Bug Summary

File:llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp
Warning:line 180, column 8
Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name GCOVProfiling.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 -mthread-model posix -mframe-pointer=none -fmath-errno -fno-rounding-math -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-10/lib/clang/10.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/build-llvm/lib/Transforms/Instrumentation -I /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/Transforms/Instrumentation -I /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/build-llvm/include -I /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/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-10/lib/clang/10.0.0/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-10~+201911111502510600c19528f1809/build-llvm/lib/Transforms/Instrumentation -fdebug-prefix-map=/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809=. -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -fobjc-runtime=gcc -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -o /tmp/scan-build-2019-12-09-002921-48462-1 -x c++ /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp
1//===- GCOVProfiling.cpp - Insert edge counters for gcov profiling --------===//
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 pass implements GCOV-style profiling. When this pass is run it emits
10// "gcno" files next to the existing source, and instruments the code that runs
11// to records the edges between blocks that run and emit a complementary "gcda"
12// file on exit.
13//
14//===----------------------------------------------------------------------===//
15
16#include "llvm/ADT/DenseMap.h"
17#include "llvm/ADT/Hashing.h"
18#include "llvm/ADT/STLExtras.h"
19#include "llvm/ADT/Sequence.h"
20#include "llvm/ADT/Statistic.h"
21#include "llvm/ADT/StringExtras.h"
22#include "llvm/ADT/StringMap.h"
23#include "llvm/Analysis/EHPersonalities.h"
24#include "llvm/Analysis/TargetLibraryInfo.h"
25#include "llvm/IR/CFG.h"
26#include "llvm/IR/DebugInfo.h"
27#include "llvm/IR/DebugLoc.h"
28#include "llvm/IR/IRBuilder.h"
29#include "llvm/IR/InstIterator.h"
30#include "llvm/IR/Instructions.h"
31#include "llvm/IR/IntrinsicInst.h"
32#include "llvm/IR/Module.h"
33#include "llvm/Pass.h"
34#include "llvm/Support/CommandLine.h"
35#include "llvm/Support/Debug.h"
36#include "llvm/Support/FileSystem.h"
37#include "llvm/Support/Path.h"
38#include "llvm/Support/Regex.h"
39#include "llvm/Support/raw_ostream.h"
40#include "llvm/Transforms/Instrumentation.h"
41#include "llvm/Transforms/Instrumentation/GCOVProfiler.h"
42#include "llvm/Transforms/Utils/ModuleUtils.h"
43#include <algorithm>
44#include <memory>
45#include <string>
46#include <utility>
47using namespace llvm;
48
49#define DEBUG_TYPE"insert-gcov-profiling" "insert-gcov-profiling"
50
51static cl::opt<std::string>
52DefaultGCOVVersion("default-gcov-version", cl::init("402*"), cl::Hidden,
53 cl::ValueRequired);
54static cl::opt<bool> DefaultExitBlockBeforeBody("gcov-exit-block-before-body",
55 cl::init(false), cl::Hidden);
56
57GCOVOptions GCOVOptions::getDefault() {
58 GCOVOptions Options;
59 Options.EmitNotes = true;
60 Options.EmitData = true;
61 Options.UseCfgChecksum = false;
62 Options.NoRedZone = false;
63 Options.FunctionNamesInData = true;
64 Options.ExitBlockBeforeBody = DefaultExitBlockBeforeBody;
65
66 if (DefaultGCOVVersion.size() != 4) {
67 llvm::report_fatal_error(std::string("Invalid -default-gcov-version: ") +
68 DefaultGCOVVersion);
69 }
70 memcpy(Options.Version, DefaultGCOVVersion.c_str(), 4);
71 return Options;
72}
73
74namespace {
75class GCOVFunction;
76
77class GCOVProfiler {
78public:
79 GCOVProfiler() : GCOVProfiler(GCOVOptions::getDefault()) {}
80 GCOVProfiler(const GCOVOptions &Opts) : Options(Opts) {
81 assert((Options.EmitNotes || Options.EmitData) &&(((Options.EmitNotes || Options.EmitData) && "GCOVProfiler asked to do nothing?"
) ? static_cast<void> (0) : __assert_fail ("(Options.EmitNotes || Options.EmitData) && \"GCOVProfiler asked to do nothing?\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp"
, 82, __PRETTY_FUNCTION__))
82 "GCOVProfiler asked to do nothing?")(((Options.EmitNotes || Options.EmitData) && "GCOVProfiler asked to do nothing?"
) ? static_cast<void> (0) : __assert_fail ("(Options.EmitNotes || Options.EmitData) && \"GCOVProfiler asked to do nothing?\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp"
, 82, __PRETTY_FUNCTION__))
;
83 ReversedVersion[0] = Options.Version[3];
84 ReversedVersion[1] = Options.Version[2];
85 ReversedVersion[2] = Options.Version[1];
86 ReversedVersion[3] = Options.Version[0];
87 ReversedVersion[4] = '\0';
88 }
89 bool
90 runOnModule(Module &M,
91 std::function<const TargetLibraryInfo &(Function &F)> GetTLI);
92
93private:
94 // Create the .gcno files for the Module based on DebugInfo.
95 void emitProfileNotes();
96
97 // Modify the program to track transitions along edges and call into the
98 // profiling runtime to emit .gcda files when run.
99 bool emitProfileArcs();
100
101 bool isFunctionInstrumented(const Function &F);
102 std::vector<Regex> createRegexesFromString(StringRef RegexesStr);
103 static bool doesFilenameMatchARegex(StringRef Filename,
104 std::vector<Regex> &Regexes);
105
106 // Get pointers to the functions in the runtime library.
107 FunctionCallee getStartFileFunc(const TargetLibraryInfo *TLI);
108 FunctionCallee getEmitFunctionFunc(const TargetLibraryInfo *TLI);
109 FunctionCallee getEmitArcsFunc(const TargetLibraryInfo *TLI);
110 FunctionCallee getSummaryInfoFunc();
111 FunctionCallee getEndFileFunc();
112
113 // Add the function to write out all our counters to the global destructor
114 // list.
115 Function *
116 insertCounterWriteout(ArrayRef<std::pair<GlobalVariable *, MDNode *>>);
117 Function *insertFlush(ArrayRef<std::pair<GlobalVariable *, MDNode *>>);
118
119 void AddFlushBeforeForkAndExec();
120
121 enum class GCovFileType { GCNO, GCDA };
122 std::string mangleName(const DICompileUnit *CU, GCovFileType FileType);
123
124 GCOVOptions Options;
125
126 // Reversed, NUL-terminated copy of Options.Version.
