Bug Summary

File:clang/lib/CodeGen/CGCoroutine.cpp
Warning:line 95, column 21
Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name CGCoroutine.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -relaxed-aliasing -fmath-errno -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/build-llvm/tools/clang/lib/CodeGen -resource-dir /usr/lib/llvm-13/lib/clang/13.0.0 -D CLANG_ROUND_TRIP_CC1_ARGS=ON -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/build-llvm/tools/clang/lib/CodeGen -I /build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen -I /build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/include -I /build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/build-llvm/tools/clang/include -I /build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/build-llvm/include -I /build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/llvm/include -D NDEBUG -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/backward -internal-isystem /usr/lib/llvm-13/lib/clang/13.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/build-llvm/tools/clang/lib/CodeGen -fdebug-prefix-map=/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82=. -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2021-06-21-164211-33944-1 -x c++ /build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp

/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp

1//===----- CGCoroutine.cpp - Emit LLVM Code for C++ coroutines ------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This contains code dealing with C++ code generation of coroutines.
10//
11//===----------------------------------------------------------------------===//
12
13#include "CGCleanup.h"
14#include "CodeGenFunction.h"
15#include "llvm/ADT/ScopeExit.h"
16#include "clang/AST/StmtCXX.h"
17#include "clang/AST/StmtVisitor.h"
18
19using namespace clang;
20using namespace CodeGen;
21
22using llvm::Value;
23using llvm::BasicBlock;
24
25namespace {
26enum class AwaitKind { Init, Normal, Yield, Final };
27static constexpr llvm::StringLiteral AwaitKindStr[] = {"init", "await", "yield",
28 "final"};
29}
30
31struct clang::CodeGen::CGCoroData {
32 // What is the current await expression kind and how many
33 // await/yield expressions were encountered so far.
34 // These are used to generate pretty labels for await expressions in LLVM IR.
35 AwaitKind CurrentAwaitKind = AwaitKind::Init;
36 unsigned AwaitNum = 0;
37 unsigned YieldNum = 0;
38
39 // How many co_return statements are in the coroutine. Used to decide whether
40 // we need to add co_return; equivalent at the end of the user authored body.
41 unsigned CoreturnCount = 0;
42
43 // A branch to this block is emitted when coroutine needs to suspend.
44 llvm::BasicBlock *SuspendBB = nullptr;
45
46 // The promise type's 'unhandled_exception' handler, if it defines one.
47 Stmt *ExceptionHandler = nullptr;
48
49 // A temporary i1 alloca that stores whether 'await_resume' threw an
50 // exception. If it did, 'true' is stored in this variable, and the coroutine
51 // body must be skipped. If the promise type does not define an exception
52 // handler, this is null.
53 llvm::Value *ResumeEHVar = nullptr;
54
55 // Stores the jump destination just before the coroutine memory is freed.
56 // This is the destination that every suspend point jumps to for the cleanup
57 // branch.
58 CodeGenFunction::JumpDest CleanupJD;
59
60 // Stores the jump destination just before the final suspend. The co_return
61 // statements jumps to this point after calling return_xxx promise member.
62 CodeGenFunction::JumpDest FinalJD;
63
64 // Stores the llvm.coro.id emitted in the function so that we can supply it
65 // as the first argument to coro.begin, coro.alloc and coro.free intrinsics.
66 // Note: llvm.coro.id returns a token that cannot be directly expressed in a
67 // builtin.
68 llvm::CallInst *CoroId = nullptr;
69
70 // Stores the llvm.coro.begin emitted in the function so that we can replace
71 // all coro.frame intrinsics with direct SSA value of coro.begin that returns
72 // the address of the coroutine frame of the current coroutine.
73 llvm::CallInst *CoroBegin = nullptr;
74
75 // Stores the last emitted coro.free for the deallocate expressions, we use it
76 // to wrap dealloc code with if(auto mem = coro.free) dealloc(mem).
77 llvm::CallInst *LastCoroFree = nullptr;
78
79 // If coro.id came from the builtin, remember the expression to give better
80 // diagnostic. If CoroIdExpr is nullptr, the coro.id was created by
81 // EmitCoroutineBody.
82 CallExpr const *CoroIdExpr = nullptr;
83};
84
85// Defining these here allows to keep CGCoroData private to this file.
86clang::CodeGen::CodeGenFunction::CGCoroInfo::CGCoroInfo() {}
87CodeGenFunction::CGCoroInfo::~CGCoroInfo() {}
88
89static void createCoroData(CodeGenFunction &CGF,
90 CodeGenFunction::CGCoroInfo &CurCoro,
91 llvm::CallInst *CoroId,
92 CallExpr const *CoroIdExpr = nullptr) {
93 if (CurCoro.Data) {
3
Calling 'unique_ptr::operator bool'
7
Returning from 'unique_ptr::operator bool'
8
Taking true branch
94 if (CurCoro.Data->CoroIdExpr)
9
Assuming field 'CoroIdExpr' is non-null
10
Taking true branch
95 CGF.CGM.Error(CoroIdExpr->getBeginLoc(),
11
Called C++ object pointer is null
96 "only one __builtin_coro_id can be used in a function");
97 else if (CoroIdExpr)
98 CGF.CGM.Error(CoroIdExpr->getBeginLoc(),
99 "__builtin_coro_id shall not be used in a C++ coroutine");
100 else
101 llvm_unreachable("EmitCoroutineBodyStatement called twice?")::llvm::llvm_unreachable_internal("EmitCoroutineBodyStatement called twice?"
, "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 101)
;
102
103 return;
104 }
105
106 CurCoro.Data = std::unique_ptr<CGCoroData>(new CGCoroData);
107 CurCoro.Data->CoroId = CoroId;
108 CurCoro.Data->CoroIdExpr = CoroIdExpr;
109}
110
111// Synthesize a pretty name for a suspend point.
112static SmallString<32> buildSuspendPrefixStr(CGCoroData &Coro, AwaitKind Kind) {
113 unsigned No = 0;
114 switch (Kind) {
115 case AwaitKind::Init:
116 case AwaitKind::Final:
117 break;
118 case AwaitKind::Normal:
119 No = ++Coro.AwaitNum;
120 break;
121 case AwaitKind::Yield:
122 No = ++Coro.YieldNum;
123 break;
124 }
125 SmallString<32> Prefix(AwaitKindStr[static_cast<unsigned>(Kind)]);
126 if (No > 1) {
127 Twine(No).toVector(Prefix);
128 }
129 return Prefix;
130}
131
132static bool memberCallExpressionCanThrow(const Expr *E) {
133 if (const auto *CE = dyn_cast<CXXMemberCallExpr>(E))
134 if (const auto *Proto =
135 CE->getMethodDecl()->getType()->getAs<FunctionProtoType>())
136 if (isNoexceptExceptionSpec(Proto->getExceptionSpecType()) &&
137 Proto->canThrow() == CT_Cannot)
138 return false;
139 return true;
140}
141
142// Emit suspend expression which roughly looks like:
143//
144// auto && x = CommonExpr();
145// if (!x.await_ready()) {
146// llvm_coro_save();
147// x.await_suspend(...); (*)
148// llvm_coro_suspend(); (**)
149// }
150// x.await_resume();
151//
152// where the result of the entire expression is the result of x.await_resume()
153//
154// (*) If x.await_suspend return type is bool, it allows to veto a suspend:
155// if (x.await_suspend(...))
156// llvm_coro_suspend();
157//
158// (**) llvm_coro_suspend() encodes three possible continuations as
159// a switch instruction:
160//
161// %where-to = call i8 @llvm.coro.suspend(...)
162// switch i8 %where-to, label %coro.ret [ ; jump to epilogue to suspend
163// i8 0, label %yield.ready ; go here when resumed
164// i8 1, label %yield.cleanup ; go here when destroyed
165// ]
166//
167// See llvm's docs/Coroutines.rst for more details.
168//
169namespace {
170 struct LValueOrRValue {
171 LValue LV;
172 RValue RV;
173 };
174}
175static LValueOrRValue emitSuspendExpression(CodeGenFunction &CGF, CGCoroData &Coro,
176 CoroutineSuspendExpr const &S,
177 AwaitKind Kind, AggValueSlot aggSlot,
178 bool ignoreResult, bool forLValue) {
179 auto *E = S.getCommonExpr();
180
181 auto Binder =
182 CodeGenFunction::OpaqueValueMappingData::bind(CGF, S.getOpaqueValue(), E);
183 auto UnbindOnExit = llvm::make_scope_exit([&] { Binder.unbind(CGF); });
184
185 auto Prefix = buildSuspendPrefixStr(Coro, Kind);
186 BasicBlock *ReadyBlock = CGF.createBasicBlock(Prefix + Twine(".ready"));
187 BasicBlock *SuspendBlock = CGF.createBasicBlock(Prefix + Twine(".suspend"));
188 BasicBlock *CleanupBlock = CGF.createBasicBlock(Prefix + Twine(".cleanup"));
189
190 // If expression is ready, no need to suspend.
191 CGF.EmitBranchOnBoolExpr(S.getReadyExpr(), ReadyBlock, SuspendBlock, 0);
192
193 // Otherwise, emit suspend logic.
194 CGF.EmitBlock(SuspendBlock);
195
196 auto &Builder = CGF.Builder;
197 llvm::Function *CoroSave = CGF.CGM.getIntrinsic(llvm::Intrinsic::coro_save);
198 auto *NullPtr = llvm::ConstantPointerNull::get(CGF.CGM.Int8PtrTy);
199 auto *SaveCall = Builder.CreateCall(CoroSave, {NullPtr});
200
201 auto *SuspendRet = CGF.EmitScalarExpr(S.getSuspendExpr());
202 if (SuspendRet != nullptr && SuspendRet->getType()->isIntegerTy(1)) {
203 // Veto suspension if requested by bool returning await_suspend.
