LLVM 17.0.0git
SanitizerCoverage.cpp
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1//===-- SanitizerCoverage.cpp - coverage instrumentation for sanitizers ---===//
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// Coverage instrumentation done on LLVM IR level, works with Sanitizers.
10//
11//===----------------------------------------------------------------------===//
12
14#include "llvm/ADT/ArrayRef.h"
18#include "llvm/IR/Constant.h"
19#include "llvm/IR/DataLayout.h"
20#include "llvm/IR/Dominators.h"
22#include "llvm/IR/Function.h"
24#include "llvm/IR/IRBuilder.h"
26#include "llvm/IR/Intrinsics.h"
27#include "llvm/IR/LLVMContext.h"
28#include "llvm/IR/Module.h"
29#include "llvm/IR/Type.h"
36
37using namespace llvm;
38
39#define DEBUG_TYPE "sancov"
40
41const char SanCovTracePCIndirName[] = "__sanitizer_cov_trace_pc_indir";
42const char SanCovTracePCName[] = "__sanitizer_cov_trace_pc";
43const char SanCovTraceCmp1[] = "__sanitizer_cov_trace_cmp1";
44const char SanCovTraceCmp2[] = "__sanitizer_cov_trace_cmp2";
45const char SanCovTraceCmp4[] = "__sanitizer_cov_trace_cmp4";
46const char SanCovTraceCmp8[] = "__sanitizer_cov_trace_cmp8";
47const char SanCovTraceConstCmp1[] = "__sanitizer_cov_trace_const_cmp1";
48const char SanCovTraceConstCmp2[] = "__sanitizer_cov_trace_const_cmp2";
49const char SanCovTraceConstCmp4[] = "__sanitizer_cov_trace_const_cmp4";
50const char SanCovTraceConstCmp8[] = "__sanitizer_cov_trace_const_cmp8";
51const char SanCovLoad1[] = "__sanitizer_cov_load1";
52const char SanCovLoad2[] = "__sanitizer_cov_load2";
53const char SanCovLoad4[] = "__sanitizer_cov_load4";
54const char SanCovLoad8[] = "__sanitizer_cov_load8";
55const char SanCovLoad16[] = "__sanitizer_cov_load16";
56const char SanCovStore1[] = "__sanitizer_cov_store1";
57const char SanCovStore2[] = "__sanitizer_cov_store2";
58const char SanCovStore4[] = "__sanitizer_cov_store4";
59const char SanCovStore8[] = "__sanitizer_cov_store8";
60const char SanCovStore16[] = "__sanitizer_cov_store16";
61const char SanCovTraceDiv4[] = "__sanitizer_cov_trace_div4";
62const char SanCovTraceDiv8[] = "__sanitizer_cov_trace_div8";
63const char SanCovTraceGep[] = "__sanitizer_cov_trace_gep";
64const char SanCovTraceSwitchName[] = "__sanitizer_cov_trace_switch";
66 "sancov.module_ctor_trace_pc_guard";
68 "sancov.module_ctor_8bit_counters";
69const char SanCovModuleCtorBoolFlagName[] = "sancov.module_ctor_bool_flag";
71
72const char SanCovTracePCGuardName[] = "__sanitizer_cov_trace_pc_guard";
73const char SanCovTracePCGuardInitName[] = "__sanitizer_cov_trace_pc_guard_init";
74const char SanCov8bitCountersInitName[] = "__sanitizer_cov_8bit_counters_init";
75const char SanCovBoolFlagInitName[] = "__sanitizer_cov_bool_flag_init";
76const char SanCovPCsInitName[] = "__sanitizer_cov_pcs_init";
77const char SanCovCFsInitName[] = "__sanitizer_cov_cfs_init";
78
79const char SanCovGuardsSectionName[] = "sancov_guards";
80const char SanCovCountersSectionName[] = "sancov_cntrs";
81const char SanCovBoolFlagSectionName[] = "sancov_bools";
82const char SanCovPCsSectionName[] = "sancov_pcs";
83const char SanCovCFsSectionName[] = "sancov_cfs";
84
85const char SanCovLowestStackName[] = "__sancov_lowest_stack";
86
88 "sanitizer-coverage-level",
89 cl::desc("Sanitizer Coverage. 0: none, 1: entry block, 2: all blocks, "
90 "3: all blocks and critical edges"),
92
93static cl::opt<bool> ClTracePC("sanitizer-coverage-trace-pc",
94 cl::desc("Experimental pc tracing"), cl::Hidden,
95 cl::init(false));
96
97static cl::opt<bool> ClTracePCGuard("sanitizer-coverage-trace-pc-guard",
98 cl::desc("pc tracing with a guard"),
99 cl::Hidden, cl::init(false));
100
101// If true, we create a global variable that contains PCs of all instrumented
102// BBs, put this global into a named section, and pass this section's bounds
103// to __sanitizer_cov_pcs_init.
104// This way the coverage instrumentation does not need to acquire the PCs
105// at run-time. Works with trace-pc-guard, inline-8bit-counters, and
106// inline-bool-flag.
107static cl::opt<bool> ClCreatePCTable("sanitizer-coverage-pc-table",
108 cl::desc("create a static PC table"),
109 cl::Hidden, cl::init(false));
110
111static cl::opt<bool>
112 ClInline8bitCounters("sanitizer-coverage-inline-8bit-counters",
113 cl::desc("increments 8-bit counter for every edge"),
114 cl::Hidden, cl::init(false));
115
116static cl::opt<bool>
117 ClInlineBoolFlag("sanitizer-coverage-inline-bool-flag",
118 cl::desc("sets a boolean flag for every edge"), cl::Hidden,
119 cl::init(false));
120
121static cl::opt<bool>
122 ClCMPTracing("sanitizer-coverage-trace-compares",
123 cl::desc("Tracing of CMP and similar instructions"),
124 cl::Hidden, cl::init(false));
125
126static cl::opt<bool> ClDIVTracing("sanitizer-coverage-trace-divs",
127 cl::desc("Tracing of DIV instructions"),
128 cl::Hidden, cl::init(false));
129
130static cl::opt<bool> ClLoadTracing("sanitizer-coverage-trace-loads",
131 cl::desc("Tracing of load instructions"),
132 cl::Hidden, cl::init(false));
133
134static cl::opt<bool> ClStoreTracing("sanitizer-coverage-trace-stores",
135 cl::desc("Tracing of store instructions"),
136 cl::Hidden, cl::init(false));
137
138static cl::opt<bool> ClGEPTracing("sanitizer-coverage-trace-geps",
139 cl::desc("Tracing of GEP instructions"),
140 cl::Hidden, cl::init(false));
141
142static cl::opt<bool>
143 ClPruneBlocks("sanitizer-coverage-prune-blocks",
144 cl::desc("Reduce the number of instrumented blocks"),
145 cl::Hidden, cl::init(true));
146
147static cl::opt<bool> ClStackDepth("sanitizer-coverage-stack-depth",
148 cl::desc("max stack depth tracing"),
149 cl::Hidden, cl::init(false));
150
151static cl::opt<bool>
152 ClCollectCF("sanitizer-coverage-control-flow",
153 cl::desc("collect control flow for each function"), cl::Hidden,
154 cl::init(false));
155
156namespace {
157
158SanitizerCoverageOptions getOptions(int LegacyCoverageLevel) {
160 switch (LegacyCoverageLevel) {
161 case 0:
163 break;
164 case 1:
166 break;
167 case 2:
169 break;
170 case 3:
172 break;
173 case 4:
175 Res.IndirectCalls = true;
176 break;
177 }
178 return Res;
179}
180
182 // Sets CoverageType and IndirectCalls.
