeTs...> Ranges;
780
781 template <size_t... Ns> iterator begin_impl(index_sequence<Ns...>) {
782 return iterator(std::get<Ns>(Ranges)...);
783 }
784 template <size_t... Ns> iterator end_impl(index_sequence<Ns...>) {
785 return iterator(make_range(std::end(std::get<Ns>(Ranges)),
786 std::end(std::get<Ns>(Ranges)))...);
787 }
788
789public:
790 concat_range(RangeTs &&... Ranges)
791 : Ranges(std::forward<RangeTs>(Ranges)...) {}
792
793 iterator begin() { return begin_impl(index_sequence_for<RangeTs...>{}); }
794 iterator end() { return end_impl(index_sequence_for<RangeTs...>{}); }
795};
796
797} // end namespace detail
798
799/// Concatenated range across two or more ranges.
800///
801/// The desired value type must be explicitly specified.
802template <typename ValueT, typename... RangeTs>
803detail::concat_range<ValueT, RangeTs...> concat(RangeTs &&... Ranges) {
804 static_assert(sizeof...(RangeTs) > 1,
805 "Need more than one range to concatenate!");
806 return detail::concat_range<ValueT, RangeTs...>(
807 std::forward<RangeTs>(Ranges)...);
808}
809
810//===----------------------------------------------------------------------===//
811// Extra additions to <utility>
812//===----------------------------------------------------------------------===//
813
814/// Function object to check whether the first component of a std::pair
815/// compares less than the first component of another std::pair.
816struct less_first {
817 template <typename T> bool operator()(const T &lhs, const T &rhs) const {
818 return lhs.first < rhs.first;
819 }
820};
821
822/// Function object to check whether the second component of a std::pair
823/// compares less than the second component of another std::pair.
824struct less_second {
825 template <typename T> bool operator()(const T &lhs, const T &rhs) const {
826 return lhs.second < rhs.second;
827 }
828};
829
830/// \brief Function object to apply a binary function to the first component of
831/// a std::pair.
832template<typename FuncTy>
833struct on_first {
834 FuncTy func;
835
836 template <typename T>
837 auto operator()(const T &lhs, const T &rhs) const
838 -> decltype(func(lhs.first, rhs.first)) {
839 return func(lhs.first, rhs.first);
840 }
841};
842
843// A subset of N3658. More stuff can be added as-needed.
844
845/// Represents a compile-time sequence of integers.
846template <class T, T... I> struct integer_sequence {
847 using value_type = T;
848
849 static constexpr size_t size() { return sizeof...(I); }
850};
851
852/// Alias for the common case of a sequence of size_ts.
853template <size_t... I>
854struct index_sequence : integer_sequence<std::size_t, I...> {};
855
856template <std::size_t N, std::size_t... I>
857struct build_index_impl : build_index_impl<N - 1, N - 1, I...> {};
858template <std::size_t... I>
859struct build_index_impl<0, I...> : index_sequence<I...> {};
860
861/// Creates a compile-time integer sequence for a parameter pack.
862template <class... Ts>
863struct index_sequence_for : build_index_impl<sizeof...(Ts)> {};
864
865/// Utility type to build an inheritance chain that makes it easy to rank
866/// overload candidates.
867template <int N> struct rank : rank<N - 1> {};
868template <> struct rank<0> {};
869
870/// traits class for checking whether type T is one of any of the given
871/// types in the variadic list.
872template <typename T, typename... Ts> struct is_one_of {
873 static const bool value = false;
874};
875
876template <typename T, typename U, typename... Ts>
877struct is_one_of<T, U, Ts...> {
878 static const bool value =
879 std::is_same<T, U>::value || is_one_of<T, Ts...>::value;
880};
881
882/// traits class for checking whether type T is a base class for all
883/// the given types in the variadic list.
884template <typename T, typename... Ts> struct are_base_of {
885 static const bool value = true;
886};
887
888template <typename T, typename U, typename... Ts>
889struct are_base_of<T, U, Ts...> {
890 static const bool value =
891 std::is_base_of<T, U>::value && are_base_of<T, Ts...>::value;
892};
893
894//===----------------------------------------------------------------------===//
895// Extra additions for arrays
896//===----------------------------------------------------------------------===//
897
898/// Find the length of an array.
