/Users/buildslave/jenkins/sharedspace/clang-stage2-coverage-R@2/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
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1 | | //===-- MemorySanitizer.cpp - detector of uninitialized reads -------------===// |
2 | | // |
3 | | // The LLVM Compiler Infrastructure |
4 | | // |
5 | | // This file is distributed under the University of Illinois Open Source |
6 | | // License. See LICENSE.TXT for details. |
7 | | // |
8 | | //===----------------------------------------------------------------------===// |
9 | | /// \file |
10 | | /// This file is a part of MemorySanitizer, a detector of uninitialized |
11 | | /// reads. |
12 | | /// |
13 | | /// The algorithm of the tool is similar to Memcheck |
14 | | /// (http://goo.gl/QKbem). We associate a few shadow bits with every |
15 | | /// byte of the application memory, poison the shadow of the malloc-ed |
16 | | /// or alloca-ed memory, load the shadow bits on every memory read, |
17 | | /// propagate the shadow bits through some of the arithmetic |
18 | | /// instruction (including MOV), store the shadow bits on every memory |
19 | | /// write, report a bug on some other instructions (e.g. JMP) if the |
20 | | /// associated shadow is poisoned. |
21 | | /// |
22 | | /// But there are differences too. The first and the major one: |
23 | | /// compiler instrumentation instead of binary instrumentation. This |
24 | | /// gives us much better register allocation, possible compiler |
25 | | /// optimizations and a fast start-up. But this brings the major issue |
26 | | /// as well: msan needs to see all program events, including system |
27 | | /// calls and reads/writes in system libraries, so we either need to |
28 | | /// compile *everything* with msan or use a binary translation |
29 | | /// component (e.g. DynamoRIO) to instrument pre-built libraries. |
30 | | /// Another difference from Memcheck is that we use 8 shadow bits per |
31 | | /// byte of application memory and use a direct shadow mapping. This |
32 | | /// greatly simplifies the instrumentation code and avoids races on |
33 | | /// shadow updates (Memcheck is single-threaded so races are not a |
34 | | /// concern there. Memcheck uses 2 shadow bits per byte with a slow |
35 | | /// path storage that uses 8 bits per byte). |
36 | | /// |
37 | | /// The default value of shadow is 0, which means "clean" (not poisoned). |
38 | | /// |
39 | | /// Every module initializer should call __msan_init to ensure that the |
40 | | /// shadow memory is ready. On error, __msan_warning is called. Since |
41 | | /// parameters and return values may be passed via registers, we have a |
42 | | /// specialized thread-local shadow for return values |
43 | | /// (__msan_retval_tls) and parameters (__msan_param_tls). |
44 | | /// |
45 | | /// Origin tracking. |
46 | | /// |
47 | | /// MemorySanitizer can track origins (allocation points) of all uninitialized |
48 | | /// values. This behavior is controlled with a flag (msan-track-origins) and is |
49 | | /// disabled by default. |
50 | | /// |
51 | | /// Origins are 4-byte values created and interpreted by the runtime library. |
52 | | /// They are stored in a second shadow mapping, one 4-byte value for 4 bytes |
53 | | /// of application memory. Propagation of origins is basically a bunch of |
54 | | /// "select" instructions that pick the origin of a dirty argument, if an |
55 | | /// instruction has one. |
56 | | /// |
57 | | /// Every 4 aligned, consecutive bytes of application memory have one origin |
58 | | /// value associated with them. If these bytes contain uninitialized data |
59 | | /// coming from 2 different allocations, the last store wins. Because of this, |
60 | | /// MemorySanitizer reports can show unrelated origins, but this is unlikely in |
61 | | /// practice. |
62 | | /// |
63 | | /// Origins are meaningless for fully initialized values, so MemorySanitizer |
64 | | /// avoids storing origin to memory when a fully initialized value is stored. |