183 SanitizerCoverageOptions CLOpts = getOptions(ClCoverageLevel);
184 Options.CoverageType = std::max(Options.CoverageType, CLOpts.CoverageType);
185 Options.IndirectCalls |= CLOpts.IndirectCalls;
186 Options.TraceCmp |= ClCMPTracing;
187 Options.TraceDiv |= ClDIVTracing;
188 Options.TraceGep |= ClGEPTracing;
189 Options.TracePC |= ClTracePC;
190 Options.TracePCGuard |= ClTracePCGuard;
191 Options.Inline8bitCounters |= ClInline8bitCounters;
192 Options.InlineBoolFlag |= ClInlineBoolFlag;
193 Options.PCTable |= ClCreatePCTable;
194 Options.NoPrune |= !ClPruneBlocks;
195 Options.StackDepth |= ClStackDepth;
196 Options.TraceLoads |= ClLoadTracing;
197 Options.TraceStores |= ClStoreTracing;
198 if (!Options.TracePCGuard && !Options.TracePC &&
199 !Options.Inline8bitCounters && !Options.StackDepth &&
200 !Options.InlineBoolFlag && !Options.TraceLoads && !Options.TraceStores)
201 Options.TracePCGuard = true; // TracePCGuard is default.
202 Options.CollectControlFlow |= ClCollectCF;
203 return Options;
204}
205
206using DomTreeCallback = function_ref<const DominatorTree *(Function &F)>;
207using PostDomTreeCallback =
209
210class ModuleSanitizerCoverage {
211public:
212 ModuleSanitizerCoverage(
214 const SpecialCaseList *Allowlist = nullptr,
215 const SpecialCaseList *Blocklist = nullptr)
216 : Options(OverrideFromCL(Options)), Allowlist(Allowlist),
217 Blocklist(Blocklist) {}
218 bool instrumentModule(Module &M, DomTreeCallback DTCallback,
219 PostDomTreeCallback PDTCallback);
220
221private:
222 void createFunctionControlFlow(Function &F);
223 void instrumentFunction(Function &F, DomTreeCallback DTCallback,
224 PostDomTreeCallback PDTCallback);
225 void InjectCoverageForIndirectCalls(Function &F,
226 ArrayRef<Instruction *> IndirCalls);
227 void InjectTraceForCmp(Function &F, ArrayRef<Instruction *> CmpTraceTargets);
228 void InjectTraceForDiv(Function &F,
229 ArrayRef<BinaryOperator *> DivTraceTargets);
230 void InjectTraceForGep(Function &F,
231 ArrayRef<GetElementPtrInst *> GepTraceTargets);
232 void InjectTraceForLoadsAndStores(Function &F, ArrayRef<LoadInst *> Loads,
233 ArrayRef<StoreInst *> Stores);
234 void InjectTraceForSwitch(Function &F,
235 ArrayRef<Instruction *> SwitchTraceTargets);
236 bool InjectCoverage(Function &F, ArrayRef<BasicBlock *> AllBlocks,
237 bool IsLeafFunc = true);
238 GlobalVariable *CreateFunctionLocalArrayInSection(size_t NumElements,
239 Function &F, Type *Ty,
240 const char *Section);
241 GlobalVariable *CreatePCArray(Function &F, ArrayRef<BasicBlock *> AllBlocks);
242 void CreateFunctionLocalArrays(Function &F, ArrayRef<BasicBlock *> AllBlocks);
243 void InjectCoverageAtBlock(Function &F, BasicBlock &BB, size_t Idx,
244 bool IsLeafFunc = true);
245 Function *CreateInitCallsForSections(Module &M, const char *CtorName,
246 const char *InitFunctionName, Type *Ty,
247 const char *Section);
248 std::pair<Value *, Value *> CreateSecStartEnd(Module &M, const char *Section,
249 Type *Ty);
250
251 std::string getSectionName(const std::string &Section) const;
252 std::string getSectionStart(const std::string &Section) const;
253 std::string getSectionEnd(const std::string &Section) const;
254 FunctionCallee SanCovTracePCIndir;
255 FunctionCallee SanCovTracePC, SanCovTracePCGuard;
256 std::array<FunctionCallee, 4> SanCovTraceCmpFunction;
257 std::array<FunctionCallee, 4> SanCovTraceConstCmpFunction;
258 std::array<FunctionCallee, 5> SanCovLoadFunction;
259 std::array<FunctionCallee, 5> SanCovStoreFunction;
260 std::array<FunctionCallee, 2> SanCovTraceDivFunction;
261 FunctionCallee SanCovTraceGepFunction;
262 FunctionCallee SanCovTraceSwitchFunction;
263 GlobalVariable *SanCovLowestStack;
264 Type *Int128PtrTy, *IntptrTy, *IntptrPtrTy, *Int64Ty, *Int64PtrTy, *Int32Ty,
265 *Int32PtrTy, *Int16PtrTy, *Int16Ty, *Int8Ty, *Int8PtrTy, *Int1Ty,
266 *Int1PtrTy;
267 Module *CurModule;
268 std::string CurModuleUniqueId;
269 Triple TargetTriple;
270 LLVMContext *C;
271 const DataLayout *DL;
272
273 GlobalVariable *FunctionGuardArray; // for trace-pc-guard.
274 GlobalVariable *Function8bitCounterArray; // for inline-8bit-counters.
275 GlobalVariable *FunctionBoolArray; // for inline-bool-flag.
276 GlobalVariable *FunctionPCsArray; // for pc-table.
277 GlobalVariable *FunctionCFsArray; // for control flow table
278 SmallVector<GlobalValue *, 20> GlobalsToAppendToUsed;
279 SmallVector<GlobalValue *, 20> GlobalsToAppendToCompilerUsed;
280
282
283 const SpecialCaseList *Allowlist;
284 const SpecialCaseList *Blocklist;
285};
286} // namespace
287
290 ModuleSanitizerCoverage ModuleSancov(Options, Allowlist.get(),
291 Blocklist.get());
292 auto &FAM = MAM.getResult<FunctionAnalysisManagerModuleProxy>(M).getManager();
293 auto DTCallback = [&FAM](Function &F) -> const DominatorTree * {
295 };
296 auto PDTCallback = [&FAM](Function &F) -> const PostDominatorTree * {
298 };
299 if (!ModuleSancov.instrumentModule(M, DTCallback, PDTCallback))
300 return PreservedAnalyses::all();
301
303 // GlobalsAA is considered stateless and does not get invalidated unless
304 // explicitly invalidated; PreservedAnalyses::none() is not enough. Sanitizers
305 // make changes that require GlobalsAA to be invalidated.
306 PA.abandon<GlobalsAA>();
307 return PA;
308}
309
310std::pair<Value *, Value *>
311ModuleSanitizerCoverage::CreateSecStartEnd(Module &M, const char *Section,
312 Type *Ty) {
313 // Use ExternalWeak so that if all sections are discarded due to section
314 // garbage collection, the linker will not report undefined symbol errors.
315 // Windows defines the start/stop symbols in compiler-rt so no need for
316 // ExternalWeak.
317 GlobalValue::LinkageTypes Linkage = TargetTriple.isOSBinFormatCOFF()
320 GlobalVariable *SecStart =
321 new GlobalVariable(M, Ty, false, Linkage, nullptr,
322 getSectionStart(Section));
324 GlobalVariable *SecEnd =
325 new GlobalVariable(M, Ty, false, Linkage, nullptr,
326 getSectionEnd(Section));
328 IRBuilder<> IRB(M.getContext());
329 if (!TargetTriple.isOSBinFormatCOFF())
330 return std::make_pair(SecStart, SecEnd);
331
332 // Account for the fact that on windows-msvc __start_* symbols actually
333 // point to a uint64_t before the start of the array.
334 auto SecStartI8Ptr = IRB.CreatePointerCast(SecStart, Int8PtrTy);
335 auto GEP = IRB.CreateGEP(Int8Ty, SecStartI8Ptr,
336 ConstantInt::get(IntptrTy, sizeof(uint64_t)));
337 return std::make_pair(IRB.CreatePointerCast(GEP, PointerType::getUnqual(Ty)),
338 SecEnd);
339}
340
341Function *ModuleSanitizerCoverage::CreateInitCallsForSections(
342 Module &M, const char *CtorName, const char *InitFunctionName, Type *Ty,
343 const char *Section) {
344 auto SecStartEnd = CreateSecStartEnd(M, Section, Ty);
345 auto SecStart = SecStartEnd.first;
346 auto SecEnd = SecStartEnd.second;
347 Function *CtorFunc;
348 Type *PtrTy = PointerType::getUnqual(Ty);
349 std::tie(CtorFunc, std::ignore) = createSanitizerCtorAndInitFunctions(
350 M, CtorName, InitFunctionName, {PtrTy, PtrTy}, {SecStart, SecEnd});
351 assert(CtorFunc->getName() == CtorName);
352
353 if (TargetTriple.supportsCOMDAT()) {
354 // Use comdat to dedup CtorFunc.
355 CtorFunc->setComdat(M.getOrInsertComdat(CtorName));
356 appendToGlobalCtors(M, CtorFunc, SanCtorAndDtorPriority, CtorFunc);
357 } else {
359 }
360
361 if (TargetTriple.isOSBinFormatCOFF()) {
362 // In COFF files, if the contructors are set as COMDAT (they are because
363 // COFF supports COMDAT) and the linker flag /OPT:REF (strip unreferenced
364 // functions and data) is used, the constructors get stripped. To prevent
365 // this, give the constructors weak ODR linkage and ensure the linker knows
366 // to include the sancov constructor. This way the linker can deduplicate
367 // the constructors but always leave one copy.