899template <class T, std::size_t N>
900constexpr inline size_t array_lengthof(T (&)[N]) {
901 return N;
902}
903
904/// Adapt std::less<T> for array_pod_sort.
905template<typename T>
906inline int array_pod_sort_comparator(const void *P1, const void *P2) {
907 if (std::less<T>()(*reinterpret_cast<const T*>(P1),
908 *reinterpret_cast<const T*>(P2)))
909 return -1;
910 if (std::less<T>()(*reinterpret_cast<const T*>(P2),
911 *reinterpret_cast<const T*>(P1)))
912 return 1;
913 return 0;
914}
915
916/// get_array_pod_sort_comparator - This is an internal helper function used to
917/// get type deduction of T right.
918template<typename T>
919inline int (*get_array_pod_sort_comparator(const T &))
920 (const void*, const void*) {
921 return array_pod_sort_comparator<T>;
922}
923
924/// array_pod_sort - This sorts an array with the specified start and end
925/// extent. This is just like std::sort, except that it calls qsort instead of
926/// using an inlined template. qsort is slightly slower than std::sort, but
927/// most sorts are not performance critical in LLVM and std::sort has to be
928/// template instantiated for each type, leading to significant measured code
929/// bloat. This function should generally be used instead of std::sort where
930/// possible.
931///
932/// This function assumes that you have simple POD-like types that can be
933/// compared with std::less and can be moved with memcpy. If this isn't true,
934/// you should use std::sort.
935///
936/// NOTE: If qsort_r were portable, we could allow a custom comparator and
937/// default to std::less.
938template<class IteratorTy>
939inline void array_pod_sort(IteratorTy Start, IteratorTy End) {
940 // Don't inefficiently call qsort with one element or trigger undefined
941 // behavior with an empty sequence.
942 auto NElts = End - Start;
943 if (NElts <= 1) return;
944#ifdef EXPENSIVE_CHECKS
945 std::mt19937 Generator(std::random_device{}());
946 std::shuffle(Start, End, Generator);
947#endif
948 qsort(&*Start, NElts, sizeof(*Start), get_array_pod_sort_comparator(*Start));
949}
950
951template <class IteratorTy>
952inline void array_pod_sort(
953 IteratorTy Start, IteratorTy End,
954 int (*Compare)(
955 const typename std::iterator_traits<IteratorTy>::value_type *,
956 const typename std::iterator_traits<IteratorTy>::value_type *)) {
957 // Don't inefficiently call qsort with one element or trigger undefined
958 // behavior with an empty sequence.
959 auto NElts = End - Start;
960 if (NElts <= 1) return;
961#ifdef EXPENSIVE_CHECKS
962 std::mt19937 Generator(std::random_device{}());
963 std::shuffle(Start, End, Generator);
964#endif
965 qsort(&*Start, NElts, sizeof(*Start),
966 reinterpret_cast<int (*)(const void *, const void *)>(Compare));
967}
968
969// Provide wrappers to std::sort which shuffle the elements before sorting
970// to help uncover non-deterministic behavior (PR35135).
971template <typename IteratorTy>
972inline void sort(IteratorTy Start, IteratorTy End) {
973#ifdef EXPENSIVE_CHECKS
974 std::mt19937 Generator(std::random_device{}());
975 std::shuffle(Start, End, Generator);
976#endif
977 std::sort(Start, End);
978}
979
980template <typename Container> inline void sort(Container &&C) {
981 llvm::sort(adl_begin(C), adl_end(C));
982}
983
984template <typename IteratorTy, typename Compare>
985inline void sort(IteratorTy Start, IteratorTy End, Compare Comp) {
986#ifdef EXPENSIVE_CHECKS
987 std::mt19937 Generator(std::random_device{}());
988 std::shuffle(Start, End, Generator);
989#endif
990 std::sort(Start, End, Comp);
991}
992
993template <typename Container, typename Compare>
994inline void sort(Container &&C, Compare Comp) {
995 llvm::sort(adl_begin(C), adl_end(C), Comp);
996}
997
998//===----------------------------------------------------------------------===//
999// Extra additions to <algorithm>
1000//===----------------------------------------------------------------------===//
1001
1002/// For a container of pointers, deletes the pointers and then clears the
1003/// container.