127 char ReversedVersion[5];
128 // Checksum, produced by hash of EdgeDestinations
129 SmallVector<uint32_t, 4> FileChecksums;
130
131 Module *M;
132 std::function<const TargetLibraryInfo &(Function &F)> GetTLI;
133 LLVMContext *Ctx;
134 SmallVector<std::unique_ptr<GCOVFunction>, 16> Funcs;
135 std::vector<Regex> FilterRe;
136 std::vector<Regex> ExcludeRe;
137 StringMap<bool> InstrumentedFiles;
138};
139
140class GCOVProfilerLegacyPass : public ModulePass {
141public:
142 static char ID;
143 GCOVProfilerLegacyPass()
144 : GCOVProfilerLegacyPass(GCOVOptions::getDefault()) {}
145 GCOVProfilerLegacyPass(const GCOVOptions &Opts)
146 : ModulePass(ID), Profiler(Opts) {
147 initializeGCOVProfilerLegacyPassPass(*PassRegistry::getPassRegistry());
148 }
149 StringRef getPassName() const override { return "GCOV Profiler"; }
150
151 bool runOnModule(Module &M) override {
152 return Profiler.runOnModule(M, [this](Function &F) -> TargetLibraryInfo & {
153 return getAnalysis<TargetLibraryInfoWrapperPass>().getTLI(F);
154 });
155 }
156
157 void getAnalysisUsage(AnalysisUsage &AU) const override {
158 AU.addRequired<TargetLibraryInfoWrapperPass>();
159 }
160
161private:
162 GCOVProfiler Profiler;
163};
164}
165
166char GCOVProfilerLegacyPass::ID = 0;
167INITIALIZE_PASS_BEGIN(static void *initializeGCOVProfilerLegacyPassPassOnce(PassRegistry
&Registry) {
168 GCOVProfilerLegacyPass, "insert-gcov-profiling",static void *initializeGCOVProfilerLegacyPassPassOnce(PassRegistry
&Registry) {
169 "Insert instrumentation for GCOV profiling", false, false)static void *initializeGCOVProfilerLegacyPassPassOnce(PassRegistry
&Registry) {
170INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass)initializeTargetLibraryInfoWrapperPassPass(Registry);
171INITIALIZE_PASS_END(PassInfo *PI = new PassInfo( "Insert instrumentation for GCOV profiling"
, "insert-gcov-profiling", &GCOVProfilerLegacyPass::ID, PassInfo
::NormalCtor_t(callDefaultCtor<GCOVProfilerLegacyPass>)
, false, false); Registry.registerPass(*PI, true); return PI;
} static llvm::once_flag InitializeGCOVProfilerLegacyPassPassFlag
; void llvm::initializeGCOVProfilerLegacyPassPass(PassRegistry
&Registry) { llvm::call_once(InitializeGCOVProfilerLegacyPassPassFlag
, initializeGCOVProfilerLegacyPassPassOnce, std::ref(Registry
)); }
172 GCOVProfilerLegacyPass, "insert-gcov-profiling",PassInfo *PI = new PassInfo( "Insert instrumentation for GCOV profiling"
, "insert-gcov-profiling", &GCOVProfilerLegacyPass::ID, PassInfo
::NormalCtor_t(callDefaultCtor<GCOVProfilerLegacyPass>)
, false, false); Registry.registerPass(*PI, true); return PI;
} static llvm::once_flag InitializeGCOVProfilerLegacyPassPassFlag
; void llvm::initializeGCOVProfilerLegacyPassPass(PassRegistry
&Registry) { llvm::call_once(InitializeGCOVProfilerLegacyPassPassFlag
, initializeGCOVProfilerLegacyPassPassOnce, std::ref(Registry
)); }
173 "Insert instrumentation for GCOV profiling", false, false)PassInfo *PI = new PassInfo( "Insert instrumentation for GCOV profiling"
, "insert-gcov-profiling", &GCOVProfilerLegacyPass::ID, PassInfo
::NormalCtor_t(callDefaultCtor<GCOVProfilerLegacyPass>)
, false, false); Registry.registerPass(*PI, true); return PI;
} static llvm::once_flag InitializeGCOVProfilerLegacyPassPassFlag
; void llvm::initializeGCOVProfilerLegacyPassPass(PassRegistry
&Registry) { llvm::call_once(InitializeGCOVProfilerLegacyPassPassFlag
, initializeGCOVProfilerLegacyPassPassOnce, std::ref(Registry
)); }
174
175ModulePass *llvm::createGCOVProfilerPass(const GCOVOptions &Options) {
176 return new GCOVProfilerLegacyPass(Options);
177}
178
179static StringRef getFunctionName(const DISubprogram *SP) {
180 if (!SP->getLinkageName().empty())
29
Called C++ object pointer is null
181 return SP->getLinkageName();
182 return SP->getName();
183}
184
185/// Extract a filename for a DISubprogram.
186///
187/// Prefer relative paths in the coverage notes. Clang also may split
188/// up absolute paths into a directory and filename component. When
189/// the relative path doesn't exist, reconstruct the absolute path.
190static SmallString<128> getFilename(const DISubprogram *SP) {
191 SmallString<128> Path;
192 StringRef RelPath = SP->getFilename();
193 if (sys::fs::exists(RelPath))
194 Path = RelPath;
195 else
196 sys::path::append(Path, SP->getDirectory(), SP->getFilename());
197 return Path;
198}
199
200namespace {
201 class GCOVRecord {
202 protected:
203 static const char *const LinesTag;
204 static const char *const FunctionTag;
205 static const char *const BlockTag;
206 static const char *const EdgeTag;
207
208 GCOVRecord() = default;
209
210 void writeBytes(const char *Bytes, int Size) {
211 os->write(Bytes, Size);
212 }
213
214 void write(uint32_t i) {
215 writeBytes(reinterpret_cast<char*>(&i), 4);
216 }
217
218 // Returns the length measured in 4-byte blocks that will be used to
219 // represent this string in a GCOV file
220 static unsigned lengthOfGCOVString(StringRef s) {
221 // A GCOV string is a length, followed by a NUL, then between 0 and 3 NULs
222 // padding out to the next 4-byte word. The length is measured in 4-byte
223 // words including padding, not bytes of actual string.
224 return (s.size() / 4) + 1;
225 }
226
227 void writeGCOVString(StringRef s) {
228 uint32_t Len = lengthOfGCOVString(s);
229 write(Len);
230 writeBytes(s.data(), s.size());
231
232 // Write 1 to 4 bytes of NUL padding.
233 assert((unsigned)(4 - (s.size() % 4)) > 0)(((unsigned)(4 - (s.size() % 4)) > 0) ? static_cast<void
> (0) : __assert_fail ("(unsigned)(4 - (s.size() % 4)) > 0"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp"
, 233, __PRETTY_FUNCTION__))
;
234 assert((unsigned)(4 - (s.size() % 4)) <= 4)(((unsigned)(4 - (s.size() % 4)) <= 4) ? static_cast<void
> (0) : __assert_fail ("(unsigned)(4 - (s.size() % 4)) <= 4"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp"
, 234, __PRETTY_FUNCTION__))
;
235 writeBytes("\0\0\0\0", 4 - (s.size() % 4));
236 }
237
238 raw_ostream *os;
239 };
240 const char *const GCOVRecord::LinesTag = "\0\0\x45\x01";
241 const char *const GCOVRecord::FunctionTag = "\0\0\0\1";
242 const char *const GCOVRecord::BlockTag = "\0\0\x41\x01";
243 const char *const GCOVRecord::EdgeTag = "\0\0\x43\x01";
244
245 class GCOVFunction;
246 class GCOVBlock;
247
248 // Constructed only by requesting it from a GCOVBlock, this object stores a
249 // list of line numbers and a single filename, representing lines that belong
250 // to the block.
251 class GCOVLines : public GCOVRecord {
252 public:
253 void addLine(uint32_t Line) {
254 assert(Line != 0 && "Line zero is not a valid real line number.")((Line != 0 && "Line zero is not a valid real line number."
) ? static_cast<void> (0) : __assert_fail ("Line != 0 && \"Line zero is not a valid real line number.\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp"
, 254, __PRETTY_FUNCTION__))
;
255 Lines.push_back(Line);
256 }
257
258 uint32_t length() const {
259 // Here 2 = 1 for string length + 1 for '0' id#.
260 return lengthOfGCOVString(Filename) + 2 + Lines.size();
261 }
262
263 void writeOut() {
264 write(0);
265 writeGCOVString(Filename);
266 for (int i = 0, e = Lines.size(); i != e; ++i)
267 write(Lines[i]);
268 }
269
270 GCOVLines(StringRef F, raw_ostream *os)
271 : Filename(F) {
272 this->os = os;
273 }
274
275 private:
276 std::string Filename;
277 SmallVector<uint32_t, 32> Lines;
278 };
279
280
281 // Represent a basic block in GCOV. Each block has a unique number in the
282 // function, number of lines belonging to each block, and a set of edges to
283 // other blocks.