369 }
370 return CtorFunc;
371}
372
373bool ModuleSanitizerCoverage::instrumentModule(
374 Module &M, DomTreeCallback DTCallback, PostDomTreeCallback PDTCallback) {
376 return false;
377 if (Allowlist &&
378 !Allowlist->inSection("coverage", "src", M.getSourceFileName()))
379 return false;
380 if (Blocklist &&
381 Blocklist->inSection("coverage", "src", M.getSourceFileName()))
382 return false;
383 C = &(M.getContext());
384 DL = &M.getDataLayout();
385 CurModule = &M;
386 CurModuleUniqueId = getUniqueModuleId(CurModule);
387 TargetTriple = Triple(M.getTargetTriple());
388 FunctionGuardArray = nullptr;
389 Function8bitCounterArray = nullptr;
390 FunctionBoolArray = nullptr;
391 FunctionPCsArray = nullptr;
392 FunctionCFsArray = nullptr;
393 IntptrTy = Type::getIntNTy(*C, DL->getPointerSizeInBits());
394 IntptrPtrTy = PointerType::getUnqual(IntptrTy);
395 Type *VoidTy = Type::getVoidTy(*C);
396 IRBuilder<> IRB(*C);
397 Int128PtrTy = PointerType::getUnqual(IRB.getInt128Ty());
398 Int64PtrTy = PointerType::getUnqual(IRB.getInt64Ty());
399 Int16PtrTy = PointerType::getUnqual(IRB.getInt16Ty());
400 Int32PtrTy = PointerType::getUnqual(IRB.getInt32Ty());
401 Int8PtrTy = PointerType::getUnqual(IRB.getInt8Ty());
402 Int1PtrTy = PointerType::getUnqual(IRB.getInt1Ty());
403 Int64Ty = IRB.getInt64Ty();
404 Int32Ty = IRB.getInt32Ty();
405 Int16Ty = IRB.getInt16Ty();
406 Int8Ty = IRB.getInt8Ty();
407 Int1Ty = IRB.getInt1Ty();
408
409 SanCovTracePCIndir =
410 M.getOrInsertFunction(SanCovTracePCIndirName, VoidTy, IntptrTy);
411 // Make sure smaller parameters are zero-extended to i64 if required by the
412 // target ABI.
413 AttributeList SanCovTraceCmpZeroExtAL;
414 SanCovTraceCmpZeroExtAL =
415 SanCovTraceCmpZeroExtAL.addParamAttribute(*C, 0, Attribute::ZExt);
416 SanCovTraceCmpZeroExtAL =
417 SanCovTraceCmpZeroExtAL.addParamAttribute(*C, 1, Attribute::ZExt);
418
419 SanCovTraceCmpFunction[0] =
420 M.getOrInsertFunction(SanCovTraceCmp1, SanCovTraceCmpZeroExtAL, VoidTy,
421 IRB.getInt8Ty(), IRB.getInt8Ty());
422 SanCovTraceCmpFunction[1] =
423 M.getOrInsertFunction(SanCovTraceCmp2, SanCovTraceCmpZeroExtAL, VoidTy,
424 IRB.getInt16Ty(), IRB.getInt16Ty());
425 SanCovTraceCmpFunction[2] =
426 M.getOrInsertFunction(SanCovTraceCmp4, SanCovTraceCmpZeroExtAL, VoidTy,
427 IRB.getInt32Ty(), IRB.getInt32Ty());
428 SanCovTraceCmpFunction[3] =
429 M.getOrInsertFunction(SanCovTraceCmp8, VoidTy, Int64Ty, Int64Ty);
430
431 SanCovTraceConstCmpFunction[0] = M.getOrInsertFunction(
432 SanCovTraceConstCmp1, SanCovTraceCmpZeroExtAL, VoidTy, Int8Ty, Int8Ty);
433 SanCovTraceConstCmpFunction[1] = M.getOrInsertFunction(
434 SanCovTraceConstCmp2, SanCovTraceCmpZeroExtAL, VoidTy, Int16Ty, Int16Ty);
435 SanCovTraceConstCmpFunction[2] = M.getOrInsertFunction(
436 SanCovTraceConstCmp4, SanCovTraceCmpZeroExtAL, VoidTy, Int32Ty, Int32Ty);
437 SanCovTraceConstCmpFunction[3] =
438 M.getOrInsertFunction(SanCovTraceConstCmp8, VoidTy, Int64Ty, Int64Ty);
439
440 // Loads.
441 SanCovLoadFunction[0] = M.getOrInsertFunction(SanCovLoad1, VoidTy, Int8PtrTy);
442 SanCovLoadFunction[1] =
443 M.getOrInsertFunction(SanCovLoad2, VoidTy, Int16PtrTy);
444 SanCovLoadFunction[2] =
445 M.getOrInsertFunction(SanCovLoad4, VoidTy, Int32PtrTy);
446 SanCovLoadFunction[3] =
447 M.getOrInsertFunction(SanCovLoad8, VoidTy, Int64PtrTy);
448 SanCovLoadFunction[4] =
449 M.getOrInsertFunction(SanCovLoad16, VoidTy, Int128PtrTy);
450 // Stores.
451 SanCovStoreFunction[0] =
452 M.getOrInsertFunction(SanCovStore1, VoidTy, Int8PtrTy);
453 SanCovStoreFunction[1] =
454 M.getOrInsertFunction(SanCovStore2, VoidTy, Int16PtrTy);
455 SanCovStoreFunction[2] =
456 M.getOrInsertFunction(SanCovStore4, VoidTy, Int32PtrTy);
457 SanCovStoreFunction[3] =
458 M.getOrInsertFunction(SanCovStore8, VoidTy, Int64PtrTy);
459 SanCovStoreFunction[4] =
460 M.getOrInsertFunction(SanCovStore16, VoidTy, Int128PtrTy);
461
462 {
464 AL = AL.addParamAttribute(*C, 0, Attribute::ZExt);
465 SanCovTraceDivFunction[0] =
466 M.getOrInsertFunction(SanCovTraceDiv4, AL, VoidTy, IRB.getInt32Ty());
467 }
468 SanCovTraceDivFunction[1] =
469 M.getOrInsertFunction(SanCovTraceDiv8, VoidTy, Int64Ty);
470 SanCovTraceGepFunction =
471 M.getOrInsertFunction(SanCovTraceGep, VoidTy, IntptrTy);
472 SanCovTraceSwitchFunction =
473 M.getOrInsertFunction(SanCovTraceSwitchName, VoidTy, Int64Ty, Int64PtrTy);
474
475 Constant *SanCovLowestStackConstant =
476 M.getOrInsertGlobal(SanCovLowestStackName, IntptrTy);
477 SanCovLowestStack = dyn_cast<GlobalVariable>(SanCovLowestStackConstant);
478 if (!SanCovLowestStack || SanCovLowestStack->getValueType() != IntptrTy) {
479 C->emitError(StringRef("'") + SanCovLowestStackName +
480 "' should not be declared by the user");
481 return true;
482 }
483 SanCovLowestStack->setThreadLocalMode(
485 if (Options.StackDepth && !SanCovLowestStack->isDeclaration())
486 SanCovLowestStack->setInitializer(Constant::getAllOnesValue(IntptrTy));
487
488 SanCovTracePC = M.getOrInsertFunction(SanCovTracePCName, VoidTy);
489 SanCovTracePCGuard =
490 M.getOrInsertFunction(SanCovTracePCGuardName, VoidTy, Int32PtrTy);
491
492 for (auto &F : M)
493 instrumentFunction(F, DTCallback, PDTCallback);
494
495 Function *Ctor = nullptr;
496
497 if (FunctionGuardArray)
498 Ctor = CreateInitCallsForSections(M, SanCovModuleCtorTracePcGuardName,
501 if (Function8bitCounterArray)
502 Ctor = CreateInitCallsForSections(M, SanCovModuleCtor8bitCountersName,
505 if (FunctionBoolArray) {
506 Ctor = CreateInitCallsForSections(M, SanCovModuleCtorBoolFlagName,
509 }
510 if (Ctor && Options.PCTable) {
511 auto SecStartEnd = CreateSecStartEnd(M, SanCovPCsSectionName, IntptrTy);
513 M, SanCovPCsInitName, {IntptrPtrTy, IntptrPtrTy});
514 IRBuilder<> IRBCtor(Ctor->getEntryBlock().getTerminator());
515 IRBCtor.CreateCall(InitFunction, {SecStartEnd.first, SecStartEnd.second});
516 }
517
518 if (Ctor && Options.CollectControlFlow) {
519 auto SecStartEnd = CreateSecStartEnd(M, SanCovCFsSectionName, IntptrTy);
521 M, SanCovCFsInitName, {IntptrPtrTy, IntptrPtrTy});
522 IRBuilder<> IRBCtor(Ctor->getEntryBlock().getTerminator());
523 IRBCtor.CreateCall(InitFunction, {SecStartEnd.first, SecStartEnd.second});
524 }
525
526 appendToUsed(M, GlobalsToAppendToUsed);
527 appendToCompilerUsed(M, GlobalsToAppendToCompilerUsed);
528 return true;
529}
530
531// True if block has successors and it dominates all of them.