65 | | /// This way it avoids needless overwritting origin of the 4-byte region on |
66 | | /// a short (i.e. 1 byte) clean store, and it is also good for performance. |
67 | | /// |
68 | | /// Atomic handling. |
69 | | /// |
70 | | /// Ideally, every atomic store of application value should update the |
71 | | /// corresponding shadow location in an atomic way. Unfortunately, atomic store |
72 | | /// of two disjoint locations can not be done without severe slowdown. |
73 | | /// |
74 | | /// Therefore, we implement an approximation that may err on the safe side. |
75 | | /// In this implementation, every atomically accessed location in the program |
76 | | /// may only change from (partially) uninitialized to fully initialized, but |
77 | | /// not the other way around. We load the shadow _after_ the application load, |
78 | | /// and we store the shadow _before_ the app store. Also, we always store clean |
79 | | /// shadow (if the application store is atomic). This way, if the store-load |
80 | | /// pair constitutes a happens-before arc, shadow store and load are correctly |
81 | | /// ordered such that the load will get either the value that was stored, or |
82 | | /// some later value (which is always clean). |
83 | | /// |
84 | | /// This does not work very well with Compare-And-Swap (CAS) and |
85 | | /// Read-Modify-Write (RMW) operations. To follow the above logic, CAS and RMW |
86 | | /// must store the new shadow before the app operation, and load the shadow |
87 | | /// after the app operation. Computers don't work this way. Current |
88 | | /// implementation ignores the load aspect of CAS/RMW, always returning a clean |
89 | | /// value. It implements the store part as a simple atomic store by storing a |
90 | | /// clean shadow. |
91 | | |
92 | | //===----------------------------------------------------------------------===// |
93 | | |
94 | | #include "llvm/ADT/DepthFirstIterator.h" |
95 | | #include "llvm/ADT/SmallString.h" |
96 | | #include "llvm/ADT/SmallVector.h" |
97 | | #include "llvm/ADT/StringExtras.h" |
98 | | #include "llvm/ADT/Triple.h" |
99 | | #include "llvm/IR/DataLayout.h" |
100 | | #include "llvm/IR/Function.h" |
101 | | #include "llvm/IR/IRBuilder.h" |
102 | | #include "llvm/IR/InlineAsm.h" |
103 | | #include "llvm/IR/InstVisitor.h" |
104 | | #include "llvm/IR/IntrinsicInst.h" |
105 | | #include "llvm/IR/LLVMContext.h" |
106 | | #include "llvm/IR/MDBuilder.h" |
107 | | #include "llvm/IR/Module.h" |
108 | | #include "llvm/IR/Type.h" |
109 | | #include "llvm/IR/ValueMap.h" |
110 | | #include "llvm/Support/CommandLine.h" |
111 | | #include "llvm/Support/Debug.h" |
112 | | #include "llvm/Support/raw_ostream.h" |
113 | | #include "llvm/Transforms/Instrumentation.h" |
114 | | #include "llvm/Transforms/Utils/BasicBlockUtils.h" |
115 | | #include "llvm/Transforms/Utils/Local.h" |
116 | | #include "llvm/Transforms/Utils/ModuleUtils.h" |
117 | | |
118 | | using namespace llvm; |
119 | | |
120 | | #define DEBUG_TYPE "msan" |
121 | | |
122 | | static const unsigned kOriginSize = 4; |
123 | | static const unsigned kMinOriginAlignment = 4; |
124 | | static const unsigned kShadowTLSAlignment = 8; |
125 | | |
126 | | // These constants must be kept in sync with the ones in msan.h. |
127 | | static const unsigned kParamTLSSize = 800; |
128 | | static const unsigned kRetvalTLSSize = 800; |
129 | | |
130 | | // Accesses sizes are powers of two: 1, 2, 4, 8. |
131 | | static const size_t kNumberOfAccessSizes = 4; |
132 | | |
133 | | /// \brief Track origins of uninitialized values. |
134 | | /// |
135 | | /// Adds a section to MemorySanitizer report that points to the allocation |
136 | | /// (stack or heap) the uninitialized bits came from originally. |
137 | | static cl::opt<int> ClTrackOrigins("msan-track-origins", |
138 | | cl::desc("Track origins (allocation sites) of poisoned memory"), |
139 | | cl::Hidden, cl::init(0)); |
140 | | static cl::opt<bool> ClKeepGoing("msan-keep-going", |
141 | | cl::desc("keep going after reporting a UMR"), |
142 | | cl::Hidden, cl::init(false)); |