204 BasicBlock *RealSuspendBlock =
205 CGF.createBasicBlock(Prefix + Twine(".suspend.bool"));
206 CGF.Builder.CreateCondBr(SuspendRet, RealSuspendBlock, ReadyBlock);
207 CGF.EmitBlock(RealSuspendBlock);
208 }
209
210 // Emit the suspend point.
211 const bool IsFinalSuspend = (Kind == AwaitKind::Final);
212 llvm::Function *CoroSuspend =
213 CGF.CGM.getIntrinsic(llvm::Intrinsic::coro_suspend);
214 auto *SuspendResult = Builder.CreateCall(
215 CoroSuspend, {SaveCall, Builder.getInt1(IsFinalSuspend)});
216
217 // Create a switch capturing three possible continuations.
218 auto *Switch = Builder.CreateSwitch(SuspendResult, Coro.SuspendBB, 2);
219 Switch->addCase(Builder.getInt8(0), ReadyBlock);
220 Switch->addCase(Builder.getInt8(1), CleanupBlock);
221
222 // Emit cleanup for this suspend point.
223 CGF.EmitBlock(CleanupBlock);
224 CGF.EmitBranchThroughCleanup(Coro.CleanupJD);
225
226 // Emit await_resume expression.
227 CGF.EmitBlock(ReadyBlock);
228
229 // Exception handling requires additional IR. If the 'await_resume' function
230 // is marked as 'noexcept', we avoid generating this additional IR.
231 CXXTryStmt *TryStmt = nullptr;
232 if (Coro.ExceptionHandler && Kind == AwaitKind::Init &&
233 memberCallExpressionCanThrow(S.getResumeExpr())) {
234 Coro.ResumeEHVar =
235 CGF.CreateTempAlloca(Builder.getInt1Ty(), Prefix + Twine("resume.eh"));
236 Builder.CreateFlagStore(true, Coro.ResumeEHVar);
237
238 auto Loc = S.getResumeExpr()->getExprLoc();
239 auto *Catch = new (CGF.getContext())
240 CXXCatchStmt(Loc, /*exDecl=*/nullptr, Coro.ExceptionHandler);
241 auto *TryBody =
242 CompoundStmt::Create(CGF.getContext(), S.getResumeExpr(), Loc, Loc);
243 TryStmt = CXXTryStmt::Create(CGF.getContext(), Loc, TryBody, Catch);
244 CGF.EnterCXXTryStmt(*TryStmt);
245 }
246
247 LValueOrRValue Res;
248 if (forLValue)
249 Res.LV = CGF.EmitLValue(S.getResumeExpr());
250 else
251 Res.RV = CGF.EmitAnyExpr(S.getResumeExpr(), aggSlot, ignoreResult);
252
253 if (TryStmt) {
254 Builder.CreateFlagStore(false, Coro.ResumeEHVar);
255 CGF.ExitCXXTryStmt(*TryStmt);
256 }
257
258 return Res;
259}
260
261RValue CodeGenFunction::EmitCoawaitExpr(const CoawaitExpr &E,
262 AggValueSlot aggSlot,
263 bool ignoreResult) {
264 return emitSuspendExpression(*this, *CurCoro.Data, E,
265 CurCoro.Data->CurrentAwaitKind, aggSlot,
266 ignoreResult, /*forLValue*/false).RV;
267}
268RValue CodeGenFunction::EmitCoyieldExpr(const CoyieldExpr &E,
269 AggValueSlot aggSlot,
270 bool ignoreResult) {
271 return emitSuspendExpression(*this, *CurCoro.Data, E, AwaitKind::Yield,
272 aggSlot, ignoreResult, /*forLValue*/false).RV;
273}
274
275void CodeGenFunction::EmitCoreturnStmt(CoreturnStmt const &S) {
276 ++CurCoro.Data->CoreturnCount;
277 const Expr *RV = S.getOperand();
278 if (RV && RV->getType()->isVoidType() && !isa<InitListExpr>(RV)) {
279 // Make sure to evaluate the non initlist expression of a co_return
280 // with a void expression for side effects.
281 RunCleanupsScope cleanupScope(*this);
282 EmitIgnoredExpr(RV);
283 }
284 EmitStmt(S.getPromiseCall());
285 EmitBranchThroughCleanup(CurCoro.Data->FinalJD);
286}
287
288
289#ifndef NDEBUG
290static QualType getCoroutineSuspendExprReturnType(const ASTContext &Ctx,
291 const CoroutineSuspendExpr *E) {
292 const auto *RE = E->getResumeExpr();
293 // Is it possible for RE to be a CXXBindTemporaryExpr wrapping
294 // a MemberCallExpr?
295 assert(isa<CallExpr>(RE) && "unexpected suspend expression type")(static_cast <bool> (isa<CallExpr>(RE) &&
"unexpected suspend expression type") ? void (0) : __assert_fail
("isa<CallExpr>(RE) && \"unexpected suspend expression type\""
, "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 295, __extension__ __PRETTY_FUNCTION__))
;
296 return cast<CallExpr>(RE)->getCallReturnType(Ctx);
297}
298#endif
299
300LValue
301CodeGenFunction::EmitCoawaitLValue(const CoawaitExpr *E) {
302 assert(getCoroutineSuspendExprReturnType(getContext(), E)->isReferenceType() &&(static_cast <bool> (getCoroutineSuspendExprReturnType(
getContext(), E)->isReferenceType() && "Can't have a scalar return unless the return type is a "
"reference type!") ? void (0) : __assert_fail ("getCoroutineSuspendExprReturnType(getContext(), E)->isReferenceType() && \"Can't have a scalar return unless the return type is a \" \"reference type!\""
, "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 304, __extension__ __PRETTY_FUNCTION__))
303 "Can't have a scalar return unless the return type is a "(static_cast <bool> (getCoroutineSuspendExprReturnType(
getContext(), E)->isReferenceType() && "Can't have a scalar return unless the return type is a "
"reference type!") ? void (0) : __assert_fail ("getCoroutineSuspendExprReturnType(getContext(), E)->isReferenceType() && \"Can't have a scalar return unless the return type is a \" \"reference type!\""
, "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 304, __extension__ __PRETTY_FUNCTION__))
304 "reference type!")(static_cast <bool> (getCoroutineSuspendExprReturnType(
getContext(), E)->isReferenceType() && "Can't have a scalar return unless the return type is a "
"reference type!") ? void (0) : __assert_fail ("getCoroutineSuspendExprReturnType(getContext(), E)->isReferenceType() && \"Can't have a scalar return unless the return type is a \" \"reference type!\""
, "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 304, __extension__ __PRETTY_FUNCTION__))
;
305 return emitSuspendExpression(*this, *CurCoro.Data, *E,
306 CurCoro.Data->CurrentAwaitKind, AggValueSlot::ignored(),
307 /*ignoreResult*/false, /*forLValue*/true).LV;
308}
309
310LValue
311CodeGenFunction::EmitCoyieldLValue(const CoyieldExpr *E) {
312 assert(getCoroutineSuspendExprReturnType(getContext(), E)->isReferenceType() &&(static_cast <bool> (getCoroutineSuspendExprReturnType(
getContext(), E)->isReferenceType() && "Can't have a scalar return unless the return type is a "
"reference type!") ? void (0) : __assert_fail ("getCoroutineSuspendExprReturnType(getContext(), E)->isReferenceType() && \"Can't have a scalar return unless the return type is a \" \"reference type!\""
, "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 314, __extension__ __PRETTY_FUNCTION__))
313 "Can't have a scalar return unless the return type is a "(static_cast <bool> (getCoroutineSuspendExprReturnType(
getContext(), E)->isReferenceType() && "Can't have a scalar return unless the return type is a "
"reference type!") ? void (0) : __assert_fail ("getCoroutineSuspendExprReturnType(getContext(), E)->isReferenceType() && \"Can't have a scalar return unless the return type is a \" \"reference type!\""
, "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 314, __extension__ __PRETTY_FUNCTION__))
314 "reference type!")(static_cast <bool> (getCoroutineSuspendExprReturnType(
getContext(), E)->isReferenceType() && "Can't have a scalar return unless the return type is a "
"reference type!") ? void (0) : __assert_fail ("getCoroutineSuspendExprReturnType(getContext(), E)->isReferenceType() && \"Can't have a scalar return unless the return type is a \" \"reference type!\""
, "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 314, __extension__ __PRETTY_FUNCTION__))
;
315 return emitSuspendExpression(*this, *CurCoro.Data, *E,
316 AwaitKind::Yield, AggValueSlot::ignored(),
317 /*ignoreResult*/false, /*forLValue*/true).LV;
318}
319
320// Hunts for the parameter reference in the parameter copy/move declaration.
321namespace {
322struct GetParamRef : public StmtVisitor<GetParamRef> {
323public:
324 DeclRefExpr *Expr = nullptr;
325 GetParamRef() {}
326 void VisitDeclRefExpr(DeclRefExpr *E) {
327 assert(Expr == nullptr && "multilple declref in param move")(static_cast <bool> (Expr == nullptr && "multilple declref in param move"
) ? void (0) : __assert_fail ("Expr == nullptr && \"multilple declref in param move\""
, "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 327, __extension__ __PRETTY_FUNCTION__))
;
328 Expr = E;
329 }
330 void VisitStmt(Stmt *S) {
331 for (auto *C : S->children()) {
332 if (C)
333 Visit(C);
334 }
335 }
336};
337}
338
339// This class replaces references to parameters to their copies by changing
340// the addresses in CGF.LocalDeclMap and restoring back the original values in
341// its destructor.
342
343namespace {
344 struct ParamReferenceReplacerRAII {
345 CodeGenFunction::DeclMapTy SavedLocals;
346 CodeGenFunction::DeclMapTy& LocalDeclMap;
347
348 ParamReferenceReplacerRAII(CodeGenFunction::DeclMapTy &LocalDeclMap)
349 : LocalDeclMap(LocalDeclMap) {}
350
351 void addCopy(DeclStmt const *PM) {
352 // Figure out what param it refers to.
