Bug Summary

File:tools/lli/ChildTarget/ChildTarget.cpp
Warning:line 900, column 33
2nd function call argument is an uninitialized value

Annotated Source Code

/build/llvm-toolchain-snapshot-6.0~svn318693/tools/lli/ChildTarget/ChildTarget.cpp

1#include "llvm/ExecutionEngine/Orc/OrcABISupport.h"
2#include "llvm/ExecutionEngine/Orc/OrcRemoteTargetServer.h"
3#include "llvm/Support/Debug.h"
4#include "llvm/Support/DynamicLibrary.h"
5#include "llvm/Support/Process.h"
6#include <sstream>
7
8#include "../RemoteJITUtils.h"
9
10using namespace llvm;
11using namespace llvm::orc;
12using namespace llvm::sys;
13
14#ifdef __x86_64__1
15typedef OrcX86_64_SysV HostOrcArch;
16#else
17typedef OrcGenericABI HostOrcArch;
18#endif
19
20ExitOnError ExitOnErr;
21
22int main(int argc, char *argv[]) {
23
24 if (argc != 3) {
1
Assuming 'argc' is equal to 3
2
Taking false branch
25 errs() << "Usage: " << argv[0] << " <input fd> <output fd>\n";
26 return 1;
27 }
28
29 ExitOnErr.setBanner(std::string(argv[0]) + ":");
30
31 int InFD;
32 int OutFD;
33 {
34 std::istringstream InFDStream(argv[1]), OutFDStream(argv[2]);
35 InFDStream >> InFD;
36 OutFDStream >> OutFD;
37 }
38
39 if (sys::DynamicLibrary::LoadLibraryPermanently(nullptr)) {
3
Taking false branch
40 errs() << "Error loading program symbols.\n";
41 return 1;
42 }
43
44 auto SymbolLookup = [](const std::string &Name) {
45 return RTDyldMemoryManager::getSymbolAddressInProcess(Name);
46 };
47
48 auto RegisterEHFrames = [](uint8_t *Addr, uint32_t Size) {
49 RTDyldMemoryManager::registerEHFramesInProcess(Addr, Size);
50 };
51
52 auto DeregisterEHFrames = [](uint8_t *Addr, uint32_t Size) {
53 RTDyldMemoryManager::deregisterEHFramesInProcess(Addr, Size);
54 };
55
56 FDRawChannel Channel(InFD, OutFD);
57 typedef remote::OrcRemoteTargetServer<FDRawChannel, HostOrcArch> JITServer;
58 JITServer Server(Channel, SymbolLookup, RegisterEHFrames, DeregisterEHFrames);
59
60 while (!Server.receivedTerminate())
4
Assuming the condition is true
5
Loop condition is true. Entering loop body
61 ExitOnErr(Server.handleOne());
6
Calling 'RPCEndpointBase::handleOne'
62
63 close(InFD);
64 close(OutFD);
65
66 return 0;
67}

/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/ExecutionEngine/Orc/RPCUtils.h

1//===------- RPCUTils.h - Utilities for building RPC APIs -------*- 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// Utilities to support construction of simple RPC APIs.
11//
12// The RPC utilities aim for ease of use (minimal conceptual overhead) for C++
13// programmers, high performance, low memory overhead, and efficient use of the
14// communications channel.
15//
16//===----------------------------------------------------------------------===//
17
18#ifndef LLVM_EXECUTIONENGINE_ORC_RPCUTILS_H
19#define LLVM_EXECUTIONENGINE_ORC_RPCUTILS_H
20
21#include <map>
22#include <thread>
23#include <vector>
24
25#include "llvm/ADT/STLExtras.h"
26#include "llvm/ExecutionEngine/Orc/OrcError.h"
27#include "llvm/ExecutionEngine/Orc/RPCSerialization.h"
28
29#include <future>
30
31namespace llvm {
32namespace orc {
33namespace rpc {
34
35/// Base class of all fatal RPC errors (those that necessarily result in the
36/// termination of the RPC session).
37class RPCFatalError : public ErrorInfo<RPCFatalError> {
38public:
39 static char ID;
40};
41
42/// RPCConnectionClosed is returned from RPC operations if the RPC connection
43/// has already been closed due to either an error or graceful disconnection.
44class ConnectionClosed : public ErrorInfo<ConnectionClosed> {
45public:
46 static char ID;
47 std::error_code convertToErrorCode() const override;
48 void log(raw_ostream &OS) const override;
49};
50
51/// BadFunctionCall is returned from handleOne when the remote makes a call with
52/// an unrecognized function id.
53///
54/// This error is fatal because Orc RPC needs to know how to parse a function
55/// call to know where the next call starts, and if it doesn't recognize the
56/// function id it cannot parse the call.
57template <typename FnIdT, typename SeqNoT>
58class BadFunctionCall
59 : public ErrorInfo<BadFunctionCall<FnIdT, SeqNoT>, RPCFatalError> {
60public:
61 static char ID;
62
63 BadFunctionCall(FnIdT FnId, SeqNoT SeqNo)
64 : FnId(std::move(FnId)), SeqNo(std::move(SeqNo)) {}
65
66 std::error_code convertToErrorCode() const override {
67 return orcError(OrcErrorCode::UnexpectedRPCCall);
68 }
69
70 void log(raw_ostream &OS) const override {
71 OS << "Call to invalid RPC function id '" << FnId << "' with "
72 "sequence number " << SeqNo;
73 }
74
75private:
76 FnIdT FnId;
77 SeqNoT SeqNo;
78};
79
80template <typename FnIdT, typename SeqNoT>
81char BadFunctionCall<FnIdT, SeqNoT>::ID = 0;
82
83/// InvalidSequenceNumberForResponse is returned from handleOne when a response
84/// call arrives with a sequence number that doesn't correspond to any in-flight
85/// function call.
86///
87/// This error is fatal because Orc RPC needs to know how to parse the rest of
88/// the response call to know where the next call starts, and if it doesn't have
89/// a result parser for this sequence number it can't do that.
90template <typename SeqNoT>
91class InvalidSequenceNumberForResponse
92 : public ErrorInfo<InvalidSequenceNumberForResponse<SeqNoT>, RPCFatalError> {
93public:
94 static char ID;
95
96 InvalidSequenceNumberForResponse(SeqNoT SeqNo)
97 : SeqNo(std::move(SeqNo)) {}
98
99 std::error_code convertToErrorCode() const override {
100 return orcError(OrcErrorCode::UnexpectedRPCCall);
101 };
102
103 void log(raw_ostream &OS) const override {
104 OS << "Response has unknown sequence number " << SeqNo;
105 }
106private:
107 SeqNoT SeqNo;
108};
109
110template <typename SeqNoT>
111char InvalidSequenceNumberForResponse<SeqNoT>::ID = 0;
112
113/// This non-fatal error will be passed to asynchronous result handlers in place
114/// of a result if the connection goes down before a result returns, or if the
115/// function to be called cannot be negotiated with the remote.
116class ResponseAbandoned : public ErrorInfo<ResponseAbandoned> {
117public:
118 static char ID;
119
120 std::error_code convertToErrorCode() const override;
121 void log(raw_ostream &OS) const override;
122};
123
124/// This error is returned if the remote does not have a handler installed for
125/// the given RPC function.
126class CouldNotNegotiate : public ErrorInfo<CouldNotNegotiate> {
127public:
128 static char ID;
129
130 CouldNotNegotiate(std::string Signature);
131 std::error_code convertToErrorCode() const override;
132 void log(raw_ostream &OS) const override;
133 const std::string &getSignature() const { return Signature; }
134private:
135 std::string Signature;
136};
137
138template <typename DerivedFunc, typename FnT> class Function;
139
140// RPC Function class.
141// DerivedFunc should be a user defined class with a static 'getName()' method
142// returning a const char* representing the function's name.
143template <typename DerivedFunc, typename RetT, typename... ArgTs>
144class Function<DerivedFunc, RetT(ArgTs...)> {
145public:
146 /// User defined function type.
147 using Type = RetT(ArgTs...);
148
149 /// Return type.
150 using ReturnType = RetT;
151
152 /// Returns the full function prototype as a string.
153 static const char *getPrototype() {
154 std::lock_guard<std::mutex> Lock(NameMutex);
155 if (Name.empty())
156 raw_string_ostream(Name)
157 << RPCTypeName<RetT>::getName() << " " << DerivedFunc::getName()
158 << "(" << llvm::orc::rpc::RPCTypeNameSequence<ArgTs...>() << ")";
159 return Name.data();
160 }
161
162private:
163 static std::mutex NameMutex;
164 static std::string Name;
165};
166
167template <typename DerivedFunc, typename RetT, typename... ArgTs>
168std::mutex Function<DerivedFunc, RetT(ArgTs...)>::NameMutex;
169
170template <typename DerivedFunc, typename RetT, typename... ArgTs>
171std::string Function<DerivedFunc, RetT(ArgTs...)>::Name;
172
173/// Allocates RPC function ids during autonegotiation.
174/// Specializations of this class must provide four members:
175///
176/// static T getInvalidId():
177/// Should return a reserved id that will be used to represent missing
178/// functions during autonegotiation.
179///
180/// static T getResponseId():
181/// Should return a reserved id that will be used to send function responses
182/// (return values).
183///
184/// static T getNegotiateId():
185/// Should return a reserved id for the negotiate function, which will be used
186/// to negotiate ids for user defined functions.
187///
188/// template <typename Func> T allocate():
189/// Allocate a unique id for function Func.
190template <typename T, typename = void> class RPCFunctionIdAllocator;
191
192/// This specialization of RPCFunctionIdAllocator provides a default
193/// implementation for integral types.
194template <typename T>
195class RPCFunctionIdAllocator<
196 T, typename std::enable_if<std::is_integral<T>::value>::type> {
197public:
198 static T getInvalidId() { return T(0); }
199 static T getResponseId() { return T(1); }
200 static T getNegotiateId() { return T(2); }
201
202 template <typename Func> T allocate() { return NextId++; }
203
204private:
205 T NextId = 3;
206};
207
208namespace detail {
209
210// FIXME: Remove MSVCPError/MSVCPExpected once MSVC's future implementation
211// supports classes without default constructors.
212#ifdef _MSC_VER
213
214namespace msvc_hacks {
215
216// Work around MSVC's future implementation's use of default constructors:
217// A default constructed value in the promise will be overwritten when the
218// real error is set - so the default constructed Error has to be checked
219// already.
220class MSVCPError : public Error {
221public:
222 MSVCPError() { (void)!!*this; }
223
224 MSVCPError(MSVCPError &&Other) : Error(std::move(Other)) {}
225
226 MSVCPError &operator=(MSVCPError Other) {
227 Error::operator=(std::move(Other));
228 return *this;
229 }
230
231 MSVCPError(Error Err) : Error(std::move(Err)) {}
232};
233
234// Work around MSVC's future implementation, similar to MSVCPError.
235template <typename T> class MSVCPExpected : public Expected<T> {
236public:
237 MSVCPExpected()
238 : Expected<T>(make_error<StringError>("", inconvertibleErrorCode())) {
239 consumeError(this->takeError());
240 }
241
242 MSVCPExpected(MSVCPExpected &&Other) : Expected<T>(std::move(Other)) {}
243
244 MSVCPExpected &operator=(MSVCPExpected &&Other) {
245 Expected<T>::operator=(std::move(Other));
246 return *this;
247 }
248
249 MSVCPExpected(Error Err) : Expected<T>(std::move(Err)) {}
250
251 template <typename OtherT>
252 MSVCPExpected(
253 OtherT &&Val,
254 typename std::enable_if<std::is_convertible<OtherT, T>::value>::type * =
255 nullptr)
256 : Expected<T>(std::move(Val)) {}
257
258 template <class OtherT>
259 MSVCPExpected(
260 Expected<OtherT> &&Other,
261 typename std::enable_if<std::is_convertible<OtherT, T>::value>::type * =
262 nullptr)
263 : Expected<T>(std::move(Other)) {}
264
265 template <class OtherT>
266 explicit MSVCPExpected(
267 Expected<OtherT> &&Other,
268 typename std::enable_if<!std::is_convertible<OtherT, T>::value>::type * =
269 nullptr)
270 : Expected<T>(std::move(Other)) {}
271};
272
273} // end namespace msvc_hacks
274
275#endif // _MSC_VER
276
277/// Provides a typedef for a tuple containing the decayed argument types.
278template <typename T> class FunctionArgsTuple;
279
280template <typename RetT, typename... ArgTs>
281class FunctionArgsTuple<RetT(ArgTs...)> {
282public:
283 using Type = std::tuple<typename std::decay<
284 typename std::remove_reference<ArgTs>::type>::type...>;
285};
286
287// ResultTraits provides typedefs and utilities specific to the return type
288// of functions.
289template <typename RetT> class ResultTraits {
290public:
291 // The return type wrapped in llvm::Expected.
292 using ErrorReturnType = Expected<RetT>;
293
294#ifdef _MSC_VER
295 // The ErrorReturnType wrapped in a std::promise.
296 using ReturnPromiseType = std::promise<msvc_hacks::MSVCPExpected<RetT>>;
297
298 // The ErrorReturnType wrapped in a std::future.
299 using ReturnFutureType = std::future<msvc_hacks::MSVCPExpected<RetT>>;
300#else
301 // The ErrorReturnType wrapped in a std::promise.
302 using ReturnPromiseType = std::promise<ErrorReturnType>;
303
304 // The ErrorReturnType wrapped in a std::future.
305 using ReturnFutureType = std::future<ErrorReturnType>;
306#endif
307
308 // Create a 'blank' value of the ErrorReturnType, ready and safe to
309 // overwrite.
310 static ErrorReturnType createBlankErrorReturnValue() {
311 return ErrorReturnType(RetT());
312 }
313
314 // Consume an abandoned ErrorReturnType.
315 static void consumeAbandoned(ErrorReturnType RetOrErr) {
316 consumeError(RetOrErr.takeError());
317 }
318};
319
320// ResultTraits specialization for void functions.
321template <> class ResultTraits<void> {
322public:
323 // For void functions, ErrorReturnType is llvm::Error.
324 using ErrorReturnType = Error;
325
326#ifdef _MSC_VER
327 // The ErrorReturnType wrapped in a std::promise.
328 using ReturnPromiseType = std::promise<msvc_hacks::MSVCPError>;
329
330 // The ErrorReturnType wrapped in a std::future.
331 using ReturnFutureType = std::future<msvc_hacks::MSVCPError>;
332#else
333 // The ErrorReturnType wrapped in a std::promise.
334 using ReturnPromiseType = std::promise<ErrorReturnType>;
335
336 // The ErrorReturnType wrapped in a std::future.
337 using ReturnFutureType = std::future<ErrorReturnType>;
338#endif
339
340 // Create a 'blank' value of the ErrorReturnType, ready and safe to
341 // overwrite.
342 static ErrorReturnType createBlankErrorReturnValue() {
343 return ErrorReturnType::success();
344 }
345
346 // Consume an abandoned ErrorReturnType.
347 static void consumeAbandoned(ErrorReturnType Err) {
348 consumeError(std::move(Err));
349 }
350};
351
352// ResultTraits<Error> is equivalent to ResultTraits<void>. This allows
353// handlers for void RPC functions to return either void (in which case they
354// implicitly succeed) or Error (in which case their error return is
355// propagated). See usage in HandlerTraits::runHandlerHelper.
356template <> class ResultTraits<Error> : public ResultTraits<void> {};
357
358// ResultTraits<Expected<T>> is equivalent to ResultTraits<T>. This allows
359// handlers for RPC functions returning a T to return either a T (in which
360// case they implicitly succeed) or Expected<T> (in which case their error
361// return is propagated). See usage in HandlerTraits::runHandlerHelper.
362template <typename RetT>
363class ResultTraits<Expected<RetT>> : public ResultTraits<RetT> {};
364
365// Determines whether an RPC function's defined error return type supports
366// error return value.
367template <typename T>
368class SupportsErrorReturn {
369public:
370 static const bool value = false;
371};
372
373template <>
374class SupportsErrorReturn<Error> {
375public:
376 static const bool value = true;
377};
378
379template <typename T>
380class SupportsErrorReturn<Expected<T>> {
381public:
382 static const bool value = true;
383};
384
385// RespondHelper packages return values based on whether or not the declared
386// RPC function return type supports error returns.
387template <bool FuncSupportsErrorReturn>
388class RespondHelper;
389
390// RespondHelper specialization for functions that support error returns.
391template <>
392class RespondHelper<true> {
393public:
394
395 // Send Expected<T>.
396 template <typename WireRetT, typename HandlerRetT, typename ChannelT,
397 typename FunctionIdT, typename SequenceNumberT>
398 static Error sendResult(ChannelT &C, const FunctionIdT &ResponseId,
399 SequenceNumberT SeqNo,
400 Expected<HandlerRetT> ResultOrErr) {
401 if (!ResultOrErr && ResultOrErr.template errorIsA<RPCFatalError>())
402 return ResultOrErr.takeError();
403
404 // Open the response message.
405 if (auto Err = C.startSendMessage(ResponseId, SeqNo))
406 return Err;
407
408 // Serialize the result.
409 if (auto Err =
410 SerializationTraits<ChannelT, WireRetT,
411 Expected<HandlerRetT>>::serialize(
412 C, std::move(ResultOrErr)))
413 return Err;
414
415 // Close the response message.
416 return C.endSendMessage();
417 }
418
419 template <typename ChannelT, typename FunctionIdT, typename SequenceNumberT>
420 static Error sendResult(ChannelT &C, const FunctionIdT &ResponseId,
421 SequenceNumberT SeqNo, Error Err) {
422 if (Err && Err.isA<RPCFatalError>())
423 return Err;
424 if (auto Err2 = C.startSendMessage(ResponseId, SeqNo))
425 return Err2;
426 if (auto Err2 = serializeSeq(C, std::move(Err)))
427 return Err2;
428 return C.endSendMessage();
429 }
430
431};
432
433// RespondHelper specialization for functions that do not support error returns.
434template <>
435class RespondHelper<false> {
436public:
437
438 template <typename WireRetT, typename HandlerRetT, typename ChannelT,
439 typename FunctionIdT, typename SequenceNumberT>
440 static Error sendResult(ChannelT &C, const FunctionIdT &ResponseId,
441 SequenceNumberT SeqNo,
442 Expected<HandlerRetT> ResultOrErr) {
443 if (auto Err = ResultOrErr.takeError())
444 return Err;
445
446 // Open the response message.
447 if (auto Err = C.startSendMessage(ResponseId, SeqNo))
448 return Err;
449
450 // Serialize the result.
451 if (auto Err =
452 SerializationTraits<ChannelT, WireRetT, HandlerRetT>::serialize(
453 C, *ResultOrErr))
454 return Err;
455
456 // Close the response message.
457 return C.endSendMessage();
458 }
459
460 template <typename ChannelT, typename FunctionIdT, typename SequenceNumberT>
461 static Error sendResult(ChannelT &C, const FunctionIdT &ResponseId,
462 SequenceNumberT SeqNo, Error Err) {
463 if (Err)
464 return Err;
465 if (auto Err2 = C.startSendMessage(ResponseId, SeqNo))
466 return Err2;
467 return C.endSendMessage();
468 }
469
470};
471
472
473// Send a response of the given wire return type (WireRetT) over the
474// channel, with the given sequence number.