532static bool isFullDominator(const BasicBlock *BB, const DominatorTree *DT) {
533 if (succ_empty(BB))
534 return false;
535
536 return llvm::all_of(successors(BB), [&](const BasicBlock *SUCC) {
537 return DT->dominates(BB, SUCC);
538 });
539}
540
541// True if block has predecessors and it postdominates all of them.
542static bool isFullPostDominator(const BasicBlock *BB,
543 const PostDominatorTree *PDT) {
544 if (pred_empty(BB))
545 return false;
546
547 return llvm::all_of(predecessors(BB), [&](const BasicBlock *PRED) {
548 return PDT->dominates(BB, PRED);
549 });
550}
551
552static bool shouldInstrumentBlock(const Function &F, const BasicBlock *BB,
553 const DominatorTree *DT,
554 const PostDominatorTree *PDT,
556 // Don't insert coverage for blocks containing nothing but unreachable: we
557 // will never call __sanitizer_cov() for them, so counting them in
558 // NumberOfInstrumentedBlocks() might complicate calculation of code coverage
559 // percentage. Also, unreachable instructions frequently have no debug
560 // locations.
561 if (isa<UnreachableInst>(BB->getFirstNonPHIOrDbgOrLifetime()))
562 return false;
563
564 // Don't insert coverage into blocks without a valid insertion point
565 // (catchswitch blocks).
566 if (BB->getFirstInsertionPt() == BB->end())
567 return false;
568
569 if (Options.NoPrune || &F.getEntryBlock() == BB)
570 return true;
571
573 &F.getEntryBlock() != BB)
574 return false;
575
576 // Do not instrument full dominators, or full post-dominators with multiple
577 // predecessors.
578 return !isFullDominator(BB, DT)
579 && !(isFullPostDominator(BB, PDT) && !BB->getSinglePredecessor());
580}
581
582
583// Returns true iff From->To is a backedge.
584// A twist here is that we treat From->To as a backedge if
585// * To dominates From or
586// * To->UniqueSuccessor dominates From
588 const DominatorTree *DT) {
589 if (DT->dominates(To, From))
590 return true;
591 if (auto Next = To->getUniqueSuccessor())
592 if (DT->dominates(Next, From))
593 return true;
594 return false;
595}
596
597// Prunes uninteresting Cmp instrumentation:
598// * CMP instructions that feed into loop backedge branch.
599//
600// Note that Cmp pruning is controlled by the same flag as the
601// BB pruning.
602static bool IsInterestingCmp(ICmpInst *CMP, const DominatorTree *DT,
604 if (!Options.NoPrune)
605 if (CMP->hasOneUse())
606 if (auto BR = dyn_cast<BranchInst>(CMP->user_back()))
607 for (BasicBlock *B : BR->successors())
608 if (IsBackEdge(BR->getParent(), B, DT))
609 return false;
610 return true;
611}
612
613void ModuleSanitizerCoverage::instrumentFunction(
614 Function &F, DomTreeCallback DTCallback, PostDomTreeCallback PDTCallback) {
615 if (F.empty())
616 return;
617 if (F.getName().find(".module_ctor") != std::string::npos)
618 return; // Should not instrument sanitizer init functions.
619 if (F.getName().startswith("__sanitizer_"))
620 return; // Don't instrument __sanitizer_* callbacks.
621 // Don't touch available_externally functions, their actual body is elewhere.
622 if (F.getLinkage() == GlobalValue::AvailableExternallyLinkage)
623 return;
624 // Don't instrument MSVC CRT configuration helpers. They may run before normal
625 // initialization.
626 if (F.getName() == "__local_stdio_printf_options" ||
627 F.getName() == "__local_stdio_scanf_options")
628 return;
629 if (isa<UnreachableInst>(F.getEntryBlock().getTerminator()))
630 return;
631 // Don't instrument functions using SEH for now. Splitting basic blocks like
632 // we do for coverage breaks WinEHPrepare.
633 // FIXME: Remove this when SEH no longer uses landingpad pattern matching.
634 if (F.hasPersonalityFn() &&
636 return;
637 if (Allowlist && !Allowlist->inSection("coverage", "fun", F.getName()))
638 return;
639 if (Blocklist && Blocklist->inSection("coverage", "fun", F.getName()))
640 return;
641 if (F.hasFnAttribute(Attribute::NoSanitizeCoverage))
642 return;
644 SplitAllCriticalEdges(F, CriticalEdgeSplittingOptions().setIgnoreUnreachableDests());
646 SmallVector<BasicBlock *, 16> BlocksToInstrument;
647 SmallVector<Instruction *, 8> CmpTraceTargets;
648 SmallVector<Instruction *, 8> SwitchTraceTargets;
649 SmallVector<BinaryOperator *, 8> DivTraceTargets;
653
654 const DominatorTree *DT = DTCallback(F);
655 const PostDominatorTree *PDT = PDTCallback(F);
656 bool IsLeafFunc = true;
657
658 for (auto &BB : F) {
659 if (shouldInstrumentBlock(F, &BB, DT, PDT, Options))
660 BlocksToInstrument.push_back(&BB);
661 for (auto &Inst : BB) {
662 if (Options.IndirectCalls) {
663 CallBase *CB = dyn_cast<CallBase>(&Inst);
664 if (CB && CB->isIndirectCall())
665 IndirCalls.push_back(&Inst);
666 }
667 if (Options.TraceCmp) {
668 if (ICmpInst *CMP = dyn_cast<ICmpInst>(&Inst))
669 if (IsInterestingCmp(CMP, DT, Options))
670 CmpTraceTargets.push_back(&Inst);
671 if (isa<SwitchInst>(&Inst))
672 SwitchTraceTargets.push_back(&Inst);
673 }
674 if (Options.TraceDiv)
675 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(&Inst))
676 if (BO->getOpcode() == Instruction::SDiv ||
677 BO->getOpcode() == Instruction::UDiv)
678 DivTraceTargets.push_back(BO);
679 if (Options.TraceGep)
680 if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(&Inst))
681 GepTraceTargets.push_back(GEP);
682 if (Options.TraceLoads)
683 if (LoadInst *LI = dyn_cast<LoadInst>(&Inst))
684 Loads.push_back(LI);
685 if (Options.TraceStores)
686 if (StoreInst *SI = dyn_cast<StoreInst>(&Inst))
687 Stores.push_back(SI);
688 if (Options.StackDepth)
689 if (isa<InvokeInst>(Inst) ||
690 (isa<CallInst>(Inst) && !isa<IntrinsicInst>(Inst)))
691 IsLeafFunc = false;
692 }
693 }
694
695 if (Options.CollectControlFlow)
696 createFunctionControlFlow(F);
697
698 InjectCoverage(F, BlocksToInstrument, IsLeafFunc);
699 InjectCoverageForIndirectCalls(F, IndirCalls);
700 InjectTraceForCmp(F, CmpTraceTargets);
701 InjectTraceForSwitch(F, SwitchTraceTargets);
702 InjectTraceForDiv(F, DivTraceTargets);
703 InjectTraceForGep(F, GepTraceTargets);
704 InjectTraceForLoadsAndStores(F, Loads, Stores);
705}
706
707GlobalVariable *ModuleSanitizerCoverage::CreateFunctionLocalArrayInSection(
708 size_t NumElements, Function &F, Type *Ty, const char *Section) {
709 ArrayType *ArrayTy = ArrayType::get(Ty, NumElements);
710 auto Array = new GlobalVariable(
711 *CurModule, ArrayTy, false, GlobalVariable::PrivateLinkage,
712 Constant::getNullValue(ArrayTy), "__sancov_gen_");
713
714 if (TargetTriple.supportsCOMDAT() &&
715 (TargetTriple.isOSBinFormatELF() || !F.isInterposable()))
716 if (auto Comdat = getOrCreateFunctionComdat(F, TargetTriple))
717 Array->setComdat(Comdat);
718 Array->setSection(getSectionName(Section));
719 Array->setAlignment(Align(DL->getTypeStoreSize(Ty).getFixedValue()));
720
721 // sancov_pcs parallels the other metadata section(s). Optimizers (e.g.
722 // GlobalOpt/ConstantMerge) may not discard sancov_pcs and the other
723 // section(s) as a unit, so we conservatively retain all unconditionally in
724 // the compiler.
725 //
726 // With comdat (COFF/ELF), the linker can guarantee the associated sections
727 // will be retained or discarded as a unit, so llvm.compiler.used is
728 // sufficient. Otherwise, conservatively make all of them retained by the
729 // linker.