353
354 assert(PM->isSingleDecl())(static_cast <bool> (PM->isSingleDecl()) ? void (0) :
__assert_fail ("PM->isSingleDecl()", "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 354, __extension__ __PRETTY_FUNCTION__))
;
355 VarDecl const*VD = static_cast<VarDecl const*>(PM->getSingleDecl());
356 Expr const *InitExpr = VD->getInit();
357 GetParamRef Visitor;
358 Visitor.Visit(const_cast<Expr*>(InitExpr));
359 assert(Visitor.Expr)(static_cast <bool> (Visitor.Expr) ? void (0) : __assert_fail
("Visitor.Expr", "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 359, __extension__ __PRETTY_FUNCTION__))
;
360 DeclRefExpr *DREOrig = Visitor.Expr;
361 auto *PD = DREOrig->getDecl();
362
363 auto it = LocalDeclMap.find(PD);
364 assert(it != LocalDeclMap.end() && "parameter is not found")(static_cast <bool> (it != LocalDeclMap.end() &&
"parameter is not found") ? void (0) : __assert_fail ("it != LocalDeclMap.end() && \"parameter is not found\""
, "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 364, __extension__ __PRETTY_FUNCTION__))
;
365 SavedLocals.insert({ PD, it->second });
366
367 auto copyIt = LocalDeclMap.find(VD);
368 assert(copyIt != LocalDeclMap.end() && "parameter copy is not found")(static_cast <bool> (copyIt != LocalDeclMap.end() &&
"parameter copy is not found") ? void (0) : __assert_fail ("copyIt != LocalDeclMap.end() && \"parameter copy is not found\""
, "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 368, __extension__ __PRETTY_FUNCTION__))
;
369 it->second = copyIt->getSecond();
370 }
371
372 ~ParamReferenceReplacerRAII() {
373 for (auto&& SavedLocal : SavedLocals) {
374 LocalDeclMap.insert({SavedLocal.first, SavedLocal.second});
375 }
376 }
377 };
378}
379
380// For WinEH exception representation backend needs to know what funclet coro.end
381// belongs to. That information is passed in a funclet bundle.
382static SmallVector<llvm::OperandBundleDef, 1>
383getBundlesForCoroEnd(CodeGenFunction &CGF) {
384 SmallVector<llvm::OperandBundleDef, 1> BundleList;
385
386 if (llvm::Instruction *EHPad = CGF.CurrentFuncletPad)
387 BundleList.emplace_back("funclet", EHPad);
388
389 return BundleList;
390}
391
392namespace {
393// We will insert coro.end to cut any of the destructors for objects that
394// do not need to be destroyed once the coroutine is resumed.
395// See llvm/docs/Coroutines.rst for more details about coro.end.
396struct CallCoroEnd final : public EHScopeStack::Cleanup {
397 void Emit(CodeGenFunction &CGF, Flags flags) override {
398 auto &CGM = CGF.CGM;
399 auto *NullPtr = llvm::ConstantPointerNull::get(CGF.Int8PtrTy);
400 llvm::Function *CoroEndFn = CGM.getIntrinsic(llvm::Intrinsic::coro_end);
401 // See if we have a funclet bundle to associate coro.end with. (WinEH)
402 auto Bundles = getBundlesForCoroEnd(CGF);
403 auto *CoroEnd = CGF.Builder.CreateCall(
404 CoroEndFn, {NullPtr, CGF.Builder.getTrue()}, Bundles);
405 if (Bundles.empty()) {
406 // Otherwise, (landingpad model), create a conditional branch that leads
407 // either to a cleanup block or a block with EH resume instruction.
408 auto *ResumeBB = CGF.getEHResumeBlock(/*isCleanup=*/true);
409 auto *CleanupContBB = CGF.createBasicBlock("cleanup.cont");
410 CGF.Builder.CreateCondBr(CoroEnd, ResumeBB, CleanupContBB);
411 CGF.EmitBlock(CleanupContBB);
412 }
413 }
414};
415}
416
417namespace {
418// Make sure to call coro.delete on scope exit.
419struct CallCoroDelete final : public EHScopeStack::Cleanup {
420 Stmt *Deallocate;
421
422 // Emit "if (coro.free(CoroId, CoroBegin)) Deallocate;"
423
424 // Note: That deallocation will be emitted twice: once for a normal exit and
425 // once for exceptional exit. This usage is safe because Deallocate does not
426 // contain any declarations. The SubStmtBuilder::makeNewAndDeleteExpr()
427 // builds a single call to a deallocation function which is safe to emit
428 // multiple times.
429 void Emit(CodeGenFunction &CGF, Flags) override {
430 // Remember the current point, as we are going to emit deallocation code
431 // first to get to coro.free instruction that is an argument to a delete
432 // call.
433 BasicBlock *SaveInsertBlock = CGF.Builder.GetInsertBlock();
434
435 auto *FreeBB = CGF.createBasicBlock("coro.free");
436 CGF.EmitBlock(FreeBB);
437 CGF.EmitStmt(Deallocate);
438
439 auto *AfterFreeBB = CGF.createBasicBlock("after.coro.free");
440 CGF.EmitBlock(AfterFreeBB);
441
442 // We should have captured coro.free from the emission of deallocate.
443 auto *CoroFree = CGF.CurCoro.Data->LastCoroFree;
444 if (!CoroFree) {
445 CGF.CGM.Error(Deallocate->getBeginLoc(),
446 "Deallocation expressoin does not refer to coro.free");
447 return;
448 }
449
450 // Get back to the block we were originally and move coro.free there.
451 auto *InsertPt = SaveInsertBlock->getTerminator();
452 CoroFree->moveBefore(InsertPt);
453 CGF.Builder.SetInsertPoint(InsertPt);
454
455 // Add if (auto *mem = coro.free) Deallocate;
456 auto *NullPtr = llvm::ConstantPointerNull::get(CGF.Int8PtrTy);
457 auto *Cond = CGF.Builder.CreateICmpNE(CoroFree, NullPtr);
458 CGF.Builder.CreateCondBr(Cond, FreeBB, AfterFreeBB);
459
460 // No longer need old terminator.
461 InsertPt->eraseFromParent();
462 CGF.Builder.SetInsertPoint(AfterFreeBB);
463 }
464 explicit CallCoroDelete(Stmt *DeallocStmt) : Deallocate(DeallocStmt) {}
465};
466}
467
468namespace {
469struct GetReturnObjectManager {
470 CodeGenFunction &CGF;
471 CGBuilderTy &Builder;
472 const CoroutineBodyStmt &S;
473
474 Address GroActiveFlag;
475 CodeGenFunction::AutoVarEmission GroEmission;
476
477 GetReturnObjectManager(CodeGenFunction &CGF, const CoroutineBodyStmt &S)
478 : CGF(CGF), Builder(CGF.Builder), S(S), GroActiveFlag(Address::invalid()),
479 GroEmission(CodeGenFunction::AutoVarEmission::invalid()) {}
480
481 // The gro variable has to outlive coroutine frame and coroutine promise, but,
482 // it can only be initialized after coroutine promise was created, thus, we
483 // split its emission in two parts. EmitGroAlloca emits an alloca and sets up
484 // cleanups. Later when coroutine promise is available we initialize the gro
485 // and sets the flag that the cleanup is now active.
486
487 void EmitGroAlloca() {
488 auto *GroDeclStmt = dyn_cast<DeclStmt>(S.getResultDecl());
489 if (!GroDeclStmt) {
490 // If get_return_object returns void, no need to do an alloca.
491 return;
492 }
493
494 auto *GroVarDecl = cast<VarDecl>(GroDeclStmt->getSingleDecl());
495
496 // Set GRO flag that it is not initialized yet
497 GroActiveFlag =
498 CGF.CreateTempAlloca(Builder.getInt1Ty(), CharUnits::One(), "gro.active");
499 Builder.CreateStore(Builder.getFalse(), GroActiveFlag);
500
501 GroEmission = CGF.EmitAutoVarAlloca(*GroVarDecl);
502
503 // Remember the top of EHStack before emitting the cleanup.
504 auto old_top = CGF.EHStack.stable_begin();
505 CGF.EmitAutoVarCleanups(GroEmission);
506 auto top = CGF.EHStack.stable_begin();
507
508 // Make the cleanup conditional on gro.active
509 for (auto b = CGF.EHStack.find(top), e = CGF.EHStack.find(old_top);
510 b != e; b++) {
511 if (auto *Cleanup = dyn_cast<EHCleanupScope>(&*b)) {
512 assert(!Cleanup->hasActiveFlag() && "cleanup already has active flag?")(static_cast <bool> (!Cleanup->hasActiveFlag() &&
"cleanup already has active flag?") ? void (0) : __assert_fail
("!Cleanup->hasActiveFlag() && \"cleanup already has active flag?\""
, "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 512, __extension__ __PRETTY_FUNCTION__))
;
513 Cleanup->setActiveFlag(GroActiveFlag);
514 Cleanup->setTestFlagInEHCleanup();
515 Cleanup->setTestFlagInNormalCleanup();
516 }
517 }
518 }
519
520 void EmitGroInit() {
521 if (!GroActiveFlag.isValid()) {
522 // No Gro variable was allocated. Simply emit the call to
523 // get_return_object.