475template <typename WireRetT, typename HandlerRetT, typename ChannelT,
476 typename FunctionIdT, typename SequenceNumberT>
477Error respond(ChannelT &C, const FunctionIdT &ResponseId,
478 SequenceNumberT SeqNo, Expected<HandlerRetT> ResultOrErr) {
479 return RespondHelper<SupportsErrorReturn<WireRetT>::value>::
480 template sendResult<WireRetT>(C, ResponseId, SeqNo, std::move(ResultOrErr));
481}
482
483// Send an empty response message on the given channel to indicate that
484// the handler ran.
485template <typename WireRetT, typename ChannelT, typename FunctionIdT,
486 typename SequenceNumberT>
487Error respond(ChannelT &C, const FunctionIdT &ResponseId, SequenceNumberT SeqNo,
488 Error Err) {
489 return RespondHelper<SupportsErrorReturn<WireRetT>::value>::
490 sendResult(C, ResponseId, SeqNo, std::move(Err));
491}
492
493// Converts a given type to the equivalent error return type.
494template <typename T> class WrappedHandlerReturn {
495public:
496 using Type = Expected<T>;
497};
498
499template <typename T> class WrappedHandlerReturn<Expected<T>> {
500public:
501 using Type = Expected<T>;
502};
503
504template <> class WrappedHandlerReturn<void> {
505public:
506 using Type = Error;
507};
508
509template <> class WrappedHandlerReturn<Error> {
510public:
511 using Type = Error;
512};
513
514template <> class WrappedHandlerReturn<ErrorSuccess> {
515public:
516 using Type = Error;
517};
518
519// Traits class that strips the response function from the list of handler
520// arguments.
521template <typename FnT> class AsyncHandlerTraits;
522
523template <typename ResultT, typename... ArgTs>
524class AsyncHandlerTraits<Error(std::function<Error(Expected<ResultT>)>, ArgTs...)> {
525public:
526 using Type = Error(ArgTs...);
527 using ResultType = Expected<ResultT>;
528};
529
530template <typename... ArgTs>
531class AsyncHandlerTraits<Error(std::function<Error(Error)>, ArgTs...)> {
532public:
533 using Type = Error(ArgTs...);
534 using ResultType = Error;
535};
536
537template <typename... ArgTs>
538class AsyncHandlerTraits<ErrorSuccess(std::function<Error(Error)>, ArgTs...)> {
539public:
540 using Type = Error(ArgTs...);
541 using ResultType = Error;
542};
543
544template <typename... ArgTs>
545class AsyncHandlerTraits<void(std::function<Error(Error)>, ArgTs...)> {
546public:
547 using Type = Error(ArgTs...);
548 using ResultType = Error;
549};
550
551template <typename ResponseHandlerT, typename... ArgTs>
552class AsyncHandlerTraits<Error(ResponseHandlerT, ArgTs...)> :
553 public AsyncHandlerTraits<Error(typename std::decay<ResponseHandlerT>::type,
554 ArgTs...)> {};
555
556// This template class provides utilities related to RPC function handlers.
557// The base case applies to non-function types (the template class is
558// specialized for function types) and inherits from the appropriate
559// speciilization for the given non-function type's call operator.
560template <typename HandlerT>
561class HandlerTraits : public HandlerTraits<decltype(
562 &std::remove_reference<HandlerT>::type::operator())> {
563};
564
565// Traits for handlers with a given function type.
566template <typename RetT, typename... ArgTs>
567class HandlerTraits<RetT(ArgTs...)> {
568public:
569 // Function type of the handler.
570 using Type = RetT(ArgTs...);
571
572 // Return type of the handler.
573 using ReturnType = RetT;
574
575 // Call the given handler with the given arguments.
576 template <typename HandlerT, typename... TArgTs>
577 static typename WrappedHandlerReturn<RetT>::Type
578 unpackAndRun(HandlerT &Handler, std::tuple<TArgTs...> &Args) {
579 return unpackAndRunHelper(Handler, Args,
580 llvm::index_sequence_for<TArgTs...>());
581 }
582
583 // Call the given handler with the given arguments.
584 template <typename HandlerT, typename ResponderT, typename... TArgTs>
585 static Error unpackAndRunAsync(HandlerT &Handler, ResponderT &Responder,
586 std::tuple<TArgTs...> &Args) {
587 return unpackAndRunAsyncHelper(Handler, Responder, Args,
588 llvm::index_sequence_for<TArgTs...>());
589 }
590
591 // Call the given handler with the given arguments.
592 template <typename HandlerT>
593 static typename std::enable_if<
594 std::is_void<typename HandlerTraits<HandlerT>::ReturnType>::value,
595 Error>::type
596 run(HandlerT &Handler, ArgTs &&... Args) {
597 Handler(std::move(Args)...);
598 return Error::success();
599 }
600
601 template <typename HandlerT, typename... TArgTs>
602 static typename std::enable_if<
603 !std::is_void<typename HandlerTraits<HandlerT>::ReturnType>::value,
604 typename HandlerTraits<HandlerT>::ReturnType>::type
605 run(HandlerT &Handler, TArgTs... Args) {
606 return Handler(std::move(Args)...);
607 }
608
609 // Serialize arguments to the channel.
610 template <typename ChannelT, typename... CArgTs>
611 static Error serializeArgs(ChannelT &C, const CArgTs... CArgs) {
612 return SequenceSerialization<ChannelT, ArgTs...>::serialize(C, CArgs...);
613 }
614
615 // Deserialize arguments from the channel.
616 template <typename ChannelT, typename... CArgTs>
617 static Error deserializeArgs(ChannelT &C, std::tuple<CArgTs...> &Args) {
618 return deserializeArgsHelper(C, Args,
619 llvm::index_sequence_for<CArgTs...>());
620 }
621
622private:
623 template <typename ChannelT, typename... CArgTs, size_t... Indexes>
624 static Error deserializeArgsHelper(ChannelT &C, std::tuple<CArgTs...> &Args,
625 llvm::index_sequence<Indexes...> _) {
626 return SequenceSerialization<ChannelT, ArgTs...>::deserialize(
627 C, std::get<Indexes>(Args)...);
628 }
629
630 template <typename HandlerT, typename ArgTuple, size_t... Indexes>
631 static typename WrappedHandlerReturn<
632 typename HandlerTraits<HandlerT>::ReturnType>::Type
633 unpackAndRunHelper(HandlerT &Handler, ArgTuple &Args,
634 llvm::index_sequence<Indexes...>) {
635 return run(Handler, std::move(std::get<Indexes>(Args))...);
636 }
637
638
639 template <typename HandlerT, typename ResponderT, typename ArgTuple,
640 size_t... Indexes>
641 static typename WrappedHandlerReturn<
642 typename HandlerTraits<HandlerT>::ReturnType>::Type
643 unpackAndRunAsyncHelper(HandlerT &Handler, ResponderT &Responder,
644 ArgTuple &Args,
645 llvm::index_sequence<Indexes...>) {
646 return run(Handler, Responder, std::move(std::get<Indexes>(Args))...);
647 }
648};
649
650// Handler traits for free functions.
651template <typename RetT, typename... ArgTs>
652class HandlerTraits<RetT(*)(ArgTs...)>
653 : public HandlerTraits<RetT(ArgTs...)> {};
654
655// Handler traits for class methods (especially call operators for lambdas).
656template <typename Class, typename RetT, typename... ArgTs>
657class HandlerTraits<RetT (Class::*)(ArgTs...)>
658 : public HandlerTraits<RetT(ArgTs...)> {};
659
660// Handler traits for const class methods (especially call operators for
661// lambdas).
662template <typename Class, typename RetT, typename... ArgTs>
663class HandlerTraits<RetT (Class::*)(ArgTs...) const>
664 : public HandlerTraits<RetT(ArgTs...)> {};
665
666// Utility to peel the Expected wrapper off a response handler error type.
667template <typename HandlerT> class ResponseHandlerArg;
668
669template <typename ArgT> class ResponseHandlerArg<Error(Expected<ArgT>)> {
670public:
671 using ArgType = Expected<ArgT>;
672 using UnwrappedArgType = ArgT;
673};
674
675template <typename ArgT>
676class ResponseHandlerArg<ErrorSuccess(Expected<ArgT>)> {
677public:
678 using ArgType = Expected<ArgT>;
679 using UnwrappedArgType = ArgT;
680};
681
682template <> class ResponseHandlerArg<Error(Error)> {
683public:
684 using ArgType = Error;
685};
686
687template <> class ResponseHandlerArg<ErrorSuccess(Error)> {
688public:
689 using ArgType = Error;
690};
691
692// ResponseHandler represents a handler for a not-yet-received function call
693// result.
694template <typename ChannelT> class ResponseHandler {
695public:
696 virtual ~ResponseHandler() {}
697
698 // Reads the function result off the wire and acts on it. The meaning of
699 // "act" will depend on how this method is implemented in any given
700 // ResponseHandler subclass but could, for example, mean running a
701 // user-specified handler or setting a promise value.
702 virtual Error handleResponse(ChannelT &C) = 0;
703
704 // Abandons this outstanding result.
705 virtual void abandon() = 0;
706
707 // Create an error instance representing an abandoned response.
708 static Error createAbandonedResponseError() {
709 return make_error<ResponseAbandoned>();
710 }
711};
712
713// ResponseHandler subclass for RPC functions with non-void returns.
714template <typename ChannelT, typename FuncRetT, typename HandlerT>
715class ResponseHandlerImpl : public ResponseHandler<ChannelT> {
716public:
717 ResponseHandlerImpl(HandlerT Handler) : Handler(std::move(Handler)) {}
718
719 // Handle the result by deserializing it from the channel then passing it
720 // to the user defined handler.
721 Error handleResponse(ChannelT &C) override {
722 using UnwrappedArgType = typename ResponseHandlerArg<
723 typename HandlerTraits<HandlerT>::Type>::UnwrappedArgType;
724 UnwrappedArgType Result;
725 if (auto Err =
726 SerializationTraits<ChannelT, FuncRetT,
727 UnwrappedArgType>::deserialize(C, Result))
728 return Err;
729 if (auto Err = C.endReceiveMessage())
730 return Err;
731 return Handler(std::move(Result));
732 }
733
734 // Abandon this response by calling the handler with an 'abandoned response'
735 // error.
736 void abandon() override {
737 if (auto Err = Handler(this->createAbandonedResponseError())) {
738 // Handlers should not fail when passed an abandoned response error.
739 report_fatal_error(std::move(Err));
740 }
741 }
742
743private:
744 HandlerT Handler;
745};
746
747// ResponseHandler subclass for RPC functions with void returns.
748template <typename ChannelT, typename HandlerT>
749class ResponseHandlerImpl<ChannelT, void, HandlerT>
750 : public ResponseHandler<ChannelT> {
751public:
752 ResponseHandlerImpl(HandlerT Handler) : Handler(std::move(Handler)) {}
753
754 // Handle the result (no actual value, just a notification that the function
755 // has completed on the remote end) by calling the user-defined handler with
756 // Error::success().
757 Error handleResponse(ChannelT &C) override {
758 if (auto Err = C.endReceiveMessage())
759 return Err;
760 return Handler(Error::success());
761 }
762
763 // Abandon this response by calling the handler with an 'abandoned response'
764 // error.
765 void abandon() override {
766 if (auto Err = Handler(this->createAbandonedResponseError())) {
767 // Handlers should not fail when passed an abandoned response error.
768 report_fatal_error(std::move(Err));
769 }
770 }
771
772private:
773 HandlerT Handler;
774};
775
776template <typename ChannelT, typename FuncRetT, typename HandlerT>
777class ResponseHandlerImpl<ChannelT, Expected<FuncRetT>, HandlerT>
778 : public ResponseHandler<ChannelT> {
779public:
780 ResponseHandlerImpl(HandlerT Handler) : Handler(std::move(Handler)) {}
781
782 // Handle the result by deserializing it from the channel then passing it
783 // to the user defined handler.
784 Error handleResponse(ChannelT &C) override {
785 using HandlerArgType = typename ResponseHandlerArg<
786 typename HandlerTraits<HandlerT>::Type>::ArgType;
787 HandlerArgType Result((typename HandlerArgType::value_type()));
788
789 if (auto Err =
790 SerializationTraits<ChannelT, Expected<FuncRetT>,
791 HandlerArgType>::deserialize(C, Result))
792 return Err;
793 if (auto Err = C.endReceiveMessage())
794 return Err;
795 return Handler(std::move(Result));
796 }
797
798 // Abandon this response by calling the handler with an 'abandoned response'
799 // error.
800 void abandon() override {
801 if (auto Err = Handler(this->createAbandonedResponseError())) {
802 // Handlers should not fail when passed an abandoned response error.
803 report_fatal_error(std::move(Err));
804 }
805 }
806
807private:
808 HandlerT Handler;
809};
810
811template <typename ChannelT, typename HandlerT>
812class ResponseHandlerImpl<ChannelT, Error, HandlerT>
813 : public ResponseHandler<ChannelT> {
814public:
815 ResponseHandlerImpl(HandlerT Handler) : Handler(std::move(Handler)) {}
816
817 // Handle the result by deserializing it from the channel then passing it
818 // to the user defined handler.
819 Error handleResponse(ChannelT &C) override {
820 Error Result = Error::success();
821 if (auto Err =
822 SerializationTraits<ChannelT, Error, Error>::deserialize(C, Result))
823 return Err;
824 if (auto Err = C.endReceiveMessage())
825 return Err;
826 return Handler(std::move(Result));
827 }
828
829 // Abandon this response by calling the handler with an 'abandoned response'
830 // error.
831 void abandon() override {
832 if (auto Err = Handler(this->createAbandonedResponseError())) {
833 // Handlers should not fail when passed an abandoned response error.
834 report_fatal_error(std::move(Err));
835 }
836 }
837
838private:
839 HandlerT Handler;
840};
841
842// Create a ResponseHandler from a given user handler.
843template <typename ChannelT, typename FuncRetT, typename HandlerT>
844std::unique_ptr<ResponseHandler<ChannelT>> createResponseHandler(HandlerT H) {
845 return llvm::make_unique<ResponseHandlerImpl<ChannelT, FuncRetT, HandlerT>>(
846 std::move(H));
847}
848
849// Helper for wrapping member functions up as functors. This is useful for
850// installing methods as result handlers.
851template <typename ClassT, typename RetT, typename... ArgTs>
852class MemberFnWrapper {
853public:
854 using MethodT = RetT (ClassT::*)(ArgTs...);
855 MemberFnWrapper(ClassT &Instance, MethodT Method)
856 : Instance(Instance), Method(Method) {}
857 RetT operator()(ArgTs &&... Args) {
858 return (Instance.*Method)(std::move(Args)...);
859 }
860
861private:
862 ClassT &Instance;
863 MethodT Method;
864};
865
866// Helper that provides a Functor for deserializing arguments.
867template <typename... ArgTs> class ReadArgs {
868public:
869 Error operator()() { return Error::success(); }
870};
871
872template <typename ArgT, typename... ArgTs>
873class ReadArgs<ArgT, ArgTs...> : public ReadArgs<ArgTs...> {
874public:
875 ReadArgs(ArgT &Arg, ArgTs &... Args)
876 : ReadArgs<ArgTs...>(Args...), Arg(Arg) {}
877
878 Error operator()(ArgT &ArgVal, ArgTs &... ArgVals) {
879 this->Arg = std::move(ArgVal);
880 return ReadArgs<ArgTs...>::operator()(ArgVals...);
881 }
882
883private:
884 ArgT &Arg;
885};
886
887// Manage sequence numbers.
888template <typename SequenceNumberT> class SequenceNumberManager {
889public:
890 // Reset, making all sequence numbers available.
891 void reset() {
892 std::lock_guard<std::mutex> Lock(SeqNoLock);
893 NextSequenceNumber = 0;
894 FreeSequenceNumbers.clear();
895 }
896
897 // Get the next available sequence number. Will re-use numbers that have
898 // been released.
899 SequenceNumberT getSequenceNumber() {
900 std::lock_guard<std::mutex> Lock(SeqNoLock);
901 if (FreeSequenceNumbers.empty())
902 return NextSequenceNumber++;
903 auto SequenceNumber = FreeSequenceNumbers.back();
904 FreeSequenceNumbers.pop_back();
905 return SequenceNumber;
906 }
907
908 // Release a sequence number, making it available for re-use.
909 void releaseSequenceNumber(SequenceNumberT SequenceNumber) {
910 std::lock_guard<std::mutex> Lock(SeqNoLock);
911 FreeSequenceNumbers.push_back(SequenceNumber);
912 }
913
914private:
915 std::mutex SeqNoLock;
916 SequenceNumberT NextSequenceNumber = 0;
917 std::vector<SequenceNumberT> FreeSequenceNumbers;
918};
919
920// Checks that predicate P holds for each corresponding pair of type arguments
921// from T1 and T2 tuple.
922template <template <class, class> class P, typename T1Tuple, typename T2Tuple>
923class RPCArgTypeCheckHelper;
924
925template <template <class, class> class P>
926class RPCArgTypeCheckHelper<P, std::tuple<>, std::tuple<>> {
927public:
928 static const bool value = true;
929};
930
931template <template <class, class> class P, typename T, typename... Ts,
932 typename U, typename... Us>
933class RPCArgTypeCheckHelper<P, std::tuple<T, Ts...>, std::tuple<U, Us...>> {
934public:
935 static const bool value =
936 P<T, U>::value &&
937 RPCArgTypeCheckHelper<P, std::tuple<Ts...>, std::tuple<Us...>>::value;
938};
939
940template <template <class, class> class P, typename T1Sig, typename T2Sig>
941class RPCArgTypeCheck {
942public:
943 using T1Tuple = typename FunctionArgsTuple<T1Sig>::Type;
944 using T2Tuple = typename FunctionArgsTuple<T2Sig>::Type;
945
946 static_assert(std::tuple_size<T1Tuple>::value >=
947 std::tuple_size<T2Tuple>::value,
948 "Too many arguments to RPC call");
949 static_assert(std::tuple_size<T1Tuple>::value <=
950 std::tuple_size<T2Tuple>::value,
951 "Too few arguments to RPC call");
952
953 static const bool value = RPCArgTypeCheckHelper<P, T1Tuple, T2Tuple>::value;
954};
955
956template <typename ChannelT, typename WireT, typename ConcreteT>
957class CanSerialize {
958private:
959 using S = SerializationTraits<ChannelT, WireT, ConcreteT>;
960
961 template <typename T>
962 static std::true_type
963 check(typename std::enable_if<
964 std::is_same<decltype(T::serialize(std::declval<ChannelT &>(),
965 std::declval<const ConcreteT &>())),
966 Error>::value,
967 void *>::type);
968
969 template <typename> static std::false_type check(...);
970
971public:
972 static const bool value = decltype(check<S>(0))::value;
973};
974
975template <typename ChannelT, typename WireT, typename ConcreteT>
976class CanDeserialize {
977private:
978 using S = SerializationTraits<ChannelT, WireT, ConcreteT>;
979
980 template <typename T>
981 static std::true_type
982 check(typename std::enable_if<
983 std::is_same<decltype(T::deserialize(std::declval<ChannelT &>(),
984 std::declval<ConcreteT &>())),
985 Error>::value,
986 void *>::type);
987
988 template <typename> static std::false_type check(...);
989
990public:
991 static const bool value = decltype(check<S>(0))::value;
992};
993
994/// Contains primitive utilities for defining, calling and handling calls to
995/// remote procedures. ChannelT is a bidirectional stream conforming to the
996/// RPCChannel interface (see RPCChannel.h), FunctionIdT is a procedure
997/// identifier type that must be serializable on ChannelT, and SequenceNumberT
998/// is an integral type that will be used to number in-flight function calls.
