Bug Summary

File:llvm/lib/Analysis/LoopNestAnalysis.cpp
Warning:line 230, column 3
Returning null reference

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 LoopNestAnalysis.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 -fhalf-no-semantic-interposition -mframe-pointer=none -fmath-errno -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -fno-split-dwarf-inlining -debugger-tuning=gdb -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-12/lib/clang/12.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-12~++20210125100614+2cdb34efdac5/build-llvm/lib/Analysis -I /build/llvm-toolchain-snapshot-12~++20210125100614+2cdb34efdac5/llvm/lib/Analysis -I /build/llvm-toolchain-snapshot-12~++20210125100614+2cdb34efdac5/build-llvm/include -I /build/llvm-toolchain-snapshot-12~++20210125100614+2cdb34efdac5/llvm/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-12/lib/clang/12.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-12~++20210125100614+2cdb34efdac5/build-llvm/lib/Analysis -fdebug-prefix-map=/build/llvm-toolchain-snapshot-12~++20210125100614+2cdb34efdac5=. -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 -o /tmp/scan-build-2021-01-26-035717-31997-1 -x c++ /build/llvm-toolchain-snapshot-12~++20210125100614+2cdb34efdac5/llvm/lib/Analysis/LoopNestAnalysis.cpp

/build/llvm-toolchain-snapshot-12~++20210125100614+2cdb34efdac5/llvm/lib/Analysis/LoopNestAnalysis.cpp

→
1//===- LoopNestAnalysis.cpp - Loop Nest Analysis --------------------------==//
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/// \file
10/// The implementation for the loop nest analysis.
11///
12//===----------------------------------------------------------------------===//
13
14#include "llvm/Analysis/LoopNestAnalysis.h"
15#include "llvm/ADT/BreadthFirstIterator.h"
16#include "llvm/ADT/Statistic.h"
17#include "llvm/Analysis/PostDominators.h"
18#include "llvm/Analysis/ValueTracking.h"
19
20using namespace llvm;
21
22#define DEBUG_TYPE"loopnest" "loopnest"
23#ifndef NDEBUG
24static const char *VerboseDebug = DEBUG_TYPE"loopnest" "-verbose";
25#endif
26
27/// Determine whether the loops structure violates basic requirements for
28/// perfect nesting:
29/// - the inner loop should be the outer loop's only child
30/// - the outer loop header should 'flow' into the inner loop preheader
31/// or jump around the inner loop to the outer loop latch
32/// - if the inner loop latch exits the inner loop, it should 'flow' into
33/// the outer loop latch.
34/// Returns true if the loop structure satisfies the basic requirements and
35/// false otherwise.
36static bool checkLoopsStructure(const Loop &OuterLoop, const Loop &InnerLoop,
37 ScalarEvolution &SE);
38
39//===----------------------------------------------------------------------===//
40// LoopNest implementation
41//
42
43LoopNest::LoopNest(Loop &Root, ScalarEvolution &SE)
44 : MaxPerfectDepth(getMaxPerfectDepth(Root, SE)) {
4
←
Calling 'LoopNest::getMaxPerfectDepth'
→
45 append_range(Loops, breadth_first(&Root));
46}
47
48std::unique_ptr<LoopNest> LoopNest::getLoopNest(Loop &Root,
49 ScalarEvolution &SE) {
50 return std::make_unique<LoopNest>(Root, SE);
2
←
Calling 'make_unique<llvm::LoopNest, llvm::Loop &, llvm::ScalarEvolution &>'
→
51}
52
53bool LoopNest::arePerfectlyNested(const Loop &OuterLoop, const Loop &InnerLoop,
54 ScalarEvolution &SE) {
55 assert(!OuterLoop.isInnermost() && "Outer loop should have subloops")((!OuterLoop.isInnermost() && "Outer loop should have subloops"
) ? static_cast<void> (0) : __assert_fail ("!OuterLoop.isInnermost() && \"Outer loop should have subloops\""
, "/build/llvm-toolchain-snapshot-12~++20210125100614+2cdb34efdac5/llvm/lib/Analysis/LoopNestAnalysis.cpp"
, 55, __PRETTY_FUNCTION__));
10
←
Assuming the condition is true
→
11
←
'?' condition is true
→
56 assert(!InnerLoop.isOutermost() && "Inner loop should have a parent")((!InnerLoop.isOutermost() && "Inner loop should have a parent"
) ? static_cast<void> (0) : __assert_fail ("!InnerLoop.isOutermost() && \"Inner loop should have a parent\""
, "/build/llvm-toolchain-snapshot-12~++20210125100614+2cdb34efdac5/llvm/lib/Analysis/LoopNestAnalysis.cpp"
, 56, __PRETTY_FUNCTION__));
12
←
Assuming the condition is true
→
13
←
'?' condition is true
→
57 LLVM_DEBUG(dbgs() << "Checking whether loop '" << OuterLoop.getName()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("loopnest")) { dbgs() << "Checking whether loop '" <<
OuterLoop.getName() << "' and '" << InnerLoop.getName
() << "' are perfectly nested.\n"; } } while (false)
14
←
Assuming 'DebugFlag' is false
→
15
←
Loop condition is false. Exiting loop
→
58 << "' and '" << InnerLoop.getName()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("loopnest")) { dbgs() << "Checking whether loop '" <<
OuterLoop.getName() << "' and '" << InnerLoop.getName
() << "' are perfectly nested.\n"; } } while (false)
59 << "' are perfectly nested.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("loopnest")) { dbgs() << "Checking whether loop '" <<
OuterLoop.getName() << "' and '" << InnerLoop.getName
() << "' are perfectly nested.\n"; } } while (false);
60
61 // Determine whether the loops structure satisfies the following requirements:
62 // - the inner loop should be the outer loop's only child
63 // - the outer loop header should 'flow' into the inner loop preheader
64 // or jump around the inner loop to the outer loop latch
65 // - if the inner loop latch exits the inner loop, it should 'flow' into
66 // the outer loop latch.
67 if (!checkLoopsStructure(OuterLoop, InnerLoop, SE)) {
16
←
Calling 'checkLoopsStructure'
→
68 LLVM_DEBUG(dbgs() << "Not perfectly nested: invalid loop structure.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("loopnest")) { dbgs() << "Not perfectly nested: invalid loop structure.\n"
; } } while (false);
69 return false;
70 }
71
72 // Bail out if we cannot retrieve the outer loop bounds.
73 auto OuterLoopLB = OuterLoop.getBounds(SE);
74 if (OuterLoopLB == None) {
75 LLVM_DEBUG(dbgs() << "Cannot compute loop bounds of OuterLoop: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("loopnest")) { dbgs() << "Cannot compute loop bounds of OuterLoop: "
<< OuterLoop << "\n";; } } while (false)
76 << OuterLoop << "\n";)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("loopnest")) { dbgs() << "Cannot compute loop bounds of OuterLoop: "
<< OuterLoop << "\n";; } } while (false);
77 return false;
78 }
79
80 // Identify the outer loop latch comparison instruction.