524 CGF.EmitStmt(S.getResultDecl());
525 return;
526 }
527
528 CGF.EmitAutoVarInit(GroEmission);
529 Builder.CreateStore(Builder.getTrue(), GroActiveFlag);
530 }
531};
532}
533
534static void emitBodyAndFallthrough(CodeGenFunction &CGF,
535 const CoroutineBodyStmt &S, Stmt *Body) {
536 CGF.EmitStmt(Body);
537 const bool CanFallthrough = CGF.Builder.GetInsertBlock();
538 if (CanFallthrough)
539 if (Stmt *OnFallthrough = S.getFallthroughHandler())
540 CGF.EmitStmt(OnFallthrough);
541}
542
543void CodeGenFunction::EmitCoroutineBody(const CoroutineBodyStmt &S) {
544 auto *NullPtr = llvm::ConstantPointerNull::get(Builder.getInt8PtrTy());
545 auto &TI = CGM.getContext().getTargetInfo();
546 unsigned NewAlign = TI.getNewAlign() / TI.getCharWidth();
547
548 auto *EntryBB = Builder.GetInsertBlock();
549 auto *AllocBB = createBasicBlock("coro.alloc");
550 auto *InitBB = createBasicBlock("coro.init");
551 auto *FinalBB = createBasicBlock("coro.final");
552 auto *RetBB = createBasicBlock("coro.ret");
553
554 auto *CoroId = Builder.CreateCall(
555 CGM.getIntrinsic(llvm::Intrinsic::coro_id),
556 {Builder.getInt32(NewAlign), NullPtr, NullPtr, NullPtr});
557 createCoroData(*this, CurCoro, CoroId);
1
Passing null pointer value via 4th parameter 'CoroIdExpr'
2
Calling 'createCoroData'
558 CurCoro.Data->SuspendBB = RetBB;
559 assert(ShouldEmitLifetimeMarkers &&(static_cast <bool> (ShouldEmitLifetimeMarkers &&
"Must emit lifetime intrinsics for coroutines") ? void (0) :
__assert_fail ("ShouldEmitLifetimeMarkers && \"Must emit lifetime intrinsics for coroutines\""
, "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 560, __extension__ __PRETTY_FUNCTION__))
560 "Must emit lifetime intrinsics for coroutines")(static_cast <bool> (ShouldEmitLifetimeMarkers &&
"Must emit lifetime intrinsics for coroutines") ? void (0) :
__assert_fail ("ShouldEmitLifetimeMarkers && \"Must emit lifetime intrinsics for coroutines\""
, "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 560, __extension__ __PRETTY_FUNCTION__))
;
561
562 // Backend is allowed to elide memory allocations, to help it, emit
563 // auto mem = coro.alloc() ? 0 : ... allocation code ...;
564 auto *CoroAlloc = Builder.CreateCall(
565 CGM.getIntrinsic(llvm::Intrinsic::coro_alloc), {CoroId});
566
567 Builder.CreateCondBr(CoroAlloc, AllocBB, InitBB);
568
569 EmitBlock(AllocBB);
570 auto *AllocateCall = EmitScalarExpr(S.getAllocate());
571 auto *AllocOrInvokeContBB = Builder.GetInsertBlock();
572
573 // Handle allocation failure if 'ReturnStmtOnAllocFailure' was provided.
574 if (auto *RetOnAllocFailure = S.getReturnStmtOnAllocFailure()) {
575 auto *RetOnFailureBB = createBasicBlock("coro.ret.on.failure");
576
577 // See if allocation was successful.
578 auto *NullPtr = llvm::ConstantPointerNull::get(Int8PtrTy);
579 auto *Cond = Builder.CreateICmpNE(AllocateCall, NullPtr);
580 Builder.CreateCondBr(Cond, InitBB, RetOnFailureBB);
581
582 // If not, return OnAllocFailure object.
583 EmitBlock(RetOnFailureBB);
584 EmitStmt(RetOnAllocFailure);
585 }
586 else {
587 Builder.CreateBr(InitBB);
588 }
589
590 EmitBlock(InitBB);
591
592 // Pass the result of the allocation to coro.begin.
593 auto *Phi = Builder.CreatePHI(VoidPtrTy, 2);
594 Phi->addIncoming(NullPtr, EntryBB);
595 Phi->addIncoming(AllocateCall, AllocOrInvokeContBB);
596 auto *CoroBegin = Builder.CreateCall(
597 CGM.getIntrinsic(llvm::Intrinsic::coro_begin), {CoroId, Phi});
598 CurCoro.Data->CoroBegin = CoroBegin;
599
600 GetReturnObjectManager GroManager(*this, S);
601 GroManager.EmitGroAlloca();
602
603 CurCoro.Data->CleanupJD = getJumpDestInCurrentScope(RetBB);
604 {
605 CGDebugInfo *DI = getDebugInfo();
606 ParamReferenceReplacerRAII ParamReplacer(LocalDeclMap);
607 CodeGenFunction::RunCleanupsScope ResumeScope(*this);
608 EHStack.pushCleanup<CallCoroDelete>(NormalAndEHCleanup, S.getDeallocate());
609
610 // Create mapping between parameters and copy-params for coroutine function.
611 auto ParamMoves = S.getParamMoves();
612 assert((static_cast <bool> ((ParamMoves.size() == 0 || (ParamMoves
.size() == FnArgs.size())) && "ParamMoves and FnArgs should be the same size for coroutine function"
) ? void (0) : __assert_fail ("(ParamMoves.size() == 0 || (ParamMoves.size() == FnArgs.size())) && \"ParamMoves and FnArgs should be the same size for coroutine function\""
, "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 614, __extension__ __PRETTY_FUNCTION__))
613 (ParamMoves.size() == 0 || (ParamMoves.size() == FnArgs.size())) &&(static_cast <bool> ((ParamMoves.size() == 0 || (ParamMoves
.size() == FnArgs.size())) && "ParamMoves and FnArgs should be the same size for coroutine function"
) ? void (0) : __assert_fail ("(ParamMoves.size() == 0 || (ParamMoves.size() == FnArgs.size())) && \"ParamMoves and FnArgs should be the same size for coroutine function\""
, "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 614, __extension__ __PRETTY_FUNCTION__))
614 "ParamMoves and FnArgs should be the same size for coroutine function")(static_cast <bool> ((ParamMoves.size() == 0 || (ParamMoves
.size() == FnArgs.size())) && "ParamMoves and FnArgs should be the same size for coroutine function"
) ? void (0) : __assert_fail ("(ParamMoves.size() == 0 || (ParamMoves.size() == FnArgs.size())) && \"ParamMoves and FnArgs should be the same size for coroutine function\""
, "/build/llvm-toolchain-snapshot-13~++20210621111111+acefe0eaaf82/clang/lib/CodeGen/CGCoroutine.cpp"
, 614, __extension__ __PRETTY_FUNCTION__))
;
615 if (ParamMoves.size() == FnArgs.size() && DI)
616 for (const auto Pair : llvm::zip(FnArgs, ParamMoves))
617 DI->getCoroutineParameterMappings().insert(
618 {std::get<0>(Pair), std::get<1>(Pair)});
619
620 // Create parameter copies. We do it before creating a promise, since an
621 // evolution of coroutine TS may allow promise constructor to observe
622 // parameter copies.
623 for (auto *PM : S.getParamMoves()) {
624 EmitStmt(PM);
625 ParamReplacer.addCopy(cast<DeclStmt>(PM));
626 // TODO: if(CoroParam(...)) need to surround ctor and dtor
627 // for the copy, so that llvm can elide it if the copy is
628 // not needed.
629 }
630
631 EmitStmt(S.getPromiseDeclStmt());
632
633 Address PromiseAddr = GetAddrOfLocalVar(S.getPromiseDecl());
634 auto *PromiseAddrVoidPtr =
635 new llvm::BitCastInst(PromiseAddr.getPointer(), VoidPtrTy, "", CoroId);
636 // Update CoroId to refer to the promise. We could not do it earlier because
637 // promise local variable was not emitted yet.
638 CoroId->setArgOperand(1, PromiseAddrVoidPtr);
639
640 // Now we have the promise, initialize the GRO
641 GroManager.EmitGroInit();
642
643 EHStack.pushCleanup<CallCoroEnd>(EHCleanup);
644
645 CurCoro.Data->CurrentAwaitKind = AwaitKind::Init;
646 CurCoro.Data->ExceptionHandler = S.getExceptionHandler();
647 EmitStmt(S.getInitSuspendStmt());
648 CurCoro.Data->FinalJD = getJumpDestInCurrentScope(FinalBB);
649
650 CurCoro.Data->CurrentAwaitKind = AwaitKind::Normal;
651
652 if (CurCoro.Data->ExceptionHandler) {
653 // If we generated IR to record whether an exception was thrown from
654 // 'await_resume', then use that IR to determine whether the coroutine
655 // body should be skipped.
656 // If we didn't generate the IR (perhaps because 'await_resume' was marked
657 // as 'noexcept'), then we skip this check.
658 BasicBlock *ContBB = nullptr;
659 if (CurCoro.Data->ResumeEHVar) {
660 BasicBlock *BodyBB = createBasicBlock("coro.resumed.body");
661 ContBB = createBasicBlock("coro.resumed.cont");
662 Value *SkipBody = Builder.CreateFlagLoad(CurCoro.Data->ResumeEHVar,
663 "coro.resumed.eh");
664 Builder.CreateCondBr(SkipBody, ContBB, BodyBB);
665 EmitBlock(BodyBB);
666 }
667
668 auto Loc = S.getBeginLoc();
669 CXXCatchStmt Catch(Loc, /*exDecl=*/nullptr,
670 CurCoro.Data->ExceptionHandler);
671 auto *TryStmt =
672 CXXTryStmt::Create(getContext(), Loc, S.getBody(), &Catch);
673
674 EnterCXXTryStmt(*TryStmt);
675 emitBodyAndFallthrough(*this, S, TryStmt->getTryBlock());
676 ExitCXXTryStmt(*TryStmt);
677
678 if (ContBB)
679 EmitBlock(ContBB);
680 }
681 else {
682 emitBodyAndFallthrough(*this, S, S.getBody());
683 }
684
685 // See if we need to generate final suspend.
686 const bool CanFallthrough = Builder.GetInsertBlock();
687 const bool HasCoreturns = CurCoro.Data->CoreturnCount > 0;
688 if (CanFallthrough || HasCoreturns) {
689 EmitBlock(FinalBB);
690 CurCoro.Data->CurrentAwaitKind = AwaitKind::Final;
691 EmitStmt(S.getFinalSuspendStmt());
692 } else {
693 // We don't need FinalBB. Emit it to make sure the block is deleted.