999///
1000/// These utilities support the construction of very primitive RPC utilities.
1001/// Their intent is to ensure correct serialization and deserialization of
1002/// procedure arguments, and to keep the client and server's view of the API in
1003/// sync.
1004template <typename ImplT, typename ChannelT, typename FunctionIdT,
1005 typename SequenceNumberT>
1006class RPCEndpointBase {
1007protected:
1008 class OrcRPCInvalid : public Function<OrcRPCInvalid, void()> {
1009 public:
1010 static const char *getName() { return "__orc_rpc$invalid"; }
1011 };
1012
1013 class OrcRPCResponse : public Function<OrcRPCResponse, void()> {
1014 public:
1015 static const char *getName() { return "__orc_rpc$response"; }
1016 };
1017
1018 class OrcRPCNegotiate
1019 : public Function<OrcRPCNegotiate, FunctionIdT(std::string)> {
1020 public:
1021 static const char *getName() { return "__orc_rpc$negotiate"; }
1022 };
1023
1024 // Helper predicate for testing for the presence of SerializeTraits
1025 // serializers.
1026 template <typename WireT, typename ConcreteT>
1027 class CanSerializeCheck : detail::CanSerialize<ChannelT, WireT, ConcreteT> {
1028 public:
1029 using detail::CanSerialize<ChannelT, WireT, ConcreteT>::value;
1030
1031 static_assert(value, "Missing serializer for argument (Can't serialize the "
1032 "first template type argument of CanSerializeCheck "
1033 "from the second)");
1034 };
1035
1036 // Helper predicate for testing for the presence of SerializeTraits
1037 // deserializers.
1038 template <typename WireT, typename ConcreteT>
1039 class CanDeserializeCheck
1040 : detail::CanDeserialize<ChannelT, WireT, ConcreteT> {
1041 public:
1042 using detail::CanDeserialize<ChannelT, WireT, ConcreteT>::value;
1043
1044 static_assert(value, "Missing deserializer for argument (Can't deserialize "
1045 "the second template type argument of "
1046 "CanDeserializeCheck from the first)");
1047 };
1048
1049public:
1050 /// Construct an RPC instance on a channel.
1051 RPCEndpointBase(ChannelT &C, bool LazyAutoNegotiation)
1052 : C(C), LazyAutoNegotiation(LazyAutoNegotiation) {
1053 // Hold ResponseId in a special variable, since we expect Response to be
1054 // called relatively frequently, and want to avoid the map lookup.
1055 ResponseId = FnIdAllocator.getResponseId();
1056 RemoteFunctionIds[OrcRPCResponse::getPrototype()] = ResponseId;
1057
1058 // Register the negotiate function id and handler.
1059 auto NegotiateId = FnIdAllocator.getNegotiateId();
1060 RemoteFunctionIds[OrcRPCNegotiate::getPrototype()] = NegotiateId;
1061 Handlers[NegotiateId] = wrapHandler<OrcRPCNegotiate>(
1062 [this](const std::string &Name) { return handleNegotiate(Name); });
1063 }
1064
1065
1066 /// Negotiate a function id for Func with the other end of the channel.
1067 template <typename Func> Error negotiateFunction(bool Retry = false) {
1068 return getRemoteFunctionId<Func>(true, Retry).takeError();
1069 }
1070
1071 /// Append a call Func, does not call send on the channel.
1072 /// The first argument specifies a user-defined handler to be run when the
1073 /// function returns. The handler should take an Expected<Func::ReturnType>,
1074 /// or an Error (if Func::ReturnType is void). The handler will be called
1075 /// with an error if the return value is abandoned due to a channel error.
1076 template <typename Func, typename HandlerT, typename... ArgTs>
1077 Error appendCallAsync(HandlerT Handler, const ArgTs &... Args) {
1078
1079 static_assert(
1080 detail::RPCArgTypeCheck<CanSerializeCheck, typename Func::Type,
1081 void(ArgTs...)>::value,
1082 "");
1083
1084 // Look up the function ID.
1085 FunctionIdT FnId;
1086 if (auto FnIdOrErr = getRemoteFunctionId<Func>(LazyAutoNegotiation, false))
1087 FnId = *FnIdOrErr;
1088 else {
1089 // Negotiation failed. Notify the handler then return the negotiate-failed
1090 // error.
1091 cantFail(Handler(make_error<ResponseAbandoned>()));
1092 return FnIdOrErr.takeError();
1093 }
1094
1095 SequenceNumberT SeqNo; // initialized in locked scope below.
1096 {
1097 // Lock the pending responses map and sequence number manager.
1098 std::lock_guard<std::mutex> Lock(ResponsesMutex);
1099
1100 // Allocate a sequence number.
1101 SeqNo = SequenceNumberMgr.getSequenceNumber();
1102 assert(!PendingResponses.count(SeqNo) &&(static_cast <bool> (!PendingResponses.count(SeqNo) &&
"Sequence number already allocated") ? void (0) : __assert_fail
("!PendingResponses.count(SeqNo) && \"Sequence number already allocated\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/ExecutionEngine/Orc/RPCUtils.h"
, 1103, __extension__ __PRETTY_FUNCTION__))
1103 "Sequence number already allocated")(static_cast <bool> (!PendingResponses.count(SeqNo) &&
"Sequence number already allocated") ? void (0) : __assert_fail
("!PendingResponses.count(SeqNo) && \"Sequence number already allocated\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/ExecutionEngine/Orc/RPCUtils.h"
, 1103, __extension__ __PRETTY_FUNCTION__))
;
1104
1105 // Install the user handler.
1106 PendingResponses[SeqNo] =
1107 detail::createResponseHandler<ChannelT, typename Func::ReturnType>(
1108 std::move(Handler));
1109 }
1110
1111 // Open the function call message.
1112 if (auto Err = C.startSendMessage(FnId, SeqNo)) {
1113 abandonPendingResponses();
1114 return Err;
1115 }
1116
1117 // Serialize the call arguments.
1118 if (auto Err = detail::HandlerTraits<typename Func::Type>::serializeArgs(
1119 C, Args...)) {
1120 abandonPendingResponses();
1121 return Err;
1122 }
1123
1124 // Close the function call messagee.
1125 if (auto Err = C.endSendMessage()) {
1126 abandonPendingResponses();
1127 return Err;
1128 }
1129
1130 return Error::success();
1131 }
1132
1133 Error sendAppendedCalls() { return C.send(); };
1134
1135 template <typename Func, typename HandlerT, typename... ArgTs>
1136 Error callAsync(HandlerT Handler, const ArgTs &... Args) {
1137 if (auto Err = appendCallAsync<Func>(std::move(Handler), Args...))
1138 return Err;
1139 return C.send();
1140 }
1141
1142 /// Handle one incoming call.
1143 Error handleOne() {
1144 FunctionIdT FnId;
1145 SequenceNumberT SeqNo;
1146 if (auto Err = C.startReceiveMessage(FnId, SeqNo)) {
7
Taking false branch
1147 abandonPendingResponses();
1148 return Err;
1149 }
1150 if (FnId == ResponseId)
8
Taking false branch
1151 return handleResponse(SeqNo);
1152 auto I = Handlers.find(FnId);
1153 if (I != Handlers.end())
9
Assuming the condition is false
10
Taking false branch
1154 return I->second(C, SeqNo);
1155
1156 // else: No handler found. Report error to client?
1157 return make_error<BadFunctionCall<FunctionIdT, SequenceNumberT>>(FnId,
11
Calling 'make_error'
1158 SeqNo);
1159 }
1160
1161 /// Helper for handling setter procedures - this method returns a functor that
1162 /// sets the variables referred to by Args... to values deserialized from the
1163 /// channel.
1164 /// E.g.
1165 ///
1166 /// typedef Function<0, bool, int> Func1;
1167 ///
1168 /// ...
1169 /// bool B;
1170 /// int I;
1171 /// if (auto Err = expect<Func1>(Channel, readArgs(B, I)))
1172 /// /* Handle Args */ ;
1173 ///
1174 template <typename... ArgTs>
1175 static detail::ReadArgs<ArgTs...> readArgs(ArgTs &... Args) {
1176 return detail::ReadArgs<ArgTs...>(Args...);
1177 }
1178
1179 /// Abandon all outstanding result handlers.
1180 ///
1181 /// This will call all currently registered result handlers to receive an
1182 /// "abandoned" error as their argument. This is used internally by the RPC
1183 /// in error situations, but can also be called directly by clients who are
1184 /// disconnecting from the remote and don't or can't expect responses to their
1185 /// outstanding calls. (Especially for outstanding blocking calls, calling
1186 /// this function may be necessary to avoid dead threads).
1187 void abandonPendingResponses() {
1188 // Lock the pending responses map and sequence number manager.
1189 std::lock_guard<std::mutex> Lock(ResponsesMutex);
1190
1191 for (auto &KV : PendingResponses)
1192 KV.second->abandon();
1193 PendingResponses.clear();
1194 SequenceNumberMgr.reset();
1195 }
1196
1197 /// Remove the handler for the given function.
1198 /// A handler must currently be registered for this function.
1199 template <typename Func>
1200 void removeHandler() {
1201 auto IdItr = LocalFunctionIds.find(Func::getPrototype());
1202 assert(IdItr != LocalFunctionIds.end() &&(static_cast <bool> (IdItr != LocalFunctionIds.end() &&
"Function does not have a registered handler") ? void (0) : __assert_fail
("IdItr != LocalFunctionIds.end() && \"Function does not have a registered handler\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/ExecutionEngine/Orc/RPCUtils.h"
, 1203, __extension__ __PRETTY_FUNCTION__))
1203 "Function does not have a registered handler")(static_cast <bool> (IdItr != LocalFunctionIds.end() &&
"Function does not have a registered handler") ? void (0) : __assert_fail
("IdItr != LocalFunctionIds.end() && \"Function does not have a registered handler\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/ExecutionEngine/Orc/RPCUtils.h"
, 1203, __extension__ __PRETTY_FUNCTION__))
;
1204 auto HandlerItr = Handlers.find(IdItr->second);
1205 assert(HandlerItr != Handlers.end() &&(static_cast <bool> (HandlerItr != Handlers.end() &&
"Function does not have a registered handler") ? void (0) : __assert_fail
("HandlerItr != Handlers.end() && \"Function does not have a registered handler\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/ExecutionEngine/Orc/RPCUtils.h"
, 1206, __extension__ __PRETTY_FUNCTION__))
1206 "Function does not have a registered handler")(static_cast <bool> (HandlerItr != Handlers.end() &&
"Function does not have a registered handler") ? void (0) : __assert_fail
("HandlerItr != Handlers.end() && \"Function does not have a registered handler\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/ExecutionEngine/Orc/RPCUtils.h"
, 1206, __extension__ __PRETTY_FUNCTION__))
;
1207 Handlers.erase(HandlerItr);
1208 }
1209
1210 /// Clear all handlers.
1211 void clearHandlers() {
1212 Handlers.clear();
1213 }
1214
1215protected:
1216
1217 FunctionIdT getInvalidFunctionId() const {
1218 return FnIdAllocator.getInvalidId();
1219 }
1220
1221 /// Add the given handler to the handler map and make it available for
1222 /// autonegotiation and execution.
1223 template <typename Func, typename HandlerT>
1224 void addHandlerImpl(HandlerT Handler) {
1225
1226 static_assert(detail::RPCArgTypeCheck<
1227 CanDeserializeCheck, typename Func::Type,
1228 typename detail::HandlerTraits<HandlerT>::Type>::value,
1229 "");
1230
1231 FunctionIdT NewFnId = FnIdAllocator.template allocate<Func>();
1232 LocalFunctionIds[Func::getPrototype()] = NewFnId;
1233 Handlers[NewFnId] = wrapHandler<Func>(std::move(Handler));
1234 }
1235
1236 template <typename Func, typename HandlerT>
1237 void addAsyncHandlerImpl(HandlerT Handler) {
1238
1239 static_assert(detail::RPCArgTypeCheck<
1240 CanDeserializeCheck, typename Func::Type,
1241 typename detail::AsyncHandlerTraits<
1242 typename detail::HandlerTraits<HandlerT>::Type
1243 >::Type>::value,
1244 "");
1245
1246 FunctionIdT NewFnId = FnIdAllocator.template allocate<Func>();
1247 LocalFunctionIds[Func::getPrototype()] = NewFnId;
1248 Handlers[NewFnId] = wrapAsyncHandler<Func>(std::move(Handler));
1249 }
1250
1251 Error handleResponse(SequenceNumberT SeqNo) {
1252 using Handler = typename decltype(PendingResponses)::mapped_type;
1253 Handler PRHandler;
1254
1255 {
1256 // Lock the pending responses map and sequence number manager.
1257 std::unique_lock<std::mutex> Lock(ResponsesMutex);
1258 auto I = PendingResponses.find(SeqNo);
1259
1260 if (I != PendingResponses.end()) {
1261 PRHandler = std::move(I->second);
1262 PendingResponses.erase(I);
1263 SequenceNumberMgr.releaseSequenceNumber(SeqNo);
1264 } else {
1265 // Unlock the pending results map to prevent recursive lock.
1266 Lock.unlock();
1267 abandonPendingResponses();
1268 return make_error<
1269 InvalidSequenceNumberForResponse<SequenceNumberT>>(SeqNo);
1270 }
1271 }
1272
1273 assert(PRHandler &&(static_cast <bool> (PRHandler && "If we didn't find a response handler we should have bailed out"
) ? void (0) : __assert_fail ("PRHandler && \"If we didn't find a response handler we should have bailed out\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/ExecutionEngine/Orc/RPCUtils.h"
, 1274, __extension__ __PRETTY_FUNCTION__))
1274 "If we didn't find a response handler we should have bailed out")(static_cast <bool> (PRHandler && "If we didn't find a response handler we should have bailed out"
) ? void (0) : __assert_fail ("PRHandler && \"If we didn't find a response handler we should have bailed out\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/ExecutionEngine/Orc/RPCUtils.h"
, 1274, __extension__ __PRETTY_FUNCTION__))
;
1275
1276 if (auto Err = PRHandler->handleResponse(C)) {
1277 abandonPendingResponses();
1278 return Err;
1279 }
1280
1281 return Error::success();
1282 }
1283
1284 FunctionIdT handleNegotiate(const std::string &Name) {
1285 auto I = LocalFunctionIds.find(Name);
1286 if (I == LocalFunctionIds.end())
1287 return getInvalidFunctionId();
1288 return I->second;
1289 }
1290
1291 // Find the remote FunctionId for the given function.
1292 template <typename Func>
1293 Expected<FunctionIdT> getRemoteFunctionId(bool NegotiateIfNotInMap,
1294 bool NegotiateIfInvalid) {
1295 bool DoNegotiate;
1296
1297 // Check if we already have a function id...
1298 auto I = RemoteFunctionIds.find(Func::getPrototype());
1299 if (I != RemoteFunctionIds.end()) {
1300 // If it's valid there's nothing left to do.
1301 if (I->second != getInvalidFunctionId())
1302 return I->second;
1303 DoNegotiate = NegotiateIfInvalid;
1304 } else
1305 DoNegotiate = NegotiateIfNotInMap;
1306
1307 // We don't have a function id for Func yet, but we're allowed to try to
1308 // negotiate one.
1309 if (DoNegotiate) {
1310 auto &Impl = static_cast<ImplT &>(*this);
1311 if (auto RemoteIdOrErr =
1312 Impl.template callB<OrcRPCNegotiate>(Func::getPrototype())) {
1313 RemoteFunctionIds[Func::getPrototype()] = *RemoteIdOrErr;
1314 if (*RemoteIdOrErr == getInvalidFunctionId())
1315 return make_error<CouldNotNegotiate>(Func::getPrototype());
1316 return *RemoteIdOrErr;
1317 } else
1318 return RemoteIdOrErr.takeError();
1319 }
1320
1321 // No key was available in the map and we weren't allowed to try to
1322 // negotiate one, so return an unknown function error.
1323 return make_error<CouldNotNegotiate>(Func::getPrototype());
1324 }
1325
1326 using WrappedHandlerFn = std::function<Error(ChannelT &, SequenceNumberT)>;
1327
1328 // Wrap the given user handler in the necessary argument-deserialization code,
1329 // result-serialization code, and call to the launch policy (if present).
1330 template <typename Func, typename HandlerT>
1331 WrappedHandlerFn wrapHandler(HandlerT Handler) {
1332 return [this, Handler](ChannelT &Channel,
1333 SequenceNumberT SeqNo) mutable -> Error {
1334 // Start by deserializing the arguments.
1335 using ArgsTuple =
1336 typename detail::FunctionArgsTuple<
1337 typename detail::HandlerTraits<HandlerT>::Type>::Type;
1338 auto Args = std::make_shared<ArgsTuple>();
1339
1340 if (auto Err =
1341 detail::HandlerTraits<typename Func::Type>::deserializeArgs(
1342 Channel, *Args))
1343 return Err;
1344
1345 // GCC 4.7 and 4.8 incorrectly issue a -Wunused-but-set-variable warning
1346 // for RPCArgs. Void cast RPCArgs to work around this for now.
1347 // FIXME: Remove this workaround once we can assume a working GCC version.
1348 (void)Args;
1349
1350 // End receieve message, unlocking the channel for reading.
1351 if (auto Err = Channel.endReceiveMessage())
1352 return Err;
1353
1354 using HTraits = detail::HandlerTraits<HandlerT>;
1355 using FuncReturn = typename Func::ReturnType;
1356 return detail::respond<FuncReturn>(Channel, ResponseId, SeqNo,
1357 HTraits::unpackAndRun(Handler, *Args));
1358 };
1359 }
1360
1361 // Wrap the given user handler in the necessary argument-deserialization code,
1362 // result-serialization code, and call to the launch policy (if present).
1363 template <typename Func, typename HandlerT>
1364 WrappedHandlerFn wrapAsyncHandler(HandlerT Handler) {
1365 return [this, Handler](ChannelT &Channel,
1366 SequenceNumberT SeqNo) mutable -> Error {
1367 // Start by deserializing the arguments.
1368 using AHTraits = detail::AsyncHandlerTraits<
1369 typename detail::HandlerTraits<HandlerT>::Type>;
1370 using ArgsTuple =
1371 typename detail::FunctionArgsTuple<typename AHTraits::Type>::Type;
1372 auto Args = std::make_shared<ArgsTuple>();
1373
1374 if (auto Err =
1375 detail::HandlerTraits<typename Func::Type>::deserializeArgs(
1376 Channel, *Args))
1377 return Err;
1378
1379 // GCC 4.7 and 4.8 incorrectly issue a -Wunused-but-set-variable warning
1380 // for RPCArgs. Void cast RPCArgs to work around this for now.
1381 // FIXME: Remove this workaround once we can assume a working GCC version.
1382 (void)Args;
1383
1384 // End receieve message, unlocking the channel for reading.