1004template<typename Container>
1005void DeleteContainerPointers(Container &C) {
1006 for (auto V : C)
1007 delete V;
1008 C.clear();
1009}
1010
1011/// In a container of pairs (usually a map) whose second element is a pointer,
1012/// deletes the second elements and then clears the container.
1013template<typename Container>
1014void DeleteContainerSeconds(Container &C) {
1015 for (auto &V : C)
1016 delete V.second;
1017 C.clear();
1018}
1019
1020/// Get the size of a range. This is a wrapper function around std::distance
1021/// which is only enabled when the operation is O(1).
1022template <typename R>
1023auto size(R &&Range, typename std::enable_if<
1024 std::is_same<typename std::iterator_traits<decltype(
1025 Range.begin())>::iterator_category,
1026 std::random_access_iterator_tag>::value,
1027 void>::type * = nullptr)
1028 -> decltype(std::distance(Range.begin(), Range.end())) {
1029 return std::distance(Range.begin(), Range.end());
1030}
1031
1032/// Provide wrappers to std::for_each which take ranges instead of having to
1033/// pass begin/end explicitly.
1034template <typename R, typename UnaryPredicate>
1035UnaryPredicate for_each(R &&Range, UnaryPredicate P) {
1036 return std::for_each(adl_begin(Range), adl_end(Range), P);
1037}
1038
1039/// Provide wrappers to std::all_of which take ranges instead of having to pass
1040/// begin/end explicitly.
1041template <typename R, typename UnaryPredicate>
1042bool all_of(R &&Range, UnaryPredicate P) {
1043 return std::all_of(adl_begin(Range), adl_end(Range), P);
1044}
1045
1046/// Provide wrappers to std::any_of which take ranges instead of having to pass
1047/// begin/end explicitly.
1048template <typename R, typename UnaryPredicate>
1049bool any_of(R &&Range, UnaryPredicate P) {
1050 return std::any_of(adl_begin(Range), adl_end(Range), P);
1051}
1052
1053/// Provide wrappers to std::none_of which take ranges instead of having to pass
1054/// begin/end explicitly.
1055template <typename R, typename UnaryPredicate>
1056bool none_of(R &&Range, UnaryPredicate P) {
1057 return std::none_of(adl_begin(Range), adl_end(Range), P);
1058}
1059
1060/// Provide wrappers to std::find which take ranges instead of having to pass
1061/// begin/end explicitly.
1062template <typename R, typename T>
1063auto find(R &&Range, const T &Val) -> decltype(adl_begin(Range)) {
1064 return std::find(adl_begin(Range), adl_end(Range), Val);
1065}
1066
1067/// Provide wrappers to std::find_if which take ranges instead of having to pass
1068/// begin/end explicitly.
1069template <typename R, typename UnaryPredicate>
1070auto find_if(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
1071 return std::find_if(adl_begin(Range), adl_end(Range), P);
1072}
1073
1074template <typename R, typename UnaryPredicate>
1075auto find_if_not(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
1076 return std::find_if_not(adl_begin(Range), adl_end(Range), P);
1077}
1078
1079/// Provide wrappers to std::remove_if which take ranges instead of having to
1080/// pass begin/end explicitly.
1081template <typename R, typename UnaryPredicate>
1082auto remove_if(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
1083 return std::remove_if(adl_begin(Range), adl_end(Range), P);
1084}
1085
1086/// Provide wrappers to std::copy_if which take ranges instead of having to
1087/// pass begin/end explicitly.
1088template <typename R, typename OutputIt, typename UnaryPredicate>
1089OutputIt copy_if(R &&Range, OutputIt Out, UnaryPredicate P) {
1090 return std::copy_if(adl_begin(Range), adl_end(Range), Out, P);
1091}
1092
1093template <typename R, typename OutputIt>
1094OutputIt copy(R &&Range, OutputIt Out) {
1095 return std::copy(adl_begin(Range), adl_end(Range), Out);
1096}
1097
1098/// Wrapper function around std::find to detect if an element exists
1099/// in a container.