694 EmitBlock(FinalBB, /*IsFinished=*/true);
695 }
696 }
697
698 EmitBlock(RetBB);
699 // Emit coro.end before getReturnStmt (and parameter destructors), since
700 // resume and destroy parts of the coroutine should not include them.
701 llvm::Function *CoroEnd = CGM.getIntrinsic(llvm::Intrinsic::coro_end);
702 Builder.CreateCall(CoroEnd, {NullPtr, Builder.getFalse()});
703
704 if (Stmt *Ret = S.getReturnStmt())
705 EmitStmt(Ret);
706}
707
708// Emit coroutine intrinsic and patch up arguments of the token type.
709RValue CodeGenFunction::EmitCoroutineIntrinsic(const CallExpr *E,
710 unsigned int IID) {
711 SmallVector<llvm::Value *, 8> Args;
712 switch (IID) {
713 default:
714 break;
715 // The coro.frame builtin is replaced with an SSA value of the coro.begin
716 // intrinsic.
717 case llvm::Intrinsic::coro_frame: {
718 if (CurCoro.Data && CurCoro.Data->CoroBegin) {
719 return RValue::get(CurCoro.Data->CoroBegin);
720 }
721 CGM.Error(E->getBeginLoc(), "this builtin expect that __builtin_coro_begin "
722 "has been used earlier in this function");
723 auto NullPtr = llvm::ConstantPointerNull::get(Builder.getInt8PtrTy());
724 return RValue::get(NullPtr);
725 }
726 // The following three intrinsics take a token parameter referring to a token
727 // returned by earlier call to @llvm.coro.id. Since we cannot represent it in
728 // builtins, we patch it up here.
729 case llvm::Intrinsic::coro_alloc:
730 case llvm::Intrinsic::coro_begin:
731 case llvm::Intrinsic::coro_free: {
732 if (CurCoro.Data && CurCoro.Data->CoroId) {
733 Args.push_back(CurCoro.Data->CoroId);
734 break;
735 }
736 CGM.Error(E->getBeginLoc(), "this builtin expect that __builtin_coro_id has"
737 " been used earlier in this function");
738 // Fallthrough to the next case to add TokenNone as the first argument.
739 LLVM_FALLTHROUGH[[gnu::fallthrough]];
740 }
741 // @llvm.coro.suspend takes a token parameter. Add token 'none' as the first
742 // argument.
743 case llvm::Intrinsic::coro_suspend:
744 Args.push_back(llvm::ConstantTokenNone::get(getLLVMContext()));
745 break;
746 }
747 for (const Expr *Arg : E->arguments())
748 Args.push_back(EmitScalarExpr(Arg));
749
750 llvm::Function *F = CGM.getIntrinsic(IID);
751 llvm::CallInst *Call = Builder.CreateCall(F, Args);
752
753 // Note: The following code is to enable to emit coro.id and coro.begin by
754 // hand to experiment with coroutines in C.
755 // If we see @llvm.coro.id remember it in the CoroData. We will update
756 // coro.alloc, coro.begin and coro.free intrinsics to refer to it.
757 if (IID == llvm::Intrinsic::coro_id) {
758 createCoroData(*this, CurCoro, Call, E);
759 }
760 else if (IID == llvm::Intrinsic::coro_begin) {
761 if (CurCoro.Data)
762 CurCoro.Data->CoroBegin = Call;
763 }
764 else if (IID == llvm::Intrinsic::coro_free) {
765 // Remember the last coro_free as we need it to build the conditional
766 // deletion of the coroutine frame.
767 if (CurCoro.Data)
768 CurCoro.Data->LastCoroFree = Call;
769 }
770 return RValue::get(Call);
771}

/usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/bits/unique_ptr.h

1// unique_ptr implementation -*- C++ -*-
2
3// Copyright (C) 2008-2020 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/** @file bits/unique_ptr.h
26 * This is an internal header file, included by other library headers.
27 * Do not attempt to use it directly. @headername{memory}
28 */
29
30#ifndef _UNIQUE_PTR_H1
31#define _UNIQUE_PTR_H1 1
32
33#include <bits/c++config.h>
34#include <debug/assertions.h>
35#include <type_traits>
36#include <utility>
37#include <tuple>
38#include <bits/stl_function.h>
39#include <bits/functional_hash.h>
40#if __cplusplus201402L > 201703L
41# include <compare>
42# include <ostream>
43#endif
44
45namespace std _GLIBCXX_VISIBILITY(default)__attribute__ ((__visibility__ ("default")))
46{
47_GLIBCXX_BEGIN_NAMESPACE_VERSION
48
49 /**
50 * @addtogroup pointer_abstractions
51 * @{
52 */
53
54#if _GLIBCXX_USE_DEPRECATED1
55#pragma GCC diagnostic push
56#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
57 template<typename> class auto_ptr;
58#pragma GCC diagnostic pop
59#endif
60
61 /// Primary template of default_delete, used by unique_ptr for single objects
62 template<typename _Tp>
63 struct default_delete
64 {
65 /// Default constructor
66 constexpr default_delete() noexcept = default;
67
68 /** @brief Converting constructor.
69 *
70 * Allows conversion from a deleter for objects of another type, `_Up`,
71 * only if `_Up*` is convertible to `_Tp*`.
72 */
73 template<typename _Up,
74 typename = _Require<is_convertible<_Up*, _Tp*>>>
75 default_delete(const default_delete<_Up>&) noexcept { }
76
77 /// Calls `delete __ptr`
78 void
79 operator()(_Tp* __ptr) const
80 {
81 static_assert(!is_void<_Tp>::value,
82 "can't delete pointer to incomplete type");
83 static_assert(sizeof(_Tp)>0,
84 "can't delete pointer to incomplete type");
85 delete __ptr;
86 }
87 };
88
89 // _GLIBCXX_RESOLVE_LIB_DEFECTS
90 // DR 740 - omit specialization for array objects with a compile time length
91
92 /// Specialization of default_delete for arrays, used by `unique_ptr<T[]>`
93 template<typename _Tp>
94 struct default_delete<_Tp[]>
95 {
96 public:
97 /// Default constructor
98 constexpr default_delete() noexcept = default;
99
100 /** @brief Converting constructor.
101 *
102 * Allows conversion from a deleter for arrays of another type, such as
103 * a const-qualified version of `_Tp`.
104 *
105 * Conversions from types derived from `_Tp` are not allowed because
106 * it is undefined to `delete[]` an array of derived types through a
107 * pointer to the base type.
108 */
109 template<typename _Up,
110 typename = _Require<is_convertible<_Up(*)[], _Tp(*)[]>>>
111 default_delete(const default_delete<_Up[]>&) noexcept { }
112
113 /// Calls `delete[] __ptr`
114 template<typename _Up>
115 typename enable_if<is_convertible<_Up(*)[], _Tp(*)[]>::value>::type
116 operator()(_Up* __ptr) const
117 {
118 static_assert(sizeof(_Tp)>0,
119 "can't delete pointer to incomplete type");
120 delete [] __ptr;
121 }
122 };
123
124 /// @cond undocumented
125
126 // Manages the pointer and deleter of a unique_ptr
127 template <typename _Tp, typename _Dp>
128 class __uniq_ptr_impl
129 {
130 template <typename _Up, typename _Ep, typename = void>
131 struct _Ptr
132 {
133 using type = _Up*;
134 };
135
136 template <typename _Up, typename _Ep>
137 struct
138 _Ptr<_Up, _Ep, __void_t<typename remove_reference<_Ep>::type::pointer>>
139 {
140 using type = typename remove_reference<_Ep>::type::pointer;
141 };
142
143 public:
144 using _DeleterConstraint = enable_if<
145 __and_<__not_<is_pointer<_Dp>>,
146 is_default_constructible<_Dp>>::value>;
147
148 using pointer = typename _Ptr<_Tp, _Dp>::type;
149
150 static_assert( !is_rvalue_reference<_Dp>::value,
151 "unique_ptr's deleter type must be a function object type"
152 " or an lvalue reference type" );
153
154 __uniq_ptr_impl() = default;
155 __uniq_ptr_impl(pointer __p) : _M_t() { _M_ptr() = __p; }
156
157 template<typename _Del>
158 __uniq_ptr_impl(pointer __p, _Del&& __d)
159 : _M_t(__p, std::forward<_Del>(__d)) { }
160
161 __uniq_ptr_impl(__uniq_ptr_impl&& __u) noexcept
162 : _M_t(std::move(__u._M_t))
163 { __u._M_ptr() = nullptr; }
164
165 __uniq_ptr_impl& operator=(__uniq_ptr_impl&& __u) noexcept
166 {
167 reset(__u.release());
168 _M_deleter() = std::forward<_Dp>(__u._M_deleter());
169 return *this;
170 }
171
172 pointer& _M_ptr() { return std::get<0>(_M_t); }
173 pointer _M_ptr() const { return std::get<0>(_M_t); }
174 _Dp& _M_deleter() { return std::get<1>(_M_t); }
175 const _Dp& _M_deleter() const { return std::get<1>(_M_t); }
176
177 void reset(pointer __p) noexcept
178 {
179 const pointer __old_p = _M_ptr();
180 _M_ptr() = __p;
181 if (__old_p)
182 _M_deleter()(__old_p);
183 }
184
185 pointer release() noexcept
186 {
187 pointer __p = _M_ptr();
188 _M_ptr() = nullptr;
189 return __p;
190 }
191
192 void
193 swap(__uniq_ptr_impl& __rhs) noexcept
194 {
195 using std::swap;
196 swap(this->_M_ptr(), __rhs._M_ptr());
197 swap(this->_M_deleter(), __rhs._M_deleter());
198 }
199
200 private:
201 tuple<pointer, _Dp> _M_t;
202 };
203
204 // Defines move construction + assignment as either defaulted or deleted.