143 | | static cl::opt<bool> ClPoisonStack("msan-poison-stack", |
144 | | cl::desc("poison uninitialized stack variables"), |
145 | | cl::Hidden, cl::init(true)); |
146 | | static cl::opt<bool> ClPoisonStackWithCall("msan-poison-stack-with-call", |
147 | | cl::desc("poison uninitialized stack variables with a call"), |
148 | | cl::Hidden, cl::init(false)); |
149 | | static cl::opt<int> ClPoisonStackPattern("msan-poison-stack-pattern", |
150 | | cl::desc("poison uninitialized stack variables with the given pattern"), |
151 | | cl::Hidden, cl::init(0xff)); |
152 | | static cl::opt<bool> ClPoisonUndef("msan-poison-undef", |
153 | | cl::desc("poison undef temps"), |
154 | | cl::Hidden, cl::init(true)); |
155 | | |
156 | | static cl::opt<bool> ClHandleICmp("msan-handle-icmp", |
157 | | cl::desc("propagate shadow through ICmpEQ and ICmpNE"), |
158 | | cl::Hidden, cl::init(true)); |
159 | | |
160 | | static cl::opt<bool> ClHandleICmpExact("msan-handle-icmp-exact", |
161 | | cl::desc("exact handling of relational integer ICmp"), |
162 | | cl::Hidden, cl::init(false)); |
163 | | |
164 | | // This flag controls whether we check the shadow of the address |
165 | | // operand of load or store. Such bugs are very rare, since load from |
166 | | // a garbage address typically results in SEGV, but still happen |
167 | | // (e.g. only lower bits of address are garbage, or the access happens |
168 | | // early at program startup where malloc-ed memory is more likely to |
169 | | // be zeroed. As of 2012-08-28 this flag adds 20% slowdown. |
170 | | static cl::opt<bool> ClCheckAccessAddress("msan-check-access-address", |
171 | | cl::desc("report accesses through a pointer which has poisoned shadow"), |
172 | | cl::Hidden, cl::init(true)); |
173 | | |
174 | | static cl::opt<bool> ClDumpStrictInstructions("msan-dump-strict-instructions", |
175 | | cl::desc("print out instructions with default strict semantics"), |
176 | | cl::Hidden, cl::init(false)); |
177 | | |
178 | | static cl::opt<int> ClInstrumentationWithCallThreshold( |
179 | | "msan-instrumentation-with-call-threshold", |
180 | | cl::desc( |
181 | | "If the function being instrumented requires more than " |
182 | | "this number of checks and origin stores, use callbacks instead of " |
183 | | "inline checks (-1 means never use callbacks)."), |
184 | | cl::Hidden, cl::init(3500)); |
185 | | |
186 | | // This is an experiment to enable handling of cases where shadow is a non-zero |
187 | | // compile-time constant. For some unexplainable reason they were silently |
188 | | // ignored in the instrumentation. |
189 | | static cl::opt<bool> ClCheckConstantShadow("msan-check-constant-shadow", |
190 | | cl::desc("Insert checks for constant shadow values"), |
191 | | cl::Hidden, cl::init(false)); |
192 | | |
193 | | // This is off by default because of a bug in gold: |
194 | | // https://sourceware.org/bugzilla/show_bug.cgi?id=19002 |
195 | | static cl::opt<bool> ClWithComdat("msan-with-comdat", |
196 | | cl::desc("Place MSan constructors in comdat sections"), |
197 | | cl::Hidden, cl::init(false)); |
198 | | |
199 | | static const char *const kMsanModuleCtorName = "msan.module_ctor"; |
200 | | static const char *const kMsanInitName = "__msan_init"; |
201 | | |
202 | | namespace { |
203 | | |
204 | | // Memory map parameters used in application-to-shadow address calculation. |
205 | | // Offset = (Addr & ~AndMask) ^ XorMask |
206 | | // Shadow = ShadowBase + Offset |
207 | | // Origin = OriginBase + Offset |
208 | | struct MemoryMapParams { |
209 | | uint64_t AndMask; |
210 | | uint64_t XorMask; |
211 | | uint64_t ShadowBase; |
212 | | uint64_t OriginBase; |
213 | | }; |
214 | | |
215 | | struct PlatformMemoryMapParams { |
216 | | const MemoryMapParams *bits32; |
217 | | const MemoryMapParams *bits64; |
218 | | }; |
219 | | |
220 | | // i386 Linux |
221 | | static const MemoryMapParams Linux_I386_MemoryMapParams = { |
222 | | 0x000080000000, // AndMask |
223 | | 0, // XorMask (not used) |
224 | | 0, // ShadowBase (not used) |
225 | | 0x000040000000, // OriginBase |
226 | | }; |