1385 if (auto Err = Channel.endReceiveMessage())
1386 return Err;
1387
1388 using HTraits = detail::HandlerTraits<HandlerT>;
1389 using FuncReturn = typename Func::ReturnType;
1390 auto Responder =
1391 [this, SeqNo](typename AHTraits::ResultType RetVal) -> Error {
1392 return detail::respond<FuncReturn>(C, ResponseId, SeqNo,
1393 std::move(RetVal));
1394 };
1395
1396 return HTraits::unpackAndRunAsync(Handler, Responder, *Args);
1397 };
1398 }
1399
1400 ChannelT &C;
1401
1402 bool LazyAutoNegotiation;
1403
1404 RPCFunctionIdAllocator<FunctionIdT> FnIdAllocator;
1405
1406 FunctionIdT ResponseId;
1407 std::map<std::string, FunctionIdT> LocalFunctionIds;
1408 std::map<const char *, FunctionIdT> RemoteFunctionIds;
1409
1410 std::map<FunctionIdT, WrappedHandlerFn> Handlers;
1411
1412 std::mutex ResponsesMutex;
1413 detail::SequenceNumberManager<SequenceNumberT> SequenceNumberMgr;
1414 std::map<SequenceNumberT, std::unique_ptr<detail::ResponseHandler<ChannelT>>>
1415 PendingResponses;
1416};
1417
1418} // end namespace detail
1419
1420template <typename ChannelT, typename FunctionIdT = uint32_t,
1421 typename SequenceNumberT = uint32_t>
1422class MultiThreadedRPCEndpoint
1423 : public detail::RPCEndpointBase<
1424 MultiThreadedRPCEndpoint<ChannelT, FunctionIdT, SequenceNumberT>,
1425 ChannelT, FunctionIdT, SequenceNumberT> {
1426private:
1427 using BaseClass =
1428 detail::RPCEndpointBase<
1429 MultiThreadedRPCEndpoint<ChannelT, FunctionIdT, SequenceNumberT>,
1430 ChannelT, FunctionIdT, SequenceNumberT>;
1431
1432public:
1433 MultiThreadedRPCEndpoint(ChannelT &C, bool LazyAutoNegotiation)
1434 : BaseClass(C, LazyAutoNegotiation) {}
1435
1436 /// Add a handler for the given RPC function.
1437 /// This installs the given handler functor for the given RPC Function, and
1438 /// makes the RPC function available for negotiation/calling from the remote.
1439 template <typename Func, typename HandlerT>
1440 void addHandler(HandlerT Handler) {
1441 return this->template addHandlerImpl<Func>(std::move(Handler));
1442 }
1443
1444 /// Add a class-method as a handler.
1445 template <typename Func, typename ClassT, typename RetT, typename... ArgTs>
1446 void addHandler(ClassT &Object, RetT (ClassT::*Method)(ArgTs...)) {
1447 addHandler<Func>(
1448 detail::MemberFnWrapper<ClassT, RetT, ArgTs...>(Object, Method));
1449 }
1450
1451 template <typename Func, typename HandlerT>
1452 void addAsyncHandler(HandlerT Handler) {
1453 return this->template addAsyncHandlerImpl<Func>(std::move(Handler));
1454 }
1455
1456 /// Add a class-method as a handler.
1457 template <typename Func, typename ClassT, typename RetT, typename... ArgTs>
1458 void addAsyncHandler(ClassT &Object, RetT (ClassT::*Method)(ArgTs...)) {
1459 addAsyncHandler<Func>(
1460 detail::MemberFnWrapper<ClassT, RetT, ArgTs...>(Object, Method));
1461 }
1462
1463 /// Return type for non-blocking call primitives.
1464 template <typename Func>
1465 using NonBlockingCallResult = typename detail::ResultTraits<
1466 typename Func::ReturnType>::ReturnFutureType;
1467
1468 /// Call Func on Channel C. Does not block, does not call send. Returns a pair
1469 /// of a future result and the sequence number assigned to the result.
1470 ///
1471 /// This utility function is primarily used for single-threaded mode support,
1472 /// where the sequence number can be used to wait for the corresponding
1473 /// result. In multi-threaded mode the appendCallNB method, which does not
1474 /// return the sequence numeber, should be preferred.
1475 template <typename Func, typename... ArgTs>
1476 Expected<NonBlockingCallResult<Func>> appendCallNB(const ArgTs &... Args) {
1477 using RTraits = detail::ResultTraits<typename Func::ReturnType>;
1478 using ErrorReturn = typename RTraits::ErrorReturnType;
1479 using ErrorReturnPromise = typename RTraits::ReturnPromiseType;
1480
1481 // FIXME: Stack allocate and move this into the handler once LLVM builds
1482 // with C++14.
1483 auto Promise = std::make_shared<ErrorReturnPromise>();
1484 auto FutureResult = Promise->get_future();
1485
1486 if (auto Err = this->template appendCallAsync<Func>(
1487 [Promise](ErrorReturn RetOrErr) {
1488 Promise->set_value(std::move(RetOrErr));
1489 return Error::success();
1490 },
1491 Args...)) {
1492 RTraits::consumeAbandoned(FutureResult.get());
1493 return std::move(Err);
1494 }
1495 return std::move(FutureResult);
1496 }
1497
1498 /// The same as appendCallNBWithSeq, except that it calls C.send() to
1499 /// flush the channel after serializing the call.
1500 template <typename Func, typename... ArgTs>
1501 Expected<NonBlockingCallResult<Func>> callNB(const ArgTs &... Args) {
1502 auto Result = appendCallNB<Func>(Args...);
1503 if (!Result)
1504 return Result;
1505 if (auto Err = this->C.send()) {
1506 this->abandonPendingResponses();
1507 detail::ResultTraits<typename Func::ReturnType>::consumeAbandoned(
1508 std::move(Result->get()));
1509 return std::move(Err);
1510 }
1511 return Result;
1512 }
1513
1514 /// Call Func on Channel C. Blocks waiting for a result. Returns an Error
1515 /// for void functions or an Expected<T> for functions returning a T.
1516 ///
1517 /// This function is for use in threaded code where another thread is
1518 /// handling responses and incoming calls.
1519 template <typename Func, typename... ArgTs,
1520 typename AltRetT = typename Func::ReturnType>
1521 typename detail::ResultTraits<AltRetT>::ErrorReturnType
1522 callB(const ArgTs &... Args) {
1523 if (auto FutureResOrErr = callNB<Func>(Args...))
1524 return FutureResOrErr->get();
1525 else
1526 return FutureResOrErr.takeError();
1527 }
1528
1529 /// Handle incoming RPC calls.
1530 Error handlerLoop() {
1531 while (true)
1532 if (auto Err = this->handleOne())
1533 return Err;
1534 return Error::success();
1535 }
1536};
1537
1538template <typename ChannelT, typename FunctionIdT = uint32_t,
1539 typename SequenceNumberT = uint32_t>
1540class SingleThreadedRPCEndpoint
1541 : public detail::RPCEndpointBase<
1542 SingleThreadedRPCEndpoint<ChannelT, FunctionIdT, SequenceNumberT>,
1543 ChannelT, FunctionIdT, SequenceNumberT> {
1544private:
1545 using BaseClass =
1546 detail::RPCEndpointBase<
1547 SingleThreadedRPCEndpoint<ChannelT, FunctionIdT, SequenceNumberT>,
1548 ChannelT, FunctionIdT, SequenceNumberT>;
1549
1550public:
1551 SingleThreadedRPCEndpoint(ChannelT &C, bool LazyAutoNegotiation)
1552 : BaseClass(C, LazyAutoNegotiation) {}
1553
1554 template <typename Func, typename HandlerT>
1555 void addHandler(HandlerT Handler) {
1556 return this->template addHandlerImpl<Func>(std::move(Handler));
1557 }
1558
1559 template <typename Func, typename ClassT, typename RetT, typename... ArgTs>
1560 void addHandler(ClassT &Object, RetT (ClassT::*Method)(ArgTs...)) {
1561 addHandler<Func>(
1562 detail::MemberFnWrapper<ClassT, RetT, ArgTs...>(Object, Method));
1563 }
1564
1565 template <typename Func, typename HandlerT>
1566 void addAsyncHandler(HandlerT Handler) {
1567 return this->template addAsyncHandlerImpl<Func>(std::move(Handler));
1568 }
1569
1570 /// Add a class-method as a handler.
1571 template <typename Func, typename ClassT, typename RetT, typename... ArgTs>
1572 void addAsyncHandler(ClassT &Object, RetT (ClassT::*Method)(ArgTs...)) {
1573 addAsyncHandler<Func>(
1574 detail::MemberFnWrapper<ClassT, RetT, ArgTs...>(Object, Method));
1575 }
1576
1577 template <typename Func, typename... ArgTs,
1578 typename AltRetT = typename Func::ReturnType>
1579 typename detail::ResultTraits<AltRetT>::ErrorReturnType
1580 callB(const ArgTs &... Args) {
1581 bool ReceivedResponse = false;
1582 using ResultType = typename detail::ResultTraits<AltRetT>::ErrorReturnType;
1583 auto Result = detail::ResultTraits<AltRetT>::createBlankErrorReturnValue();
1584
1585 // We have to 'Check' result (which we know is in a success state at this
1586 // point) so that it can be overwritten in the async handler.
1587 (void)!!Result;
1588
1589 if (auto Err = this->template appendCallAsync<Func>(
1590 [&](ResultType R) {
1591 Result = std::move(R);
1592 ReceivedResponse = true;
1593 return Error::success();
1594 },
1595 Args...)) {
1596 detail::ResultTraits<typename Func::ReturnType>::consumeAbandoned(
1597 std::move(Result));
1598 return std::move(Err);
1599 }
1600
1601 while (!ReceivedResponse) {
1602 if (auto Err = this->handleOne()) {
1603 detail::ResultTraits<typename Func::ReturnType>::consumeAbandoned(
1604 std::move(Result));
1605 return std::move(Err);
1606 }
1607 }
1608
1609 return Result;
1610 }
1611};
1612
1613/// Asynchronous dispatch for a function on an RPC endpoint.
1614template <typename RPCClass, typename Func>
1615class RPCAsyncDispatch {
1616public:
1617 RPCAsyncDispatch(RPCClass &Endpoint) : Endpoint(Endpoint) {}
1618
1619 template <typename HandlerT, typename... ArgTs>
1620 Error operator()(HandlerT Handler, const ArgTs &... Args) const {
1621 return Endpoint.template appendCallAsync<Func>(std::move(Handler), Args...);
1622 }
1623
1624private:
1625 RPCClass &Endpoint;
1626};
1627
1628/// Construct an asynchronous dispatcher from an RPC endpoint and a Func.
1629template <typename Func, typename RPCEndpointT>
1630RPCAsyncDispatch<RPCEndpointT, Func> rpcAsyncDispatch(RPCEndpointT &Endpoint) {
1631 return RPCAsyncDispatch<RPCEndpointT, Func>(Endpoint);
1632}
1633
1634/// \brief Allows a set of asynchrounous calls to be dispatched, and then
1635/// waited on as a group.
1636class ParallelCallGroup {
1637public:
1638
1639 ParallelCallGroup() = default;
1640 ParallelCallGroup(const ParallelCallGroup &) = delete;
1641 ParallelCallGroup &operator=(const ParallelCallGroup &) = delete;
1642
1643 /// \brief Make as asynchronous call.
1644 template <typename AsyncDispatcher, typename HandlerT, typename... ArgTs>
1645 Error call(const AsyncDispatcher &AsyncDispatch, HandlerT Handler,
1646 const ArgTs &... Args) {
1647 // Increment the count of outstanding calls. This has to happen before
1648 // we invoke the call, as the handler may (depending on scheduling)
1649 // be run immediately on another thread, and we don't want the decrement
1650 // in the wrapped handler below to run before the increment.
1651 {
1652 std::unique_lock<std::mutex> Lock(M);
1653 ++NumOutstandingCalls;
1654 }
1655
1656 // Wrap the user handler in a lambda that will decrement the
1657 // outstanding calls count, then poke the condition variable.
1658 using ArgType = typename detail::ResponseHandlerArg<
1659 typename detail::HandlerTraits<HandlerT>::Type>::ArgType;
1660 // FIXME: Move handler into wrapped handler once we have C++14.
1661 auto WrappedHandler = [this, Handler](ArgType Arg) {
1662 auto Err = Handler(std::move(Arg));
1663 std::unique_lock<std::mutex> Lock(M);
1664 --NumOutstandingCalls;
1665 CV.notify_all();
1666 return Err;
1667 };
1668
1669 return AsyncDispatch(std::move(WrappedHandler), Args...);
1670 }
1671
1672 /// \brief Blocks until all calls have been completed and their return value
1673 /// handlers run.
1674 void wait() {
1675 std::unique_lock<std::mutex> Lock(M);
1676 while (NumOutstandingCalls > 0)
1677 CV.wait(Lock);
1678 }
1679
1680private:
1681 std::mutex M;
1682 std::condition_variable CV;
1683 uint32_t NumOutstandingCalls = 0;
1684};
1685
1686/// @brief Convenience class for grouping RPC Functions into APIs that can be
1687/// negotiated as a block.
1688///
1689template <typename... Funcs>
1690class APICalls {
1691public:
1692
1693 /// @brief Test whether this API contains Function F.
1694 template <typename F>
1695 class Contains {
1696 public:
1697 static const bool value = false;
1698 };
1699
1700 /// @brief Negotiate all functions in this API.
1701 template <typename RPCEndpoint>
1702 static Error negotiate(RPCEndpoint &R) {
1703 return Error::success();
1704 }
1705};
1706
1707template <typename Func, typename... Funcs>
1708class APICalls<Func, Funcs...> {
1709public:
1710
1711 template <typename F>
1712 class Contains {
1713 public:
1714 static const bool value = std::is_same<F, Func>::value |
1715 APICalls<Funcs...>::template Contains<F>::value;
1716 };
1717
1718 template <typename RPCEndpoint>
1719 static Error negotiate(RPCEndpoint &R) {
1720 if (auto Err = R.template negotiateFunction<Func>())
1721 return Err;
1722 return APICalls<Funcs...>::negotiate(R);
1723 }
1724
1725};
1726
1727template <typename... InnerFuncs, typename... Funcs>
1728class APICalls<APICalls<InnerFuncs...>, Funcs...> {
1729public:
1730
1731 template <typename F>
1732 class Contains {
1733 public:
1734 static const bool value =
1735 APICalls<InnerFuncs...>::template Contains<F>::value |
1736 APICalls<Funcs...>::template Contains<F>::value;
1737 };
1738
1739 template <typename RPCEndpoint>
1740 static Error negotiate(RPCEndpoint &R) {
1741 if (auto Err = APICalls<InnerFuncs...>::negotiate(R))
1742 return Err;
1743 return APICalls<Funcs...>::negotiate(R);
1744 }
1745
1746};
1747
1748} // end namespace rpc
1749} // end namespace orc
1750} // end namespace llvm
1751
1752#endif

/build/llvm-toolchain-snapshot-6.0~svn318693/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/ADT/SmallVector.h"
18#include "llvm/ADT/STLExtras.h"
19#include "llvm/ADT/StringExtras.h"
20#include "llvm/ADT/Twine.h"
21#include "llvm/Config/abi-breaking.h"
22#include "llvm/Support/AlignOf.h"
23#include "llvm/Support/Compiler.h"
24#include "llvm/Support/Debug.h"
25#include "llvm/Support/ErrorHandling.h"
26#include "llvm/Support/ErrorOr.h"
27#include "llvm/Support/raw_ostream.h"
28#include <algorithm>
29#include <cassert>
30#include <cstdint>
31#include <cstdlib>
32#include <functional>
33#include <memory>
34#include <new>
35#include <string>
36#include <system_error>
37#include <type_traits>
38#include <utility>
39#include <vector>
40
41namespace llvm {
42
43class ErrorSuccess;
44
45/// Base class for error info classes. Do not extend this directly: Extend
46/// the ErrorInfo template subclass instead.
47class ErrorInfoBase {
48public:
49 virtual ~ErrorInfoBase() = default;
50
51 /// Print an error message to an output stream.
52 virtual void log(raw_ostream &OS) const = 0;
53
54 /// Return the error message as a string.
55 virtual std::string message() const {
56 std::string Msg;
57 raw_string_ostream OS(Msg);
58 log(OS);
59 return OS.str();
60 }
61
62 /// Convert this error to a std::error_code.
63 ///
64 /// This is a temporary crutch to enable interaction with code still
65 /// using std::error_code. It will be removed in the future.
66 virtual std::error_code convertToErrorCode() const = 0;
67
68 // Returns the class ID for this type.
69 static const void *classID() { return &ID; }
70
71 // Returns the class ID for the dynamic type of this ErrorInfoBase instance.
72 virtual const void *dynamicClassID() const = 0;
73
74 // Check whether this instance is a subclass of the class identified by
75 // ClassID.
76 virtual bool isA(const void *const ClassID) const {
77 return ClassID == classID();
78 }
79
80 // Check whether this instance is a subclass of ErrorInfoT.
81 template <typename ErrorInfoT> bool isA() const {
82 return isA(ErrorInfoT::classID());
83 }
84
85private:
86 virtual void anchor();
87
88 static char ID;
89};
90
91/// Lightweight error class with error context and mandatory checking.
92///
93/// Instances of this class wrap a ErrorInfoBase pointer. Failure states
94/// are represented by setting the pointer to a ErrorInfoBase subclass
95/// instance containing information describing the failure. Success is
96/// represented by a null pointer value.
97///
98/// Instances of Error also contains a 'Checked' flag, which must be set
99/// before the destructor is called, otherwise the destructor will trigger a
100/// runtime error. This enforces at runtime the requirement that all Error
101/// instances be checked or returned to the caller.
102///
103/// There are two ways to set the checked flag, depending on what state the
104/// Error instance is in. For Error instances indicating success, it
105/// is sufficient to invoke the boolean conversion operator. E.g.:
106///
107/// @code{.cpp}
108/// Error foo(<...>);
109///
110/// if (auto E = foo(<...>))
111/// return E; // <- Return E if it is in the error state.
112/// // We have verified that E was in the success state. It can now be safely
113/// // destroyed.
114/// @endcode
115///
116/// A success value *can not* be dropped. For example, just calling 'foo(<...>)'
117/// without testing the return value will raise a runtime error, even if foo
118/// returns success.
119///
120/// For Error instances representing failure, you must use either the
121/// handleErrors or handleAllErrors function with a typed handler. E.g.:
122///
123/// @code{.cpp}
124/// class MyErrorInfo : public ErrorInfo<MyErrorInfo> {
125/// // Custom error info.
126/// };
127///
128/// Error foo(<...>) { return make_error<MyErrorInfo>(...); }
129///
130/// auto E = foo(<...>); // <- foo returns failure with MyErrorInfo.
131/// auto NewE =
132/// handleErrors(E,
133/// [](const MyErrorInfo &M) {
134/// // Deal with the error.
135/// },
136/// [](std::unique_ptr<OtherError> M) -> Error {
137/// if (canHandle(*M)) {
138/// // handle error.
139/// return Error::success();
140/// }
141/// // Couldn't handle this error instance. Pass it up the stack.
142/// return Error(std::move(M));
143/// );
144/// // Note - we must check or return NewE in case any of the handlers
145/// // returned a new error.
146/// @endcode
147///
148/// The handleAllErrors function is identical to handleErrors, except
149/// that it has a void return type, and requires all errors to be handled and
150/// no new errors be returned. It prevents errors (assuming they can all be
151/// handled) from having to be bubbled all the way to the top-level.