205 template <typename _Tp, typename _Dp,
206 bool = is_move_constructible<_Dp>::value,
207 bool = is_move_assignable<_Dp>::value>
208 struct __uniq_ptr_data : __uniq_ptr_impl<_Tp, _Dp>
209 {
210 using __uniq_ptr_impl<_Tp, _Dp>::__uniq_ptr_impl;
211 __uniq_ptr_data(__uniq_ptr_data&&) = default;
212 __uniq_ptr_data& operator=(__uniq_ptr_data&&) = default;
213 };
214
215 template <typename _Tp, typename _Dp>
216 struct __uniq_ptr_data<_Tp, _Dp, true, false> : __uniq_ptr_impl<_Tp, _Dp>
217 {
218 using __uniq_ptr_impl<_Tp, _Dp>::__uniq_ptr_impl;
219 __uniq_ptr_data(__uniq_ptr_data&&) = default;
220 __uniq_ptr_data& operator=(__uniq_ptr_data&&) = delete;
221 };
222
223 template <typename _Tp, typename _Dp>
224 struct __uniq_ptr_data<_Tp, _Dp, false, true> : __uniq_ptr_impl<_Tp, _Dp>
225 {
226 using __uniq_ptr_impl<_Tp, _Dp>::__uniq_ptr_impl;
227 __uniq_ptr_data(__uniq_ptr_data&&) = delete;
228 __uniq_ptr_data& operator=(__uniq_ptr_data&&) = default;
229 };
230
231 template <typename _Tp, typename _Dp>
232 struct __uniq_ptr_data<_Tp, _Dp, false, false> : __uniq_ptr_impl<_Tp, _Dp>
233 {
234 using __uniq_ptr_impl<_Tp, _Dp>::__uniq_ptr_impl;
235 __uniq_ptr_data(__uniq_ptr_data&&) = delete;
236 __uniq_ptr_data& operator=(__uniq_ptr_data&&) = delete;
237 };
238 /// @endcond
239
240 /// 20.7.1.2 unique_ptr for single objects.
241 template <typename _Tp, typename _Dp = default_delete<_Tp>>
242 class unique_ptr
243 {
244 template <typename _Up>
245 using _DeleterConstraint =
246 typename __uniq_ptr_impl<_Tp, _Up>::_DeleterConstraint::type;
247
248 __uniq_ptr_data<_Tp, _Dp> _M_t;
249
250 public:
251 using pointer = typename __uniq_ptr_impl<_Tp, _Dp>::pointer;
252 using element_type = _Tp;
253 using deleter_type = _Dp;
254
255 private:
256 // helper template for detecting a safe conversion from another
257 // unique_ptr
258 template<typename _Up, typename _Ep>
259 using __safe_conversion_up = __and_<
260 is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>,
261 __not_<is_array<_Up>>
262 >;
263
264 public:
265 // Constructors.
266
267 /// Default constructor, creates a unique_ptr that owns nothing.
268 template<typename _Del = _Dp, typename = _DeleterConstraint<_Del>>
269 constexpr unique_ptr() noexcept
270 : _M_t()
271 { }
272
273 /** Takes ownership of a pointer.
274 *
275 * @param __p A pointer to an object of @c element_type
276 *
277 * The deleter will be value-initialized.
278 */
279 template<typename _Del = _Dp, typename = _DeleterConstraint<_Del>>
280 explicit
281 unique_ptr(pointer __p) noexcept
282 : _M_t(__p)
283 { }
284
285 /** Takes ownership of a pointer.
286 *
287 * @param __p A pointer to an object of @c element_type
288 * @param __d A reference to a deleter.
289 *
290 * The deleter will be initialized with @p __d
291 */
292 template<typename _Del = deleter_type,
293 typename = _Require<is_copy_constructible<_Del>>>
294 unique_ptr(pointer __p, const deleter_type& __d) noexcept
295 : _M_t(__p, __d) { }
296
297 /** Takes ownership of a pointer.
298 *
299 * @param __p A pointer to an object of @c element_type
300 * @param __d An rvalue reference to a (non-reference) deleter.
301 *
302 * The deleter will be initialized with @p std::move(__d)
303 */
304 template<typename _Del = deleter_type,
305 typename = _Require<is_move_constructible<_Del>>>
306 unique_ptr(pointer __p,
307 __enable_if_t<!is_lvalue_reference<_Del>::value,
308 _Del&&> __d) noexcept
309 : _M_t(__p, std::move(__d))
310 { }
311
312 template<typename _Del = deleter_type,
313 typename _DelUnref = typename remove_reference<_Del>::type>
314 unique_ptr(pointer,
315 __enable_if_t<is_lvalue_reference<_Del>::value,
316 _DelUnref&&>) = delete;
317
318 /// Creates a unique_ptr that owns nothing.
319 template<typename _Del = _Dp, typename = _DeleterConstraint<_Del>>
320 constexpr unique_ptr(nullptr_t) noexcept
321 : _M_t()
322 { }
323
324 // Move constructors.
325
326 /// Move constructor.
327 unique_ptr(unique_ptr&&) = default;
328
329 /** @brief Converting constructor from another type
330 *
331 * Requires that the pointer owned by @p __u is convertible to the
332 * type of pointer owned by this object, @p __u does not own an array,
333 * and @p __u has a compatible deleter type.
334 */
335 template<typename _Up, typename _Ep, typename = _Require<
336 __safe_conversion_up<_Up, _Ep>,
337 typename conditional<is_reference<_Dp>::value,
338 is_same<_Ep, _Dp>,
339 is_convertible<_Ep, _Dp>>::type>>
340 unique_ptr(unique_ptr<_Up, _Ep>&& __u) noexcept
341 : _M_t(__u.release(), std::forward<_Ep>(__u.get_deleter()))
342 { }
343
344#if _GLIBCXX_USE_DEPRECATED1
345#pragma GCC diagnostic push
346#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
347 /// Converting constructor from @c auto_ptr
348 template<typename _Up, typename = _Require<
349 is_convertible<_Up*, _Tp*>, is_same<_Dp, default_delete<_Tp>>>>
350 unique_ptr(auto_ptr<_Up>&& __u) noexcept;
351#pragma GCC diagnostic pop
352#endif
353
354 /// Destructor, invokes the deleter if the stored pointer is not null.
355 ~unique_ptr() noexcept
356 {
357 static_assert(__is_invocable<deleter_type&, pointer>::value,
358 "unique_ptr's deleter must be invocable with a pointer");
359 auto& __ptr = _M_t._M_ptr();
360 if (__ptr != nullptr)
361 get_deleter()(std::move(__ptr));
362 __ptr = pointer();
363 }
364
365 // Assignment.
366
367 /** @brief Move assignment operator.
368 *
369 * Invokes the deleter if this object owns a pointer.
370 */
371 unique_ptr& operator=(unique_ptr&&) = default;
372
373 /** @brief Assignment from another type.
374 *
375 * @param __u The object to transfer ownership from, which owns a
376 * convertible pointer to a non-array object.
377 *
378 * Invokes the deleter if this object owns a pointer.
379 */
380 template<typename _Up, typename _Ep>
381 typename enable_if< __and_<
382 __safe_conversion_up<_Up, _Ep>,
383 is_assignable<deleter_type&, _Ep&&>
384 >::value,
385 unique_ptr&>::type
386 operator=(unique_ptr<_Up, _Ep>&& __u) noexcept
387 {
388 reset(__u.release());
389 get_deleter() = std::forward<_Ep>(__u.get_deleter());
390 return *this;
391 }
392
393 /// Reset the %unique_ptr to empty, invoking the deleter if necessary.
394 unique_ptr&
395 operator=(nullptr_t) noexcept
396 {
397 reset();
398 return *this;
399 }
400
401 // Observers.
402
403 /// Dereference the stored pointer.
404 typename add_lvalue_reference<element_type>::type
405 operator*() const
406 {
407 __glibcxx_assert(get() != pointer());
408 return *get();
409 }
410
411 /// Return the stored pointer.
412 pointer
413 operator->() const noexcept
414 {
415 _GLIBCXX_DEBUG_PEDASSERT(get() != pointer());
416 return get();
417 }
418
419 /// Return the stored pointer.
420 pointer
421 get() const noexcept
422 { return _M_t._M_ptr(); }
423
424 /// Return a reference to the stored deleter.
425 deleter_type&
426 get_deleter() noexcept
427 { return _M_t._M_deleter(); }
428
429 /// Return a reference to the stored deleter.
430 const deleter_type&
431 get_deleter() const noexcept
432 { return _M_t._M_deleter(); }
433
434 /// Return @c true if the stored pointer is not null.
435 explicit operator bool() const noexcept
436 { return get() == pointer() ? false : true; }
4
Assuming the condition is false
5
'?' condition is false
6
Returning the value 1, which participates in a condition later
437
438 // Modifiers.
439
440 /// Release ownership of any stored pointer.
441 pointer
442 release() noexcept
443 { return _M_t.release(); }
444
445 /** @brief Replace the stored pointer.
446 *
447 * @param __p The new pointer to store.
448 *
449 * The deleter will be invoked if a pointer is already owned.
450 */
451 void
452 reset(pointer __p = pointer()) noexcept
453 {
454 static_assert(__is_invocable<deleter_type&, pointer>::value,
455 "unique_ptr's deleter must be invocable with a pointer");
456 _M_t.reset(std::move(__p));
457 }
458
459 /// Exchange the pointer and deleter with another object.
460 void
461 swap(unique_ptr& __u) noexcept
462 {
463 static_assert(__is_swappable<_Dp>::value, "deleter must be swappable");
464 _M_t.swap(__u._M_t);
465 }
466
467 // Disable copy from lvalue.