730 if (Array->hasComdat())
731 GlobalsToAppendToCompilerUsed.push_back(Array);
732 else
733 GlobalsToAppendToUsed.push_back(Array);
734
735 return Array;
736}
737
739ModuleSanitizerCoverage::CreatePCArray(Function &F,
740 ArrayRef<BasicBlock *> AllBlocks) {
741 size_t N = AllBlocks.size();
742 assert(N);
744 IRBuilder<> IRB(&*F.getEntryBlock().getFirstInsertionPt());
745 for (size_t i = 0; i < N; i++) {
746 if (&F.getEntryBlock() == AllBlocks[i]) {
747 PCs.push_back((Constant *)IRB.CreatePointerCast(&F, IntptrPtrTy));
748 PCs.push_back((Constant *)IRB.CreateIntToPtr(
749 ConstantInt::get(IntptrTy, 1), IntptrPtrTy));
750 } else {
751 PCs.push_back((Constant *)IRB.CreatePointerCast(
752 BlockAddress::get(AllBlocks[i]), IntptrPtrTy));
753 PCs.push_back(Constant::getNullValue(IntptrPtrTy));
754 }
755 }
756 auto *PCArray = CreateFunctionLocalArrayInSection(N * 2, F, IntptrPtrTy,
758 PCArray->setInitializer(
759 ConstantArray::get(ArrayType::get(IntptrPtrTy, N * 2), PCs));
760 PCArray->setConstant(true);
761
762 return PCArray;
763}
764
765void ModuleSanitizerCoverage::CreateFunctionLocalArrays(
766 Function &F, ArrayRef<BasicBlock *> AllBlocks) {
767 if (Options.TracePCGuard)
768 FunctionGuardArray = CreateFunctionLocalArrayInSection(
769 AllBlocks.size(), F, Int32Ty, SanCovGuardsSectionName);
770
771 if (Options.Inline8bitCounters)
772 Function8bitCounterArray = CreateFunctionLocalArrayInSection(
773 AllBlocks.size(), F, Int8Ty, SanCovCountersSectionName);
774 if (Options.InlineBoolFlag)
775 FunctionBoolArray = CreateFunctionLocalArrayInSection(
776 AllBlocks.size(), F, Int1Ty, SanCovBoolFlagSectionName);
777
778 if (Options.PCTable)
779 FunctionPCsArray = CreatePCArray(F, AllBlocks);
780}
781
782bool ModuleSanitizerCoverage::InjectCoverage(Function &F,
783 ArrayRef<BasicBlock *> AllBlocks,
784 bool IsLeafFunc) {
785 if (AllBlocks.empty()) return false;
786 CreateFunctionLocalArrays(F, AllBlocks);
787 for (size_t i = 0, N = AllBlocks.size(); i < N; i++)
788 InjectCoverageAtBlock(F, *AllBlocks[i], i, IsLeafFunc);
789 return true;
790}
791
792// On every indirect call we call a run-time function
793// __sanitizer_cov_indir_call* with two parameters:
794// - callee address,
795// - global cache array that contains CacheSize pointers (zero-initialized).
796// The cache is used to speed up recording the caller-callee pairs.
797// The address of the caller is passed implicitly via caller PC.
798// CacheSize is encoded in the name of the run-time function.
799void ModuleSanitizerCoverage::InjectCoverageForIndirectCalls(
800 Function &F, ArrayRef<Instruction *> IndirCalls) {
801 if (IndirCalls.empty())
802 return;
803 assert(Options.TracePC || Options.TracePCGuard ||
804 Options.Inline8bitCounters || Options.InlineBoolFlag);
805 for (auto *I : IndirCalls) {
806 IRBuilder<> IRB(I);
807 CallBase &CB = cast<CallBase>(*I);
809 if (isa<InlineAsm>(Callee))
810 continue;
811 IRB.CreateCall(SanCovTracePCIndir, IRB.CreatePointerCast(Callee, IntptrTy));
812 }
813}
814
815// For every switch statement we insert a call:
816// __sanitizer_cov_trace_switch(CondValue,
817// {NumCases, ValueSizeInBits, Case0Value, Case1Value, Case2Value, ... })
818
819void ModuleSanitizerCoverage::InjectTraceForSwitch(
820 Function &, ArrayRef<Instruction *> SwitchTraceTargets) {
821 for (auto *I : SwitchTraceTargets) {
822 if (SwitchInst *SI = dyn_cast<SwitchInst>(I)) {
823 IRBuilder<> IRB(I);
824 SmallVector<Constant *, 16> Initializers;
825 Value *Cond = SI->getCondition();
826 if (Cond->getType()->getScalarSizeInBits() >
827 Int64Ty->getScalarSizeInBits())
828 continue;
829 Initializers.push_back(ConstantInt::get(Int64Ty, SI->getNumCases()));
830 Initializers.push_back(
831 ConstantInt::get(Int64Ty, Cond->getType()->getScalarSizeInBits()));
832 if (Cond->getType()->getScalarSizeInBits() <
833 Int64Ty->getScalarSizeInBits())
834 Cond = IRB.CreateIntCast(Cond, Int64Ty, false);
835 for (auto It : SI->cases()) {
836 Constant *C = It.getCaseValue();
837 if (C->getType()->getScalarSizeInBits() <
838 Int64Ty->getScalarSizeInBits())
839 C = ConstantExpr::getCast(CastInst::ZExt, It.getCaseValue(), Int64Ty);
840 Initializers.push_back(C);
841 }
842 llvm::sort(drop_begin(Initializers, 2),
843 [](const Constant *A, const Constant *B) {
844 return cast<ConstantInt>(A)->getLimitedValue() <
845 cast<ConstantInt>(B)->getLimitedValue();
846 });
847 ArrayType *ArrayOfInt64Ty = ArrayType::get(Int64Ty, Initializers.size());
849 *CurModule, ArrayOfInt64Ty, false, GlobalVariable::InternalLinkage,
850 ConstantArray::get(ArrayOfInt64Ty, Initializers),
851 "__sancov_gen_cov_switch_values");
852 IRB.CreateCall(SanCovTraceSwitchFunction,
853 {Cond, IRB.CreatePointerCast(GV, Int64PtrTy)});
854 }
855 }
856}
857
858void ModuleSanitizerCoverage::InjectTraceForDiv(
859 Function &, ArrayRef<BinaryOperator *> DivTraceTargets) {
860 for (auto *BO : DivTraceTargets) {
861 IRBuilder<> IRB(BO);
862 Value *A1 = BO->getOperand(1);
863 if (isa<ConstantInt>(A1)) continue;
864 if (!A1->getType()->isIntegerTy())
865 continue;
866 uint64_t TypeSize = DL->getTypeStoreSizeInBits(A1->getType());
867 int CallbackIdx = TypeSize == 32 ? 0 :
868 TypeSize == 64 ? 1 : -1;
869 if (CallbackIdx < 0) continue;
870 auto Ty = Type::getIntNTy(*C, TypeSize);
871 IRB.CreateCall(SanCovTraceDivFunction[CallbackIdx],
872 {IRB.CreateIntCast(A1, Ty, true)});
873 }
874}
875
876void ModuleSanitizerCoverage::InjectTraceForGep(
877 Function &, ArrayRef<GetElementPtrInst *> GepTraceTargets) {
878 for (auto *GEP : GepTraceTargets) {
879 IRBuilder<> IRB(GEP);
880 for (Use &Idx : GEP->indices())
881 if (!isa<ConstantInt>(Idx) && Idx->getType()->isIntegerTy())
882 IRB.CreateCall(SanCovTraceGepFunction,
883 {IRB.CreateIntCast(Idx, IntptrTy, true)});
884 }
885}
886
887void ModuleSanitizerCoverage::InjectTraceForLoadsAndStores(
889 auto CallbackIdx = [&](Type *ElementTy) -> int {
890 uint64_t TypeSize = DL->getTypeStoreSizeInBits(ElementTy);
891 return TypeSize == 8 ? 0
892 : TypeSize == 16 ? 1
893 : TypeSize == 32 ? 2
894 : TypeSize == 64 ? 3
895 : TypeSize == 128 ? 4
896 : -1;
897 };
898 Type *PointerType[5] = {Int8PtrTy, Int16PtrTy, Int32PtrTy, Int64PtrTy,
899 Int128PtrTy};
900 for (auto *LI : Loads) {
901 IRBuilder<> IRB(LI);
902 auto Ptr = LI->getPointerOperand();
903 int Idx = CallbackIdx(LI->getType());
904 if (Idx < 0)
905 continue;
906 IRB.CreateCall(SanCovLoadFunction[Idx],
907 IRB.CreatePointerCast(Ptr, PointerType[Idx]));
908 }
909 for (auto *SI : Stores) {
910 IRBuilder<> IRB(SI);
911 auto Ptr = SI->getPointerOperand();
912 int Idx = CallbackIdx(SI->getValueOperand()->getType());
913 if (Idx < 0)
914 continue;
915 IRB.CreateCall(SanCovStoreFunction[Idx],
916 IRB.CreatePointerCast(Ptr, PointerType[Idx]));
917 }
918}
919
920void ModuleSanitizerCoverage::InjectTraceForCmp(
921 Function &, ArrayRef<Instruction *> CmpTraceTargets) {
922 for (auto *I : CmpTraceTargets) {
923 if (ICmpInst *ICMP = dyn_cast<ICmpInst>(I)) {
924 IRBuilder<> IRB(ICMP);
925 Value *A0 = ICMP->getOperand(0);
926 Value *A1 = ICMP->getOperand(1);
927 if (!A0->getType()->isIntegerTy())
928 continue;
929 uint64_t TypeSize = DL->getTypeStoreSizeInBits(A0->getType());
930 int CallbackIdx = TypeSize == 8 ? 0 :
931 TypeSize == 16 ? 1 :
932 TypeSize == 32 ? 2 :
933 TypeSize == 64 ? 3 : -1;
934 if (CallbackIdx < 0) continue;
935 // __sanitizer_cov_trace_cmp((type_size << 32) | predicate, A0, A1);
936 auto CallbackFunc = SanCovTraceCmpFunction[CallbackIdx];
937 bool FirstIsConst = isa<ConstantInt>(A0);
938 bool SecondIsConst = isa<ConstantInt>(A1);
939 // If both are const, then we don't need such a comparison.