81 const BasicBlock *Latch = OuterLoop.getLoopLatch();
82 assert(Latch && "Expecting a valid loop latch")((Latch && "Expecting a valid loop latch") ? static_cast
<void> (0) : __assert_fail ("Latch && \"Expecting a valid loop latch\""
, "/build/llvm-toolchain-snapshot-12~++20210125100614+2cdb34efdac5/llvm/lib/Analysis/LoopNestAnalysis.cpp"
, 82, __PRETTY_FUNCTION__));
83 const BranchInst *BI = dyn_cast<BranchInst>(Latch->getTerminator());
84 assert(BI && BI->isConditional() &&((BI && BI->isConditional() && "Expecting loop latch terminator to be a branch instruction"
) ? static_cast<void> (0) : __assert_fail ("BI && BI->isConditional() && \"Expecting loop latch terminator to be a branch instruction\""
, "/build/llvm-toolchain-snapshot-12~++20210125100614+2cdb34efdac5/llvm/lib/Analysis/LoopNestAnalysis.cpp"
, 85, __PRETTY_FUNCTION__))
85 "Expecting loop latch terminator to be a branch instruction")((BI && BI->isConditional() && "Expecting loop latch terminator to be a branch instruction"
) ? static_cast<void> (0) : __assert_fail ("BI && BI->isConditional() && \"Expecting loop latch terminator to be a branch instruction\""
, "/build/llvm-toolchain-snapshot-12~++20210125100614+2cdb34efdac5/llvm/lib/Analysis/LoopNestAnalysis.cpp"
, 85, __PRETTY_FUNCTION__));
86
87 const CmpInst *OuterLoopLatchCmp = dyn_cast<CmpInst>(BI->getCondition());
88 DEBUG_WITH_TYPE(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { if (OuterLoopLatchCmp) { dbgs() << "Outer loop latch compare instruction: "
<< *OuterLoopLatchCmp << "\n"; }; } } while (false
)
89 VerboseDebug, if (OuterLoopLatchCmp) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { if (OuterLoopLatchCmp) { dbgs() << "Outer loop latch compare instruction: "
<< *OuterLoopLatchCmp << "\n"; }; } } while (false
)
90 dbgs() << "Outer loop latch compare instruction: " << *OuterLoopLatchCmpdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { if (OuterLoopLatchCmp) { dbgs() << "Outer loop latch compare instruction: "
<< *OuterLoopLatchCmp << "\n"; }; } } while (false
)
91 << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { if (OuterLoopLatchCmp) { dbgs() << "Outer loop latch compare instruction: "
<< *OuterLoopLatchCmp << "\n"; }; } } while (false
)
92 })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { if (OuterLoopLatchCmp) { dbgs() << "Outer loop latch compare instruction: "
<< *OuterLoopLatchCmp << "\n"; }; } } while (false
);
93
94 // Identify the inner loop guard instruction.
95 BranchInst *InnerGuard = InnerLoop.getLoopGuardBranch();
96 const CmpInst *InnerLoopGuardCmp =
97 (InnerGuard) ? dyn_cast<CmpInst>(InnerGuard->getCondition()) : nullptr;
98
99 DEBUG_WITH_TYPE(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { if (InnerLoopGuardCmp) { dbgs() << "Inner loop guard compare instruction: "
<< *InnerLoopGuardCmp << "\n"; }; } } while (false
)
100 VerboseDebug, if (InnerLoopGuardCmp) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { if (InnerLoopGuardCmp) { dbgs() << "Inner loop guard compare instruction: "
<< *InnerLoopGuardCmp << "\n"; }; } } while (false
)
101 dbgs() << "Inner loop guard compare instruction: " << *InnerLoopGuardCmpdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { if (InnerLoopGuardCmp) { dbgs() << "Inner loop guard compare instruction: "
<< *InnerLoopGuardCmp << "\n"; }; } } while (false
)
102 << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { if (InnerLoopGuardCmp) { dbgs() << "Inner loop guard compare instruction: "
<< *InnerLoopGuardCmp << "\n"; }; } } while (false
)
103 })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { if (InnerLoopGuardCmp) { dbgs() << "Inner loop guard compare instruction: "
<< *InnerLoopGuardCmp << "\n"; }; } } while (false
);
104
105 // Determine whether instructions in a basic block are one of:
106 // - the inner loop guard comparison
107 // - the outer loop latch comparison
108 // - the outer loop induction variable increment
109 // - a phi node, a cast or a branch
110 auto containsOnlySafeInstructions = [&](const BasicBlock &BB) {
111 return llvm::all_of(BB, [&](const Instruction &I) {
112 bool isAllowed = isSafeToSpeculativelyExecute(&I) || isa<PHINode>(I) ||
113 isa<BranchInst>(I);
114 if (!isAllowed) {
115 DEBUG_WITH_TYPE(VerboseDebug, {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { { dbgs() << "Instruction: " << I
<< "\nin basic block: " << BB << " is considered unsafe.\n"
; }; } } while (false)
116 dbgs() << "Instruction: " << I << "\nin basic block: " << BBdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { { dbgs() << "Instruction: " << I
<< "\nin basic block: " << BB << " is considered unsafe.\n"
; }; } } while (false)
117 << " is considered unsafe.\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { { dbgs() << "Instruction: " << I
<< "\nin basic block: " << BB << " is considered unsafe.\n"
; }; } } while (false)
118 })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { { dbgs() << "Instruction: " << I
<< "\nin basic block: " << BB << " is considered unsafe.\n"
; }; } } while (false);
119 return false;
120 }
121
122 // The only binary instruction allowed is the outer loop step instruction,
123 // the only comparison instructions allowed are the inner loop guard
124 // compare instruction and the outer loop latch compare instruction.
125 if ((isa<BinaryOperator>(I) && &I != &OuterLoopLB->getStepInst()) ||
126 (isa<CmpInst>(I) && &I != OuterLoopLatchCmp &&
127 &I != InnerLoopGuardCmp)) {
128 DEBUG_WITH_TYPE(VerboseDebug, {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { { dbgs() << "Instruction: " << I
<< "\nin basic block:" << BB << "is unsafe.\n"
; }; } } while (false)
129 dbgs() << "Instruction: " << I << "\nin basic block:" << BBdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { { dbgs() << "Instruction: " << I
<< "\nin basic block:" << BB << "is unsafe.\n"
; }; } } while (false)
130 << "is unsafe.\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { { dbgs() << "Instruction: " << I
<< "\nin basic block:" << BB << "is unsafe.\n"
; }; } } while (false)
131 })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { { dbgs() << "Instruction: " << I
<< "\nin basic block:" << BB << "is unsafe.\n"
; }; } } while (false);
132 return false;
133 }
134 return true;
135 });
136 };
137
138 // Check the code surrounding the inner loop for instructions that are deemed
139 // unsafe.