468 unique_ptr(const unique_ptr&) = delete;
469 unique_ptr& operator=(const unique_ptr&) = delete;
470 };
471
472 /// 20.7.1.3 unique_ptr for array objects with a runtime length
473 // [unique.ptr.runtime]
474 // _GLIBCXX_RESOLVE_LIB_DEFECTS
475 // DR 740 - omit specialization for array objects with a compile time length
476 template<typename _Tp, typename _Dp>
477 class unique_ptr<_Tp[], _Dp>
478 {
479 template <typename _Up>
480 using _DeleterConstraint =
481 typename __uniq_ptr_impl<_Tp, _Up>::_DeleterConstraint::type;
482
483 __uniq_ptr_data<_Tp, _Dp> _M_t;
484
485 template<typename _Up>
486 using __remove_cv = typename remove_cv<_Up>::type;
487
488 // like is_base_of<_Tp, _Up> but false if unqualified types are the same
489 template<typename _Up>
490 using __is_derived_Tp
491 = __and_< is_base_of<_Tp, _Up>,
492 __not_<is_same<__remove_cv<_Tp>, __remove_cv<_Up>>> >;
493
494 public:
495 using pointer = typename __uniq_ptr_impl<_Tp, _Dp>::pointer;
496 using element_type = _Tp;
497 using deleter_type = _Dp;
498
499 // helper template for detecting a safe conversion from another
500 // unique_ptr
501 template<typename _Up, typename _Ep,
502 typename _UPtr = unique_ptr<_Up, _Ep>,
503 typename _UP_pointer = typename _UPtr::pointer,
504 typename _UP_element_type = typename _UPtr::element_type>
505 using __safe_conversion_up = __and_<
506 is_array<_Up>,
507 is_same<pointer, element_type*>,
508 is_same<_UP_pointer, _UP_element_type*>,
509 is_convertible<_UP_element_type(*)[], element_type(*)[]>
510 >;
511
512 // helper template for detecting a safe conversion from a raw pointer
513 template<typename _Up>
514 using __safe_conversion_raw = __and_<
515 __or_<__or_<is_same<_Up, pointer>,
516 is_same<_Up, nullptr_t>>,
517 __and_<is_pointer<_Up>,
518 is_same<pointer, element_type*>,
519 is_convertible<
520 typename remove_pointer<_Up>::type(*)[],
521 element_type(*)[]>
522 >
523 >
524 >;
525
526 // Constructors.
527
528 /// Default constructor, creates a unique_ptr that owns nothing.
529 template<typename _Del = _Dp, typename = _DeleterConstraint<_Del>>
530 constexpr unique_ptr() noexcept
531 : _M_t()
532 { }
533
534 /** Takes ownership of a pointer.
535 *
536 * @param __p A pointer to an array of a type safely convertible
537 * to an array of @c element_type
538 *
539 * The deleter will be value-initialized.
540 */
541 template<typename _Up,
542 typename _Vp = _Dp,
543 typename = _DeleterConstraint<_Vp>,
544 typename = typename enable_if<
545 __safe_conversion_raw<_Up>::value, bool>::type>
546 explicit
547 unique_ptr(_Up __p) noexcept
548 : _M_t(__p)
549 { }
550
551 /** Takes ownership of a pointer.
552 *
553 * @param __p A pointer to an array of a type safely convertible
554 * to an array of @c element_type
555 * @param __d A reference to a deleter.
556 *
557 * The deleter will be initialized with @p __d
558 */
559 template<typename _Up, typename _Del = deleter_type,
560 typename = _Require<__safe_conversion_raw<_Up>,
561 is_copy_constructible<_Del>>>
562 unique_ptr(_Up __p, const deleter_type& __d) noexcept
563 : _M_t(__p, __d) { }
564
565 /** Takes ownership of a pointer.
566 *
567 * @param __p A pointer to an array of a type safely convertible
568 * to an array of @c element_type
569 * @param __d A reference to a deleter.
570 *
571 * The deleter will be initialized with @p std::move(__d)
572 */
573 template<typename _Up, typename _Del = deleter_type,
574 typename = _Require<__safe_conversion_raw<_Up>,
575 is_move_constructible<_Del>>>
576 unique_ptr(_Up __p,
577 __enable_if_t<!is_lvalue_reference<_Del>::value,
578 _Del&&> __d) noexcept
579 : _M_t(std::move(__p), std::move(__d))
580 { }
581
582 template<typename _Up, typename _Del = deleter_type,
583 typename _DelUnref = typename remove_reference<_Del>::type,
584 typename = _Require<__safe_conversion_raw<_Up>>>
585 unique_ptr(_Up,
586 __enable_if_t<is_lvalue_reference<_Del>::value,
587 _DelUnref&&>) = delete;
588
589 /// Move constructor.
590 unique_ptr(unique_ptr&&) = default;
591
592 /// Creates a unique_ptr that owns nothing.
593 template<typename _Del = _Dp, typename = _DeleterConstraint<_Del>>
594 constexpr unique_ptr(nullptr_t) noexcept
595 : _M_t()
596 { }
597
598 template<typename _Up, typename _Ep, typename = _Require<
599 __safe_conversion_up<_Up, _Ep>,
600 typename conditional<is_reference<_Dp>::value,
601 is_same<_Ep, _Dp>,
602 is_convertible<_Ep, _Dp>>::type>>
603 unique_ptr(unique_ptr<_Up, _Ep>&& __u) noexcept
604 : _M_t(__u.release(), std::forward<_Ep>(__u.get_deleter()))
605 { }
606
607 /// Destructor, invokes the deleter if the stored pointer is not null.
608 ~unique_ptr()
609 {
610 auto& __ptr = _M_t._M_ptr();
611 if (__ptr != nullptr)
612 get_deleter()(__ptr);
613 __ptr = pointer();
614 }
615
616 // Assignment.
617
618 /** @brief Move assignment operator.
619 *
620 * Invokes the deleter if this object owns a pointer.
621 */
622 unique_ptr&
623 operator=(unique_ptr&&) = default;
624
625 /** @brief Assignment from another type.
626 *
627 * @param __u The object to transfer ownership from, which owns a
628 * convertible pointer to an array object.
629 *
630 * Invokes the deleter if this object owns a pointer.
631 */
632 template<typename _Up, typename _Ep>
633 typename
634 enable_if<__and_<__safe_conversion_up<_Up, _Ep>,
635 is_assignable<deleter_type&, _Ep&&>
636 >::value,
637 unique_ptr&>::type
638 operator=(unique_ptr<_Up, _Ep>&& __u) noexcept
639 {
640 reset(__u.release());
641 get_deleter() = std::forward<_Ep>(__u.get_deleter());
642 return *this;
643 }
644
645 /// Reset the %unique_ptr to empty, invoking the deleter if necessary.
646 unique_ptr&
647 operator=(nullptr_t) noexcept
648 {
649 reset();
650 return *this;
651 }
652
653 // Observers.
654
655 /// Access an element of owned array.
656 typename std::add_lvalue_reference<element_type>::type
657 operator[](size_t __i) const
658 {
659 __glibcxx_assert(get() != pointer());
660 return get()[__i];
661 }
662
663 /// Return the stored pointer.
664 pointer
665 get() const noexcept
666 { return _M_t._M_ptr(); }
667
668 /// Return a reference to the stored deleter.
669 deleter_type&
670 get_deleter() noexcept
671 { return _M_t._M_deleter(); }
672
673 /// Return a reference to the stored deleter.
674 const deleter_type&
675 get_deleter() const noexcept
676 { return _M_t._M_deleter(); }
677
678 /// Return @c true if the stored pointer is not null.
679 explicit operator bool() const noexcept
680 { return get() == pointer() ? false : true; }
681
682 // Modifiers.
683
684 /// Release ownership of any stored pointer.
685 pointer
686 release() noexcept
687 { return _M_t.release(); }
688
689 /** @brief Replace the stored pointer.
690 *
691 * @param __p The new pointer to store.
692 *
693 * The deleter will be invoked if a pointer is already owned.
694 */
695 template <typename _Up,
696 typename = _Require<
697 __or_<is_same<_Up, pointer>,
698 __and_<is_same<pointer, element_type*>,
699 is_pointer<_Up>,
700 is_convertible<
701 typename remove_pointer<_Up>::type(*)[],
702 element_type(*)[]
703 >
704 >
705 >
706 >>
707 void
708 reset(_Up __p) noexcept
709 { _M_t.reset(std::move(__p)); }
710
711 void reset(nullptr_t = nullptr) noexcept
712 { reset(pointer()); }
713
714 /// Exchange the pointer and deleter with another object.
715 void
716 swap(unique_ptr& __u) noexcept
717 {
718 static_assert(__is_swappable<_Dp>::value, "deleter must be swappable");
719 _M_t.swap(__u._M_t);
720 }
721
722 // Disable copy from lvalue.