284 class GCOVBlock : public GCOVRecord {
285 public:
286 GCOVLines &getFile(StringRef Filename) {
287 return LinesByFile.try_emplace(Filename, Filename, os).first->second;
288 }
289
290 void addEdge(GCOVBlock &Successor) {
291 OutEdges.push_back(&Successor);
292 }
293
294 void writeOut() {
295 uint32_t Len = 3;
296 SmallVector<StringMapEntry<GCOVLines> *, 32> SortedLinesByFile;
297 for (auto &I : LinesByFile) {
298 Len += I.second.length();
299 SortedLinesByFile.push_back(&I);
300 }
301
302 writeBytes(LinesTag, 4);
303 write(Len);
304 write(Number);
305
306 llvm::sort(SortedLinesByFile, [](StringMapEntry<GCOVLines> *LHS,
307 StringMapEntry<GCOVLines> *RHS) {
308 return LHS->getKey() < RHS->getKey();
309 });
310 for (auto &I : SortedLinesByFile)
311 I->getValue().writeOut();
312 write(0);
313 write(0);
314 }
315
316 GCOVBlock(const GCOVBlock &RHS) : GCOVRecord(RHS), Number(RHS.Number) {
317 // Only allow copy before edges and lines have been added. After that,
318 // there are inter-block pointers (eg: edges) that won't take kindly to
319 // blocks being copied or moved around.
320 assert(LinesByFile.empty())((LinesByFile.empty()) ? static_cast<void> (0) : __assert_fail
("LinesByFile.empty()", "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp"
, 320, __PRETTY_FUNCTION__))
;
321 assert(OutEdges.empty())((OutEdges.empty()) ? static_cast<void> (0) : __assert_fail
("OutEdges.empty()", "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp"
, 321, __PRETTY_FUNCTION__))
;
322 }
323
324 private:
325 friend class GCOVFunction;
326
327 GCOVBlock(uint32_t Number, raw_ostream *os)
328 : Number(Number) {
329 this->os = os;
330 }
331
332 uint32_t Number;
333 StringMap<GCOVLines> LinesByFile;
334 SmallVector<GCOVBlock *, 4> OutEdges;
335 };
336
337 // A function has a unique identifier, a checksum (we leave as zero) and a
338 // set of blocks and a map of edges between blocks. This is the only GCOV
339 // object users can construct, the blocks and lines will be rooted here.
340 class GCOVFunction : public GCOVRecord {
341 public:
342 GCOVFunction(const DISubprogram *SP, Function *F, raw_ostream *os,
343 uint32_t Ident, bool UseCfgChecksum, bool ExitBlockBeforeBody)
344 : SP(SP), Ident(Ident), UseCfgChecksum(UseCfgChecksum), CfgChecksum(0),
345 ReturnBlock(1, os) {
346 this->os = os;
347
348 LLVM_DEBUG(dbgs() << "Function: " << getFunctionName(SP) << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("insert-gcov-profiling")) { dbgs() << "Function: " <<
getFunctionName(SP) << "\n"; } } while (false)
;
349
350 uint32_t i = 0;
351 for (auto &BB : *F) {
352 // Skip index 1 if it's assigned to the ReturnBlock.
353 if (i == 1 && ExitBlockBeforeBody)
354 ++i;
355 Blocks.insert(std::make_pair(&BB, GCOVBlock(i++, os)));
356 }
357 if (!ExitBlockBeforeBody)
358 ReturnBlock.Number = i;
359
360 std::string FunctionNameAndLine;
361 raw_string_ostream FNLOS(FunctionNameAndLine);
362 FNLOS << getFunctionName(SP) << SP->getLine();
363 FNLOS.flush();
364 FuncChecksum = hash_value(FunctionNameAndLine);
365 }
366
367 GCOVBlock &getBlock(BasicBlock *BB) {
368 return Blocks.find(BB)->second;
369 }
370
371 GCOVBlock &getReturnBlock() {
372 return ReturnBlock;
373 }
374
375 std::string getEdgeDestinations() {
376 std::string EdgeDestinations;
377 raw_string_ostream EDOS(EdgeDestinations);
378 Function *F = Blocks.begin()->first->getParent();
379 for (BasicBlock &I : *F) {
380 GCOVBlock &Block = getBlock(&I);
381 for (int i = 0, e = Block.OutEdges.size(); i != e; ++i)
382 EDOS << Block.OutEdges[i]->Number;
383 }
384 return EdgeDestinations;
385 }
386
387 uint32_t getFuncChecksum() {
388 return FuncChecksum;
389 }
390
391 void setCfgChecksum(uint32_t Checksum) {
392 CfgChecksum = Checksum;
393 }
394
395 void writeOut() {
396 writeBytes(FunctionTag, 4);
397 SmallString<128> Filename = getFilename(SP);
398 uint32_t BlockLen = 1 + 1 + 1 + lengthOfGCOVString(getFunctionName(SP)) +
399 1 + lengthOfGCOVString(Filename) + 1;
400 if (UseCfgChecksum)
401 ++BlockLen;
402 write(BlockLen);
403 write(Ident);
404 write(FuncChecksum);
405 if (UseCfgChecksum)
406 write(CfgChecksum);
407 writeGCOVString(getFunctionName(SP));
408 writeGCOVString(Filename);
409 write(SP->getLine());
410
411 // Emit count of blocks.
412 writeBytes(BlockTag, 4);
413 write(Blocks.size() + 1);
414 for (int i = 0, e = Blocks.size() + 1; i != e; ++i) {
415 write(0); // No flags on our blocks.
416 }
417 LLVM_DEBUG(dbgs() << Blocks.size() << " blocks.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("insert-gcov-profiling")) { dbgs() << Blocks.size() <<
" blocks.\n"; } } while (false)
;
418
419 // Emit edges between blocks.
420 if (Blocks.empty()) return;
421 Function *F = Blocks.begin()->first->getParent();
422 for (BasicBlock &I : *F) {
423 GCOVBlock &Block = getBlock(&I);
424 if (Block.OutEdges.empty()) continue;
425
426 writeBytes(EdgeTag, 4);
427 write(Block.OutEdges.size() * 2 + 1);
428 write(Block.Number);
429 for (int i = 0, e = Block.OutEdges.size(); i != e; ++i) {
430 LLVM_DEBUG(dbgs() << Block.Number << " -> "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("insert-gcov-profiling")) { dbgs() << Block.Number <<
" -> " << Block.OutEdges[i]->Number << "\n"
; } } while (false)
431 << Block.OutEdges[i]->Number << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("insert-gcov-profiling")) { dbgs() << Block.Number <<
" -> " << Block.OutEdges[i]->Number << "\n"
; } } while (false)
;
432 write(Block.OutEdges[i]->Number);
433 write(0); // no flags
434 }
435 }
436
437 // Emit lines for each block.
438 for (BasicBlock &I : *F)
439 getBlock(&I).writeOut();
440 }
441
442 private:
443 const DISubprogram *SP;
444 uint32_t Ident;
445 uint32_t FuncChecksum;
446 bool UseCfgChecksum;
447 uint32_t CfgChecksum;
448 DenseMap<BasicBlock *, GCOVBlock> Blocks;
449 GCOVBlock ReturnBlock;
450 };
451}
452
453// RegexesStr is a string containing differents regex separated by a semi-colon.
454// For example "foo\..*$;bar\..*$".