940 if (FirstIsConst && SecondIsConst) continue;
941 // If only one is const, then make it the first callback argument.
942 if (FirstIsConst || SecondIsConst) {
943 CallbackFunc = SanCovTraceConstCmpFunction[CallbackIdx];
944 if (SecondIsConst)
945 std::swap(A0, A1);
946 }
947
948 auto Ty = Type::getIntNTy(*C, TypeSize);
949 IRB.CreateCall(CallbackFunc, {IRB.CreateIntCast(A0, Ty, true),
950 IRB.CreateIntCast(A1, Ty, true)});
951 }
952 }
953}
954
955void ModuleSanitizerCoverage::InjectCoverageAtBlock(Function &F, BasicBlock &BB,
956 size_t Idx,
957 bool IsLeafFunc) {
959 bool IsEntryBB = &BB == &F.getEntryBlock();
960 DebugLoc EntryLoc;
961 if (IsEntryBB) {
962 if (auto SP = F.getSubprogram())
963 EntryLoc = DILocation::get(SP->getContext(), SP->getScopeLine(), 0, SP);
964 // Keep static allocas and llvm.localescape calls in the entry block. Even
965 // if we aren't splitting the block, it's nice for allocas to be before
966 // calls.
967 IP = PrepareToSplitEntryBlock(BB, IP);
968 }
969
970 InstrumentationIRBuilder IRB(&*IP);
971 if (EntryLoc)
972 IRB.SetCurrentDebugLocation(EntryLoc);
973 if (Options.TracePC) {
974 IRB.CreateCall(SanCovTracePC)
975 ->setCannotMerge(); // gets the PC using GET_CALLER_PC.
976 }
977 if (Options.TracePCGuard) {
978 auto GuardPtr = IRB.CreateIntToPtr(
979 IRB.CreateAdd(IRB.CreatePointerCast(FunctionGuardArray, IntptrTy),
980 ConstantInt::get(IntptrTy, Idx * 4)),
981 Int32PtrTy);
982 IRB.CreateCall(SanCovTracePCGuard, GuardPtr)->setCannotMerge();
983 }
984 if (Options.Inline8bitCounters) {
985 auto CounterPtr = IRB.CreateGEP(
986 Function8bitCounterArray->getValueType(), Function8bitCounterArray,
987 {ConstantInt::get(IntptrTy, 0), ConstantInt::get(IntptrTy, Idx)});
988 auto Load = IRB.CreateLoad(Int8Ty, CounterPtr);
989 auto Inc = IRB.CreateAdd(Load, ConstantInt::get(Int8Ty, 1));
990 auto Store = IRB.CreateStore(Inc, CounterPtr);
991 Load->setNoSanitizeMetadata();
992 Store->setNoSanitizeMetadata();
993 }
994 if (Options.InlineBoolFlag) {
995 auto FlagPtr = IRB.CreateGEP(
996 FunctionBoolArray->getValueType(), FunctionBoolArray,
997 {ConstantInt::get(IntptrTy, 0), ConstantInt::get(IntptrTy, Idx)});
998 auto Load = IRB.CreateLoad(Int1Ty, FlagPtr);
999 auto ThenTerm =
1000 SplitBlockAndInsertIfThen(IRB.CreateIsNull(Load), &*IP, false);
1001 IRBuilder<> ThenIRB(ThenTerm);
1002 auto Store = ThenIRB.CreateStore(ConstantInt::getTrue(Int1Ty), FlagPtr);
1003 Load->setNoSanitizeMetadata();
1004 Store->setNoSanitizeMetadata();
1005 }
1006 if (Options.StackDepth && IsEntryBB && !IsLeafFunc) {
1007 // Check stack depth. If it's the deepest so far, record it.
1008 Module *M = F.getParent();
1009 Function *GetFrameAddr = Intrinsic::getDeclaration(
1010 M, Intrinsic::frameaddress,
1011 IRB.getInt8PtrTy(M->getDataLayout().getAllocaAddrSpace()));
1012 auto FrameAddrPtr =
1013 IRB.CreateCall(GetFrameAddr, {Constant::getNullValue(Int32Ty)});
1014 auto FrameAddrInt = IRB.CreatePtrToInt(FrameAddrPtr, IntptrTy);
1015 auto LowestStack = IRB.CreateLoad(IntptrTy, SanCovLowestStack);
1016 auto IsStackLower = IRB.CreateICmpULT(FrameAddrInt, LowestStack);
1017 auto ThenTerm = SplitBlockAndInsertIfThen(IsStackLower, &*IP, false);
1018 IRBuilder<> ThenIRB(ThenTerm);
1019 auto Store = ThenIRB.CreateStore(FrameAddrInt, SanCovLowestStack);
1020 LowestStack->setNoSanitizeMetadata();
1021 Store->setNoSanitizeMetadata();
1022 }
1023}
1024
1025std::string
1026ModuleSanitizerCoverage::getSectionName(const std::string &Section) const {
1027 if (TargetTriple.isOSBinFormatCOFF()) {
1028 if (Section == SanCovCountersSectionName)
1029 return ".SCOV$CM";
1030 if (Section == SanCovBoolFlagSectionName)
1031 return ".SCOV$BM";
1032 if (Section == SanCovPCsSectionName)
1033 return ".SCOVP$M";
1034 return ".SCOV$GM"; // For SanCovGuardsSectionName.
1035 }
1036 if (TargetTriple.isOSBinFormatMachO())
1037 return "__DATA,__" + Section;
1038 return "__" + Section;
1039}
1040
1041std::string
1042ModuleSanitizerCoverage::getSectionStart(const std::string &Section) const {
1043 if (TargetTriple.isOSBinFormatMachO())
1044 return "\1section$start$__DATA$__" + Section;
1045 return "__start___" + Section;
1046}
1047
1048std::string
1049ModuleSanitizerCoverage::getSectionEnd(const std::string &Section) const {
1050 if (TargetTriple.isOSBinFormatMachO())
1051 return "\1section$end$__DATA$__" + Section;
1052 return "__stop___" + Section;
1053}
1054
1055void ModuleSanitizerCoverage::createFunctionControlFlow(Function &F) {
1057 IRBuilder<> IRB(&*F.getEntryBlock().getFirstInsertionPt());
1058
1059 for (auto &BB : F) {
1060 // blockaddress can not be used on function's entry block.
1061 if (&BB == &F.getEntryBlock())
1062 CFs.push_back((Constant *)IRB.CreatePointerCast(&F, IntptrPtrTy));
1063 else
1064 CFs.push_back((Constant *)IRB.CreatePointerCast(BlockAddress::get(&BB),
1065 IntptrPtrTy));
1066
1067 for (auto SuccBB : successors(&BB)) {
1068 assert(SuccBB != &F.getEntryBlock());
1069 CFs.push_back((Constant *)IRB.CreatePointerCast(BlockAddress::get(SuccBB),
1070 IntptrPtrTy));
1071 }
1072
1073 CFs.push_back((Constant *)Constant::getNullValue(IntptrPtrTy));
1074
1075 for (auto &Inst : BB) {
1076 if (CallBase *CB = dyn_cast<CallBase>(&Inst)) {
1077 if (CB->isIndirectCall()) {
1078 // TODO(navidem): handle indirect calls, for now mark its existence.