723 unique_ptr(const unique_ptr&) = delete;
724 unique_ptr& operator=(const unique_ptr&) = delete;
725 };
726
727 /// @relates unique_ptr @{
728
729 /// Swap overload for unique_ptr
730 template<typename _Tp, typename _Dp>
731 inline
732#if __cplusplus201402L > 201402L || !defined(__STRICT_ANSI__1) // c++1z or gnu++11
733 // Constrained free swap overload, see p0185r1
734 typename enable_if<__is_swappable<_Dp>::value>::type
735#else
736 void
737#endif
738 swap(unique_ptr<_Tp, _Dp>& __x,
739 unique_ptr<_Tp, _Dp>& __y) noexcept
740 { __x.swap(__y); }
741
742#if __cplusplus201402L > 201402L || !defined(__STRICT_ANSI__1) // c++1z or gnu++11
743 template<typename _Tp, typename _Dp>
744 typename enable_if<!__is_swappable<_Dp>::value>::type
745 swap(unique_ptr<_Tp, _Dp>&,
746 unique_ptr<_Tp, _Dp>&) = delete;
747#endif
748
749 /// Equality operator for unique_ptr objects, compares the owned pointers
750 template<typename _Tp, typename _Dp,
751 typename _Up, typename _Ep>
752 _GLIBCXX_NODISCARD inline bool
753 operator==(const unique_ptr<_Tp, _Dp>& __x,
754 const unique_ptr<_Up, _Ep>& __y)
755 { return __x.get() == __y.get(); }
756
757 /// unique_ptr comparison with nullptr
758 template<typename _Tp, typename _Dp>
759 _GLIBCXX_NODISCARD inline bool
760 operator==(const unique_ptr<_Tp, _Dp>& __x, nullptr_t) noexcept
761 { return !__x; }
762
763#ifndef __cpp_lib_three_way_comparison
764 /// unique_ptr comparison with nullptr
765 template<typename _Tp, typename _Dp>
766 _GLIBCXX_NODISCARD inline bool
767 operator==(nullptr_t, const unique_ptr<_Tp, _Dp>& __x) noexcept
768 { return !__x; }
769
770 /// Inequality operator for unique_ptr objects, compares the owned pointers
771 template<typename _Tp, typename _Dp,
772 typename _Up, typename _Ep>
773 _GLIBCXX_NODISCARD inline bool
774 operator!=(const unique_ptr<_Tp, _Dp>& __x,
775 const unique_ptr<_Up, _Ep>& __y)
776 { return __x.get() != __y.get(); }
777
778 /// unique_ptr comparison with nullptr
779 template<typename _Tp, typename _Dp>
780 _GLIBCXX_NODISCARD inline bool
781 operator!=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t) noexcept
782 { return (bool)__x; }
783
784 /// unique_ptr comparison with nullptr
785 template<typename _Tp, typename _Dp>
786 _GLIBCXX_NODISCARD inline bool
787 operator!=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x) noexcept
788 { return (bool)__x; }
789#endif // three way comparison
790
791 /// Relational operator for unique_ptr objects, compares the owned pointers
792 template<typename _Tp, typename _Dp,
793 typename _Up, typename _Ep>
794 _GLIBCXX_NODISCARD inline bool
795 operator<(const unique_ptr<_Tp, _Dp>& __x,
796 const unique_ptr<_Up, _Ep>& __y)
797 {
798 typedef typename
799 std::common_type<typename unique_ptr<_Tp, _Dp>::pointer,
800 typename unique_ptr<_Up, _Ep>::pointer>::type _CT;
801 return std::less<_CT>()(__x.get(), __y.get());
802 }
803
804 /// unique_ptr comparison with nullptr
805 template<typename _Tp, typename _Dp>
806 _GLIBCXX_NODISCARD inline bool
807 operator<(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
808 {
809 return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(__x.get(),
810 nullptr);
811 }
812
813 /// unique_ptr comparison with nullptr
814 template<typename _Tp, typename _Dp>
815 _GLIBCXX_NODISCARD inline bool
816 operator<(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
817 {
818 return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(nullptr,
819 __x.get());
820 }
821
822 /// Relational operator for unique_ptr objects, compares the owned pointers
823 template<typename _Tp, typename _Dp,
824 typename _Up, typename _Ep>
825 _GLIBCXX_NODISCARD inline bool
826 operator<=(const unique_ptr<_Tp, _Dp>& __x,
827 const unique_ptr<_Up, _Ep>& __y)
828 { return !(__y < __x); }
829
830 /// unique_ptr comparison with nullptr
831 template<typename _Tp, typename _Dp>
832 _GLIBCXX_NODISCARD inline bool
833 operator<=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
834 { return !(nullptr < __x); }
835
836 /// unique_ptr comparison with nullptr
837 template<typename _Tp, typename _Dp>
838 _GLIBCXX_NODISCARD inline bool
839 operator<=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
840 { return !(__x < nullptr); }
841
842 /// Relational operator for unique_ptr objects, compares the owned pointers
843 template<typename _Tp, typename _Dp,
844 typename _Up, typename _Ep>
845 _GLIBCXX_NODISCARD inline bool
846 operator>(const unique_ptr<_Tp, _Dp>& __x,
847 const unique_ptr<_Up, _Ep>& __y)
848 { return (__y < __x); }
849
850 /// unique_ptr comparison with nullptr
851 template<typename _Tp, typename _Dp>
852 _GLIBCXX_NODISCARD inline bool
853 operator>(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
854 {
855 return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(nullptr,
856 __x.get());
857 }
858
859 /// unique_ptr comparison with nullptr
860 template<typename _Tp, typename _Dp>
861 _GLIBCXX_NODISCARD inline bool
862 operator>(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
863 {
864 return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(__x.get(),
865 nullptr);
866 }
867
868 /// Relational operator for unique_ptr objects, compares the owned pointers
869 template<typename _Tp, typename _Dp,
870 typename _Up, typename _Ep>
871 _GLIBCXX_NODISCARD inline bool
872 operator>=(const unique_ptr<_Tp, _Dp>& __x,
873 const unique_ptr<_Up, _Ep>& __y)
874 { return !(__x < __y); }
875
876 /// unique_ptr comparison with nullptr
877 template<typename _Tp, typename _Dp>
878 _GLIBCXX_NODISCARD inline bool
879 operator>=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
880 { return !(__x < nullptr); }
881
882 /// unique_ptr comparison with nullptr
883 template<typename _Tp, typename _Dp>
884 _GLIBCXX_NODISCARD inline bool
885 operator>=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
886 { return !(nullptr < __x); }
887
888#ifdef __cpp_lib_three_way_comparison
889 template<typename _Tp, typename _Dp, typename _Up, typename _Ep>
890 requires three_way_comparable_with<typename unique_ptr<_Tp, _Dp>::pointer,
891 typename unique_ptr<_Up, _Ep>::pointer>
892 inline
893 compare_three_way_result_t<typename unique_ptr<_Tp, _Dp>::pointer,
894 typename unique_ptr<_Up, _Ep>::pointer>
895 operator<=>(const unique_ptr<_Tp, _Dp>& __x,
896 const unique_ptr<_Up, _Ep>& __y)
897 { return compare_three_way()(__x.get(), __y.get()); }
898
899 template<typename _Tp, typename _Dp>
900 requires three_way_comparable<typename unique_ptr<_Tp, _Dp>::pointer>
901 inline
902 compare_three_way_result_t<typename unique_ptr<_Tp, _Dp>::pointer>
903 operator<=>(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
904 {
905 using pointer = typename unique_ptr<_Tp, _Dp>::pointer;
906 return compare_three_way()(__x.get(), static_cast<pointer>(nullptr));
907 }
908#endif
909 // @} relates unique_ptr
910
911 /// @cond undocumented
912 template<typename _Up, typename _Ptr = typename _Up::pointer,
913 bool = __poison_hash<_Ptr>::__enable_hash_call>
914 struct __uniq_ptr_hash
915#if ! _GLIBCXX_INLINE_VERSION0
916 : private __poison_hash<_Ptr>
917#endif
918 {
919 size_t
920 operator()(const _Up& __u) const
921 noexcept(noexcept(std::declval<hash<_Ptr>>()(std::declval<_Ptr>())))
922 { return hash<_Ptr>()(__u.get()); }
923 };
924
925 template<typename _Up, typename _Ptr>
926 struct __uniq_ptr_hash<_Up, _Ptr, false>
927 : private __poison_hash<_Ptr>
928 { };
929 /// @endcond
930
931 /// std::hash specialization for unique_ptr.
932 template<typename _Tp, typename _Dp>
933 struct hash<unique_ptr<_Tp, _Dp>>
934 : public __hash_base<size_t, unique_ptr<_Tp, _Dp>>,
935 public __uniq_ptr_hash<unique_ptr<_Tp, _Dp>>
936 { };
937
938#if __cplusplus201402L >= 201402L
939 /// @relates unique_ptr @{
940#define __cpp_lib_make_unique201304 201304
941
942 /// @cond undocumented
943
944 template<typename _Tp>
945 struct _MakeUniq
946 { typedef unique_ptr<_Tp> __single_object; };
947
948 template<typename _Tp>
949 struct _MakeUniq<_Tp[]>
950 { typedef unique_ptr<_Tp[]> __array; };
951
952 template<typename _Tp, size_t _Bound>
953 struct _MakeUniq<_Tp[_Bound]>
954 { struct __invalid_type { }; };
955
956 /// @endcond
957
958 /// std::make_unique for single objects
959 template<typename _Tp, typename... _Args>
960 inline typename _MakeUniq<_Tp>::__single_object
961 make_unique(_Args&&... __args)
962 { return unique_ptr<_Tp>(new _Tp(std::forward<_Args>(__args)...)); }
963
964 /// std::make_unique for arrays of unknown bound
965 template<typename _Tp>
966 inline typename _MakeUniq<_Tp>::__array
967 make_unique(size_t __num)
968 { return unique_ptr<_Tp>(new remove_extent_t<_Tp>[__num]()); }
969
970 /// Disable std::make_unique for arrays of known bound
971 template<typename _Tp, typename... _Args>
972 inline typename _MakeUniq<_Tp>::__invalid_type
973 make_unique(_Args&&...) = delete;
974 // @} relates unique_ptr
975#endif // C++14
976
977#if __cplusplus201402L > 201703L && __cpp_concepts
978 // _GLIBCXX_RESOLVE_LIB_DEFECTS
979 // 2948. unique_ptr does not define operator<< for stream output
980 /// Stream output operator for unique_ptr
981 template<typename _CharT, typename _Traits, typename _Tp, typename _Dp>
982 inline basic_ostream<_CharT, _Traits>&
983 operator<<(basic_ostream<_CharT, _Traits>& __os,
984 const unique_ptr<_Tp, _Dp>& __p)
985 requires requires { __os << __p.get(); }
986 {
987 __os << __p.get();
988 return __os;
989 }
990#endif // C++20
991
992 // @} group pointer_abstractions
993
994#if __cplusplus201402L >= 201703L
995 namespace __detail::__variant
996 {
997 template<typename> struct _Never_valueless_alt; // see <variant>
998
999 // Provide the strong exception-safety guarantee when emplacing a
1000 // unique_ptr into a variant.
1001 template<typename _Tp, typename _Del>
1002 struct _Never_valueless_alt<std::unique_ptr<_Tp, _Del>>
1003 : std::true_type
1004 { };
1005 } // namespace __detail::__variant
1006#endif // C++17
1007
1008_GLIBCXX_END_NAMESPACE_VERSION
1009} // namespace
1010
1011#endif /* _UNIQUE_PTR_H */