455std::vector<Regex> GCOVProfiler::createRegexesFromString(StringRef RegexesStr) {
456 std::vector<Regex> Regexes;
457 while (!RegexesStr.empty()) {
458 std::pair<StringRef, StringRef> HeadTail = RegexesStr.split(';');
459 if (!HeadTail.first.empty()) {
460 Regex Re(HeadTail.first);
461 std::string Err;
462 if (!Re.isValid(Err)) {
463 Ctx->emitError(Twine("Regex ") + HeadTail.first +
464 " is not valid: " + Err);
465 }
466 Regexes.emplace_back(std::move(Re));
467 }
468 RegexesStr = HeadTail.second;
469 }
470 return Regexes;
471}
472
473bool GCOVProfiler::doesFilenameMatchARegex(StringRef Filename,
474 std::vector<Regex> &Regexes) {
475 for (Regex &Re : Regexes) {
476 if (Re.match(Filename)) {
477 return true;
478 }
479 }
480 return false;
481}
482
483bool GCOVProfiler::isFunctionInstrumented(const Function &F) {
484 if (FilterRe.empty() && ExcludeRe.empty()) {
485 return true;
486 }
487 SmallString<128> Filename = getFilename(F.getSubprogram());
488 auto It = InstrumentedFiles.find(Filename);
489 if (It != InstrumentedFiles.end()) {
490 return It->second;
491 }
492
493 SmallString<256> RealPath;
494 StringRef RealFilename;
495
496 // Path can be
497 // /usr/lib/gcc/x86_64-linux-gnu/8/../../../../include/c++/8/bits/*.h so for
498 // such a case we must get the real_path.
499 if (sys::fs::real_path(Filename, RealPath)) {
500 // real_path can fail with path like "foo.c".
501 RealFilename = Filename;
502 } else {
503 RealFilename = RealPath;
504 }
505
506 bool ShouldInstrument;
507 if (FilterRe.empty()) {
508 ShouldInstrument = !doesFilenameMatchARegex(RealFilename, ExcludeRe);
509 } else if (ExcludeRe.empty()) {
510 ShouldInstrument = doesFilenameMatchARegex(RealFilename, FilterRe);
511 } else {
512 ShouldInstrument = doesFilenameMatchARegex(RealFilename, FilterRe) &&
513 !doesFilenameMatchARegex(RealFilename, ExcludeRe);
514 }
515 InstrumentedFiles[Filename] = ShouldInstrument;
516 return ShouldInstrument;
517}
518
519std::string GCOVProfiler::mangleName(const DICompileUnit *CU,
520 GCovFileType OutputType) {
521 bool Notes = OutputType == GCovFileType::GCNO;
522
523 if (NamedMDNode *GCov = M->getNamedMetadata("llvm.gcov")) {
524 for (int i = 0, e = GCov->getNumOperands(); i != e; ++i) {
525 MDNode *N = GCov->getOperand(i);
526 bool ThreeElement = N->getNumOperands() == 3;
527 if (!ThreeElement && N->getNumOperands() != 2)
528 continue;
529 if (dyn_cast<MDNode>(N->getOperand(ThreeElement ? 2 : 1)) != CU)
530 continue;
531
532 if (ThreeElement) {
533 // These nodes have no mangling to apply, it's stored mangled in the
534 // bitcode.
535 MDString *NotesFile = dyn_cast<MDString>(N->getOperand(0));
536 MDString *DataFile = dyn_cast<MDString>(N->getOperand(1));
537 if (!NotesFile || !DataFile)
538 continue;
539 return Notes ? NotesFile->getString() : DataFile->getString();
540 }
541
542 MDString *GCovFile = dyn_cast<MDString>(N->getOperand(0));
543 if (!GCovFile)
544 continue;
545
546 SmallString<128> Filename = GCovFile->getString();
547 sys::path::replace_extension(Filename, Notes ? "gcno" : "gcda");
548 return Filename.str();
549 }
550 }
551
552 SmallString<128> Filename = CU->getFilename();
553 sys::path::replace_extension(Filename, Notes ? "gcno" : "gcda");
554 StringRef FName = sys::path::filename(Filename);
555 SmallString<128> CurPath;
556 if (sys::fs::current_path(CurPath)) return FName;
557 sys::path::append(CurPath, FName);
558 return CurPath.str();
559}
560
561bool GCOVProfiler::runOnModule(
562 Module &M, std::function<const TargetLibraryInfo &(Function &F)> GetTLI) {
563 this->M = &M;
564 this->GetTLI = std::move(GetTLI);
565 Ctx = &M.getContext();
566
567 AddFlushBeforeForkAndExec();
568
569 FilterRe = createRegexesFromString(Options.Filter);
570 ExcludeRe = createRegexesFromString(Options.Exclude);
571
572 if (Options.EmitNotes) emitProfileNotes();
2
Assuming field 'EmitNotes' is false
3
Taking false branch
573 if (Options.EmitData) return emitProfileArcs();
4
Assuming field 'EmitData' is true
5
Taking true branch
6
Calling 'GCOVProfiler::emitProfileArcs'
574 return false;
575}
576
577PreservedAnalyses GCOVProfilerPass::run(Module &M,
578 ModuleAnalysisManager &AM) {
579
580 GCOVProfiler Profiler(GCOVOpts);
581 FunctionAnalysisManager &FAM =
582 AM.getResult<FunctionAnalysisManagerModuleProxy>(M).getManager();
583
584 if (!Profiler.runOnModule(M, [&](Function &F) -> TargetLibraryInfo & {
1
Calling 'GCOVProfiler::runOnModule'
585 return FAM.getResult<TargetLibraryAnalysis>(F);
586 }))
587 return PreservedAnalyses::all();
588
589 return PreservedAnalyses::none();
590}
591
592static bool functionHasLines(Function &F) {
593 // Check whether this function actually has any source lines. Not only
594 // do these waste space, they also can crash gcov.
595 for (auto &BB : F) {
596 for (auto &I : BB) {
597 // Debug intrinsic locations correspond to the location of the
598 // declaration, not necessarily any statements or expressions.
599 if (isa<DbgInfoIntrinsic>(&I)) continue;
600
601 const DebugLoc &Loc = I.getDebugLoc();
602 if (!Loc)
603 continue;
604
605 // Artificial lines such as calls to the global constructors.
606 if (Loc.getLine() == 0) continue;
607
608 return true;
609 }
610 }
611 return false;
612}
613
614static bool isUsingScopeBasedEH(Function &F) {
615 if (!F.hasPersonalityFn()) return false;
616
617 EHPersonality Personality = classifyEHPersonality(F.getPersonalityFn());
618 return isScopedEHPersonality(Personality);
619}
620
621static bool shouldKeepInEntry(BasicBlock::iterator It) {
622 if (isa<AllocaInst>(*It)) return true;
623 if (isa<DbgInfoIntrinsic>(*It)) return true;
624 if (auto *II = dyn_cast<IntrinsicInst>(It)) {
625 if (II->getIntrinsicID() == llvm::Intrinsic::localescape) return true;
626 }
627
628 return false;
629}
630
631void GCOVProfiler::AddFlushBeforeForkAndExec() {
632 SmallVector<Instruction *, 2> ForkAndExecs;
633 for (auto &F : M->functions()) {
634 auto *TLI = &GetTLI(F);
635 for (auto &I : instructions(F)) {
636 if (CallInst *CI = dyn_cast<CallInst>(&I)) {
637 if (Function *Callee = CI->getCalledFunction()) {
638 LibFunc LF;
639 if (TLI->getLibFunc(*Callee, LF) &&
640 (LF == LibFunc_fork || LF == LibFunc_execl ||
641 LF == LibFunc_execle || LF == LibFunc_execlp ||
642 LF == LibFunc_execv || LF == LibFunc_execvp ||
643 LF == LibFunc_execve || LF == LibFunc_execvpe ||
644 LF == LibFunc_execvP)) {
645 ForkAndExecs.push_back(&I);
646 }
647 }
648 }
649 }
650 }
651
652 // We need to split the block after the fork/exec call
653 // because else the counters for the lines after will be
654 // the same as before the call.
655 for (auto I : ForkAndExecs) {
656 IRBuilder<> Builder(I);
657 FunctionType *FTy = FunctionType::get(Builder.getVoidTy(), {}, false);
658 FunctionCallee GCOVFlush = M->getOrInsertFunction("__gcov_flush", FTy);
659 Builder.CreateCall(GCOVFlush);
660 I->getParent()->splitBasicBlock(I);
661 }
662}
663
664void GCOVProfiler::emitProfileNotes() {
665 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
666 if (!CU_Nodes) return;
667
668 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
669 // Each compile unit gets its own .gcno file. This means that whether we run
670 // this pass over the original .o's as they're produced, or run it after
671 // LTO, we'll generate the same .gcno files.