140 const BasicBlock *OuterLoopHeader = OuterLoop.getHeader();
141 const BasicBlock *OuterLoopLatch = OuterLoop.getLoopLatch();
142 const BasicBlock *InnerLoopPreHeader = InnerLoop.getLoopPreheader();
143
144 if (!containsOnlySafeInstructions(*OuterLoopHeader) ||
145 !containsOnlySafeInstructions(*OuterLoopLatch) ||
146 (InnerLoopPreHeader != OuterLoopHeader &&
147 !containsOnlySafeInstructions(*InnerLoopPreHeader)) ||
148 !containsOnlySafeInstructions(*InnerLoop.getExitBlock())) {
149 LLVM_DEBUG(dbgs() << "Not perfectly nested: code surrounding inner loop is "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("loopnest")) { dbgs() << "Not perfectly nested: code surrounding inner loop is "
"unsafe\n";; } } while (false)
150 "unsafe\n";)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("loopnest")) { dbgs() << "Not perfectly nested: code surrounding inner loop is "
"unsafe\n";; } } while (false);
151 return false;
152 }
153
154 LLVM_DEBUG(dbgs() << "Loop '" << OuterLoop.getName() << "' and '"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("loopnest")) { dbgs() << "Loop '" << OuterLoop.getName
() << "' and '" << InnerLoop.getName() << "' are perfectly nested.\n"
; } } while (false)
155 << InnerLoop.getName() << "' are perfectly nested.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("loopnest")) { dbgs() << "Loop '" << OuterLoop.getName
() << "' and '" << InnerLoop.getName() << "' are perfectly nested.\n"
; } } while (false);
156
157 return true;
158}
159
160SmallVector<LoopVectorTy, 4>
161LoopNest::getPerfectLoops(ScalarEvolution &SE) const {
162 SmallVector<LoopVectorTy, 4> LV;
163 LoopVectorTy PerfectNest;
164
165 for (Loop *L : depth_first(const_cast<Loop *>(Loops.front()))) {
166 if (PerfectNest.empty())
167 PerfectNest.push_back(L);
168
169 auto &SubLoops = L->getSubLoops();
170 if (SubLoops.size() == 1 && arePerfectlyNested(*L, *SubLoops.front(), SE)) {
171 PerfectNest.push_back(SubLoops.front());
172 } else {
173 LV.push_back(PerfectNest);
174 PerfectNest.clear();
175 }
176 }
177
178 return LV;
179}
180
181unsigned LoopNest::getMaxPerfectDepth(const Loop &Root, ScalarEvolution &SE) {
182 LLVM_DEBUG(dbgs() << "Get maximum perfect depth of loop nest rooted by loop '"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("loopnest")) { dbgs() << "Get maximum perfect depth of loop nest rooted by loop '"
<< Root.getName() << "'\n"; } } while (false)
5
←
Assuming 'DebugFlag' is false
→
6
←
Loop condition is false. Exiting loop
→
183 << Root.getName() << "'\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("loopnest")) { dbgs() << "Get maximum perfect depth of loop nest rooted by loop '"
<< Root.getName() << "'\n"; } } while (false);
184
185 const Loop *CurrentLoop = &Root;
186 const auto *SubLoops = &CurrentLoop->getSubLoops();
187 unsigned CurrentDepth = 1;
188
189 while (SubLoops->size() == 1) {
7
←
Assuming the condition is true
→
8
←
Loop condition is true. Entering loop body
→
190 const Loop *InnerLoop = SubLoops->front();
191 if (!arePerfectlyNested(*CurrentLoop, *InnerLoop, SE)) {
9
←
Calling 'LoopNest::arePerfectlyNested'
→
192 LLVM_DEBUG({do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("loopnest")) { { dbgs() << "Not a perfect nest: loop '"
<< CurrentLoop->getName() << "' is not perfectly nested with loop '"
<< InnerLoop->getName() << "'\n"; }; } } while
(false)
193 dbgs() << "Not a perfect nest: loop '" << CurrentLoop->getName()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("loopnest")) { { dbgs() << "Not a perfect nest: loop '"
<< CurrentLoop->getName() << "' is not perfectly nested with loop '"
<< InnerLoop->getName() << "'\n"; }; } } while
(false)
194 << "' is not perfectly nested with loop '"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("loopnest")) { { dbgs() << "Not a perfect nest: loop '"
<< CurrentLoop->getName() << "' is not perfectly nested with loop '"
<< InnerLoop->getName() << "'\n"; }; } } while
(false)
195 << InnerLoop->getName() << "'\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("loopnest")) { { dbgs() << "Not a perfect nest: loop '"
<< CurrentLoop->getName() << "' is not perfectly nested with loop '"
<< InnerLoop->getName() << "'\n"; }; } } while
(false)
196 })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("loopnest")) { { dbgs() << "Not a perfect nest: loop '"
<< CurrentLoop->getName() << "' is not perfectly nested with loop '"
<< InnerLoop->getName() << "'\n"; }; } } while
(false);
197 break;
198 }
199
200 CurrentLoop = InnerLoop;
201 SubLoops = &CurrentLoop->getSubLoops();
202 ++CurrentDepth;
203 }
204
205 return CurrentDepth;
206}
207
208const BasicBlock &LoopNest::skipEmptyBlockUntil(const BasicBlock *From,
209 const BasicBlock *End) {
210 assert(From && "Expecting valid From")((From && "Expecting valid From") ? static_cast<void
> (0) : __assert_fail ("From && \"Expecting valid From\""
, "/build/llvm-toolchain-snapshot-12~++20210125100614+2cdb34efdac5/llvm/lib/Analysis/LoopNestAnalysis.cpp"
, 210, __PRETTY_FUNCTION__));
30
←
Assuming 'From' is non-null
→
31
←
'?' condition is true
→
211 assert(End && "Expecting valid End")((End && "Expecting valid End") ? static_cast<void
> (0) : __assert_fail ("End && \"Expecting valid End\""
, "/build/llvm-toolchain-snapshot-12~++20210125100614+2cdb34efdac5/llvm/lib/Analysis/LoopNestAnalysis.cpp"
, 211, __PRETTY_FUNCTION__));
32
←
Assuming 'End' is non-null
→
33
←
'?' condition is true
→
212
213 if (From
33.1
'From' is not equal to 'End'
33.1
'From' is not equal to 'End'
 == End || !From->getSingleSuccessor())
34
←
Assuming the condition is false
→
35
←
Taking false branch
→
214 return *From;
215
216 auto IsEmpty = [](const BasicBlock *BB) {
217 return (BB->getInstList().size() == 1);
218 };
219
220 // Visited is used to avoid running into an infinite loop.
221 SmallPtrSet<const BasicBlock *, 4> Visited;
222 const BasicBlock *BB = From->getSingleSuccessor();
223 const BasicBlock *PredBB = BB;
224 while (BB && BB != End && IsEmpty(BB) && !Visited.count(BB)) {
36
←
Assuming 'BB' is null
→
225 Visited.insert(BB);
226 PredBB = BB;
227 BB = BB->getSingleSuccessor();
228 }
229
230 return (BB
36.1
'BB' is not equal to 'End'
36.1
'BB' is not equal to 'End'
 == End) ? *End : *PredBB;
37
←
'?' condition is false
→
38
←
Returning null reference
231}
232
233static bool checkLoopsStructure(const Loop &OuterLoop, const Loop &InnerLoop,
234 ScalarEvolution &SE) {
235 // The inner loop must be the only outer loop's child.