152///
153/// *All* Error instances must be checked before destruction, even if
154/// they're moved-assigned or constructed from Success values that have already
155/// been checked. This enforces checking through all levels of the call stack.
156class LLVM_NODISCARD[[clang::warn_unused_result]] Error {
157 // ErrorList needs to be able to yank ErrorInfoBase pointers out of this
158 // class to add to the error list.
159 friend class ErrorList;
160
161 // handleErrors needs to be able to set the Checked flag.
162 template <typename... HandlerTs>
163 friend Error handleErrors(Error E, HandlerTs &&... Handlers);
164
165 // Expected<T> needs to be able to steal the payload when constructed from an
166 // error.
167 template <typename T> friend class Expected;
168
169protected:
170 /// Create a success value. Prefer using 'Error::success()' for readability
171 Error() {
172 setPtr(nullptr);
173 setChecked(false);
174 }
175
176public:
177 /// Create a success value.
178 static ErrorSuccess success();
179
180 // Errors are not copy-constructable.
181 Error(const Error &Other) = delete;
182
183 /// Move-construct an error value. The newly constructed error is considered
184 /// unchecked, even if the source error had been checked. The original error
185 /// becomes a checked Success value, regardless of its original state.
186 Error(Error &&Other) {
187 setChecked(true);
188 *this = std::move(Other);
189 }
190
191 /// Create an error value. Prefer using the 'make_error' function, but
192 /// this constructor can be useful when "re-throwing" errors from handlers.
193 Error(std::unique_ptr<ErrorInfoBase> Payload) {
194 setPtr(Payload.release());
195 setChecked(false);
196 }
197
198 // Errors are not copy-assignable.
199 Error &operator=(const Error &Other) = delete;
200
201 /// Move-assign an error value. The current error must represent success, you
202 /// you cannot overwrite an unhandled error. The current error is then
203 /// considered unchecked. The source error becomes a checked success value,
204 /// regardless of its original state.
205 Error &operator=(Error &&Other) {
206 // Don't allow overwriting of unchecked values.
207 assertIsChecked();
208 setPtr(Other.getPtr());
209
210 // This Error is unchecked, even if the source error was checked.
211 setChecked(false);
212
213 // Null out Other's payload and set its checked bit.
214 Other.setPtr(nullptr);
215 Other.setChecked(true);
216
217 return *this;
218 }
219
220 /// Destroy a Error. Fails with a call to abort() if the error is
221 /// unchecked.
222 ~Error() {
223 assertIsChecked();
224 delete getPtr();
225 }
226
227 /// Bool conversion. Returns true if this Error is in a failure state,
228 /// and false if it is in an accept state. If the error is in a Success state
229 /// it will be considered checked.
230 explicit operator bool() {
231 setChecked(getPtr() == nullptr);
232 return getPtr() != nullptr;
233 }
234
235 /// Check whether one error is a subclass of another.
236 template <typename ErrT> bool isA() const {
237 return getPtr() && getPtr()->isA(ErrT::classID());
238 }
239
240 /// Returns the dynamic class id of this error, or null if this is a success
241 /// value.
242 const void* dynamicClassID() const {
243 if (!getPtr())
244 return nullptr;
245 return getPtr()->dynamicClassID();
246 }
247
248private:
249#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
250 // assertIsChecked() happens very frequently, but under normal circumstances
251 // is supposed to be a no-op. So we want it to be inlined, but having a bunch
252 // of debug prints can cause the function to be too large for inlining. So
253 // it's important that we define this function out of line so that it can't be
254 // inlined.
255 LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn))
256 void fatalUncheckedError() const;
257#endif
258
259 void assertIsChecked() {
260#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
261 if (LLVM_UNLIKELY(!getChecked() || getPtr())__builtin_expect((bool)(!getChecked() || getPtr()), false))
262 fatalUncheckedError();
263#endif
264 }
265
266 ErrorInfoBase *getPtr() const {
267 return reinterpret_cast<ErrorInfoBase*>(
268 reinterpret_cast<uintptr_t>(Payload) &
269 ~static_cast<uintptr_t>(0x1));
270 }
271
272 void setPtr(ErrorInfoBase *EI) {
273#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
274 Payload = reinterpret_cast<ErrorInfoBase*>(
275 (reinterpret_cast<uintptr_t>(EI) &
276 ~static_cast<uintptr_t>(0x1)) |
277 (reinterpret_cast<uintptr_t>(Payload) & 0x1));
278#else
279 Payload = EI;
280#endif
281 }
282
283 bool getChecked() const {
284#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
285 return (reinterpret_cast<uintptr_t>(Payload) & 0x1) == 0;
286#else
287 return true;
288#endif
289 }
290
291 void setChecked(bool V) {
292 Payload = reinterpret_cast<ErrorInfoBase*>(
293 (reinterpret_cast<uintptr_t>(Payload) &
294 ~static_cast<uintptr_t>(0x1)) |
295 (V ? 0 : 1));
296 }
297
298 std::unique_ptr<ErrorInfoBase> takePayload() {
299 std::unique_ptr<ErrorInfoBase> Tmp(getPtr());
300 setPtr(nullptr);
301 setChecked(true);
302 return Tmp;
303 }
304
305 ErrorInfoBase *Payload = nullptr;
306};
307
308/// Subclass of Error for the sole purpose of identifying the success path in
309/// the type system. This allows to catch invalid conversion to Expected<T> at
310/// compile time.
311class ErrorSuccess : public Error {};
312
313inline ErrorSuccess Error::success() { return ErrorSuccess(); }
314
315/// Make a Error instance representing failure using the given error info
316/// type.
317template <typename ErrT, typename... ArgTs> Error make_error(ArgTs &&... Args) {
318 return Error(llvm::make_unique<ErrT>(std::forward<ArgTs>(Args)...));
12
Calling 'make_unique'
319}
320
321/// Base class for user error types. Users should declare their error types
322/// like:
323///
324/// class MyError : public ErrorInfo<MyError> {
325/// ....
326/// };
327///
328/// This class provides an implementation of the ErrorInfoBase::kind
329/// method, which is used by the Error RTTI system.
330template <typename ThisErrT, typename ParentErrT = ErrorInfoBase>
331class ErrorInfo : public ParentErrT {
332public:
333 static const void *classID() { return &ThisErrT::ID; }
334
335 const void *dynamicClassID() const override { return &ThisErrT::ID; }
336
337 bool isA(const void *const ClassID) const override {
338 return ClassID == classID() || ParentErrT::isA(ClassID);
339 }
340};
341
342/// Special ErrorInfo subclass representing a list of ErrorInfos.
343/// Instances of this class are constructed by joinError.
344class ErrorList final : public ErrorInfo<ErrorList> {
345 // handleErrors needs to be able to iterate the payload list of an
346 // ErrorList.
347 template <typename... HandlerTs>
348 friend Error handleErrors(Error E, HandlerTs &&... Handlers);
349
350 // joinErrors is implemented in terms of join.
351 friend Error joinErrors(Error, Error);
352
353public:
354 void log(raw_ostream &OS) const override {
355 OS << "Multiple errors:\n";
356 for (auto &ErrPayload : Payloads) {
357 ErrPayload->log(OS);
358 OS << "\n";
359 }
360 }
361
362 std::error_code convertToErrorCode() const override;
363
364 // Used by ErrorInfo::classID.
365 static char ID;
366
367private:
368 ErrorList(std::unique_ptr<ErrorInfoBase> Payload1,
369 std::unique_ptr<ErrorInfoBase> Payload2) {
370 assert(!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() &&(static_cast <bool> (!Payload1->isA<ErrorList>
() && !Payload2->isA<ErrorList>() &&
"ErrorList constructor payloads should be singleton errors")
? void (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/Support/Error.h"
, 371, __extension__ __PRETTY_FUNCTION__))
371 "ErrorList constructor payloads should be singleton errors")(static_cast <bool> (!Payload1->isA<ErrorList>
() && !Payload2->isA<ErrorList>() &&
"ErrorList constructor payloads should be singleton errors")
? void (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/Support/Error.h"
, 371, __extension__ __PRETTY_FUNCTION__))
;
372 Payloads.push_back(std::move(Payload1));
373 Payloads.push_back(std::move(Payload2));
374 }
375
376 static Error join(Error E1, Error E2) {
377 if (!E1)
378 return E2;
379 if (!E2)
380 return E1;
381 if (E1.isA<ErrorList>()) {
382 auto &E1List = static_cast<ErrorList &>(*E1.getPtr());
383 if (E2.isA<ErrorList>()) {
384 auto E2Payload = E2.takePayload();
385 auto &E2List = static_cast<ErrorList &>(*E2Payload);
386 for (auto &Payload : E2List.Payloads)
387 E1List.Payloads.push_back(std::move(Payload));
388 } else
389 E1List.Payloads.push_back(E2.takePayload());
390
391 return E1;
392 }
393 if (E2.isA<ErrorList>()) {
394 auto &E2List = static_cast<ErrorList &>(*E2.getPtr());
395 E2List.Payloads.insert(E2List.Payloads.begin(), E1.takePayload());
396 return E2;
397 }
398 return Error(std::unique_ptr<ErrorList>(
399 new ErrorList(E1.takePayload(), E2.takePayload())));
400 }
401
402 std::vector<std::unique_ptr<ErrorInfoBase>> Payloads;
403};
404
405/// Concatenate errors. The resulting Error is unchecked, and contains the
406/// ErrorInfo(s), if any, contained in E1, followed by the
407/// ErrorInfo(s), if any, contained in E2.
408inline Error joinErrors(Error E1, Error E2) {
409 return ErrorList::join(std::move(E1), std::move(E2));
410}
411
412/// Tagged union holding either a T or a Error.
413///
414/// This class parallels ErrorOr, but replaces error_code with Error. Since
415/// Error cannot be copied, this class replaces getError() with
416/// takeError(). It also adds an bool errorIsA<ErrT>() method for testing the
417/// error class type.
418template <class T> class LLVM_NODISCARD[[clang::warn_unused_result]] Expected {
419 template <class T1> friend class ExpectedAsOutParameter;
420 template <class OtherT> friend class Expected;
421
422 static const bool isRef = std::is_reference<T>::value;
423
424 using wrap = ReferenceStorage<typename std::remove_reference<T>::type>;
425
426 using error_type = std::unique_ptr<ErrorInfoBase>;
427
428public:
429 using storage_type = typename std::conditional<isRef, wrap, T>::type;
430 using value_type = T;
431
432private:
433 using reference = typename std::remove_reference<T>::type &;
434 using const_reference = const typename std::remove_reference<T>::type &;
435 using pointer = typename std::remove_reference<T>::type *;
436 using const_pointer = const typename std::remove_reference<T>::type *;
437
438public:
439 /// Create an Expected<T> error value from the given Error.
440 Expected(Error Err)
441 : HasError(true)
442#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
443 // Expected is unchecked upon construction in Debug builds.
444 , Unchecked(true)
445#endif
446 {
447 assert(Err && "Cannot create Expected<T> from Error success value.")(static_cast <bool> (Err && "Cannot create Expected<T> from Error success value."
) ? void (0) : __assert_fail ("Err && \"Cannot create Expected<T> from Error success value.\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/Support/Error.h"
, 447, __extension__ __PRETTY_FUNCTION__))
;
448 new (getErrorStorage()) error_type(Err.takePayload());
449 }
450
451 /// Forbid to convert from Error::success() implicitly, this avoids having
452 /// Expected<T> foo() { return Error::success(); } which compiles otherwise
453 /// but triggers the assertion above.
454 Expected(ErrorSuccess) = delete;
455
456 /// Create an Expected<T> success value from the given OtherT value, which
457 /// must be convertible to T.
458 template <typename OtherT>
459 Expected(OtherT &&Val,
460 typename std::enable_if<std::is_convertible<OtherT, T>::value>::type
461 * = nullptr)
462 : HasError(false)
463#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
464 // Expected is unchecked upon construction in Debug builds.
465 , Unchecked(true)
466#endif
467 {
468 new (getStorage()) storage_type(std::forward<OtherT>(Val));
469 }
470
471 /// Move construct an Expected<T> value.
472 Expected(Expected &&Other) { moveConstruct(std::move(Other)); }
473
474 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
475 /// must be convertible to T.
476 template <class OtherT>
477 Expected(Expected<OtherT> &&Other,
478 typename std::enable_if<std::is_convertible<OtherT, T>::value>::type
479 * = nullptr) {
480 moveConstruct(std::move(Other));
481 }
482
483 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
484 /// isn't convertible to T.
485 template <class OtherT>
486 explicit Expected(
487 Expected<OtherT> &&Other,
488 typename std::enable_if<!std::is_convertible<OtherT, T>::value>::type * =
489 nullptr) {
490 moveConstruct(std::move(Other));
491 }
492
493 /// Move-assign from another Expected<T>.
494 Expected &operator=(Expected &&Other) {
495 moveAssign(std::move(Other));
496 return *this;
497 }
498
499 /// Destroy an Expected<T>.
500 ~Expected() {
501 assertIsChecked();
502 if (!HasError)
503 getStorage()->~storage_type();
504 else
505 getErrorStorage()->~error_type();
506 }
507
508 /// \brief Return false if there is an error.
509 explicit operator bool() {
510#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
511 Unchecked = HasError;
512#endif
513 return !HasError;
514 }
515
516 /// \brief Returns a reference to the stored T value.
517 reference get() {
518 assertIsChecked();
519 return *getStorage();
520 }
521
522 /// \brief Returns a const reference to the stored T value.
523 const_reference get() const {
524 assertIsChecked();
525 return const_cast<Expected<T> *>(this)->get();
526 }
527
528 /// \brief Check that this Expected<T> is an error of type ErrT.
529 template <typename ErrT> bool errorIsA() const {
530 return HasError && (*getErrorStorage())->template isA<ErrT>();
531 }
532
533 /// \brief Take ownership of the stored error.
534 /// After calling this the Expected<T> is in an indeterminate state that can
535 /// only be safely destructed. No further calls (beside the destructor) should
536 /// be made on the Expected<T> vaule.
537 Error takeError() {
538#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
539 Unchecked = false;
540#endif
541 return HasError ? Error(std::move(*getErrorStorage())) : Error::success();
542 }
543
544 /// \brief Returns a pointer to the stored T value.
545 pointer operator->() {
546 assertIsChecked();
547 return toPointer(getStorage());
548 }
549
550 /// \brief Returns a const pointer to the stored T value.
551 const_pointer operator->() const {
552 assertIsChecked();
553 return toPointer(getStorage());
554 }
555
556 /// \brief Returns a reference to the stored T value.
557 reference operator*() {
558 assertIsChecked();
559 return *getStorage();
560 }
561
562 /// \brief Returns a const reference to the stored T value.
563 const_reference operator*() const {
564 assertIsChecked();
565 return *getStorage();
566 }
567
568private:
569 template <class T1>
570 static bool compareThisIfSameType(const T1 &a, const T1 &b) {
571 return &a == &b;
572 }
573
574 template <class T1, class T2>
575 static bool compareThisIfSameType(const T1 &a, const T2 &b) {
576 return false;
577 }
578
579 template <class OtherT> void moveConstruct(Expected<OtherT> &&Other) {
580 HasError = Other.HasError;
581#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
582 Unchecked = true;
583 Other.Unchecked = false;
584#endif
585
586 if (!HasError)
587 new (getStorage()) storage_type(std::move(*Other.getStorage()));
588 else
589 new (getErrorStorage()) error_type(std::move(*Other.getErrorStorage()));
590 }
591
592 template <class OtherT> void moveAssign(Expected<OtherT> &&Other) {
593 assertIsChecked();
594
595 if (compareThisIfSameType(*this, Other))
596 return;
597
598 this->~Expected();
599 new (this) Expected(std::move(Other));
600 }
601
602 pointer toPointer(pointer Val) { return Val; }
603
604 const_pointer toPointer(const_pointer Val) const { return Val; }
605
606 pointer toPointer(wrap *Val) { return &Val->get(); }
607
608 const_pointer toPointer(const wrap *Val) const { return &Val->get(); }
609
610 storage_type *getStorage() {
611 assert(!HasError && "Cannot get value when an error exists!")(static_cast <bool> (!HasError && "Cannot get value when an error exists!"
) ? void (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/Support/Error.h"
, 611, __extension__ __PRETTY_FUNCTION__))
;
612 return reinterpret_cast<storage_type *>(TStorage.buffer);
613 }
614
615 const storage_type *getStorage() const {
616 assert(!HasError && "Cannot get value when an error exists!")(static_cast <bool> (!HasError && "Cannot get value when an error exists!"
) ? void (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/Support/Error.h"
, 616, __extension__ __PRETTY_FUNCTION__))
;
617 return reinterpret_cast<const storage_type *>(TStorage.buffer);
618 }
619
620 error_type *getErrorStorage() {
621 assert(HasError && "Cannot get error when a value exists!")(static_cast <bool> (HasError && "Cannot get error when a value exists!"
) ? void (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/Support/Error.h"
, 621, __extension__ __PRETTY_FUNCTION__))
;
622 return reinterpret_cast<error_type *>(ErrorStorage.buffer);
623 }
624
625 const error_type *getErrorStorage() const {
626 assert(HasError && "Cannot get error when a value exists!")(static_cast <bool> (HasError && "Cannot get error when a value exists!"
) ? void (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/Support/Error.h"
, 626, __extension__ __PRETTY_FUNCTION__))
;
627 return reinterpret_cast<const error_type *>(ErrorStorage.buffer);
628 }
629
630 // Used by ExpectedAsOutParameter to reset the checked flag.
631 void setUnchecked() {
632#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
633 Unchecked = true;
634#endif
635 }
636
637#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
638 LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn))
639 LLVM_ATTRIBUTE_NOINLINE__attribute__((noinline))
640 void fatalUncheckedExpected() const {
641 dbgs() << "Expected<T> must be checked before access or destruction.\n";
642 if (HasError) {
643 dbgs() << "Unchecked Expected<T> contained error:\n";
644 (*getErrorStorage())->log(dbgs());
645 } else
646 dbgs() << "Expected<T> value was in success state. (Note: Expected<T> "
647 "values in success mode must still be checked prior to being "
648 "destroyed).\n";
649 abort();
650 }
651#endif
652
653 void assertIsChecked() {
654#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
655 if (LLVM_UNLIKELY(Unchecked)__builtin_expect((bool)(Unchecked), false))
656 fatalUncheckedExpected();
657#endif
658 }
659
660 union {
661 AlignedCharArrayUnion<storage_type> TStorage;
662 AlignedCharArrayUnion<error_type> ErrorStorage;
663 };
664 bool HasError : 1;
665#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
666 bool Unchecked : 1;
667#endif
668};
669
670/// Report a serious error, calling any installed error handler. See
671/// ErrorHandling.h.
672LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn)) void report_fatal_error(Error Err,
673 bool gen_crash_diag = true);
674
675/// Report a fatal error if Err is a failure value.
676///
677/// This function can be used to wrap calls to fallible functions ONLY when it
678/// is known that the Error will always be a success value. E.g.
679///
680/// @code{.cpp}
681/// // foo only attempts the fallible operation if DoFallibleOperation is
682/// // true. If DoFallibleOperation is false then foo always returns
683/// // Error::success().
684/// Error foo(bool DoFallibleOperation);
685///
686/// cantFail(foo(false));
687/// @endcode
688inline void cantFail(Error Err, const char *Msg = nullptr) {
689 if (Err) {
690 if (!Msg)
691 Msg = "Failure value returned from cantFail wrapped call";
692 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/Support/Error.h"
, 692)
;
693 }
694}
695
696/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
697/// returns the contained value.