1100template <typename R, typename E>
1101bool is_contained(R &&Range, const E &Element) {
1102 return std::find(adl_begin(Range), adl_end(Range), Element) != adl_end(Range);
1103}
1104
1105/// Wrapper function around std::count to count the number of times an element
1106/// \p Element occurs in the given range \p Range.
1107template <typename R, typename E>
1108auto count(R &&Range, const E &Element) ->
1109 typename std::iterator_traits<decltype(adl_begin(Range))>::difference_type {
1110 return std::count(adl_begin(Range), adl_end(Range), Element);
1111}
1112
1113/// Wrapper function around std::count_if to count the number of times an
1114/// element satisfying a given predicate occurs in a range.
1115template <typename R, typename UnaryPredicate>
1116auto count_if(R &&Range, UnaryPredicate P) ->
1117 typename std::iterator_traits<decltype(adl_begin(Range))>::difference_type {
1118 return std::count_if(adl_begin(Range), adl_end(Range), P);
1119}
1120
1121/// Wrapper function around std::transform to apply a function to a range and
1122/// store the result elsewhere.
1123template <typename R, typename OutputIt, typename UnaryPredicate>
1124OutputIt transform(R &&Range, OutputIt d_first, UnaryPredicate P) {
1125 return std::transform(adl_begin(Range), adl_end(Range), d_first, P);
1126}
1127
1128/// Provide wrappers to std::partition which take ranges instead of having to
1129/// pass begin/end explicitly.
1130template <typename R, typename UnaryPredicate>
1131auto partition(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
1132 return std::partition(adl_begin(Range), adl_end(Range), P);
1133}
1134
1135/// Provide wrappers to std::lower_bound which take ranges instead of having to
1136/// pass begin/end explicitly.
1137template <typename R, typename ForwardIt>
1138auto lower_bound(R &&Range, ForwardIt I) -> decltype(adl_begin(Range)) {
1139 return std::lower_bound(adl_begin(Range), adl_end(Range), I);
1140}
1141
1142template <typename R, typename ForwardIt, typename Compare>
1143auto lower_bound(R &&Range, ForwardIt I, Compare C)
1144 -> decltype(adl_begin(Range)) {
1145 return std::lower_bound(adl_begin(Range), adl_end(Range), I, C);
1146}
1147
1148/// Provide wrappers to std::upper_bound which take ranges instead of having to
1149/// pass begin/end explicitly.
1150template <typename R, typename ForwardIt>
1151auto upper_bound(R &&Range, ForwardIt I) -> decltype(adl_begin(Range)) {
1152 return std::upper_bound(adl_begin(Range), adl_end(Range), I);
1153}
1154
1155template <typename R, typename ForwardIt, typename Compare>
1156auto upper_bound(R &&Range, ForwardIt I, Compare C)
1157 -> decltype(adl_begin(Range)) {
1158 return std::upper_bound(adl_begin(Range), adl_end(Range), I, C);
1159}
1160/// Wrapper function around std::equal to detect if all elements
1161/// in a container are same.
1162template <typename R>
1163bool is_splat(R &&Range) {
1164 size_t range_size = size(Range);
1165 return range_size != 0 && (range_size == 1 ||
1166 std::equal(adl_begin(Range) + 1, adl_end(Range), adl_begin(Range)));
1167}
1168
1169/// Given a range of type R, iterate the entire range and return a
1170/// SmallVector with elements of the vector. This is useful, for example,
1171/// when you want to iterate a range and then sort the results.
1172template <unsigned Size, typename R>
1173SmallVector<typename std::remove_const<detail::ValueOfRange<R>>::type, Size>
1174to_vector(R &&Range) {
1175 return {adl_begin(Range), adl_end(Range)};
1176}
1177
1178/// Provide a container algorithm similar to C++ Library Fundamentals v2's
1179/// `erase_if` which is equivalent to:
1180///
1181/// C.erase(remove_if(C, pred), C.end());
1182///
1183/// This version works for any container with an erase method call accepting
1184/// two iterators.
1185template <typename Container, typename UnaryPredicate>
1186void erase_if(Container &C, UnaryPredicate P) {
1187 C.erase(remove_if(C, P), C.end());
1188}
1189
1190//===----------------------------------------------------------------------===//
1191// Extra additions to <memory>
1192//===----------------------------------------------------------------------===//
1193
1194// Implement make_unique according to N3656.