236 if ((OuterLoop.getSubLoops().size() != 1) ||
17
←
Assuming the condition is false
→
19
←
Taking false branch
→
237 (InnerLoop.getParentLoop() != &OuterLoop))
18
←
Assuming the condition is false
→
238 return false;
239
240 // We expect loops in normal form which have a preheader, header, latch...
241 if (!OuterLoop.isLoopSimplifyForm() || !InnerLoop.isLoopSimplifyForm())
20
←
Assuming the condition is false
→
21
←
Assuming the condition is false
→
22
←
Taking false branch
→
242 return false;
243
244 const BasicBlock *OuterLoopHeader = OuterLoop.getHeader();
245 const BasicBlock *OuterLoopLatch = OuterLoop.getLoopLatch();
246 const BasicBlock *InnerLoopPreHeader = InnerLoop.getLoopPreheader();
247 const BasicBlock *InnerLoopLatch = InnerLoop.getLoopLatch();
248 const BasicBlock *InnerLoopExit = InnerLoop.getExitBlock();
249
250 // We expect rotated loops. The inner loop should have a single exit block.
251 if (OuterLoop.getExitingBlock() != OuterLoopLatch ||
23
←
Assuming the condition is false
→
26
←
Taking false branch
→
252 InnerLoop.getExitingBlock() != InnerLoopLatch || !InnerLoopExit)
24
←
Assuming the condition is false
→
25
←
Assuming 'InnerLoopExit' is non-null
→
253 return false;
254
255 // Returns whether the block `ExitBlock` contains at least one LCSSA Phi node.
256 auto ContainsLCSSAPhi = [](const BasicBlock &ExitBlock) {
257 return any_of(ExitBlock.phis(), [](const PHINode &PN) {
258 return PN.getNumIncomingValues() == 1;
259 });
260 };
261
262 // Returns whether the block `BB` qualifies for being an extra Phi block. The
263 // extra Phi block is the additional block inserted after the exit block of an
264 // "guarded" inner loop which contains "only" Phi nodes corresponding to the
265 // LCSSA Phi nodes in the exit block.
266 auto IsExtraPhiBlock = [&](const BasicBlock &BB) {
267 return BB.getFirstNonPHI() == BB.getTerminator() &&
268 all_of(BB.phis(), [&](const PHINode &PN) {
269 return all_of(PN.blocks(), [&](const BasicBlock *IncomingBlock) {
270 return IncomingBlock == InnerLoopExit ||
271 IncomingBlock == OuterLoopHeader;
272 });
273 });
274 };
275
276 const BasicBlock *ExtraPhiBlock = nullptr;
277 // Ensure the only branch that may exist between the loops is the inner loop
278 // guard.
279 if (OuterLoopHeader != InnerLoopPreHeader) {
27
←
Assuming 'OuterLoopHeader' is not equal to 'InnerLoopPreHeader'
→
28
←
Taking true branch
→
280 const BasicBlock &SingleSucc =
281 LoopNest::skipEmptyBlockUntil(OuterLoopHeader, InnerLoopPreHeader);
29
←
Calling 'LoopNest::skipEmptyBlockUntil'
→
282
283 // no conditional branch present
284 if (&SingleSucc != InnerLoopPreHeader) {
285 const BranchInst *BI = dyn_cast<BranchInst>(SingleSucc.getTerminator());
286
287 if (!BI || BI != InnerLoop.getLoopGuardBranch())
288 return false;
289
290 bool InnerLoopExitContainsLCSSA = ContainsLCSSAPhi(*InnerLoopExit);
291
292 // The successors of the inner loop guard should be the inner loop
293 // preheader or the outer loop latch possibly through empty blocks.
294 for (const BasicBlock *Succ : BI->successors()) {
295 const BasicBlock *PotentialInnerPreHeader = Succ;
296 const BasicBlock *PotentialOuterLatch = Succ;
297
298 // Ensure the inner loop guard successor is empty before skipping
299 // blocks.
300 if (Succ->getInstList().size() == 1) {
301 PotentialInnerPreHeader =
302 &LoopNest::skipEmptyBlockUntil(Succ, InnerLoopPreHeader);
303 PotentialOuterLatch =
304 &LoopNest::skipEmptyBlockUntil(Succ, OuterLoopLatch);
305 }
306
307 if (PotentialInnerPreHeader == InnerLoopPreHeader)
308 continue;
309 if (PotentialOuterLatch == OuterLoopLatch)
310 continue;
311
312 // If `InnerLoopExit` contains LCSSA Phi instructions, additional block
313 // may be inserted before the `OuterLoopLatch` to which `BI` jumps. The
314 // loops are still considered perfectly nested if the extra block only
315 // contains Phi instructions from InnerLoopExit and OuterLoopHeader.
316 if (InnerLoopExitContainsLCSSA && IsExtraPhiBlock(*Succ) &&
317 Succ->getSingleSuccessor() == OuterLoopLatch) {
318 // Points to the extra block so that we can reference it later in the
319 // final check. We can also conclude that the inner loop is
320 // guarded and there exists LCSSA Phi node in the exit block later if
321 // we see a non-null `ExtraPhiBlock`.
322 ExtraPhiBlock = Succ;
323 continue;
324 }
325
326 DEBUG_WITH_TYPE(VerboseDebug, {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { { dbgs() << "Inner loop guard successor "
<< Succ->getName() << " doesn't lead to inner loop preheader or "
"outer loop latch.\n"; }; } } while (false)
327 dbgs() << "Inner loop guard successor " << Succ->getName()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { { dbgs() << "Inner loop guard successor "
<< Succ->getName() << " doesn't lead to inner loop preheader or "
"outer loop latch.\n"; }; } } while (false)
328 << " doesn't lead to inner loop preheader or "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { { dbgs() << "Inner loop guard successor "
<< Succ->getName() << " doesn't lead to inner loop preheader or "
"outer loop latch.\n"; }; } } while (false)
329 "outer loop latch.\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { { dbgs() << "Inner loop guard successor "
<< Succ->getName() << " doesn't lead to inner loop preheader or "
"outer loop latch.\n"; }; } } while (false)
330 })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { { dbgs() << "Inner loop guard successor "
<< Succ->getName() << " doesn't lead to inner loop preheader or "
"outer loop latch.\n"; }; } } while (false);
331 return false;
332 }
333 }
334 }
335
336 // Ensure the inner loop exit block lead to the outer loop latch possibly
337 // through empty blocks.