1079 CFs.push_back((Constant *)IRB.CreateIntToPtr(
1080 ConstantInt::get(IntptrTy, -1), IntptrPtrTy));
1081 } else {
1082 auto CalledF = CB->getCalledFunction();
1083 if (CalledF && !CalledF->isIntrinsic())
1084 CFs.push_back(
1085 (Constant *)IRB.CreatePointerCast(CalledF, IntptrPtrTy));
1086 }
1087 }
1088 }
1089
1090 CFs.push_back((Constant *)Constant::getNullValue(IntptrPtrTy));
1091 }
1092
1093 FunctionCFsArray = CreateFunctionLocalArrayInSection(
1094 CFs.size(), F, IntptrPtrTy, SanCovCFsSectionName);
1095 FunctionCFsArray->setInitializer(
1096 ConstantArray::get(ArrayType::get(IntptrPtrTy, CFs.size()), CFs));
1097 FunctionCFsArray->setConstant(true);
1098}
MachineBasicBlock MachineBasicBlock::iterator DebugLoc DL
amdgpu Simplify well known AMD library false FunctionCallee Callee
SmallVector< MachineOperand, 4 > Cond
BlockVerifier::State From
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
static GCRegistry::Add< ErlangGC > A("erlang", "erlang-compatible garbage collector")
Returns the sub type a function will return at a given Idx Should correspond to the result type of an ExtractValue instruction executed with just that one unsigned Idx
This is the interface for a simple mod/ref and alias analysis over globals.
Hexagon Common GEP
static LVOptions Options
Definition: LVOptions.cpp:25
#define F(x, y, z)
Definition: MD5.cpp:55
#define I(x, y, z)
Definition: MD5.cpp:58
Module.h This file contains the declarations for the Module class.
IntegerType * Int32Ty
static cl::opt< bool > SplitAllCriticalEdges("phi-elim-split-all-critical-edges", cl::init(false), cl::Hidden, cl::desc("Split all critical edges during " "PHI elimination"))
const char LLVMTargetMachineRef LLVMPassBuilderOptionsRef Options
FunctionAnalysisManager FAM
ModuleAnalysisManager MAM
@ SI
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
static cl::opt< bool > ClCreatePCTable("sanitizer-coverage-pc-table", cl::desc("create a static PC table"), cl::Hidden, cl::init(false))
const char SanCovCFsSectionName[]
static cl::opt< bool > ClStoreTracing("sanitizer-coverage-trace-stores", cl::desc("Tracing of store instructions"), cl::Hidden, cl::init(false))
static cl::opt< bool > ClInline8bitCounters("sanitizer-coverage-inline-8bit-counters", cl::desc("increments 8-bit counter for every edge"), cl::Hidden, cl::init(false))
const char SanCovTraceConstCmp4[]
const char SanCovBoolFlagSectionName[]
static bool IsBackEdge(BasicBlock *From, BasicBlock *To, const DominatorTree *DT)
static cl::opt< bool > ClCollectCF("sanitizer-coverage-control-flow", cl::desc("collect control flow for each function"), cl::Hidden, cl::init(false))
const char SanCov8bitCountersInitName[]
static cl::opt< bool > ClInlineBoolFlag("sanitizer-coverage-inline-bool-flag", cl::desc("sets a boolean flag for every edge"), cl::Hidden, cl::init(false))
static cl::opt< bool > ClLoadTracing("sanitizer-coverage-trace-loads", cl::desc("Tracing of load instructions"), cl::Hidden, cl::init(false))
const char SanCovLoad8[]
static bool isFullPostDominator(const BasicBlock *BB, const PostDominatorTree *PDT)
const char SanCovTraceSwitchName[]
const char SanCovTraceCmp1[]
const char SanCovModuleCtorTracePcGuardName[]
static cl::opt< bool > ClCMPTracing("sanitizer-coverage-trace-compares", cl::desc("Tracing of CMP and similar instructions"), cl::Hidden, cl::init(false))
const char SanCovCountersSectionName[]
const char SanCovPCsInitName[]
const char SanCovTracePCGuardName[]
const char SanCovModuleCtor8bitCountersName[]
const char SanCovTracePCGuardInitName[]
const char SanCovTraceDiv4[]
static const uint64_t SanCtorAndDtorPriority
const char SanCovBoolFlagInitName[]
static cl::opt< bool > ClStackDepth("sanitizer-coverage-stack-depth", cl::desc("max stack depth tracing"), cl::Hidden, cl::init(false))
const char SanCovTraceGep[]
static cl::opt< bool > ClTracePC("sanitizer-coverage-trace-pc", cl::desc("Experimental pc tracing"), cl::Hidden, cl::init(false))
const char SanCovLoad16[]
const char SanCovTraceConstCmp8[]
const char SanCovGuardsSectionName[]
const char SanCovStore1[]
const char SanCovTraceConstCmp2[]
const char SanCovTraceConstCmp1[]
static bool shouldInstrumentBlock(const Function &F, const BasicBlock *BB, const DominatorTree *DT, const PostDominatorTree *PDT, const SanitizerCoverageOptions &Options)
static cl::opt< bool > ClTracePCGuard("sanitizer-coverage-trace-pc-guard", cl::desc("pc tracing with a guard"), cl::Hidden, cl::init(false))
const char SanCovTraceDiv8[]
const char SanCovLoad4[]
const char SanCovCFsInitName[]
const char SanCovStore2[]
static cl::opt< bool > ClPruneBlocks("sanitizer-coverage-prune-blocks", cl::desc("Reduce the number of instrumented blocks"), cl::Hidden, cl::init(true))
static cl::opt< int > ClCoverageLevel("sanitizer-coverage-level", cl::desc("Sanitizer Coverage. 0: none, 1: entry block, 2: all blocks, " "3: all blocks and critical edges"), cl::Hidden, cl::init(0))
const char SanCovPCsSectionName[]
const char SanCovLoad1[]
const char SanCovTraceCmp8[]
const char SanCovStore16[]
const char SanCovModuleCtorBoolFlagName[]
static bool IsInterestingCmp(ICmpInst *CMP, const DominatorTree *DT, const SanitizerCoverageOptions &Options)
const char SanCovTraceCmp2[]
const char SanCovStore8[]
const char SanCovTracePCName[]
const char SanCovStore4[]
const char SanCovLoad2[]
static bool isFullDominator(const BasicBlock *BB, const DominatorTree *DT)
const char SanCovTraceCmp4[]
const char SanCovLowestStackName[]
static cl::opt< bool > ClDIVTracing("sanitizer-coverage-trace-divs", cl::desc("Tracing of DIV instructions"), cl::Hidden, cl::init(false))
const char SanCovTracePCIndirName[]
static cl::opt< bool > ClGEPTracing("sanitizer-coverage-trace-geps", cl::desc("Tracing of GEP instructions"), cl::Hidden, cl::init(false))
This file defines the SmallVector class.
Defines the virtual file system interface vfs::FileSystem.
A container for analyses that lazily runs them and caches their results.
Definition: PassManager.h:620
PassT::Result & getResult(IRUnitT &IR, ExtraArgTs... ExtraArgs)
Get the result of an analysis pass for a given IR unit.
Definition: PassManager.h:774
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory),...
Definition: ArrayRef.h:41
size_t size() const
size - Get the array size.
Definition: ArrayRef.h:163
bool empty() const
empty - Check if the array is empty.
Definition: ArrayRef.h:158
static ArrayType * get(Type *ElementType, uint64_t NumElements)
This static method is the primary way to construct an ArrayType.
Definition: Type.cpp:708
AttributeList addParamAttribute(LLVMContext &C, unsigned ArgNo, Attribute::AttrKind Kind) const
Add an argument attribute to the list.
Definition: Attributes.h:576
LLVM Basic Block Representation.
Definition: BasicBlock.h:56
iterator end()
Definition: BasicBlock.h:328
const_iterator getFirstInsertionPt() const
Returns an iterator to the first instruction in this block that is suitable for inserting a non-PHI i...
Definition: BasicBlock.cpp:253
const BasicBlock * getUniqueSuccessor() const
Return the successor of this block if it has a unique successor.
Definition: BasicBlock.cpp:330
const BasicBlock * getSinglePredecessor() const
Return the predecessor of this block if it has a single predecessor block.
Definition: BasicBlock.cpp:292
const Instruction * getFirstNonPHIOrDbgOrLifetime(bool SkipPseudoOp=true) const
Returns a pointer to the first instruction in this block that is not a PHINode, a debug intrinsic,...
Definition: BasicBlock.cpp:237
InstListType::iterator iterator
Instruction iterators...
Definition: BasicBlock.h:87
const Instruction * getTerminator() const LLVM_READONLY
Returns the terminator instruction if the block is well formed or null if the block is not well forme...
Definition: BasicBlock.h:127
static BlockAddress * get(Function *F, BasicBlock *BB)
Return a BlockAddress for the specified function and basic block.
Definition: Constants.cpp:1762
Base class for all callable instructions (InvokeInst and CallInst) Holds everything related to callin...
Definition: InstrTypes.h:1190
Function * getCalledFunction() const
Returns the function called, or null if this is an indirect function invocation or the function signa...
Definition: InstrTypes.h:1412
bool isIndirectCall() const
Return true if the callsite is an indirect call.
Value * getCalledOperand() const
Definition: InstrTypes.h:1405
static Constant * get(ArrayType *T, ArrayRef< Constant * > V)
Definition: Constants.cpp:1235
static Constant * getCast(unsigned ops, Constant *C, Type *Ty, bool OnlyIfReduced=false)
Convenience function for getting a Cast operation.