672
673 auto *CU = cast<DICompileUnit>(CU_Nodes->getOperand(i));
674
675 // Skip module skeleton (and module) CUs.
676 if (CU->getDWOId())
677 continue;
678
679 std::error_code EC;
680 raw_fd_ostream out(mangleName(CU, GCovFileType::GCNO), EC,
681 sys::fs::OF_None);
682 if (EC) {
683 Ctx->emitError(Twine("failed to open coverage notes file for writing: ") +
684 EC.message());
685 continue;
686 }
687
688 std::string EdgeDestinations;
689
690 unsigned FunctionIdent = 0;
691 for (auto &F : M->functions()) {
692 DISubprogram *SP = F.getSubprogram();
693 if (!SP) continue;
694 if (!functionHasLines(F) || !isFunctionInstrumented(F))
695 continue;
696 // TODO: Functions using scope-based EH are currently not supported.
697 if (isUsingScopeBasedEH(F)) continue;
698
699 // gcov expects every function to start with an entry block that has a
700 // single successor, so split the entry block to make sure of that.
701 BasicBlock &EntryBlock = F.getEntryBlock();
702 BasicBlock::iterator It = EntryBlock.begin();
703 while (shouldKeepInEntry(It))
704 ++It;
705 EntryBlock.splitBasicBlock(It);
706
707 Funcs.push_back(std::make_unique<GCOVFunction>(SP, &F, &out, FunctionIdent++,
708 Options.UseCfgChecksum,
709 Options.ExitBlockBeforeBody));
710 GCOVFunction &Func = *Funcs.back();
711
712 // Add the function line number to the lines of the entry block
713 // to have a counter for the function definition.
714 uint32_t Line = SP->getLine();
715 auto Filename = getFilename(SP);
716 Func.getBlock(&EntryBlock).getFile(Filename).addLine(Line);
717
718 for (auto &BB : F) {
719 GCOVBlock &Block = Func.getBlock(&BB);
720 Instruction *TI = BB.getTerminator();
721 if (int successors = TI->getNumSuccessors()) {
722 for (int i = 0; i != successors; ++i) {
723 Block.addEdge(Func.getBlock(TI->getSuccessor(i)));
724 }
725 } else if (isa<ReturnInst>(TI)) {
726 Block.addEdge(Func.getReturnBlock());
727 }
728
729 for (auto &I : BB) {
730 // Debug intrinsic locations correspond to the location of the
731 // declaration, not necessarily any statements or expressions.
732 if (isa<DbgInfoIntrinsic>(&I)) continue;
733
734 const DebugLoc &Loc = I.getDebugLoc();
735 if (!Loc)
736 continue;
737
738 // Artificial lines such as calls to the global constructors.
739 if (Loc.getLine() == 0 || Loc.isImplicitCode())
740 continue;
741
742 if (Line == Loc.getLine()) continue;
743 Line = Loc.getLine();
744 if (SP != getDISubprogram(Loc.getScope()))
745 continue;
746
747 GCOVLines &Lines = Block.getFile(Filename);
748 Lines.addLine(Loc.getLine());
749 }
750 Line = 0;
751 }
752 EdgeDestinations += Func.getEdgeDestinations();
753 }
754
755 FileChecksums.push_back(hash_value(EdgeDestinations));
756 out.write("oncg", 4);
757 out.write(ReversedVersion, 4);
758 out.write(reinterpret_cast<char*>(&FileChecksums.back()), 4);
759
760 for (auto &Func : Funcs) {
761 Func->setCfgChecksum(FileChecksums.back());
762 Func->writeOut();
763 }
764
765 out.write("\0\0\0\0\0\0\0\0", 8); // EOF
766 out.close();
767 }
768}
769
770bool GCOVProfiler::emitProfileArcs() {
771 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
772 if (!CU_Nodes) return false;
7
Assuming 'CU_Nodes' is non-null
8
Taking false branch
773
774 bool Result = false;
775 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
9
Assuming 'i' is not equal to 'e'
10
Loop condition is true. Entering loop body
776 SmallVector<std::pair<GlobalVariable *, MDNode *>, 8> CountersBySP;
777 for (auto &F : M->functions()) {
778 DISubprogram *SP = F.getSubprogram();
779 if (!SP) continue;
780 if (!functionHasLines(F) || !isFunctionInstrumented(F))
781 continue;
782 // TODO: Functions using scope-based EH are currently not supported.
783 if (isUsingScopeBasedEH(F)) continue;
784 if (!Result) Result = true;
785
786 DenseMap<std::pair<BasicBlock *, BasicBlock *>, unsigned> EdgeToCounter;
787 unsigned Edges = 0;
788 for (auto &BB : F) {
789 Instruction *TI = BB.getTerminator();
790 if (isa<ReturnInst>(TI)) {
791 EdgeToCounter[{&BB, nullptr}] = Edges++;
792 } else {
793 for (BasicBlock *Succ : successors(TI)) {
794 EdgeToCounter[{&BB, Succ}] = Edges++;
795 }
796 }
797 }
798
799 ArrayType *CounterTy =
800 ArrayType::get(Type::getInt64Ty(*Ctx), Edges);
801 GlobalVariable *Counters =
802 new GlobalVariable(*M, CounterTy, false,
803 GlobalValue::InternalLinkage,
804 Constant::getNullValue(CounterTy),
805 "__llvm_gcov_ctr");
806 CountersBySP.push_back(std::make_pair(Counters, SP));
807
808 // If a BB has several predecessors, use a PHINode to select
809 // the correct counter.
810 for (auto &BB : F) {
811 const unsigned EdgeCount =
812 std::distance(pred_begin(&BB), pred_end(&BB));
813 if (EdgeCount) {
814 // The phi node must be at the begin of the BB.
815 IRBuilder<> BuilderForPhi(&*BB.begin());
816 Type *Int64PtrTy = Type::getInt64PtrTy(*Ctx);
817 PHINode *Phi = BuilderForPhi.CreatePHI(Int64PtrTy, EdgeCount);
818 for (BasicBlock *Pred : predecessors(&BB)) {
819 auto It = EdgeToCounter.find({Pred, &BB});
820 assert(It != EdgeToCounter.end())((It != EdgeToCounter.end()) ? static_cast<void> (0) : __assert_fail
("It != EdgeToCounter.end()", "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp"
, 820, __PRETTY_FUNCTION__))
;
821 const unsigned Edge = It->second;
822 Value *EdgeCounter = BuilderForPhi.CreateConstInBoundsGEP2_64(
823 Counters->getValueType(), Counters, 0, Edge);
824 Phi->addIncoming(EdgeCounter, Pred);
825 }
826
827 // Skip phis, landingpads.
828 IRBuilder<> Builder(&*BB.getFirstInsertionPt());
829 Value *Count = Builder.CreateLoad(Builder.getInt64Ty(), Phi);
830 Count = Builder.CreateAdd(Count, Builder.getInt64(1));
831 Builder.CreateStore(Count, Phi);
832
833 Instruction *TI = BB.getTerminator();
834 if (isa<ReturnInst>(TI)) {
835 auto It = EdgeToCounter.find({&BB, nullptr});
836 assert(It != EdgeToCounter.end())((It != EdgeToCounter.end()) ? static_cast<void> (0) : __assert_fail
("It != EdgeToCounter.end()", "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp"
, 836, __PRETTY_FUNCTION__))
;
837 const unsigned Edge = It->second;
838 Value *Counter = Builder.CreateConstInBoundsGEP2_64(
839 Counters->getValueType(), Counters, 0, Edge);
840 Value *Count = Builder.CreateLoad(Builder.getInt64Ty(), Counter);
841 Count = Builder.CreateAdd(Count, Builder.getInt64(1));
842 Builder.CreateStore(Count, Counter);
843 }
844 }
845 }
846 }
847
848 Function *WriteoutF = insertCounterWriteout(CountersBySP);
11
Calling 'GCOVProfiler::insertCounterWriteout'
849 Function *FlushF = insertFlush(CountersBySP);
850
851 // Create a small bit of code that registers the "__llvm_gcov_writeout" to
852 // be executed at exit and the "__llvm_gcov_flush" function to be executed
853 // when "__gcov_flush" is called.