227 | | |
228 | | // x86_64 Linux |
229 | | static const MemoryMapParams Linux_X86_64_MemoryMapParams = { |
230 | | #ifdef MSAN_LINUX_X86_64_OLD_MAPPING |
231 | | 0x400000000000, // AndMask |
232 | | 0, // XorMask (not used) |
233 | | 0, // ShadowBase (not used) |
234 | | 0x200000000000, // OriginBase |
235 | | #else |
236 | | 0, // AndMask (not used) |
237 | | 0x500000000000, // XorMask |
238 | | 0, // ShadowBase (not used) |
239 | | 0x100000000000, // OriginBase |
240 | | #endif |
241 | | }; |
242 | | |
243 | | // mips64 Linux |
244 | | static const MemoryMapParams Linux_MIPS64_MemoryMapParams = { |
245 | | 0, // AndMask (not used) |
246 | | 0x008000000000, // XorMask |
247 | | 0, // ShadowBase (not used) |
248 | | 0x002000000000, // OriginBase |
249 | | }; |
250 | | |
251 | | // ppc64 Linux |
252 | | static const MemoryMapParams Linux_PowerPC64_MemoryMapParams = { |
253 | | 0x200000000000, // AndMask |
254 | | 0x100000000000, // XorMask |
255 | | 0x080000000000, // ShadowBase |
256 | | 0x1C0000000000, // OriginBase |
257 | | }; |
258 | | |
259 | | // aarch64 Linux |
260 | | static const MemoryMapParams Linux_AArch64_MemoryMapParams = { |
261 | | 0, // AndMask (not used) |
262 | | 0x06000000000, // XorMask |
263 | | 0, // ShadowBase (not used) |
264 | | 0x01000000000, // OriginBase |
265 | | }; |
266 | | |
267 | | // i386 FreeBSD |
268 | | static const MemoryMapParams FreeBSD_I386_MemoryMapParams = { |
269 | | 0x000180000000, // AndMask |
270 | | 0x000040000000, // XorMask |
271 | | 0x000020000000, // ShadowBase |
272 | | 0x000700000000, // OriginBase |
273 | | }; |
274 | | |
275 | | // x86_64 FreeBSD |
276 | | static const MemoryMapParams FreeBSD_X86_64_MemoryMapParams = { |
277 | | 0xc00000000000, // AndMask |
278 | | 0x200000000000, // XorMask |
279 | | 0x100000000000, // ShadowBase |
280 | | 0x380000000000, // OriginBase |
281 | | }; |
282 | | |
283 | | static const PlatformMemoryMapParams Linux_X86_MemoryMapParams = { |
284 | | &Linux_I386_MemoryMapParams, |
285 | | &Linux_X86_64_MemoryMapParams, |
286 | | }; |
287 | | |
288 | | static const PlatformMemoryMapParams Linux_MIPS_MemoryMapParams = { |
289 | | nullptr, |
290 | | &Linux_MIPS64_MemoryMapParams, |
291 | | }; |
292 | | |
293 | | static const PlatformMemoryMapParams Linux_PowerPC_MemoryMapParams = { |
294 | | nullptr, |
295 | | &Linux_PowerPC64_MemoryMapParams, |
296 | | }; |
297 | | |
298 | | static const PlatformMemoryMapParams Linux_ARM_MemoryMapParams = { |
299 | | nullptr, |
300 | | &Linux_AArch64_MemoryMapParams, |
301 | | }; |
302 | | |
303 | | static const PlatformMemoryMapParams FreeBSD_X86_MemoryMapParams = { |
304 | | &FreeBSD_I386_MemoryMapParams, |
305 | | &FreeBSD_X86_64_MemoryMapParams, |
306 | | }; |
307 | | |
308 | | /// \brief An instrumentation pass implementing detection of uninitialized |
309 | | /// reads. |
310 | | /// |
311 | | /// MemorySanitizer: instrument the code in module to find |
312 | | /// uninitialized reads. |
313 | | class MemorySanitizer : public FunctionPass { |
314 | | public: |
315 | | MemorySanitizer(int TrackOrigins = 0, bool Recover = false) |
316 | | : FunctionPass(ID), |
317 | | TrackOrigins(std::max(TrackOrigins, (int)ClTrackOrigins)), |
318 | | Recover(Recover || ClKeepGoing), |
319 | 64 | WarningFn(nullptr) {} |
320 | 0 | StringRef getPassName() const override { return "MemorySanitizer"; } |
321 | 64 | void getAnalysisUsage(AnalysisUsage &AU) const override { |
322 | 64 | AU.addRequired<TargetLibraryInfoWrapperPass>(); |
323 | 64 | } |
324 | | bool runOnFunction(Function &F) override; |
325 | | bool doInitialization(Module &M) override; |
326 | | static char ID; // Pass identification, replacement for typeid. |
327 | | |
328 | | private: |
329 | | void initializeCallbacks(Module &M); |
330 | | |
331 | | /// \brief Track origins (allocation points) of uninitialized values. |
332 | | int TrackOrigins; |
333 | | bool Recover; |
334 | | |
335 | | LLVMContext *C; |
336 | | Type *IntptrTy; |
337 | | Type *OriginTy; |
338 | | /// \brief Thread-local shadow storage for function parameters. |