698///
699/// This function can be used to wrap calls to fallible functions ONLY when it
700/// is known that the Error will always be a success value. E.g.
701///
702/// @code{.cpp}
703/// // foo only attempts the fallible operation if DoFallibleOperation is
704/// // true. If DoFallibleOperation is false then foo always returns an int.
705/// Expected<int> foo(bool DoFallibleOperation);
706///
707/// int X = cantFail(foo(false));
708/// @endcode
709template <typename T>
710T cantFail(Expected<T> ValOrErr, const char *Msg = nullptr) {
711 if (ValOrErr)
712 return std::move(*ValOrErr);
713 else {
714 if (!Msg)
715 Msg = "Failure value returned from cantFail wrapped call";
716 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/Support/Error.h"
, 716)
;
717 }
718}
719
720/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
721/// returns the contained reference.
722///
723/// This function can be used to wrap calls to fallible functions ONLY when it
724/// is known that the Error will always be a success value. E.g.
725///
726/// @code{.cpp}
727/// // foo only attempts the fallible operation if DoFallibleOperation is
728/// // true. If DoFallibleOperation is false then foo always returns a Bar&.
729/// Expected<Bar&> foo(bool DoFallibleOperation);
730///
731/// Bar &X = cantFail(foo(false));
732/// @endcode
733template <typename T>
734T& cantFail(Expected<T&> ValOrErr, const char *Msg = nullptr) {
735 if (ValOrErr)
736 return *ValOrErr;
737 else {
738 if (!Msg)
739 Msg = "Failure value returned from cantFail wrapped call";
740 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/Support/Error.h"
, 740)
;
741 }
742}
743
744/// Helper for testing applicability of, and applying, handlers for
745/// ErrorInfo types.
746template <typename HandlerT>
747class ErrorHandlerTraits
748 : public ErrorHandlerTraits<decltype(
749 &std::remove_reference<HandlerT>::type::operator())> {};
750
751// Specialization functions of the form 'Error (const ErrT&)'.
752template <typename ErrT> class ErrorHandlerTraits<Error (&)(ErrT &)> {
753public:
754 static bool appliesTo(const ErrorInfoBase &E) {
755 return E.template isA<ErrT>();
756 }
757
758 template <typename HandlerT>
759 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
760 assert(appliesTo(*E) && "Applying incorrect handler")(static_cast <bool> (appliesTo(*E) && "Applying incorrect handler"
) ? void (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/Support/Error.h"
, 760, __extension__ __PRETTY_FUNCTION__))
;
761 return H(static_cast<ErrT &>(*E));
762 }
763};
764
765// Specialization functions of the form 'void (const ErrT&)'.
766template <typename ErrT> class ErrorHandlerTraits<void (&)(ErrT &)> {
767public:
768 static bool appliesTo(const ErrorInfoBase &E) {
769 return E.template isA<ErrT>();
770 }
771
772 template <typename HandlerT>
773 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
774 assert(appliesTo(*E) && "Applying incorrect handler")(static_cast <bool> (appliesTo(*E) && "Applying incorrect handler"
) ? void (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/Support/Error.h"
, 774, __extension__ __PRETTY_FUNCTION__))
;
775 H(static_cast<ErrT &>(*E));
776 return Error::success();
777 }
778};
779
780/// Specialization for functions of the form 'Error (std::unique_ptr<ErrT>)'.
781template <typename ErrT>
782class ErrorHandlerTraits<Error (&)(std::unique_ptr<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")(static_cast <bool> (appliesTo(*E) && "Applying incorrect handler"
) ? void (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/Support/Error.h"
, 790, __extension__ __PRETTY_FUNCTION__))
;
791 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
792 return H(std::move(SubE));
793 }
794};
795
796/// Specialization for functions of the form 'void (std::unique_ptr<ErrT>)'.
797template <typename ErrT>
798class ErrorHandlerTraits<void (&)(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")(static_cast <bool> (appliesTo(*E) && "Applying incorrect handler"
) ? void (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/Support/Error.h"
, 806, __extension__ __PRETTY_FUNCTION__))
;
807 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
808 H(std::move(SubE));
809 return Error::success();
810 }
811};
812
813// Specialization for member functions of the form 'RetT (const ErrT&)'.
814template <typename C, typename RetT, typename ErrT>
815class ErrorHandlerTraits<RetT (C::*)(ErrT &)>
816 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
817
818// Specialization for member functions of the form 'RetT (const ErrT&) const'.
819template <typename C, typename RetT, typename ErrT>
820class ErrorHandlerTraits<RetT (C::*)(ErrT &) const>
821 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
822
823// Specialization for member functions of the form 'RetT (const ErrT&)'.
824template <typename C, typename RetT, typename ErrT>
825class ErrorHandlerTraits<RetT (C::*)(const ErrT &)>
826 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
827
828// Specialization for member functions of the form 'RetT (const ErrT&) const'.
829template <typename C, typename RetT, typename ErrT>
830class ErrorHandlerTraits<RetT (C::*)(const ErrT &) const>
831 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
832
833/// Specialization for member functions of the form
834/// 'RetT (std::unique_ptr<ErrT>)'.
835template <typename C, typename RetT, typename ErrT>
836class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>)>
837 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
838
839/// Specialization for member functions of the form
840/// 'RetT (std::unique_ptr<ErrT>) const'.
841template <typename C, typename RetT, typename ErrT>
842class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>) const>
843 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
844
845inline Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload) {
846 return Error(std::move(Payload));
847}
848
849template <typename HandlerT, typename... HandlerTs>
850Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload,
851 HandlerT &&Handler, HandlerTs &&... Handlers) {
852 if (ErrorHandlerTraits<HandlerT>::appliesTo(*Payload))
853 return ErrorHandlerTraits<HandlerT>::apply(std::forward<HandlerT>(Handler),
854 std::move(Payload));
855 return handleErrorImpl(std::move(Payload),
856 std::forward<HandlerTs>(Handlers)...);
857}
858
859/// Pass the ErrorInfo(s) contained in E to their respective handlers. Any
860/// unhandled errors (or Errors returned by handlers) are re-concatenated and
861/// returned.
862/// Because this function returns an error, its result must also be checked
863/// or returned. If you intend to handle all errors use handleAllErrors
864/// (which returns void, and will abort() on unhandled errors) instead.
865template <typename... HandlerTs>
866Error handleErrors(Error E, HandlerTs &&... Hs) {
867 if (!E)
868 return Error::success();
869
870 std::unique_ptr<ErrorInfoBase> Payload = E.takePayload();
871
872 if (Payload->isA<ErrorList>()) {
873 ErrorList &List = static_cast<ErrorList &>(*Payload);
874 Error R;
875 for (auto &P : List.Payloads)
876 R = ErrorList::join(
877 std::move(R),
878 handleErrorImpl(std::move(P), std::forward<HandlerTs>(Hs)...));
879 return R;
880 }
881
882 return handleErrorImpl(std::move(Payload), std::forward<HandlerTs>(Hs)...);
883}
884
885/// Behaves the same as handleErrors, except that it requires that all
886/// errors be handled by the given handlers. If any unhandled error remains
887/// after the handlers have run, report_fatal_error() will be called.
888template <typename... HandlerTs>
889void handleAllErrors(Error E, HandlerTs &&... Handlers) {
890 cantFail(handleErrors(std::move(E), std::forward<HandlerTs>(Handlers)...));
891}
892
893/// Check that E is a non-error, then drop it.
894/// If E is an error report_fatal_error will be called.
895inline void handleAllErrors(Error E) {
896 cantFail(std::move(E));
897}
898
899/// Handle any errors (if present) in an Expected<T>, then try a recovery path.
900///
901/// If the incoming value is a success value it is returned unmodified. If it
902/// is a failure value then it the contained error is passed to handleErrors.
903/// If handleErrors is able to handle the error then the RecoveryPath functor
904/// is called to supply the final result. If handleErrors is not able to
905/// handle all errors then the unhandled errors are returned.
906///
907/// This utility enables the follow pattern:
908///
909/// @code{.cpp}
910/// enum FooStrategy { Aggressive, Conservative };
911/// Expected<Foo> foo(FooStrategy S);
912///
913/// auto ResultOrErr =
914/// handleExpected(
915/// foo(Aggressive),
916/// []() { return foo(Conservative); },
917/// [](AggressiveStrategyError&) {
918/// // Implicitly conusme this - we'll recover by using a conservative
919/// // strategy.
920/// });
921///
922/// @endcode
923template <typename T, typename RecoveryFtor, typename... HandlerTs>
924Expected<T> handleExpected(Expected<T> ValOrErr, RecoveryFtor &&RecoveryPath,
925 HandlerTs &&... Handlers) {
926 if (ValOrErr)
927 return ValOrErr;
928
929 if (auto Err = handleErrors(ValOrErr.takeError(),
930 std::forward<HandlerTs>(Handlers)...))
931 return std::move(Err);
932
933 return RecoveryPath();
934}
935
936/// Log all errors (if any) in E to OS. If there are any errors, ErrorBanner
937/// will be printed before the first one is logged. A newline will be printed
938/// after each error.
939///
940/// This is useful in the base level of your program to allow clean termination
941/// (allowing clean deallocation of resources, etc.), while reporting error
942/// information to the user.
943void logAllUnhandledErrors(Error E, raw_ostream &OS, Twine ErrorBanner);
944
945/// Write all error messages (if any) in E to a string. The newline character
946/// is used to separate error messages.
947inline std::string toString(Error E) {
948 SmallVector<std::string, 2> Errors;
949 handleAllErrors(std::move(E), [&Errors](const ErrorInfoBase &EI) {
950 Errors.push_back(EI.message());
951 });
952 return join(Errors.begin(), Errors.end(), "\n");
953}
954
955/// Consume a Error without doing anything. This method should be used
956/// only where an error can be considered a reasonable and expected return
957/// value.
958///
959/// Uses of this method are potentially indicative of design problems: If it's
960/// legitimate to do nothing while processing an "error", the error-producer
961/// might be more clearly refactored to return an Optional<T>.
962inline void consumeError(Error Err) {
963 handleAllErrors(std::move(Err), [](const ErrorInfoBase &) {});
964}
965
966/// Helper for Errors used as out-parameters.
967///
968/// This helper is for use with the Error-as-out-parameter idiom, where an error
969/// is passed to a function or method by reference, rather than being returned.
970/// In such cases it is helpful to set the checked bit on entry to the function
971/// so that the error can be written to (unchecked Errors abort on assignment)
972/// and clear the checked bit on exit so that clients cannot accidentally forget
973/// to check the result. This helper performs these actions automatically using
974/// RAII:
975///
976/// @code{.cpp}
977/// Result foo(Error &Err) {
978/// ErrorAsOutParameter ErrAsOutParam(&Err); // 'Checked' flag set
979/// // <body of foo>
980/// // <- 'Checked' flag auto-cleared when ErrAsOutParam is destructed.
981/// }
982/// @endcode
983///
984/// ErrorAsOutParameter takes an Error* rather than Error& so that it can be
985/// used with optional Errors (Error pointers that are allowed to be null). If
986/// ErrorAsOutParameter took an Error reference, an instance would have to be
987/// created inside every condition that verified that Error was non-null. By
988/// taking an Error pointer we can just create one instance at the top of the
989/// function.
990class ErrorAsOutParameter {
991public:
992 ErrorAsOutParameter(Error *Err) : Err(Err) {
993 // Raise the checked bit if Err is success.
994 if (Err)
995 (void)!!*Err;
996 }
997
998 ~ErrorAsOutParameter() {
999 // Clear the checked bit.
1000 if (Err && !*Err)
1001 *Err = Error::success();
1002 }
1003
1004private:
1005 Error *Err;
1006};
1007
1008/// Helper for Expected<T>s used as out-parameters.
1009///
1010/// See ErrorAsOutParameter.
1011template <typename T>
1012class ExpectedAsOutParameter {
1013public:
1014 ExpectedAsOutParameter(Expected<T> *ValOrErr)
1015 : ValOrErr(ValOrErr) {
1016 if (ValOrErr)
1017 (void)!!*ValOrErr;
1018 }
1019
1020 ~ExpectedAsOutParameter() {
1021 if (ValOrErr)
1022 ValOrErr->setUnchecked();
1023 }
1024
1025private:
1026 Expected<T> *ValOrErr;
1027};
1028
1029/// This class wraps a std::error_code in a Error.
1030///
1031/// This is useful if you're writing an interface that returns a Error
1032/// (or Expected) and you want to call code that still returns
1033/// std::error_codes.
1034class ECError : public ErrorInfo<ECError> {
1035 friend Error errorCodeToError(std::error_code);
1036
1037public:
1038 void setErrorCode(std::error_code EC) { this->EC = EC; }
1039 std::error_code convertToErrorCode() const override { return EC; }
1040 void log(raw_ostream &OS) const override { OS << EC.message(); }
1041
1042 // Used by ErrorInfo::classID.
1043 static char ID;
1044
1045protected:
1046 ECError() = default;
1047 ECError(std::error_code EC) : EC(EC) {}
1048
1049 std::error_code EC;
1050};
1051
1052/// The value returned by this function can be returned from convertToErrorCode
1053/// for Error values where no sensible translation to std::error_code exists.
1054/// It should only be used in this situation, and should never be used where a
1055/// sensible conversion to std::error_code is available, as attempts to convert
1056/// to/from this error will result in a fatal error. (i.e. it is a programmatic
1057///error to try to convert such a value).
1058std::error_code inconvertibleErrorCode();
1059
1060/// Helper for converting an std::error_code to a Error.
1061Error errorCodeToError(std::error_code EC);
1062
1063/// Helper for converting an ECError to a std::error_code.
1064///
1065/// This method requires that Err be Error() or an ECError, otherwise it
1066/// will trigger a call to abort().
1067std::error_code errorToErrorCode(Error Err);
1068
1069/// Convert an ErrorOr<T> to an Expected<T>.
1070template <typename T> Expected<T> errorOrToExpected(ErrorOr<T> &&EO) {
1071 if (auto EC = EO.getError())
1072 return errorCodeToError(EC);
1073 return std::move(*EO);
1074}
1075
1076/// Convert an Expected<T> to an ErrorOr<T>.
1077template <typename T> ErrorOr<T> expectedToErrorOr(Expected<T> &&E) {
1078 if (auto Err = E.takeError())
1079 return errorToErrorCode(std::move(Err));
1080 return std::move(*E);
1081}
1082
1083/// This class wraps a string in an Error.
1084///
1085/// StringError is useful in cases where the client is not expected to be able
1086/// to consume the specific error message programmatically (for example, if the
1087/// error message is to be presented to the user).
1088class StringError : public ErrorInfo<StringError> {
1089public:
1090 static char ID;
1091
1092 StringError(const Twine &S, std::error_code EC);
1093
1094 void log(raw_ostream &OS) const override;
1095 std::error_code convertToErrorCode() const override;
1096
1097 const std::string &getMessage() const { return Msg; }
1098
1099private:
1100 std::string Msg;
1101 std::error_code EC;
1102};
1103
1104/// Helper for check-and-exit error handling.
1105///
1106/// For tool use only. NOT FOR USE IN LIBRARY CODE.
1107///
1108class ExitOnError {
1109public:
1110 /// Create an error on exit helper.
1111 ExitOnError(std::string Banner = "", int DefaultErrorExitCode = 1)
1112 : Banner(std::move(Banner)),
1113 GetExitCode([=](const Error &) { return DefaultErrorExitCode; }) {}
1114
1115 /// Set the banner string for any errors caught by operator().
1116 void setBanner(std::string Banner) { this->Banner = std::move(Banner); }
1117
1118 /// Set the exit-code mapper function.
1119 void setExitCodeMapper(std::function<int(const Error &)> GetExitCode) {
1120 this->GetExitCode = std::move(GetExitCode);
1121 }
1122
1123 /// Check Err. If it's in a failure state log the error(s) and exit.
1124 void operator()(Error Err) const { checkError(std::move(Err)); }
1125
1126 /// Check E. If it's in a success state then return the contained value. If
1127 /// it's in a failure state log the error(s) and exit.
1128 template <typename T> T operator()(Expected<T> &&E) const {
1129 checkError(E.takeError());
1130 return std::move(*E);
1131 }
1132
1133 /// Check E. If it's in a success state then return the contained reference. If
1134 /// it's in a failure state log the error(s) and exit.
1135 template <typename T> T& operator()(Expected<T&> &&E) const {
1136 checkError(E.takeError());
1137 return *E;
1138 }
1139
1140private:
1141 void checkError(Error Err) const {
1142 if (Err) {
1143 int ExitCode = GetExitCode(Err);
1144 logAllUnhandledErrors(std::move(Err), errs(), Banner);
1145 exit(ExitCode);
1146 }
1147 }
1148
1149 std::string Banner;
1150 std::function<int(const Error &)> GetExitCode;
1151};
1152
1153} // end namespace llvm
1154
1155#endif // LLVM_SUPPORT_ERROR_H

/build/llvm-toolchain-snapshot-6.0~svn318693/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/Support/ErrorHandling.h"
25#include <algorithm>
26#include <cassert>
27#include <cstddef>
28#include <cstdint>
29#include <cstdlib>
30#include <functional>
31#include <initializer_list>
32#include <iterator>
33#include <limits>
34#include <memory>
35#include <tuple>
36#include <type_traits>
37#include <utility>
38
39namespace llvm {
40
41// Only used by compiler if both template types are the same. Useful when
42// using SFINAE to test for the existence of member functions.
43template <typename T, T> struct SameType;
44
45namespace detail {
46
47template <typename RangeT>
48using IterOfRange = decltype(std::begin(std::declval<RangeT &>()));
49
50template <typename RangeT>
51using ValueOfRange = typename std::remove_reference<decltype(
52 *std::begin(std::declval<RangeT &>()))>::type;
53
54} // end namespace detail
55
56//===----------------------------------------------------------------------===//
57// Extra additions to <functional>
58//===----------------------------------------------------------------------===//
59
60template <class Ty> struct identity {
61 using argument_type = Ty;
62
63 Ty &operator()(Ty &self) const {
64 return self;
65 }
66 const Ty &operator()(const Ty &self) const {
67 return self;
68 }
69};
70
71template <class Ty> struct less_ptr {
72 bool operator()(const Ty* left, const Ty* right) const {
73 return *left < *right;
74 }
75};
76
77template <class Ty> struct greater_ptr {
78 bool operator()(const Ty* left, const Ty* right) const {
79 return *right < *left;
80 }
81};
82
83/// An efficient, type-erasing, non-owning reference to a callable. This is
84/// intended for use as the type of a function parameter that is not used
85/// after the function in question returns.
86///
87/// This class does not own the callable, so it is not in general safe to store
88/// a function_ref.