854 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
855 Function *F = Function::Create(FTy, GlobalValue::InternalLinkage,
856 "__llvm_gcov_init", M);
857 F->setUnnamedAddr(GlobalValue::UnnamedAddr::Global);
858 F->setLinkage(GlobalValue::InternalLinkage);
859 F->addFnAttr(Attribute::NoInline);
860 if (Options.NoRedZone)
861 F->addFnAttr(Attribute::NoRedZone);
862
863 BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", F);
864 IRBuilder<> Builder(BB);
865
866 FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
867 Type *Params[] = {
868 PointerType::get(FTy, 0),
869 PointerType::get(FTy, 0)
870 };
871 FTy = FunctionType::get(Builder.getVoidTy(), Params, false);
872
873 // Initialize the environment and register the local writeout and flush
874 // functions.
875 FunctionCallee GCOVInit = M->getOrInsertFunction("llvm_gcov_init", FTy);
876 Builder.CreateCall(GCOVInit, {WriteoutF, FlushF});
877 Builder.CreateRetVoid();
878
879 appendToGlobalCtors(*M, F, 0);
880 }
881
882 return Result;
883}
884
885FunctionCallee GCOVProfiler::getStartFileFunc(const TargetLibraryInfo *TLI) {
886 Type *Args[] = {
887 Type::getInt8PtrTy(*Ctx), // const char *orig_filename
888 Type::getInt8PtrTy(*Ctx), // const char version[4]
889 Type::getInt32Ty(*Ctx), // uint32_t checksum
890 };
891 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
892 AttributeList AL;
893 if (auto AK = TLI->getExtAttrForI32Param(false))
894 AL = AL.addParamAttribute(*Ctx, 2, AK);
895 FunctionCallee Res = M->getOrInsertFunction("llvm_gcda_start_file", FTy, AL);
896 return Res;
897}
898
899FunctionCallee GCOVProfiler::getEmitFunctionFunc(const TargetLibraryInfo *TLI) {
900 Type *Args[] = {
901 Type::getInt32Ty(*Ctx), // uint32_t ident
902 Type::getInt8PtrTy(*Ctx), // const char *function_name
903 Type::getInt32Ty(*Ctx), // uint32_t func_checksum
904 Type::getInt8Ty(*Ctx), // uint8_t use_extra_checksum
905 Type::getInt32Ty(*Ctx), // uint32_t cfg_checksum
906 };
907 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
908 AttributeList AL;
909 if (auto AK = TLI->getExtAttrForI32Param(false)) {
910 AL = AL.addParamAttribute(*Ctx, 0, AK);
911 AL = AL.addParamAttribute(*Ctx, 2, AK);
912 AL = AL.addParamAttribute(*Ctx, 3, AK);
913 AL = AL.addParamAttribute(*Ctx, 4, AK);
914 }
915 return M->getOrInsertFunction("llvm_gcda_emit_function", FTy);
916}
917
918FunctionCallee GCOVProfiler::getEmitArcsFunc(const TargetLibraryInfo *TLI) {
919 Type *Args[] = {
920 Type::getInt32Ty(*Ctx), // uint32_t num_counters
921 Type::getInt64PtrTy(*Ctx), // uint64_t *counters
922 };
923 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
924 AttributeList AL;
925 if (auto AK = TLI->getExtAttrForI32Param(false))
926 AL = AL.addParamAttribute(*Ctx, 0, AK);
927 return M->getOrInsertFunction("llvm_gcda_emit_arcs", FTy, AL);
928}
929
930FunctionCallee GCOVProfiler::getSummaryInfoFunc() {
931 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
932 return M->getOrInsertFunction("llvm_gcda_summary_info", FTy);
933}
934
935FunctionCallee GCOVProfiler::getEndFileFunc() {
936 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
937 return M->getOrInsertFunction("llvm_gcda_end_file", FTy);
938}
939
940Function *GCOVProfiler::insertCounterWriteout(
941 ArrayRef<std::pair<GlobalVariable *, MDNode *> > CountersBySP) {
942 FunctionType *WriteoutFTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
943 Function *WriteoutF = M->getFunction("__llvm_gcov_writeout");
944 if (!WriteoutF)
12
Assuming 'WriteoutF' is non-null
13
Taking false branch
945 WriteoutF = Function::Create(WriteoutFTy, GlobalValue::InternalLinkage,
946 "__llvm_gcov_writeout", M);
947 WriteoutF->setUnnamedAddr(GlobalValue::UnnamedAddr::Global);
948 WriteoutF->addFnAttr(Attribute::NoInline);
949 if (Options.NoRedZone)
14
Assuming field 'NoRedZone' is false
15
Taking false branch
950 WriteoutF->addFnAttr(Attribute::NoRedZone);
951
952 BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", WriteoutF);
953 IRBuilder<> Builder(BB);
954
955 auto *TLI = &GetTLI(*WriteoutF);
956
957 FunctionCallee StartFile = getStartFileFunc(TLI);
958 FunctionCallee EmitFunction = getEmitFunctionFunc(TLI);
959 FunctionCallee EmitArcs = getEmitArcsFunc(TLI);
960 FunctionCallee SummaryInfo = getSummaryInfoFunc();
961 FunctionCallee EndFile = getEndFileFunc();
962
963 NamedMDNode *CUNodes = M->getNamedMetadata("llvm.dbg.cu");
964 if (!CUNodes) {
16
Assuming 'CUNodes' is non-null
17
Taking false branch
965 Builder.CreateRetVoid();
966 return WriteoutF;
967 }
968
969 // Collect the relevant data into a large constant data structure that we can
970 // walk to write out everything.
971 StructType *StartFileCallArgsTy = StructType::create(
972 {Builder.getInt8PtrTy(), Builder.getInt8PtrTy(), Builder.getInt32Ty()});
973 StructType *EmitFunctionCallArgsTy = StructType::create(
974 {Builder.getInt32Ty(), Builder.getInt8PtrTy(), Builder.getInt32Ty(),
975 Builder.getInt8Ty(), Builder.getInt32Ty()});
976 StructType *EmitArcsCallArgsTy = StructType::create(
977 {Builder.getInt32Ty(), Builder.getInt64Ty()->getPointerTo()});
978 StructType *FileInfoTy =
979 StructType::create({StartFileCallArgsTy, Builder.getInt32Ty(),
980 EmitFunctionCallArgsTy->getPointerTo(),
981 EmitArcsCallArgsTy->getPointerTo()});
982
983 Constant *Zero32 = Builder.getInt32(0);
984 // Build an explicit array of two zeros for use in ConstantExpr GEP building.
985 Constant *TwoZero32s[] = {Zero32, Zero32};
986
987 SmallVector<Constant *, 8> FileInfos;
988 for (int i : llvm::seq<int>(0, CUNodes->getNumOperands())) {
989 auto *CU = cast<DICompileUnit>(CUNodes->getOperand(i));
18
The object is a 'DICompileUnit'
990
991 // Skip module skeleton (and module) CUs.