338 const BasicBlock &SuccInner =
339 LoopNest::skipEmptyBlockUntil(InnerLoop.getExitBlock(), OuterLoopLatch);
340 if (&SuccInner != OuterLoopLatch && &SuccInner != ExtraPhiBlock) {
341 DEBUG_WITH_TYPE(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { dbgs() << "Inner loop exit block " <<
*InnerLoopExit << " does not directly lead to the outer loop latch.\n"
;; } } while (false)
342 VerboseDebug,do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { dbgs() << "Inner loop exit block " <<
*InnerLoopExit << " does not directly lead to the outer loop latch.\n"
;; } } while (false)
343 dbgs() << "Inner loop exit block " << *InnerLoopExitdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { dbgs() << "Inner loop exit block " <<
*InnerLoopExit << " does not directly lead to the outer loop latch.\n"
;; } } while (false)
344 << " does not directly lead to the outer loop latch.\n";)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
(VerboseDebug)) { dbgs() << "Inner loop exit block " <<
*InnerLoopExit << " does not directly lead to the outer loop latch.\n"
;; } } while (false);
345 return false;
346 }
347
348 return true;
349}
350
351AnalysisKey LoopNestAnalysis::Key;
352
353raw_ostream &llvm::operator<<(raw_ostream &OS, const LoopNest &LN) {
354 OS << "IsPerfect=";
355 if (LN.getMaxPerfectDepth() == LN.getNestDepth())
356 OS << "true";
357 else
358 OS << "false";
359 OS << ", Depth=" << LN.getNestDepth();
360 OS << ", OutermostLoop: " << LN.getOutermostLoop().getName();
361 OS << ", Loops: ( ";
362 for (const Loop *L : LN.getLoops())
363 OS << L->getName() << " ";
364 OS << ")";
365
366 return OS;
367}
368
369//===----------------------------------------------------------------------===//
370// LoopNestPrinterPass implementation
371//
372
373PreservedAnalyses LoopNestPrinterPass::run(Loop &L, LoopAnalysisManager &AM,
374 LoopStandardAnalysisResults &AR,
375 LPMUpdater &U) {
376 if (auto LN = LoopNest::getLoopNest(L, AR.SE))
1
Calling 'LoopNest::getLoopNest'
→
377 OS << *LN << "\n";
378
379 return PreservedAnalyses::all();
380}
←

/usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/bits/unique_ptr.h

1// unique_ptr implementation -*- C++ -*-
2
3// Copyright (C) 2008-2016 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
39namespace std _GLIBCXX_VISIBILITY(default)__attribute__ ((__visibility__ ("default")))
40{
41_GLIBCXX_BEGIN_NAMESPACE_VERSION
42
43 /**
44 * @addtogroup pointer_abstractions
45 * @{
46 */
47
48#if _GLIBCXX_USE_DEPRECATED1
49 template<typename> class auto_ptr;
50#endif
51
52 /// Primary template of default_delete, used by unique_ptr
53 template<typename _Tp>
54 struct default_delete
55 {
56 /// Default constructor
57 constexpr default_delete() noexcept = default;
58
59 /** @brief Converting constructor.
60 *
61 * Allows conversion from a deleter for arrays of another type, @p _Up,
62 * only if @p _Up* is convertible to @p _Tp*.
63 */
64 template<typename _Up, typename = typename
65 enable_if<is_convertible<_Up*, _Tp*>::value>::type>
66 default_delete(const default_delete<_Up>&) noexcept { }
67
68 /// Calls @c delete @p __ptr
69 void
70 operator()(_Tp* __ptr) const
71 {
72 static_assert(!is_void<_Tp>::value,
73 "can't delete pointer to incomplete type");
74 static_assert(sizeof(_Tp)>0,
75 "can't delete pointer to incomplete type");
76 delete __ptr;
77 }
78 };
79
80 // _GLIBCXX_RESOLVE_LIB_DEFECTS
81 // DR 740 - omit specialization for array objects with a compile time length
82 /// Specialization for arrays, default_delete.
83 template<typename _Tp>
84 struct default_delete<_Tp[]>
85 {
86 public:
87 /// Default constructor
88 constexpr default_delete() noexcept = default;
89
90 /** @brief Converting constructor.
91 *
92 * Allows conversion from a deleter for arrays of another type, such as
93 * a const-qualified version of @p _Tp.
94 *
95 * Conversions from types derived from @c _Tp are not allowed because
96 * it is unsafe to @c delete[] an array of derived types through a
97 * pointer to the base type.
98 */
99 template<typename _Up, typename = typename
100 enable_if<is_convertible<_Up(*)[], _Tp(*)[]>::value>::type>
101 default_delete(const default_delete<_Up[]>&) noexcept { }
102
103 /// Calls @c delete[] @p __ptr
104 template<typename _Up>
105 typename enable_if<is_convertible<_Up(*)[], _Tp(*)[]>::value>::type
106 operator()(_Up* __ptr) const
107 {
108 static_assert(sizeof(_Tp)>0,
109 "can't delete pointer to incomplete type");
110 delete [] __ptr;
111 }
112 };
113
114 /// 20.7.1.2 unique_ptr for single objects.
115 template <typename _Tp, typename _Dp = default_delete<_Tp> >
116 class unique_ptr
117 {
118 // use SFINAE to determine whether _Del::pointer exists
119 class _Pointer
120 {
121 template<typename _Up>
122 static typename _Up::pointer __test(typename _Up::pointer*);
123
124 template<typename _Up>
125 static _Tp* __test(...);
126
127 typedef typename remove_reference<_Dp>::type _Del;
128
129 public:
130 typedef decltype(__test<_Del>(0)) type;
131 };
132
133 typedef std::tuple<typename _Pointer::type, _Dp> __tuple_type;
134 __tuple_type _M_t;
135
136 public:
137 typedef typename _Pointer::type pointer;
138 typedef _Tp element_type;
139 typedef _Dp deleter_type;
140
141
142 // helper template for detecting a safe conversion from another
143 // unique_ptr
144 template<typename _Up, typename _Ep>
145 using __safe_conversion_up = __and_<
146 is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>,
147 __not_<is_array<_Up>>,
148 __or_<__and_<is_reference<deleter_type>,
149 is_same<deleter_type, _Ep>>,
150 __and_<__not_<is_reference<deleter_type>>,
151 is_convertible<_Ep, deleter_type>>
152 >
153 >;
154
155 // Constructors.
156
157 /// Default constructor, creates a unique_ptr that owns nothing.
158 constexpr unique_ptr() noexcept
159 : _M_t()
160 { static_assert(!is_pointer<deleter_type>::value,
161 "constructed with null function pointer deleter"); }
162
163 /** Takes ownership of a pointer.
164 *
165 * @param __p A pointer to an object of @c element_type
166 *
167 * The deleter will be value-initialized.
168 */
169 explicit
170 unique_ptr(pointer __p) noexcept
171 : _M_t()
172 {
173 std::get<0>(_M_t) = __p;
174 static_assert(!is_pointer<deleter_type>::value,
175 "constructed with null function pointer deleter");
176 }
177
178 /** Takes ownership of a pointer.
179 *
180 * @param __p A pointer to an object of @c element_type
181 * @param __d A reference to a deleter.