89template<typename Fn> class function_ref;
90
91template<typename Ret, typename ...Params>
92class function_ref<Ret(Params...)> {
93 Ret (*callback)(intptr_t callable, Params ...params) = nullptr;
94 intptr_t callable;
95
96 template<typename Callable>
97 static Ret callback_fn(intptr_t callable, Params ...params) {
98 return (*reinterpret_cast<Callable*>(callable))(
99 std::forward<Params>(params)...);
100 }
101
102public:
103 function_ref() = default;
104
105 template <typename Callable>
106 function_ref(Callable &&callable,
107 typename std::enable_if<
108 !std::is_same<typename std::remove_reference<Callable>::type,
109 function_ref>::value>::type * = nullptr)
110 : callback(callback_fn<typename std::remove_reference<Callable>::type>),
111 callable(reinterpret_cast<intptr_t>(&callable)) {}
112
113 Ret operator()(Params ...params) const {
114 return callback(callable, std::forward<Params>(params)...);
115 }
116
117 operator bool() const { return callback; }
118};
119
120// deleter - Very very very simple method that is used to invoke operator
121// delete on something. It is used like this:
122//
123// for_each(V.begin(), B.end(), deleter<Interval>);
124template <class T>
125inline void deleter(T *Ptr) {
126 delete Ptr;
127}
128
129//===----------------------------------------------------------------------===//
130// Extra additions to <iterator>
131//===----------------------------------------------------------------------===//
132
133// mapped_iterator - This is a simple iterator adapter that causes a function to
134// be applied whenever operator* is invoked on the iterator.
135
136template <typename ItTy, typename FuncTy,
137 typename FuncReturnTy =
138 decltype(std::declval<FuncTy>()(*std::declval<ItTy>()))>
139class mapped_iterator
140 : public iterator_adaptor_base<
141 mapped_iterator<ItTy, FuncTy>, ItTy,
142 typename std::iterator_traits<ItTy>::iterator_category,
143 typename std::remove_reference<FuncReturnTy>::type> {
144public:
145 mapped_iterator(ItTy U, FuncTy F)
146 : mapped_iterator::iterator_adaptor_base(std::move(U)), F(std::move(F)) {}
147
148 ItTy getCurrent() { return this->I; }
149
150 FuncReturnTy operator*() { return F(*this->I); }
151
152private:
153 FuncTy F;
154};
155
156// map_iterator - Provide a convenient way to create mapped_iterators, just like
157// make_pair is useful for creating pairs...
158template <class ItTy, class FuncTy>
159inline mapped_iterator<ItTy, FuncTy> map_iterator(ItTy I, FuncTy F) {
160 return mapped_iterator<ItTy, FuncTy>(std::move(I), std::move(F));
161}
162
163/// Helper to determine if type T has a member called rbegin().
164template <typename Ty> class has_rbegin_impl {
165 using yes = char[1];
166 using no = char[2];
167
168 template <typename Inner>
169 static yes& test(Inner *I, decltype(I->rbegin()) * = nullptr);
170
171 template <typename>
172 static no& test(...);
173
174public:
175 static const bool value = sizeof(test<Ty>(nullptr)) == sizeof(yes);
176};
177
178/// Metafunction to determine if T& or T has a member called rbegin().
179template <typename Ty>
180struct has_rbegin : has_rbegin_impl<typename std::remove_reference<Ty>::type> {
181};
182
183// Returns an iterator_range over the given container which iterates in reverse.
184// Note that the container must have rbegin()/rend() methods for this to work.
185template <typename ContainerTy>
186auto reverse(ContainerTy &&C,
187 typename std::enable_if<has_rbegin<ContainerTy>::value>::type * =
188 nullptr) -> decltype(make_range(C.rbegin(), C.rend())) {
189 return make_range(C.rbegin(), C.rend());
190}
191
192// Returns a std::reverse_iterator wrapped around the given iterator.
193template <typename IteratorTy>
194std::reverse_iterator<IteratorTy> make_reverse_iterator(IteratorTy It) {
195 return std::reverse_iterator<IteratorTy>(It);
196}
197
198// Returns an iterator_range over the given container which iterates in reverse.
199// Note that the container must have begin()/end() methods which return
200// bidirectional iterators for this to work.
201template <typename ContainerTy>
202auto reverse(
203 ContainerTy &&C,
204 typename std::enable_if<!has_rbegin<ContainerTy>::value>::type * = nullptr)
205 -> decltype(make_range(llvm::make_reverse_iterator(std::end(C)),
206 llvm::make_reverse_iterator(std::begin(C)))) {
207 return make_range(llvm::make_reverse_iterator(std::end(C)),
208 llvm::make_reverse_iterator(std::begin(C)));
209}
210
211/// An iterator adaptor that filters the elements of given inner iterators.
212///
213/// The predicate parameter should be a callable object that accepts the wrapped
214/// iterator's reference type and returns a bool. When incrementing or
215/// decrementing the iterator, it will call the predicate on each element and
216/// skip any where it returns false.
217///
218/// \code
219/// int A[] = { 1, 2, 3, 4 };
220/// auto R = make_filter_range(A, [](int N) { return N % 2 == 1; });
221/// // R contains { 1, 3 }.
222/// \endcode
223template <typename WrappedIteratorT, typename PredicateT>
224class filter_iterator
225 : public iterator_adaptor_base<
226 filter_iterator<WrappedIteratorT, PredicateT>, WrappedIteratorT,
227 typename std::common_type<
228 std::forward_iterator_tag,
229 typename std::iterator_traits<
230 WrappedIteratorT>::iterator_category>::type> {
231 using BaseT = iterator_adaptor_base<
232 filter_iterator<WrappedIteratorT, PredicateT>, WrappedIteratorT,
233 typename std::common_type<
234 std::forward_iterator_tag,
235 typename std::iterator_traits<WrappedIteratorT>::iterator_category>::
236 type>;
237
238 struct PayloadType {
239 WrappedIteratorT End;
240 PredicateT Pred;
241 };
242
243 Optional<PayloadType> Payload;
244
245 void findNextValid() {
246 assert(Payload && "Payload should be engaged when findNextValid is called")(static_cast <bool> (Payload && "Payload should be engaged when findNextValid is called"
) ? void (0) : __assert_fail ("Payload && \"Payload should be engaged when findNextValid is called\""
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/ADT/STLExtras.h"
, 246, __extension__ __PRETTY_FUNCTION__))
;
247 while (this->I != Payload->End && !Payload->Pred(*this->I))
248 BaseT::operator++();
249 }
250
251 // Construct the begin iterator. The begin iterator requires to know where end
252 // is, so that it can properly stop when it hits end.
253 filter_iterator(WrappedIteratorT Begin, WrappedIteratorT End, PredicateT Pred)
254 : BaseT(std::move(Begin)),
255 Payload(PayloadType{std::move(End), std::move(Pred)}) {
256 findNextValid();
257 }
258
259 // Construct the end iterator. It's not incrementable, so Payload doesn't
260 // have to be engaged.
261 filter_iterator(WrappedIteratorT End) : BaseT(End) {}
262
263public:
264 using BaseT::operator++;
265
266 filter_iterator &operator++() {
267 BaseT::operator++();
268 findNextValid();
269 return *this;
270 }
271
272 template <typename RT, typename PT>
273 friend iterator_range<filter_iterator<detail::IterOfRange<RT>, PT>>
274 make_filter_range(RT &&, PT);
275};
276
277/// Convenience function that takes a range of elements and a predicate,
278/// and return a new filter_iterator range.
279///
280/// FIXME: Currently if RangeT && is a rvalue reference to a temporary, the
281/// lifetime of that temporary is not kept by the returned range object, and the
282/// temporary is going to be dropped on the floor after the make_iterator_range
283/// full expression that contains this function call.
284template <typename RangeT, typename PredicateT>
285iterator_range<filter_iterator<detail::IterOfRange<RangeT>, PredicateT>>
286make_filter_range(RangeT &&Range, PredicateT Pred) {
287 using FilterIteratorT =
288 filter_iterator<detail::IterOfRange<RangeT>, PredicateT>;
289 return make_range(FilterIteratorT(std::begin(std::forward<RangeT>(Range)),
290 std::end(std::forward<RangeT>(Range)),
291 std::move(Pred)),
292 FilterIteratorT(std::end(std::forward<RangeT>(Range))));
293}
294
295// forward declarations required by zip_shortest/zip_first
296template <typename R, typename UnaryPredicate>
297bool all_of(R &&range, UnaryPredicate P);
298
299template <size_t... I> struct index_sequence;
300
301template <class... Ts> struct index_sequence_for;
302
303namespace detail {
304
305using std::declval;
306
307// We have to alias this since inlining the actual type at the usage site
308// in the parameter list of iterator_facade_base<> below ICEs MSVC 2017.
309template<typename... Iters> struct ZipTupleType {
310 using type = std::tuple<decltype(*declval<Iters>())...>;
311};
312
313template <typename ZipType, typename... Iters>
314using zip_traits = iterator_facade_base<
315 ZipType, typename std::common_type<std::bidirectional_iterator_tag,
316 typename std::iterator_traits<
317 Iters>::iterator_category...>::type,
318 // ^ TODO: Implement random access methods.
319 typename ZipTupleType<Iters...>::type,
320 typename std::iterator_traits<typename std::tuple_element<
321 0, std::tuple<Iters...>>::type>::difference_type,
322 // ^ FIXME: This follows boost::make_zip_iterator's assumption that all
323 // inner iterators have the same difference_type. It would fail if, for
324 // instance, the second field's difference_type were non-numeric while the
325 // first is.
326 typename ZipTupleType<Iters...>::type *,
327 typename ZipTupleType<Iters...>::type>;
328
329template <typename ZipType, typename... Iters>
330struct zip_common : public zip_traits<ZipType, Iters...> {
331 using Base = zip_traits<ZipType, Iters...>;
332 using value_type = typename Base::value_type;
333
334 std::tuple<Iters...> iterators;
335
336protected:
337 template <size_t... Ns> value_type deref(index_sequence<Ns...>) const {
338 return value_type(*std::get<Ns>(iterators)...);
339 }
340
341 template <size_t... Ns>
342 decltype(iterators) tup_inc(index_sequence<Ns...>) const {
343 return std::tuple<Iters...>(std::next(std::get<Ns>(iterators))...);
344 }
345
346 template <size_t... Ns>
347 decltype(iterators) tup_dec(index_sequence<Ns...>) const {
348 return std::tuple<Iters...>(std::prev(std::get<Ns>(iterators))...);
349 }
350
351public:
352 zip_common(Iters &&... ts) : iterators(std::forward<Iters>(ts)...) {}
353
354 value_type operator*() { return deref(index_sequence_for<Iters...>{}); }
355
356 const value_type operator*() const {
357 return deref(index_sequence_for<Iters...>{});
358 }
359
360 ZipType &operator++() {
361 iterators = tup_inc(index_sequence_for<Iters...>{});
362 return *reinterpret_cast<ZipType *>(this);
363 }
364
365 ZipType &operator--() {
366 static_assert(Base::IsBidirectional,
367 "All inner iterators must be at least bidirectional.");
368 iterators = tup_dec(index_sequence_for<Iters...>{});
369 return *reinterpret_cast<ZipType *>(this);
370 }
371};
372
373template <typename... Iters>
374struct zip_first : public zip_common<zip_first<Iters...>, Iters...> {
375 using Base = zip_common<zip_first<Iters...>, Iters...>;
376
377 bool operator==(const zip_first<Iters...> &other) const {
378 return std::get<0>(this->iterators) == std::get<0>(other.iterators);
379 }
380
381 zip_first(Iters &&... ts) : Base(std::forward<Iters>(ts)...) {}
382};
383
384template <typename... Iters>
385class zip_shortest : public zip_common<zip_shortest<Iters...>, Iters...> {
386 template <size_t... Ns>
387 bool test(const zip_shortest<Iters...> &other, index_sequence<Ns...>) const {
388 return all_of(std::initializer_list<bool>{std::get<Ns>(this->iterators) !=
389 std::get<Ns>(other.iterators)...},
390 identity<bool>{});
391 }
392
393public:
394 using Base = zip_common<zip_shortest<Iters...>, Iters...>;
395
396 zip_shortest(Iters &&... ts) : Base(std::forward<Iters>(ts)...) {}
397
398 bool operator==(const zip_shortest<Iters...> &other) const {
399 return !test(other, index_sequence_for<Iters...>{});
400 }
401};
402
403template <template <typename...> class ItType, typename... Args> class zippy {
404public:
405 using iterator = ItType<decltype(std::begin(std::declval<Args>()))...>;
406 using iterator_category = typename iterator::iterator_category;
407 using value_type = typename iterator::value_type;
408 using difference_type = typename iterator::difference_type;
409 using pointer = typename iterator::pointer;
410 using reference = typename iterator::reference;
411
412private:
413 std::tuple<Args...> ts;
414
415 template <size_t... Ns> iterator begin_impl(index_sequence<Ns...>) const {
416 return iterator(std::begin(std::get<Ns>(ts))...);
417 }
418 template <size_t... Ns> iterator end_impl(index_sequence<Ns...>) const {
419 return iterator(std::end(std::get<Ns>(ts))...);
420 }
421
422public:
423 zippy(Args &&... ts_) : ts(std::forward<Args>(ts_)...) {}
424
425 iterator begin() const { return begin_impl(index_sequence_for<Args...>{}); }
426 iterator end() const { return end_impl(index_sequence_for<Args...>{}); }
427};
428
429} // end namespace detail
430
431/// zip iterator for two or more iteratable types.
432template <typename T, typename U, typename... Args>
433detail::zippy<detail::zip_shortest, T, U, Args...> zip(T &&t, U &&u,
434 Args &&... args) {
435 return detail::zippy<detail::zip_shortest, T, U, Args...>(
436 std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
437}
438
439/// zip iterator that, for the sake of efficiency, assumes the first iteratee to
440/// be the shortest.
441template <typename T, typename U, typename... Args>
442detail::zippy<detail::zip_first, T, U, Args...> zip_first(T &&t, U &&u,
443 Args &&... args) {
444 return detail::zippy<detail::zip_first, T, U, Args...>(
445 std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
446}
447
448/// Iterator wrapper that concatenates sequences together.
449///
450/// This can concatenate different iterators, even with different types, into
451/// a single iterator provided the value types of all the concatenated
452/// iterators expose `reference` and `pointer` types that can be converted to
453/// `ValueT &` and `ValueT *` respectively. It doesn't support more
454/// interesting/customized pointer or reference types.
455///
456/// Currently this only supports forward or higher iterator categories as
457/// inputs and always exposes a forward iterator interface.
458template <typename ValueT, typename... IterTs>
459class concat_iterator
460 : public iterator_facade_base<concat_iterator<ValueT, IterTs...>,
461 std::forward_iterator_tag, ValueT> {
462 using BaseT = typename concat_iterator::iterator_facade_base;
463
464 /// We store both the current and end iterators for each concatenated
465 /// sequence in a tuple of pairs.
466 ///
467 /// Note that something like iterator_range seems nice at first here, but the
468 /// range properties are of little benefit and end up getting in the way
469 /// because we need to do mutation on the current iterators.
470 std::tuple<std::pair<IterTs, IterTs>...> IterPairs;
471
472 /// Attempts to increment a specific iterator.
473 ///
474 /// Returns true if it was able to increment the iterator. Returns false if
475 /// the iterator is already at the end iterator.
476 template <size_t Index> bool incrementHelper() {
477 auto &IterPair = std::get<Index>(IterPairs);
478 if (IterPair.first == IterPair.second)
479 return false;
480
481 ++IterPair.first;
482 return true;
483 }
484
485 /// Increments the first non-end iterator.
486 ///
487 /// It is an error to call this with all iterators at the end.
488 template <size_t... Ns> void increment(index_sequence<Ns...>) {
489 // Build a sequence of functions to increment each iterator if possible.
490 bool (concat_iterator::*IncrementHelperFns[])() = {
491 &concat_iterator::incrementHelper<Ns>...};
492
493 // Loop over them, and stop as soon as we succeed at incrementing one.
494 for (auto &IncrementHelperFn : IncrementHelperFns)
495 if ((this->*IncrementHelperFn)())
496 return;
497
498 llvm_unreachable("Attempted to increment an end concat iterator!")::llvm::llvm_unreachable_internal("Attempted to increment an end concat iterator!"
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/ADT/STLExtras.h"
, 498)
;
499 }
500
501 /// Returns null if the specified iterator is at the end. Otherwise,
502 /// dereferences the iterator and returns the address of the resulting
503 /// reference.
504 template <size_t Index> ValueT *getHelper() const {
505 auto &IterPair = std::get<Index>(IterPairs);
506 if (IterPair.first == IterPair.second)
507 return nullptr;
508
509 return &*IterPair.first;
510 }
511
512 /// Finds the first non-end iterator, dereferences, and returns the resulting
513 /// reference.
514 ///
515 /// It is an error to call this with all iterators at the end.
516 template <size_t... Ns> ValueT &get(index_sequence<Ns...>) const {
517 // Build a sequence of functions to get from iterator if possible.
518 ValueT *(concat_iterator::*GetHelperFns[])() const = {
519 &concat_iterator::getHelper<Ns>...};
520
521 // Loop over them, and return the first result we find.
522 for (auto &GetHelperFn : GetHelperFns)
523 if (ValueT *P = (this->*GetHelperFn)())
524 return *P;
525
526 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-6.0~svn318693/include/llvm/ADT/STLExtras.h"
, 526)
;
527 }
528
529public:
530 /// Constructs an iterator from a squence of ranges.
531 ///
532 /// We need the full range to know how to switch between each of the
533 /// iterators.
534 template <typename... RangeTs>
535 explicit concat_iterator(RangeTs &&... Ranges)
536 : IterPairs({std::begin(Ranges), std::end(Ranges)}...) {}
537
538 using BaseT::operator++;
539
540 concat_iterator &operator++() {
541 increment(index_sequence_for<IterTs...>());
542 return *this;
543 }
544
545 ValueT &operator*() const { return get(index_sequence_for<IterTs...>()); }
546
547 bool operator==(const concat_iterator &RHS) const {
548 return IterPairs == RHS.IterPairs;
549 }
550};
551
552namespace detail {
553
554/// Helper to store a sequence of ranges being concatenated and access them.
555///
556/// This is designed to facilitate providing actual storage when temporaries
557/// are passed into the constructor such that we can use it as part of range
558/// based for loops.
559template <typename ValueT, typename... RangeTs> class concat_range {
560public:
561 using iterator =
562 concat_iterator<ValueT,
563 decltype(std::begin(std::declval<RangeTs &>()))...>;
564
565private:
566 std::tuple<RangeTs...> Ranges;
567
568 template <size_t... Ns> iterator begin_impl(index_sequence<Ns...>) {
569 return iterator(std::get<Ns>(Ranges)...);
570 }
571 template <size_t... Ns> iterator end_impl(index_sequence<Ns...>) {
572 return iterator(make_range(std::end(std::get<Ns>(Ranges)),
573 std::end(std::get<Ns>(Ranges)))...);
574 }
575
576public:
577 concat_range(RangeTs &&... Ranges)
578 : Ranges(std::forward<RangeTs>(Ranges)...) {}
579
580 iterator begin() { return begin_impl(index_sequence_for<RangeTs...>{}); }
581 iterator end() { return end_impl(index_sequence_for<RangeTs...>{}); }
582};
583
584} // end namespace detail
585
586/// Concatenated range across two or more ranges.
587///
588/// The desired value type must be explicitly specified.
589template <typename ValueT, typename... RangeTs>
590detail::concat_range<ValueT, RangeTs...> concat(RangeTs &&... Ranges) {
591 static_assert(sizeof...(RangeTs) > 1,
592 "Need more than one range to concatenate!");
593 return detail::concat_range<ValueT, RangeTs...>(
594 std::forward<RangeTs>(Ranges)...);
595}
596
597//===----------------------------------------------------------------------===//
598// Extra additions to <utility>
599//===----------------------------------------------------------------------===//
600
601/// \brief Function object to check whether the first component of a std::pair
602/// compares less than the first component of another std::pair.