992 if (CU->getDWOId())
19
Assuming the condition is false
20
Taking false branch
993 continue;
994
995 std::string FilenameGcda = mangleName(CU, GCovFileType::GCDA);
996 uint32_t CfgChecksum = FileChecksums.empty() ? 0 : FileChecksums[i];
21
'?' condition is false
997 auto *StartFileCallArgs = ConstantStruct::get(
998 StartFileCallArgsTy, {Builder.CreateGlobalStringPtr(FilenameGcda),
999 Builder.CreateGlobalStringPtr(ReversedVersion),
1000 Builder.getInt32(CfgChecksum)});
1001
1002 SmallVector<Constant *, 8> EmitFunctionCallArgsArray;
1003 SmallVector<Constant *, 8> EmitArcsCallArgsArray;
1004 for (int j : llvm::seq<int>(0, CountersBySP.size())) {
1005 auto *SP = cast_or_null<DISubprogram>(CountersBySP[j].second);
22
Assuming null pointer is passed into cast
23
'SP' initialized to a null pointer value
1006 uint32_t FuncChecksum = Funcs.empty() ? 0 : Funcs[j]->getFuncChecksum();
24
'?' condition is true
1007 EmitFunctionCallArgsArray.push_back(ConstantStruct::get(
1008 EmitFunctionCallArgsTy,
1009 {Builder.getInt32(j),
1010 Options.FunctionNamesInData
25
Assuming field 'FunctionNamesInData' is true
26
'?' condition is true
1011 ? Builder.CreateGlobalStringPtr(getFunctionName(SP))
27
Passing null pointer value via 1st parameter 'SP'
28
Calling 'getFunctionName'
1012 : Constant::getNullValue(Builder.getInt8PtrTy()),
1013 Builder.getInt32(FuncChecksum),
1014 Builder.getInt8(Options.UseCfgChecksum),
1015 Builder.getInt32(CfgChecksum)}));
1016
1017 GlobalVariable *GV = CountersBySP[j].first;
1018 unsigned Arcs = cast<ArrayType>(GV->getValueType())->getNumElements();
1019 EmitArcsCallArgsArray.push_back(ConstantStruct::get(
1020 EmitArcsCallArgsTy,
1021 {Builder.getInt32(Arcs), ConstantExpr::getInBoundsGetElementPtr(
1022 GV->getValueType(), GV, TwoZero32s)}));
1023 }
1024 // Create global arrays for the two emit calls.
1025 int CountersSize = CountersBySP.size();
1026 assert(CountersSize == (int)EmitFunctionCallArgsArray.size() &&((CountersSize == (int)EmitFunctionCallArgsArray.size() &&
"Mismatched array size!") ? static_cast<void> (0) : __assert_fail
("CountersSize == (int)EmitFunctionCallArgsArray.size() && \"Mismatched array size!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp"
, 1027, __PRETTY_FUNCTION__))
1027 "Mismatched array size!")((CountersSize == (int)EmitFunctionCallArgsArray.size() &&
"Mismatched array size!") ? static_cast<void> (0) : __assert_fail
("CountersSize == (int)EmitFunctionCallArgsArray.size() && \"Mismatched array size!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp"
, 1027, __PRETTY_FUNCTION__))
;
1028 assert(CountersSize == (int)EmitArcsCallArgsArray.size() &&((CountersSize == (int)EmitArcsCallArgsArray.size() &&
"Mismatched array size!") ? static_cast<void> (0) : __assert_fail
("CountersSize == (int)EmitArcsCallArgsArray.size() && \"Mismatched array size!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp"
, 1029, __PRETTY_FUNCTION__))
1029 "Mismatched array size!")((CountersSize == (int)EmitArcsCallArgsArray.size() &&
"Mismatched array size!") ? static_cast<void> (0) : __assert_fail
("CountersSize == (int)EmitArcsCallArgsArray.size() && \"Mismatched array size!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp"
, 1029, __PRETTY_FUNCTION__))
;
1030 auto *EmitFunctionCallArgsArrayTy =
1031 ArrayType::get(EmitFunctionCallArgsTy, CountersSize);
1032 auto *EmitFunctionCallArgsArrayGV = new GlobalVariable(
1033 *M, EmitFunctionCallArgsArrayTy, /*isConstant*/ true,
1034 GlobalValue::InternalLinkage,
1035 ConstantArray::get(EmitFunctionCallArgsArrayTy,
1036 EmitFunctionCallArgsArray),
1037 Twine("__llvm_internal_gcov_emit_function_args.") + Twine(i));
1038 auto *EmitArcsCallArgsArrayTy =
1039 ArrayType::get(EmitArcsCallArgsTy, CountersSize);
1040 EmitFunctionCallArgsArrayGV->setUnnamedAddr(
1041 GlobalValue::UnnamedAddr::Global);
1042 auto *EmitArcsCallArgsArrayGV = new GlobalVariable(
1043 *M, EmitArcsCallArgsArrayTy, /*isConstant*/ true,
1044 GlobalValue::InternalLinkage,
1045 ConstantArray::get(EmitArcsCallArgsArrayTy, EmitArcsCallArgsArray),
1046 Twine("__llvm_internal_gcov_emit_arcs_args.") + Twine(i));
1047 EmitArcsCallArgsArrayGV->setUnnamedAddr(GlobalValue::UnnamedAddr::Global);
1048
1049 FileInfos.push_back(ConstantStruct::get(
1050 FileInfoTy,
1051 {StartFileCallArgs, Builder.getInt32(CountersSize),
1052 ConstantExpr::getInBoundsGetElementPtr(EmitFunctionCallArgsArrayTy,
1053 EmitFunctionCallArgsArrayGV,
1054 TwoZero32s),
1055 ConstantExpr::getInBoundsGetElementPtr(
1056 EmitArcsCallArgsArrayTy, EmitArcsCallArgsArrayGV, TwoZero32s)}));
1057 }
1058
1059 // If we didn't find anything to actually emit, bail on out.
1060 if (FileInfos.empty()) {
1061 Builder.CreateRetVoid();
1062 return WriteoutF;
1063 }
1064
1065 // To simplify code, we cap the number of file infos we write out to fit
1066 // easily in a 32-bit signed integer. This gives consistent behavior between
1067 // 32-bit and 64-bit systems without requiring (potentially very slow) 64-bit
1068 // operations on 32-bit systems. It also seems unreasonable to try to handle
1069 // more than 2 billion files.
1070 if ((int64_t)FileInfos.size() > (int64_t)INT_MAX2147483647)
1071 FileInfos.resize(INT_MAX2147483647);
1072
1073 // Create a global for the entire data structure so we can walk it more
1074 // easily.
1075 auto *FileInfoArrayTy = ArrayType::get(FileInfoTy, FileInfos.size());
1076 auto *FileInfoArrayGV = new GlobalVariable(
1077 *M, FileInfoArrayTy, /*isConstant*/ true, GlobalValue::InternalLinkage,
1078 ConstantArray::get(FileInfoArrayTy, FileInfos),
1079 "__llvm_internal_gcov_emit_file_info");
1080 FileInfoArrayGV->setUnnamedAddr(GlobalValue::UnnamedAddr::Global);
1081
1082 // Create the CFG for walking this data structure.
1083 auto *FileLoopHeader =
1084 BasicBlock::Create(*Ctx, "file.loop.header", WriteoutF);
1085 auto *CounterLoopHeader =
1086 BasicBlock::Create(*Ctx, "counter.loop.header", WriteoutF);
1087 auto *FileLoopLatch = BasicBlock::Create(*Ctx, "file.loop.latch", WriteoutF);
1088 auto *ExitBB = BasicBlock::Create(*Ctx, "exit", WriteoutF);
1089
1090 // We always have at least one file, so just branch to the header.
1091 Builder.CreateBr(FileLoopHeader);
1092
1093 // The index into the files structure is our loop induction variable.