182 *
183 * The deleter will be initialized with @p __d
184 */
185 unique_ptr(pointer __p,
186 typename conditional<is_reference<deleter_type>::value,
187 deleter_type, const deleter_type&>::type __d) noexcept
188 : _M_t(__p, __d) { }
189
190 /** Takes ownership of a pointer.
191 *
192 * @param __p A pointer to an object of @c element_type
193 * @param __d An rvalue reference to a deleter.
194 *
195 * The deleter will be initialized with @p std::move(__d)
196 */
197 unique_ptr(pointer __p,
198 typename remove_reference<deleter_type>::type&& __d) noexcept
199 : _M_t(std::move(__p), std::move(__d))
200 { static_assert(!std::is_reference<deleter_type>::value,
201 "rvalue deleter bound to reference"); }
202
203 /// Creates a unique_ptr that owns nothing.
204 constexpr unique_ptr(nullptr_t) noexcept : unique_ptr() { }
205
206 // Move constructors.
207
208 /// Move constructor.
209 unique_ptr(unique_ptr&& __u) noexcept
210 : _M_t(__u.release(), std::forward<deleter_type>(__u.get_deleter())) { }
211
212 /** @brief Converting constructor from another type
213 *
214 * Requires that the pointer owned by @p __u is convertible to the
215 * type of pointer owned by this object, @p __u does not own an array,
216 * and @p __u has a compatible deleter type.
217 */
218 template<typename _Up, typename _Ep, typename = _Require<
219 __safe_conversion_up<_Up, _Ep>,
220 typename conditional<is_reference<_Dp>::value,
221 is_same<_Ep, _Dp>,
222 is_convertible<_Ep, _Dp>>::type>>
223 unique_ptr(unique_ptr<_Up, _Ep>&& __u) noexcept
224 : _M_t(__u.release(), std::forward<_Ep>(__u.get_deleter()))
225 { }
226
227#if _GLIBCXX_USE_DEPRECATED1
228 /// Converting constructor from @c auto_ptr
229 template<typename _Up, typename = _Require<
230 is_convertible<_Up*, _Tp*>, is_same<_Dp, default_delete<_Tp>>>>
231 unique_ptr(auto_ptr<_Up>&& __u) noexcept;
232#endif
233
234 /// Destructor, invokes the deleter if the stored pointer is not null.
235 ~unique_ptr() noexcept
236 {
237 auto& __ptr = std::get<0>(_M_t);
238 if (__ptr != nullptr)
239 get_deleter()(__ptr);
240 __ptr = pointer();
241 }
242
243 // Assignment.
244
245 /** @brief Move assignment operator.
246 *
247 * @param __u The object to transfer ownership from.
248 *
249 * Invokes the deleter first if this object owns a pointer.
250 */
251 unique_ptr&
252 operator=(unique_ptr&& __u) noexcept
253 {
254 reset(__u.release());
255 get_deleter() = std::forward<deleter_type>(__u.get_deleter());
256 return *this;
257 }
258
259 /** @brief Assignment from another type.
260 *
261 * @param __u The object to transfer ownership from, which owns a
262 * convertible pointer to a non-array object.
263 *
264 * Invokes the deleter first if this object owns a pointer.
265 */
266 template<typename _Up, typename _Ep>
267 typename enable_if< __and_<
268 __safe_conversion_up<_Up, _Ep>,
269 is_assignable<deleter_type&, _Ep&&>
270 >::value,
271 unique_ptr&>::type
272 operator=(unique_ptr<_Up, _Ep>&& __u) noexcept
273 {
274 reset(__u.release());
275 get_deleter() = std::forward<_Ep>(__u.get_deleter());
276 return *this;
277 }
278
279 /// Reset the %unique_ptr to empty, invoking the deleter if necessary.
280 unique_ptr&
281 operator=(nullptr_t) noexcept
282 {
283 reset();
284 return *this;
285 }
286
287 // Observers.
288
289 /// Dereference the stored pointer.
290 typename add_lvalue_reference<element_type>::type
291 operator*() const
292 {
293 __glibcxx_assert(get() != pointer());
294 return *get();
295 }
296
297 /// Return the stored pointer.
298 pointer
299 operator->() const noexcept
300 {
301 _GLIBCXX_DEBUG_PEDASSERT(get() != pointer());
302 return get();
303 }
304
305 /// Return the stored pointer.
306 pointer
307 get() const noexcept
308 { return std::get<0>(_M_t); }
309
310 /// Return a reference to the stored deleter.
311 deleter_type&
312 get_deleter() noexcept
313 { return std::get<1>(_M_t); }
314
315 /// Return a reference to the stored deleter.
316 const deleter_type&
317 get_deleter() const noexcept
318 { return std::get<1>(_M_t); }
319
320 /// Return @c true if the stored pointer is not null.
321 explicit operator bool() const noexcept
322 { return get() == pointer() ? false : true; }
323
324 // Modifiers.
325
326 /// Release ownership of any stored pointer.
327 pointer
328 release() noexcept
329 {
330 pointer __p = get();
331 std::get<0>(_M_t) = pointer();
332 return __p;
333 }
334
335 /** @brief Replace the stored pointer.
336 *
337 * @param __p The new pointer to store.
338 *
339 * The deleter will be invoked if a pointer is already owned.
340 */
341 void
342 reset(pointer __p = pointer()) noexcept
343 {
344 using std::swap;
345 swap(std::get<0>(_M_t), __p);
346 if (__p != pointer())
347 get_deleter()(__p);
348 }
349
350 /// Exchange the pointer and deleter with another object.
351 void
352 swap(unique_ptr& __u) noexcept
353 {
354 using std::swap;
355 swap(_M_t, __u._M_t);
356 }
357
358 // Disable copy from lvalue.