1195
1196/// Constructs a `new T()` with the given args and returns a
1197/// `unique_ptr<T>` which owns the object.
1198///
1199/// Example:
1200///
1201/// auto p = make_unique<int>();
1202/// auto p = make_unique<std::tuple<int, int>>(0, 1);
1203template <class T, class... Args>
1204typename std::enable_if<!std::is_array<T>::value, std::unique_ptr<T>>::type
1205make_unique(Args &&... args) {
1206 return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
4
Memory is allocated
1207}
1208
1209/// Constructs a `new T[n]` with the given args and returns a
1210/// `unique_ptr<T[]>` which owns the object.
1211///
1212/// \param n size of the new array.
1213///
1214/// Example:
1215///
1216/// auto p = make_unique<int[]>(2); // value-initializes the array with 0's.
1217template <class T>
1218typename std::enable_if<std::is_array<T>::value && std::extent<T>::value == 0,
1219 std::unique_ptr<T>>::type
1220make_unique(size_t n) {
1221 return std::unique_ptr<T>(new typename std::remove_extent<T>::type[n]());
1222}
1223
1224/// This function isn't used and is only here to provide better compile errors.
1225template <class T, class... Args>
1226typename std::enable_if<std::extent<T>::value != 0>::type
1227make_unique(Args &&...) = delete;
1228
1229struct FreeDeleter {
1230 void operator()(void* v) {
1231 ::free(v);
1232 }
1233};
1234
1235template<typename First, typename Second>
1236struct pair_hash {
1237 size_t operator()(const std::pair<First, Second> &P) const {
1238 return std::hash<First>()(P.first) * 31 + std::hash<Second>()(P.second);
1239 }
1240};
1241
1242/// A functor like C++14's std::less<void> in its absence.
1243struct less {
1244 template <typename A, typename B> bool operator()(A &&a, B &&b) const {
1245 return std::forward<A>(a) < std::forward<B>(b);
1246 }
1247};
1248
1249/// A functor like C++14's std::equal<void> in its absence.
1250struct equal {
1251 template <typename A, typename B> bool operator()(A &&a, B &&b) const {
1252 return std::forward<A>(a) == std::forward<B>(b);
1253 }
1254};
1255
1256/// Binary functor that adapts to any other binary functor after dereferencing
1257/// operands.
1258template <typename T> struct deref {
1259 T func;
1260
1261 // Could be further improved to cope with non-derivable functors and
1262 // non-binary functors (should be a variadic template member function
1263 // operator()).
1264 template <typename A, typename B>
1265 auto operator()(A &lhs, B &rhs) const -> decltype(func(*lhs, *rhs)) {
1266 assert(lhs)((lhs) ? static_cast<void> (0) : __assert_fail ("lhs", "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/ADT/STLExtras.h"
, 1266, __PRETTY_FUNCTION__))
;
1267 assert(rhs)((rhs) ? static_cast<void> (0) : __assert_fail ("rhs", "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/ADT/STLExtras.h"
, 1267, __PRETTY_FUNCTION__))
;
1268 return func(*lhs, *rhs);
1269 }
1270};
1271
1272namespace detail {
1273
1274template <typename R> class enumerator_iter;
1275
1276template <typename R> struct result_pair {
1277 friend class enumerator_iter<R>;
1278
1279 result_pair() = default;
1280 result_pair(std::size_t Index, IterOfRange<R> Iter)
1281 : Index(Index), Iter(Iter) {}
1282
1283 result_pair<R> &operator=(const result_pair<R> &Other) {
1284 Index = Other.Index;
1285 Iter = Other.Iter;
1286 return *this;
1287 }
1288
1289 std::size_t index() const { return Index; }
1290 const ValueOfRange<R> &value() const { return *Iter; }
1291 ValueOfRange<R> &value() { return *Iter; }
1292
1293private:
1294 std::size_t Index = std::numeric_limits<std::size_t>::max();
1295 IterOfRange<R> Iter;
1296};
1297
1298template <typename R>
1299class enumerator_iter
1300 : public iterator_facade_base<
1301 enumerator_iter<R>, std::forward_iterator_tag, result_pair<R>,
1302 typename std::iterator_traits<IterOfRange<R>>::difference_type,
1303 typename std::iterator_traits<IterOfRange<R>>::pointer,
1304 typename std::iterator_traits<IterOfRange<R>>::reference> {
1305 using result_type = result_pair<R>;
1306
1307public:
1308 explicit enumerator_iter(IterOfRange<R> EndIter)
1309 : Result(std::numeric_limits<size_t>::max(), EndIter) {}
1310
1311 enumerator_iter(std::size_t Index, IterOfRange<R> Iter)
1312 : Result(Index, Iter) {}
1313
1314 result_type &operator*() { return Result; }
1315 const result_type &operator*() const { return Result; }
1316
1317 enumerator_iter<R> &operator++() {
1318 assert(Result.Index != std::numeric_limits<size_t>::max())((Result.Index != std::numeric_limits<size_t>::max()) ?