1094 Builder.SetInsertPoint(FileLoopHeader);
1095 PHINode *IV =
1096 Builder.CreatePHI(Builder.getInt32Ty(), /*NumReservedValues*/ 2);
1097 IV->addIncoming(Builder.getInt32(0), BB);
1098 auto *FileInfoPtr = Builder.CreateInBoundsGEP(
1099 FileInfoArrayTy, FileInfoArrayGV, {Builder.getInt32(0), IV});
1100 auto *StartFileCallArgsPtr =
1101 Builder.CreateStructGEP(FileInfoTy, FileInfoPtr, 0);
1102 auto *StartFileCall = Builder.CreateCall(
1103 StartFile,
1104 {Builder.CreateLoad(StartFileCallArgsTy->getElementType(0),
1105 Builder.CreateStructGEP(StartFileCallArgsTy,
1106 StartFileCallArgsPtr, 0)),
1107 Builder.CreateLoad(StartFileCallArgsTy->getElementType(1),
1108 Builder.CreateStructGEP(StartFileCallArgsTy,
1109 StartFileCallArgsPtr, 1)),
1110 Builder.CreateLoad(StartFileCallArgsTy->getElementType(2),
1111 Builder.CreateStructGEP(StartFileCallArgsTy,
1112 StartFileCallArgsPtr, 2))});
1113 if (auto AK = TLI->getExtAttrForI32Param(false))
1114 StartFileCall->addParamAttr(2, AK);
1115 auto *NumCounters =
1116 Builder.CreateLoad(FileInfoTy->getElementType(1),
1117 Builder.CreateStructGEP(FileInfoTy, FileInfoPtr, 1));
1118 auto *EmitFunctionCallArgsArray =
1119 Builder.CreateLoad(FileInfoTy->getElementType(2),
1120 Builder.CreateStructGEP(FileInfoTy, FileInfoPtr, 2));
1121 auto *EmitArcsCallArgsArray =
1122 Builder.CreateLoad(FileInfoTy->getElementType(3),
1123 Builder.CreateStructGEP(FileInfoTy, FileInfoPtr, 3));
1124 auto *EnterCounterLoopCond =
1125 Builder.CreateICmpSLT(Builder.getInt32(0), NumCounters);
1126 Builder.CreateCondBr(EnterCounterLoopCond, CounterLoopHeader, FileLoopLatch);
1127
1128 Builder.SetInsertPoint(CounterLoopHeader);
1129 auto *JV = Builder.CreatePHI(Builder.getInt32Ty(), /*NumReservedValues*/ 2);
1130 JV->addIncoming(Builder.getInt32(0), FileLoopHeader);
1131 auto *EmitFunctionCallArgsPtr = Builder.CreateInBoundsGEP(
1132 EmitFunctionCallArgsTy, EmitFunctionCallArgsArray, JV);
1133 auto *EmitFunctionCall = Builder.CreateCall(
1134 EmitFunction,
1135 {Builder.CreateLoad(EmitFunctionCallArgsTy->getElementType(0),
1136 Builder.CreateStructGEP(EmitFunctionCallArgsTy,
1137 EmitFunctionCallArgsPtr, 0)),
1138 Builder.CreateLoad(EmitFunctionCallArgsTy->getElementType(1),
1139 Builder.CreateStructGEP(EmitFunctionCallArgsTy,
1140 EmitFunctionCallArgsPtr, 1)),
1141 Builder.CreateLoad(EmitFunctionCallArgsTy->getElementType(2),
1142 Builder.CreateStructGEP(EmitFunctionCallArgsTy,
1143 EmitFunctionCallArgsPtr, 2)),
1144 Builder.CreateLoad(EmitFunctionCallArgsTy->getElementType(3),
1145 Builder.CreateStructGEP(EmitFunctionCallArgsTy,
1146 EmitFunctionCallArgsPtr, 3)),
1147 Builder.CreateLoad(EmitFunctionCallArgsTy->getElementType(4),
1148 Builder.CreateStructGEP(EmitFunctionCallArgsTy,
1149 EmitFunctionCallArgsPtr,
1150 4))});
1151 if (auto AK = TLI->getExtAttrForI32Param(false)) {
1152 EmitFunctionCall->addParamAttr(0, AK);
1153 EmitFunctionCall->addParamAttr(2, AK);
1154 EmitFunctionCall->addParamAttr(3, AK);
1155 EmitFunctionCall->addParamAttr(4, AK);
1156 }
1157 auto *EmitArcsCallArgsPtr =
1158 Builder.CreateInBoundsGEP(EmitArcsCallArgsTy, EmitArcsCallArgsArray, JV);
1159 auto *EmitArcsCall = Builder.CreateCall(
1160 EmitArcs,
1161 {Builder.CreateLoad(
1162 EmitArcsCallArgsTy->getElementType(0),
1163 Builder.CreateStructGEP(EmitArcsCallArgsTy, EmitArcsCallArgsPtr, 0)),
1164 Builder.CreateLoad(EmitArcsCallArgsTy->getElementType(1),
1165 Builder.CreateStructGEP(EmitArcsCallArgsTy,
1166 EmitArcsCallArgsPtr, 1))});
1167 if (auto AK = TLI->getExtAttrForI32Param(false))
1168 EmitArcsCall->addParamAttr(0, AK);
1169 auto *NextJV = Builder.CreateAdd(JV, Builder.getInt32(1));
1170 auto *CounterLoopCond = Builder.CreateICmpSLT(NextJV, NumCounters);
1171 Builder.CreateCondBr(CounterLoopCond, CounterLoopHeader, FileLoopLatch);
1172 JV->addIncoming(NextJV, CounterLoopHeader);
1173
1174 Builder.SetInsertPoint(FileLoopLatch);
1175 Builder.CreateCall(SummaryInfo, {});
1176 Builder.CreateCall(EndFile, {});
1177 auto *NextIV = Builder.CreateAdd(IV, Builder.getInt32(1));
1178 auto *FileLoopCond =
1179 Builder.CreateICmpSLT(NextIV, Builder.getInt32(FileInfos.size()));
1180 Builder.CreateCondBr(FileLoopCond, FileLoopHeader, ExitBB);
1181 IV->addIncoming(NextIV, FileLoopLatch);
1182
1183 Builder.SetInsertPoint(ExitBB);
1184 Builder.CreateRetVoid();
1185
1186 return WriteoutF;
1187}
1188
1189Function *GCOVProfiler::
1190insertFlush(ArrayRef<std::pair<GlobalVariable*, MDNode*> > CountersBySP) {
1191 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
1192 Function *FlushF = M->getFunction("__llvm_gcov_flush");
1193 if (!FlushF)
1194 FlushF = Function::Create(FTy, GlobalValue::InternalLinkage,
1195 "__llvm_gcov_flush", M);
1196 else
1197 FlushF->setLinkage(GlobalValue::InternalLinkage);
1198 FlushF->setUnnamedAddr(GlobalValue::UnnamedAddr::Global);
1199 FlushF->addFnAttr(Attribute::NoInline);
1200 if (Options.NoRedZone)
1201 FlushF->addFnAttr(Attribute::NoRedZone);
1202
1203 BasicBlock *Entry = BasicBlock::Create(*Ctx, "entry", FlushF);
1204
1205 // Write out the current counters.
1206 Function *WriteoutF = M->getFunction("__llvm_gcov_writeout");
1207 assert(WriteoutF && "Need to create the writeout function first!")((WriteoutF && "Need to create the writeout function first!"
) ? static_cast<void> (0) : __assert_fail ("WriteoutF && \"Need to create the writeout function first!\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp"
, 1207, __PRETTY_FUNCTION__))
;
1208
1209 IRBuilder<> Builder(Entry);
1210 Builder.CreateCall(WriteoutF, {});
1211
1212 // Zero out the counters.
1213 for (const auto &I : CountersBySP) {
1214 GlobalVariable *GV = I.first;
1215 Constant *Null = Constant::getNullValue(GV->getValueType());
1216 Builder.CreateStore(Null, GV);
1217 }
1218
1219 Type *RetTy = FlushF->getReturnType();
1220 if (RetTy == Type::getVoidTy(*Ctx))
1221 Builder.CreateRetVoid();
1222 else if (RetTy->isIntegerTy())
1223 // Used if __llvm_gcov_flush was implicitly declared.
1224 Builder.CreateRet(ConstantInt::get(RetTy, 0));
1225 else
1226 report_fatal_error("invalid return type for __llvm_gcov_flush");
1227
1228 return FlushF;
1229}