603struct less_first {
604 template <typename T> bool operator()(const T &lhs, const T &rhs) const {
605 return lhs.first < rhs.first;
606 }
607};
608
609/// \brief Function object to check whether the second component of a std::pair
610/// compares less than the second component of another std::pair.
611struct less_second {
612 template <typename T> bool operator()(const T &lhs, const T &rhs) const {
613 return lhs.second < rhs.second;
614 }
615};
616
617// A subset of N3658. More stuff can be added as-needed.
618
619/// \brief Represents a compile-time sequence of integers.
620template <class T, T... I> struct integer_sequence {
621 using value_type = T;
622
623 static constexpr size_t size() { return sizeof...(I); }
624};
625
626/// \brief Alias for the common case of a sequence of size_ts.
627template <size_t... I>
628struct index_sequence : integer_sequence<std::size_t, I...> {};
629
630template <std::size_t N, std::size_t... I>
631struct build_index_impl : build_index_impl<N - 1, N - 1, I...> {};
632template <std::size_t... I>
633struct build_index_impl<0, I...> : index_sequence<I...> {};
634
635/// \brief Creates a compile-time integer sequence for a parameter pack.
636template <class... Ts>
637struct index_sequence_for : build_index_impl<sizeof...(Ts)> {};
638
639/// Utility type to build an inheritance chain that makes it easy to rank
640/// overload candidates.
641template <int N> struct rank : rank<N - 1> {};
642template <> struct rank<0> {};
643
644/// \brief traits class for checking whether type T is one of any of the given
645/// types in the variadic list.
646template <typename T, typename... Ts> struct is_one_of {
647 static const bool value = false;
648};
649
650template <typename T, typename U, typename... Ts>
651struct is_one_of<T, U, Ts...> {
652 static const bool value =
653 std::is_same<T, U>::value || is_one_of<T, Ts...>::value;
654};
655
656/// \brief traits class for checking whether type T is a base class for all
657/// the given types in the variadic list.
658template <typename T, typename... Ts> struct are_base_of {
659 static const bool value = true;
660};
661
662template <typename T, typename U, typename... Ts>
663struct are_base_of<T, U, Ts...> {
664 static const bool value =
665 std::is_base_of<T, U>::value && are_base_of<T, Ts...>::value;
666};
667
668//===----------------------------------------------------------------------===//
669// Extra additions for arrays
670//===----------------------------------------------------------------------===//
671
672/// Find the length of an array.
673template <class T, std::size_t N>
674constexpr inline size_t array_lengthof(T (&)[N]) {
675 return N;
676}
677
678/// Adapt std::less<T> for array_pod_sort.
679template<typename T>
680inline int array_pod_sort_comparator(const void *P1, const void *P2) {
681 if (std::less<T>()(*reinterpret_cast<const T*>(P1),
682 *reinterpret_cast<const T*>(P2)))
683 return -1;
684 if (std::less<T>()(*reinterpret_cast<const T*>(P2),
685 *reinterpret_cast<const T*>(P1)))
686 return 1;
687 return 0;
688}
689
690/// get_array_pod_sort_comparator - This is an internal helper function used to
691/// get type deduction of T right.
692template<typename T>
693inline int (*get_array_pod_sort_comparator(const T &))
694 (const void*, const void*) {
695 return array_pod_sort_comparator<T>;
696}
697
698/// array_pod_sort - This sorts an array with the specified start and end
699/// extent. This is just like std::sort, except that it calls qsort instead of
700/// using an inlined template. qsort is slightly slower than std::sort, but
701/// most sorts are not performance critical in LLVM and std::sort has to be
702/// template instantiated for each type, leading to significant measured code
703/// bloat. This function should generally be used instead of std::sort where
704/// possible.
705///
706/// This function assumes that you have simple POD-like types that can be
707/// compared with std::less and can be moved with memcpy. If this isn't true,
708/// you should use std::sort.
709///
710/// NOTE: If qsort_r were portable, we could allow a custom comparator and
711/// default to std::less.
712template<class IteratorTy>
713inline void array_pod_sort(IteratorTy Start, IteratorTy End) {
714 // Don't inefficiently call qsort with one element or trigger undefined
715 // behavior with an empty sequence.
716 auto NElts = End - Start;
717 if (NElts <= 1) return;
718 qsort(&*Start, NElts, sizeof(*Start), get_array_pod_sort_comparator(*Start));
719}
720
721template <class IteratorTy>
722inline void array_pod_sort(
723 IteratorTy Start, IteratorTy End,
724 int (*Compare)(
725 const typename std::iterator_traits<IteratorTy>::value_type *,
726 const typename std::iterator_traits<IteratorTy>::value_type *)) {
727 // Don't inefficiently call qsort with one element or trigger undefined
728 // behavior with an empty sequence.
729 auto NElts = End - Start;
730 if (NElts <= 1) return;
731 qsort(&*Start, NElts, sizeof(*Start),
732 reinterpret_cast<int (*)(const void *, const void *)>(Compare));
733}
734
735//===----------------------------------------------------------------------===//
736// Extra additions to <algorithm>
737//===----------------------------------------------------------------------===//
738
739/// For a container of pointers, deletes the pointers and then clears the
740/// container.
741template<typename Container>
742void DeleteContainerPointers(Container &C) {
743 for (auto V : C)
744 delete V;
745 C.clear();
746}
747
748/// In a container of pairs (usually a map) whose second element is a pointer,
749/// deletes the second elements and then clears the container.
750template<typename Container>
751void DeleteContainerSeconds(Container &C) {
752 for (auto &V : C)
753 delete V.second;
754 C.clear();
755}
756
757/// Provide wrappers to std::for_each which take ranges instead of having to
758/// pass begin/end explicitly.
759template <typename R, typename UnaryPredicate>
760UnaryPredicate for_each(R &&Range, UnaryPredicate P) {
761 return std::for_each(std::begin(Range), std::end(Range), P);
762}
763
764/// Provide wrappers to std::all_of which take ranges instead of having to pass
765/// begin/end explicitly.
766template <typename R, typename UnaryPredicate>
767bool all_of(R &&Range, UnaryPredicate P) {
768 return std::all_of(std::begin(Range), std::end(Range), P);
769}
770
771/// Provide wrappers to std::any_of which take ranges instead of having to pass
772/// begin/end explicitly.
773template <typename R, typename UnaryPredicate>
774bool any_of(R &&Range, UnaryPredicate P) {
775 return std::any_of(std::begin(Range), std::end(Range), P);
776}
777
778/// Provide wrappers to std::none_of which take ranges instead of having to pass
779/// begin/end explicitly.
780template <typename R, typename UnaryPredicate>
781bool none_of(R &&Range, UnaryPredicate P) {
782 return std::none_of(std::begin(Range), std::end(Range), P);
783}
784
785/// Provide wrappers to std::find which take ranges instead of having to pass
786/// begin/end explicitly.
787template <typename R, typename T>
788auto find(R &&Range, const T &Val) -> decltype(std::begin(Range)) {
789 return std::find(std::begin(Range), std::end(Range), Val);
790}
791
792/// Provide wrappers to std::find_if which take ranges instead of having to pass
793/// begin/end explicitly.
794template <typename R, typename UnaryPredicate>
795auto find_if(R &&Range, UnaryPredicate P) -> decltype(std::begin(Range)) {
796 return std::find_if(std::begin(Range), std::end(Range), P);
797}
798
799template <typename R, typename UnaryPredicate>
800auto find_if_not(R &&Range, UnaryPredicate P) -> decltype(std::begin(Range)) {
801 return std::find_if_not(std::begin(Range), std::end(Range), P);
802}
803
804/// Provide wrappers to std::remove_if which take ranges instead of having to
805/// pass begin/end explicitly.
806template <typename R, typename UnaryPredicate>
807auto remove_if(R &&Range, UnaryPredicate P) -> decltype(std::begin(Range)) {
808 return std::remove_if(std::begin(Range), std::end(Range), P);
809}
810
811/// Provide wrappers to std::copy_if which take ranges instead of having to
812/// pass begin/end explicitly.
813template <typename R, typename OutputIt, typename UnaryPredicate>
814OutputIt copy_if(R &&Range, OutputIt Out, UnaryPredicate P) {
815 return std::copy_if(std::begin(Range), std::end(Range), Out, P);
816}
817
818/// Wrapper function around std::find to detect if an element exists
819/// in a container.
820template <typename R, typename E>
821bool is_contained(R &&Range, const E &Element) {
822 return std::find(std::begin(Range), std::end(Range), Element) !=
823 std::end(Range);
824}
825
826/// Wrapper function around std::count to count the number of times an element
827/// \p Element occurs in the given range \p Range.
828template <typename R, typename E>
829auto count(R &&Range, const E &Element) -> typename std::iterator_traits<
830 decltype(std::begin(Range))>::difference_type {
831 return std::count(std::begin(Range), std::end(Range), Element);
832}
833
834/// Wrapper function around std::count_if to count the number of times an
835/// element satisfying a given predicate occurs in a range.
836template <typename R, typename UnaryPredicate>
837auto count_if(R &&Range, UnaryPredicate P) -> typename std::iterator_traits<
838 decltype(std::begin(Range))>::difference_type {
839 return std::count_if(std::begin(Range), std::end(Range), P);
840}
841
842/// Wrapper function around std::transform to apply a function to a range and
843/// store the result elsewhere.
844template <typename R, typename OutputIt, typename UnaryPredicate>
845OutputIt transform(R &&Range, OutputIt d_first, UnaryPredicate P) {
846 return std::transform(std::begin(Range), std::end(Range), d_first, P);
847}
848
849/// Provide wrappers to std::partition which take ranges instead of having to
850/// pass begin/end explicitly.
851template <typename R, typename UnaryPredicate>
852auto partition(R &&Range, UnaryPredicate P) -> decltype(std::begin(Range)) {
853 return std::partition(std::begin(Range), std::end(Range), P);
854}
855
856/// Provide wrappers to std::lower_bound which take ranges instead of having to
857/// pass begin/end explicitly.
858template <typename R, typename ForwardIt>
859auto lower_bound(R &&Range, ForwardIt I) -> decltype(std::begin(Range)) {
860 return std::lower_bound(std::begin(Range), std::end(Range), I);
861}
862
863/// \brief Given a range of type R, iterate the entire range and return a
864/// SmallVector with elements of the vector. This is useful, for example,
865/// when you want to iterate a range and then sort the results.
866template <unsigned Size, typename R>
867SmallVector<typename std::remove_const<detail::ValueOfRange<R>>::type, Size>
868to_vector(R &&Range) {
869 return {std::begin(Range), std::end(Range)};
870}
871
872/// Provide a container algorithm similar to C++ Library Fundamentals v2's
873/// `erase_if` which is equivalent to:
874///
875/// C.erase(remove_if(C, pred), C.end());
876///
877/// This version works for any container with an erase method call accepting
878/// two iterators.
879template <typename Container, typename UnaryPredicate>
880void erase_if(Container &C, UnaryPredicate P) {
881 C.erase(remove_if(C, P), C.end());
882}
883
884//===----------------------------------------------------------------------===//
885// Extra additions to <memory>
886//===----------------------------------------------------------------------===//
887
888// Implement make_unique according to N3656.
889
890/// \brief Constructs a `new T()` with the given args and returns a
891/// `unique_ptr<T>` which owns the object.
892///
893/// Example:
894///
895/// auto p = make_unique<int>();
896/// auto p = make_unique<std::tuple<int, int>>(0, 1);
897template <class T, class... Args>
898typename std::enable_if<!std::is_array<T>::value, std::unique_ptr<T>>::type
899make_unique(Args &&... args) {
900 return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
13
Calling 'forward'
14
Returning from 'forward'
15
2nd function call argument is an uninitialized value
901}
902
903/// \brief Constructs a `new T[n]` with the given args and returns a
904/// `unique_ptr<T[]>` which owns the object.
905///
906/// \param n size of the new array.
907///
908/// Example:
909///
910/// auto p = make_unique<int[]>(2); // value-initializes the array with 0's.
911template <class T>
912typename std::enable_if<std::is_array<T>::value && std::extent<T>::value == 0,
913 std::unique_ptr<T>>::type
914make_unique(size_t n) {
915 return std::unique_ptr<T>(new typename std::remove_extent<T>::type[n]());
916}
917
918/// This function isn't used and is only here to provide better compile errors.
919template <class T, class... Args>
920typename std::enable_if<std::extent<T>::value != 0>::type
921make_unique(Args &&...) = delete;
922
923struct FreeDeleter {
924 void operator()(void* v) {
925 ::free(v);
926 }
927};
928
929template<typename First, typename Second>
930struct pair_hash {
931 size_t operator()(const std::pair<First, Second> &P) const {
932 return std::hash<First>()(P.first) * 31 + std::hash<Second>()(P.second);
933 }
934};
935
936/// A functor like C++14's std::less<void> in its absence.
937struct less {
938 template <typename A, typename B> bool operator()(A &&a, B &&b) const {
939 return std::forward<A>(a) < std::forward<B>(b);
940 }
941};
942
943/// A functor like C++14's std::equal<void> in its absence.
944struct equal {
945 template <typename A, typename B> bool operator()(A &&a, B &&b) const {
946 return std::forward<A>(a) == std::forward<B>(b);
947 }
948};
949
950/// Binary functor that adapts to any other binary functor after dereferencing
951/// operands.
952template <typename T> struct deref {
953 T func;
954
955 // Could be further improved to cope with non-derivable functors and
956 // non-binary functors (should be a variadic template member function
957 // operator()).
958 template <typename A, typename B>
959 auto operator()(A &lhs, B &rhs) const -> decltype(func(*lhs, *rhs)) {
960 assert(lhs)(static_cast <bool> (lhs) ? void (0) : __assert_fail ("lhs"
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/ADT/STLExtras.h"
, 960, __extension__ __PRETTY_FUNCTION__))
;
961 assert(rhs)(static_cast <bool> (rhs) ? void (0) : __assert_fail ("rhs"
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/ADT/STLExtras.h"
, 961, __extension__ __PRETTY_FUNCTION__))
;
962 return func(*lhs, *rhs);
963 }
964};
965
966namespace detail {
967
968template <typename R> class enumerator_iter;
969
970template <typename R> struct result_pair {
971 friend class enumerator_iter<R>;
972
973 result_pair() = default;
974 result_pair(std::size_t Index, IterOfRange<R> Iter)
975 : Index(Index), Iter(Iter) {}
976
977 result_pair<R> &operator=(const result_pair<R> &Other) {
978 Index = Other.Index;
979 Iter = Other.Iter;
980 return *this;
981 }
982
983 std::size_t index() const { return Index; }
984 const ValueOfRange<R> &value() const { return *Iter; }
985 ValueOfRange<R> &value() { return *Iter; }
986
987private:
988 std::size_t Index = std::numeric_limits<std::size_t>::max();
989 IterOfRange<R> Iter;
990};
991
992template <typename R>
993class enumerator_iter
994 : public iterator_facade_base<
995 enumerator_iter<R>, std::forward_iterator_tag, result_pair<R>,
996 typename std::iterator_traits<IterOfRange<R>>::difference_type,
997 typename std::iterator_traits<IterOfRange<R>>::pointer,
998 typename std::iterator_traits<IterOfRange<R>>::reference> {
999 using result_type = result_pair<R>;
1000
1001public:
1002 explicit enumerator_iter(IterOfRange<R> EndIter)
1003 : Result(std::numeric_limits<size_t>::max(), EndIter) {}
1004
1005 enumerator_iter(std::size_t Index, IterOfRange<R> Iter)
1006 : Result(Index, Iter) {}
1007
1008 result_type &operator*() { return Result; }
1009 const result_type &operator*() const { return Result; }
1010
1011 enumerator_iter<R> &operator++() {
1012 assert(Result.Index != std::numeric_limits<size_t>::max())(static_cast <bool> (Result.Index != std::numeric_limits
<size_t>::max()) ? void (0) : __assert_fail ("Result.Index != std::numeric_limits<size_t>::max()"
, "/build/llvm-toolchain-snapshot-6.0~svn318693/include/llvm/ADT/STLExtras.h"
, 1012, __extension__ __PRETTY_FUNCTION__))
;
1013 ++Result.Iter;
1014 ++Result.Index;
1015 return *this;
1016 }
1017
1018 bool operator==(const enumerator_iter<R> &RHS) const {
1019 // Don't compare indices here, only iterators. It's possible for an end
1020 // iterator to have different indices depending on whether it was created
1021 // by calling std::end() versus incrementing a valid iterator.
1022 return Result.Iter == RHS.Result.Iter;
1023 }
1024
1025 enumerator_iter<R> &operator=(const enumerator_iter<R> &Other) {
1026 Result = Other.Result;
1027 return *this;
1028 }
1029
1030private:
1031 result_type Result;
1032};
1033
1034template <typename R> class enumerator {
1035public:
1036 explicit enumerator(R &&Range) : TheRange(std::forward<R>(Range)) {}
1037
1038 enumerator_iter<R> begin() {
1039 return enumerator_iter<R>(0, std::begin(TheRange));
1040 }
1041
1042 enumerator_iter<R> end() {
1043 return enumerator_iter<R>(std::end(TheRange));
1044 }
1045
1046private:
1047 R TheRange;
1048};
1049
1050} // end namespace detail
1051
1052/// Given an input range, returns a new range whose values are are pair (A,B)
1053/// such that A is the 0-based index of the item in the sequence, and B is
1054/// the value from the original sequence. Example:
1055///
1056/// std::vector<char> Items = {'A', 'B', 'C', 'D'};
1057/// for (auto X : enumerate(Items)) {
1058/// printf("Item %d - %c\n", X.index(), X.value());
1059/// }
1060///
1061/// Output:
1062/// Item 0 - A
1063/// Item 1 - B
1064/// Item 2 - C
1065/// Item 3 - D
1066///
1067template <typename R> detail::enumerator<R> enumerate(R &&TheRange) {
1068 return detail::enumerator<R>(std::forward<R>(TheRange));
1069}
1070
1071namespace detail {
1072
1073template <typename F, typename Tuple, std::size_t... I>
1074auto apply_tuple_impl(F &&f, Tuple &&t, index_sequence<I...>)
1075 -> decltype(std::forward<F>(f)(std::get<I>(std::forward<Tuple>(t))...)) {
1076 return std::forward<F>(f)(std::get<I>(std::forward<Tuple>(t))...);
1077}
1078
1079} // end namespace detail
1080
1081/// Given an input tuple (a1, a2, ..., an), pass the arguments of the
1082/// tuple variadically to f as if by calling f(a1, a2, ..., an) and
1083/// return the result.
1084template <typename F, typename Tuple>
1085auto apply_tuple(F &&f, Tuple &&t) -> decltype(detail::apply_tuple_impl(
1086 std::forward<F>(f), std::forward<Tuple>(t),
1087 build_index_impl<
1088 std::tuple_size<typename std::decay<Tuple>::type>::value>{})) {
1089 using Indices = build_index_impl<
1090 std::tuple_size<typename std::decay<Tuple>::type>::value>;
1091
1092 return detail::apply_tuple_impl(std::forward<F>(f), std::forward<Tuple>(t),
1093 Indices{});
1094}
1095
1096} // end namespace llvm
1097
1098#endif // LLVM_ADT_STLEXTRAS_H