359 unique_ptr(const unique_ptr&) = delete;
360 unique_ptr& operator=(const unique_ptr&) = delete;
361 };
362
363 /// 20.7.1.3 unique_ptr for array objects with a runtime length
364 // [unique.ptr.runtime]
365 // _GLIBCXX_RESOLVE_LIB_DEFECTS
366 // DR 740 - omit specialization for array objects with a compile time length
367 template<typename _Tp, typename _Dp>
368 class unique_ptr<_Tp[], _Dp>
369 {
370 // use SFINAE to determine whether _Del::pointer exists
371 class _Pointer
372 {
373 template<typename _Up>
374 static typename _Up::pointer __test(typename _Up::pointer*);
375
376 template<typename _Up>
377 static _Tp* __test(...);
378
379 typedef typename remove_reference<_Dp>::type _Del;
380
381 public:
382 typedef decltype(__test<_Del>(0)) type;
383 };
384
385 typedef std::tuple<typename _Pointer::type, _Dp> __tuple_type;
386 __tuple_type _M_t;
387
388 template<typename _Up>
389 using __remove_cv = typename remove_cv<_Up>::type;
390
391 // like is_base_of<_Tp, _Up> but false if unqualified types are the same
392 template<typename _Up>
393 using __is_derived_Tp
394 = __and_< is_base_of<_Tp, _Up>,
395 __not_<is_same<__remove_cv<_Tp>, __remove_cv<_Up>>> >;
396
397
398 public:
399 typedef typename _Pointer::type pointer;
400 typedef _Tp element_type;
401 typedef _Dp deleter_type;
402
403 // helper template for detecting a safe conversion from another
404 // unique_ptr
405 template<typename _Up, typename _Ep,
406 typename _Up_up = unique_ptr<_Up, _Ep>,
407 typename _Up_element_type = typename _Up_up::element_type>
408 using __safe_conversion_up = __and_<
409 is_array<_Up>,
410 is_same<pointer, element_type*>,
411 is_same<typename _Up_up::pointer, _Up_element_type*>,
412 is_convertible<_Up_element_type(*)[], element_type(*)[]>,
413 __or_<__and_<is_reference<deleter_type>, is_same<deleter_type, _Ep>>,
414 __and_<__not_<is_reference<deleter_type>>,
415 is_convertible<_Ep, deleter_type>>>
416 >;
417
418 // helper template for detecting a safe conversion from a raw pointer
419 template<typename _Up>
420 using __safe_conversion_raw = __and_<
421 __or_<__or_<is_same<_Up, pointer>,
422 is_same<_Up, nullptr_t>>,
423 __and_<is_pointer<_Up>,
424 is_same<pointer, element_type*>,
425 is_convertible<
426 typename remove_pointer<_Up>::type(*)[],
427 element_type(*)[]>
428 >
429 >
430 >;
431
432 // Constructors.
433
434 /// Default constructor, creates a unique_ptr that owns nothing.
435 constexpr unique_ptr() noexcept
436 : _M_t()
437 { static_assert(!std::is_pointer<deleter_type>::value,
438 "constructed with null function pointer deleter"); }
439
440 /** Takes ownership of a pointer.
441 *
442 * @param __p A pointer to an array of a type safely convertible
443 * to an array of @c element_type
444 *
445 * The deleter will be value-initialized.
446 */
447 template<typename _Up,
448 typename = typename enable_if<
449 __safe_conversion_raw<_Up>::value, bool>::type>
450 explicit
451 unique_ptr(_Up __p) noexcept
452 : _M_t(__p, deleter_type())
453 { static_assert(!is_pointer<deleter_type>::value,
454 "constructed with null function pointer deleter"); }
455
456 /** Takes ownership of a pointer.
457 *
458 * @param __p A pointer to an array of a type safely convertible
459 * to an array of @c element_type
460 * @param __d A reference to a deleter.
461 *
462 * The deleter will be initialized with @p __d
463 */
464 template<typename _Up,
465 typename = typename enable_if<
466 __safe_conversion_raw<_Up>::value, bool>::type>
467 unique_ptr(_Up __p,
468 typename conditional<is_reference<deleter_type>::value,
469 deleter_type, const deleter_type&>::type __d) noexcept
470 : _M_t(__p, __d) { }
471
472 /** Takes ownership of a pointer.
473 *
474 * @param __p A pointer to an array of a type safely convertible
475 * to an array of @c element_type
476 * @param __d A reference to a deleter.
477 *
478 * The deleter will be initialized with @p std::move(__d)
479 */
480 template<typename _Up,
481 typename = typename enable_if<
482 __safe_conversion_raw<_Up>::value, bool>::type>
483 unique_ptr(_Up __p, typename
484 remove_reference<deleter_type>::type&& __d) noexcept
485 : _M_t(std::move(__p), std::move(__d))
486 { static_assert(!is_reference<deleter_type>::value,
487 "rvalue deleter bound to reference"); }
488
489 /// Move constructor.
490 unique_ptr(unique_ptr&& __u) noexcept
491 : _M_t(__u.release(), std::forward<deleter_type>(__u.get_deleter())) { }
492
493 /// Creates a unique_ptr that owns nothing.
494 constexpr unique_ptr(nullptr_t) noexcept : unique_ptr() { }
495
496 template<typename _Up, typename _Ep,
497 typename = _Require<__safe_conversion_up<_Up, _Ep>>>
498 unique_ptr(unique_ptr<_Up, _Ep>&& __u) noexcept
499 : _M_t(__u.release(), std::forward<_Ep>(__u.get_deleter()))
500 { }
501
502 /// Destructor, invokes the deleter if the stored pointer is not null.
503 ~unique_ptr()
504 {
505 auto& __ptr = std::get<0>(_M_t);
506 if (__ptr != nullptr)
507 get_deleter()(__ptr);
508 __ptr = pointer();
509 }
510
511 // Assignment.
512
513 /** @brief Move assignment operator.
514 *
515 * @param __u The object to transfer ownership from.
516 *
517 * Invokes the deleter first if this object owns a pointer.
518 */
519 unique_ptr&
520 operator=(unique_ptr&& __u) noexcept
521 {
522 reset(__u.release());
523 get_deleter() = std::forward<deleter_type>(__u.get_deleter());
524 return *this;
525 }
526
527 /** @brief Assignment from another type.
528 *
529 * @param __u The object to transfer ownership from, which owns a
530 * convertible pointer to an array object.
531 *
532 * Invokes the deleter first if this object owns a pointer.
533 */
534 template<typename _Up, typename _Ep>
535 typename
536 enable_if<__and_<__safe_conversion_up<_Up, _Ep>,
537 is_assignable<deleter_type&, _Ep&&>
538 >::value,
539 unique_ptr&>::type
540 operator=(unique_ptr<_Up, _Ep>&& __u) noexcept
541 {
542 reset(__u.release());
543 get_deleter() = std::forward<_Ep>(__u.get_deleter());
544 return *this;
545 }
546
547 /// Reset the %unique_ptr to empty, invoking the deleter if necessary.
548 unique_ptr&
549 operator=(nullptr_t) noexcept
550 {
551 reset();
552 return *this;
553 }
554
555 // Observers.
556
557 /// Access an element of owned array.
558 typename std::add_lvalue_reference<element_type>::type
559 operator[](size_t __i) const
560 {
561 __glibcxx_assert(get() != pointer());
562 return get()[__i];
563 }
564
565 /// Return the stored pointer.
566 pointer
567 get() const noexcept
568 { return std::get<0>(_M_t); }
569
570 /// Return a reference to the stored deleter.
571 deleter_type&
572 get_deleter() noexcept
573 { return std::get<1>(_M_t); }
574
575 /// Return a reference to the stored deleter.
576 const deleter_type&
577 get_deleter() const noexcept
578 { return std::get<1>(_M_t); }
579
580 /// Return @c true if the stored pointer is not null.
581 explicit operator bool() const noexcept
582 { return get() == pointer() ? false : true; }
583
584 // Modifiers.
585
586 /// Release ownership of any stored pointer.
587 pointer
588 release() noexcept
589 {
590 pointer __p = get();
591 std::get<0>(_M_t) = pointer();
592 return __p;
593 }
594
595 /** @brief Replace the stored pointer.
596 *
597 * @param __p The new pointer to store.
598 *
599 * The deleter will be invoked if a pointer is already owned.