static_cast<void> (0) : __assert_fail ("Result.Index != std::numeric_limits<size_t>::max()"
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/ADT/STLExtras.h"
, 1318, __PRETTY_FUNCTION__))
;
1319 ++Result.Iter;
1320 ++Result.Index;
1321 return *this;
1322 }
1323
1324 bool operator==(const enumerator_iter<R> &RHS) const {
1325 // Don't compare indices here, only iterators. It's possible for an end
1326 // iterator to have different indices depending on whether it was created
1327 // by calling std::end() versus incrementing a valid iterator.
1328 return Result.Iter == RHS.Result.Iter;
1329 }
1330
1331 enumerator_iter<R> &operator=(const enumerator_iter<R> &Other) {
1332 Result = Other.Result;
1333 return *this;
1334 }
1335
1336private:
1337 result_type Result;
1338};
1339
1340template <typename R> class enumerator {
1341public:
1342 explicit enumerator(R &&Range) : TheRange(std::forward<R>(Range)) {}
1343
1344 enumerator_iter<R> begin() {
1345 return enumerator_iter<R>(0, std::begin(TheRange));
1346 }
1347
1348 enumerator_iter<R> end() {
1349 return enumerator_iter<R>(std::end(TheRange));
1350 }
1351
1352private:
1353 R TheRange;
1354};
1355
1356} // end namespace detail
1357
1358/// Given an input range, returns a new range whose values are are pair (A,B)
1359/// such that A is the 0-based index of the item in the sequence, and B is
1360/// the value from the original sequence. Example:
1361///
1362/// std::vector<char> Items = {'A', 'B', 'C', 'D'};
1363/// for (auto X : enumerate(Items)) {
1364/// printf("Item %d - %c\n", X.index(), X.value());
1365/// }
1366///
1367/// Output:
1368/// Item 0 - A
1369/// Item 1 - B
1370/// Item 2 - C
1371/// Item 3 - D
1372///
1373template <typename R> detail::enumerator<R> enumerate(R &&TheRange) {
1374 return detail::enumerator<R>(std::forward<R>(TheRange));
1375}
1376
1377namespace detail {
1378
1379template <typename F, typename Tuple, std::size_t... I>
1380auto apply_tuple_impl(F &&f, Tuple &&t, index_sequence<I...>)
1381 -> decltype(std::forward<F>(f)(std::get<I>(std::forward<Tuple>(t))...)) {
1382 return std::forward<F>(f)(std::get<I>(std::forward<Tuple>(t))...);
1383}
1384
1385} // end namespace detail
1386
1387/// Given an input tuple (a1, a2, ..., an), pass the arguments of the
1388/// tuple variadically to f as if by calling f(a1, a2, ..., an) and
1389/// return the result.
1390template <typename F, typename Tuple>
1391auto apply_tuple(F &&f, Tuple &&t) -> decltype(detail::apply_tuple_impl(
1392 std::forward<F>(f), std::forward<Tuple>(t),
1393 build_index_impl<
1394 std::tuple_size<typename std::decay<Tuple>::type>::value>{})) {
1395 using Indices = build_index_impl<
1396 std::tuple_size<typename std::decay<Tuple>::type>::value>;
1397
1398 return detail::apply_tuple_impl(std::forward<F>(f), std::forward<Tuple>(t),
1399 Indices{});
1400}
1401
1402} // end namespace llvm
1403
1404#endif // LLVM_ADT_STLEXTRAS_H