Definition: Constants.cpp:1957
static ConstantInt * getTrue(LLVMContext &Context)
Definition: Constants.cpp:833
static Constant * get(Type *Ty, uint64_t V, bool IsSigned=false)
If Ty is a vector type, return a Constant with a splat of the given value.
Definition: Constants.cpp:888
This is an important base class in LLVM.
Definition: Constant.h:41
static Constant * getAllOnesValue(Type *Ty)
Definition: Constants.cpp:403
static Constant * getNullValue(Type *Ty)
Constructor to create a '0' constant of arbitrary type.
Definition: Constants.cpp:356
A parsed version of the target data layout string in and methods for querying it.
Definition: DataLayout.h:110
A debug info location.
Definition: DebugLoc.h:33
Analysis pass which computes a DominatorTree.
Definition: Dominators.h:279
Concrete subclass of DominatorTreeBase that is used to compute a normal dominator tree.
Definition: Dominators.h:166
bool dominates(const BasicBlock *BB, const Use &U) const
Return true if the (end of the) basic block BB dominates the use U.
Definition: Dominators.cpp:122
A handy container for a FunctionType+Callee-pointer pair, which can be passed around as a single enti...
Definition: DerivedTypes.h:165
const BasicBlock & getEntryBlock() const
Definition: Function.h:745
an instruction for type-safe pointer arithmetic to access elements of arrays and structs
Definition: Instructions.h:940
void setComdat(Comdat *C)
Definition: Globals.cpp:196
void setLinkage(LinkageTypes LT)
Definition: GlobalValue.h:532
@ HiddenVisibility
The GV is hidden.
Definition: GlobalValue.h:64
void setVisibility(VisibilityTypes V)
Definition: GlobalValue.h:250
LinkageTypes
An enumeration for the kinds of linkage for global values.
Definition: GlobalValue.h:47
@ PrivateLinkage
Like Internal, but omit from symbol table.
Definition: GlobalValue.h:56
@ InternalLinkage
Rename collisions when linking (static functions).
Definition: GlobalValue.h:55
@ WeakODRLinkage
Same, but only replaced by something equivalent.
Definition: GlobalValue.h:53
@ ExternalLinkage
Externally visible function.
Definition: GlobalValue.h:48
@ AvailableExternallyLinkage
Available for inspection, not emission.
Definition: GlobalValue.h:49
@ ExternalWeakLinkage
ExternalWeak linkage description.
Definition: GlobalValue.h:57
Analysis pass providing a never-invalidated alias analysis result.
This instruction compares its operands according to the predicate given to the constructor.
This provides a uniform API for creating instructions and inserting them into a basic block: either a...
Definition: IRBuilder.h:2570
An analysis over an "outer" IR unit that provides access to an analysis manager over an "inner" IR un...
Definition: PassManager.h:933
This is an important class for using LLVM in a threaded context.
Definition: LLVMContext.h:67
An instruction for reading from memory.
Definition: Instructions.h:177
static MDTuple * get(LLVMContext &Context, ArrayRef< Metadata * > MDs)
Definition: Metadata.h:1416
A Module instance is used to store all the information related to an LLVM module.
Definition: Module.h:65
static PointerType * getUnqual(Type *ElementType)
This constructs a pointer to an object of the specified type in the default address space (address sp...
Definition: DerivedTypes.h:662
Analysis pass which computes a PostDominatorTree.
PostDominatorTree Class - Concrete subclass of DominatorTree that is used to compute the post-dominat...
bool dominates(const Instruction *I1, const Instruction *I2) const
Return true if I1 dominates I2.
A set of analyses that are preserved following a run of a transformation pass.
Definition: PassManager.h:152
static PreservedAnalyses none()
Convenience factory function for the empty preserved set.
Definition: PassManager.h:155
static PreservedAnalyses all()
Construct a special preserved set that preserves all passes.
Definition: PassManager.h:158
void abandon()
Mark an analysis as abandoned.
Definition: PassManager.h:206
PreservedAnalyses run(Module &M, ModuleAnalysisManager &AM)
size_t size() const
Definition: SmallVector.h:91
void push_back(const T &Elt)
Definition: SmallVector.h:416
This is a 'vector' (really, a variable-sized array), optimized for the case when the array is small.
Definition: SmallVector.h:1200
An instruction for storing to memory.
Definition: Instructions.h:301
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:50
Multiway switch.
Triple - Helper class for working with autoconf configuration names.
Definition: Triple.h:44
The instances of the Type class are immutable: once they are created, they are never changed.
Definition: Type.h:45
static IntegerType * getInt1Ty(LLVMContext &C)
static IntegerType * getIntNTy(LLVMContext &C, unsigned N)
static Type * getVoidTy(LLVMContext &C)
static IntegerType * getInt16Ty(LLVMContext &C)
static IntegerType * getInt8Ty(LLVMContext &C)
static IntegerType * getInt32Ty(LLVMContext &C)
bool isIntegerTy() const
True if this is an instance of IntegerType.
Definition: Type.h:229
A Use represents the edge between a Value definition and its users.
Definition: Use.h:43
LLVM Value Representation.
Definition: Value.h:74
Type * getType() const
All values are typed, get the type of this value.
Definition: Value.h:255
StringRef getName() const
Return a constant reference to the value's name.
Definition: Value.cpp:309
An efficient, type-erasing, non-owning reference to a callable.
@ C
The default llvm calling convention, compatible with C.
Definition: CallingConv.h:34
Function * getDeclaration(Module *M, ID id, ArrayRef< Type * > Tys=std::nullopt)
Create or insert an LLVM Function declaration for an intrinsic, and return it.
Definition: Function.cpp:1465
initializer< Ty > init(const Ty &Val)
Definition: CommandLine.h:445
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
auto drop_begin(T &&RangeOrContainer, size_t N=1)
Return a range covering RangeOrContainer with the first N elements excluded.
Definition: STLExtras.h:413
bool all_of(R &&range, UnaryPredicate P)
Provide wrappers to std::all_of which take ranges instead of having to pass begin/end explicitly.
Definition: STLExtras.h:1819
bool succ_empty(const Instruction *I)
Definition: CFG.h:255
auto successors(const MachineBasicBlock *BB)
Instruction * SplitBlockAndInsertIfThen(Value *Cond, Instruction *SplitBefore, bool Unreachable, MDNode *BranchWeights=nullptr, DomTreeUpdater *DTU=nullptr, LoopInfo *LI=nullptr, BasicBlock *ThenBlock=nullptr)
Split the containing block at the specified instruction - everything before SplitBefore stays in the ...
FunctionCallee declareSanitizerInitFunction(Module &M, StringRef InitName, ArrayRef< Type * > InitArgTypes, bool Weak=false)
std::string getUniqueModuleId(Module *M)
Produce a unique identifier for this module by taking the MD5 sum of the names of the module's strong...
std::pair< Function *, FunctionCallee > createSanitizerCtorAndInitFunctions(Module &M, StringRef CtorName, StringRef InitName, ArrayRef< Type * > InitArgTypes, ArrayRef< Value * > InitArgs, StringRef VersionCheckName=StringRef(), bool Weak=false)
Creates sanitizer constructor function, and calls sanitizer's init function from it.
void sort(IteratorTy Start, IteratorTy End)
Definition: STLExtras.h:1744
EHPersonality classifyEHPersonality(const Value *Pers)
See if the given exception handling personality function is one that we understand.
Comdat * getOrCreateFunctionComdat(Function &F, Triple &T)
void appendToCompilerUsed(Module &M, ArrayRef< GlobalValue * > Values)
Adds global values to the llvm.compiler.used list.
bool isAsynchronousEHPersonality(EHPersonality Pers)
Returns true if this personality function catches asynchronous exceptions.
void appendToGlobalCtors(Module &M, Function *F, int Priority, Constant *Data=nullptr)
Append F to the list of global ctors of module M with the given Priority.
Definition: ModuleUtils.cpp:71
auto predecessors(const MachineBasicBlock *BB)
bool pred_empty(const BasicBlock *BB)
Definition: CFG.h:118
BasicBlock::iterator PrepareToSplitEntryBlock(BasicBlock &BB, BasicBlock::iterator IP)
Instrumentation passes often insert conditional checks into entry blocks.
void appendToUsed(Module &M, ArrayRef< GlobalValue * > Values)
Adds global values to the llvm.used list.
void swap(llvm::BitVector &LHS, llvm::BitVector &RHS)
Implement std::swap in terms of BitVector swap.
Definition: BitVector.h:860
#define N
This struct is a compact representation of a valid (non-zero power of two) alignment.
Definition: Alignment.h:39
Option class for critical edge splitting.
enum llvm::SanitizerCoverageOptions::Type CoverageType