600 */
601 template <typename _Up,
602 typename = _Require<
603 __or_<is_same<_Up, pointer>,
604 __and_<is_same<pointer, element_type*>,
605 is_pointer<_Up>,
606 is_convertible<
607 typename remove_pointer<_Up>::type(*)[],
608 element_type(*)[]
609 >
610 >
611 >
612 >>
613 void
614 reset(_Up __p) noexcept
615 {
616 pointer __ptr = __p;
617 using std::swap;
618 swap(std::get<0>(_M_t), __ptr);
619 if (__ptr != nullptr)
620 get_deleter()(__ptr);
621 }
622
623 void reset(nullptr_t = nullptr) noexcept
624 {
625 reset(pointer());
626 }
627
628 /// Exchange the pointer and deleter with another object.
629 void
630 swap(unique_ptr& __u) noexcept
631 {
632 using std::swap;
633 swap(_M_t, __u._M_t);
634 }
635
636 // Disable copy from lvalue.
637 unique_ptr(const unique_ptr&) = delete;
638 unique_ptr& operator=(const unique_ptr&) = delete;
639 };
640
641 template<typename _Tp, typename _Dp>
642 inline void
643 swap(unique_ptr<_Tp, _Dp>& __x,
644 unique_ptr<_Tp, _Dp>& __y) noexcept
645 { __x.swap(__y); }
646
647 template<typename _Tp, typename _Dp,
648 typename _Up, typename _Ep>
649 inline bool
650 operator==(const unique_ptr<_Tp, _Dp>& __x,
651 const unique_ptr<_Up, _Ep>& __y)
652 { return __x.get() == __y.get(); }
653
654 template<typename _Tp, typename _Dp>
655 inline bool
656 operator==(const unique_ptr<_Tp, _Dp>& __x, nullptr_t) noexcept
657 { return !__x; }
658
659 template<typename _Tp, typename _Dp>
660 inline bool
661 operator==(nullptr_t, const unique_ptr<_Tp, _Dp>& __x) noexcept
662 { return !__x; }
663
664 template<typename _Tp, typename _Dp,
665 typename _Up, typename _Ep>
666 inline bool
667 operator!=(const unique_ptr<_Tp, _Dp>& __x,
668 const unique_ptr<_Up, _Ep>& __y)
669 { return __x.get() != __y.get(); }
670
671 template<typename _Tp, typename _Dp>
672 inline bool
673 operator!=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t) noexcept
674 { return (bool)__x; }
675
676 template<typename _Tp, typename _Dp>
677 inline bool
678 operator!=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x) noexcept
679 { return (bool)__x; }
680
681 template<typename _Tp, typename _Dp,
682 typename _Up, typename _Ep>
683 inline bool
684 operator<(const unique_ptr<_Tp, _Dp>& __x,
685 const unique_ptr<_Up, _Ep>& __y)
686 {
687 typedef typename
688 std::common_type<typename unique_ptr<_Tp, _Dp>::pointer,
689 typename unique_ptr<_Up, _Ep>::pointer>::type _CT;
690 return std::less<_CT>()(__x.get(), __y.get());
691 }
692
693 template<typename _Tp, typename _Dp>
694 inline bool
695 operator<(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
696 { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(__x.get(),
697 nullptr); }
698
699 template<typename _Tp, typename _Dp>
700 inline bool
701 operator<(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
702 { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(nullptr,
703 __x.get()); }
704
705 template<typename _Tp, typename _Dp,
706 typename _Up, typename _Ep>
707 inline bool
708 operator<=(const unique_ptr<_Tp, _Dp>& __x,
709 const unique_ptr<_Up, _Ep>& __y)
710 { return !(__y < __x); }
711
712 template<typename _Tp, typename _Dp>
713 inline bool
714 operator<=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
715 { return !(nullptr < __x); }
716
717 template<typename _Tp, typename _Dp>
718 inline bool
719 operator<=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
720 { return !(__x < nullptr); }
721
722 template<typename _Tp, typename _Dp,
723 typename _Up, typename _Ep>
724 inline bool
725 operator>(const unique_ptr<_Tp, _Dp>& __x,
726 const unique_ptr<_Up, _Ep>& __y)
727 { return (__y < __x); }
728
729 template<typename _Tp, typename _Dp>
730 inline bool
731 operator>(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
732 { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(nullptr,
733 __x.get()); }
734
735 template<typename _Tp, typename _Dp>
736 inline bool
737 operator>(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
738 { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(__x.get(),
739 nullptr); }
740
741 template<typename _Tp, typename _Dp,
742 typename _Up, typename _Ep>
743 inline bool
744 operator>=(const unique_ptr<_Tp, _Dp>& __x,
745 const unique_ptr<_Up, _Ep>& __y)
746 { return !(__x < __y); }
747
748 template<typename _Tp, typename _Dp>
749 inline bool
750 operator>=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
751 { return !(__x < nullptr); }
752
753 template<typename _Tp, typename _Dp>
754 inline bool
755 operator>=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
756 { return !(nullptr < __x); }
757
758 /// std::hash specialization for unique_ptr.
759 template<typename _Tp, typename _Dp>
760 struct hash<unique_ptr<_Tp, _Dp>>
761 : public __hash_base<size_t, unique_ptr<_Tp, _Dp>>
762 {
763 size_t
764 operator()(const unique_ptr<_Tp, _Dp>& __u) const noexcept
765 {
766 typedef unique_ptr<_Tp, _Dp> _UP;
767 return std::hash<typename _UP::pointer>()(__u.get());
768 }
769 };
770
771#if __cplusplus201402L > 201103L
772
773#define __cpp_lib_make_unique201304 201304
774
775 template<typename _Tp>
776 struct _MakeUniq
777 { typedef unique_ptr<_Tp> __single_object; };
778
779 template<typename _Tp>
780 struct _MakeUniq<_Tp[]>
781 { typedef unique_ptr<_Tp[]> __array; };
782
783 template<typename _Tp, size_t _Bound>
784 struct _MakeUniq<_Tp[_Bound]>
785 { struct __invalid_type { }; };
786
787 /// std::make_unique for single objects
788 template<typename _Tp, typename... _Args>
789 inline typename _MakeUniq<_Tp>::__single_object
790 make_unique(_Args&&... __args)
791 { return unique_ptr<_Tp>(new _Tp(std::forward<_Args>(__args)...)); }
3
←
Calling constructor for 'LoopNest'
→
792
793 /// std::make_unique for arrays of unknown bound
794 template<typename _Tp>
795 inline typename _MakeUniq<_Tp>::__array
796 make_unique(size_t __num)
797 { return unique_ptr<_Tp>(new remove_extent_t<_Tp>[__num]()); }
798
799 /// Disable std::make_unique for arrays of known bound
800 template<typename _Tp, typename... _Args>
801 inline typename _MakeUniq<_Tp>::__invalid_type
802 make_unique(_Args&&...) = delete;
803#endif
804
805 // @} group pointer_abstractions
806
807_GLIBCXX_END_NAMESPACE_VERSION
808} // namespace
809
810#endif /* _UNIQUE_PTR_H */