339 | | GlobalVariable *ParamTLS; |
340 | | /// \brief Thread-local origin storage for function parameters. |
341 | | GlobalVariable *ParamOriginTLS; |
342 | | /// \brief Thread-local shadow storage for function return value. |
343 | | GlobalVariable *RetvalTLS; |
344 | | /// \brief Thread-local origin storage for function return value. |
345 | | GlobalVariable *RetvalOriginTLS; |
346 | | /// \brief Thread-local shadow storage for in-register va_arg function |
347 | | /// parameters (x86_64-specific). |
348 | | GlobalVariable *VAArgTLS; |
349 | | /// \brief Thread-local shadow storage for va_arg overflow area |
350 | | /// (x86_64-specific). |
351 | | GlobalVariable *VAArgOverflowSizeTLS; |
352 | | /// \brief Thread-local space used to pass origin value to the UMR reporting |
353 | | /// function. |
354 | | GlobalVariable *OriginTLS; |
355 | | |
356 | | /// \brief The run-time callback to print a warning. |
357 | | Value *WarningFn; |
358 | | // These arrays are indexed by log2(AccessSize). |
359 | | Value *MaybeWarningFn[kNumberOfAccessSizes]; |
360 | | Value *MaybeStoreOriginFn[kNumberOfAccessSizes]; |
361 | | |
362 | | /// \brief Run-time helper that generates a new origin value for a stack |
363 | | /// allocation. |
364 | | Value *MsanSetAllocaOrigin4Fn; |
365 | | /// \brief Run-time helper that poisons stack on function entry. |
366 | | Value *MsanPoisonStackFn; |
367 | | /// \brief Run-time helper that records a store (or any event) of an |
368 | | /// uninitialized value and returns an updated origin id encoding this info. |
369 | | Value *MsanChainOriginFn; |
370 | | /// \brief MSan runtime replacements for memmove, memcpy and memset. |
371 | | Value *MemmoveFn, *MemcpyFn, *MemsetFn; |
372 | | |
373 | | /// \brief Memory map parameters used in application-to-shadow calculation. |
374 | | const MemoryMapParams *MapParams; |
375 | | |
376 | | MDNode *ColdCallWeights; |
377 | | /// \brief Branch weights for origin store. |
378 | | MDNode *OriginStoreWeights; |
379 | | /// \brief An empty volatile inline asm that prevents callback merge. |
380 | | InlineAsm *EmptyAsm; |
381 | | Function *MsanCtorFunction; |
382 | | |
383 | | friend struct MemorySanitizerVisitor; |
384 | | friend struct VarArgAMD64Helper; |
385 | | friend struct VarArgMIPS64Helper; |
386 | | friend struct VarArgAArch64Helper; |
387 | | friend struct VarArgPowerPC64Helper; |
388 | | }; |
389 | | } // anonymous namespace |
390 | | |
391 | | char MemorySanitizer::ID = 0; |
392 | 7.91k | INITIALIZE_PASS_BEGIN7.91k (
|
393 | 7.91k | MemorySanitizer, "msan", |
394 | 7.91k | "MemorySanitizer: detects uninitialized reads.", false, false) |
395 | 7.91k | INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass) |
396 | 7.91k | INITIALIZE_PASS_END( |
397 | | MemorySanitizer, "msan", |
398 | | "MemorySanitizer: detects uninitialized reads.", false, false) |
399 | | |
400 | 16 | FunctionPass *llvm::createMemorySanitizerPass(int TrackOrigins, bool Recover) { |
401 | 16 | return new MemorySanitizer(TrackOrigins, Recover); |
402 | 16 | } |
403 | | |
404 | | /// \brief Create a non-const global initialized with the given string. |
405 | | /// |
406 | | /// Creates a writable global for Str so that we can pass it to the |
407 | | /// run-time lib. Runtime uses first 4 bytes of the string to store the |
408 | | /// frame ID, so the string needs to be mutable. |
409 | | static GlobalVariable *createPrivateNonConstGlobalForString(Module &M, |
410 | 13 | StringRef Str) { |
411 | 13 | Constant *StrConst = ConstantDataArray::getString(M.getContext(), Str); |
412 | 13 | return new GlobalVariable(M, StrConst->getType(), /*isConstant=*/false, |
413 | 13 | GlobalValue::PrivateLinkage, StrConst, ""); |
414 | 13 | } |
415 | | |
416 | | /// \brief Insert extern declaration of runtime-provided functions and globals. |
417 | 373 | void MemorySanitizer::initializeCallbacks(Module &M) { |
418 | 373 | // Only do this once. |
419 | 373 | if (WarningFn) |
420 | 309 | return; |
421 | 64 | |
422 | 64 | IRBuilder<> IRB(*C); |
423 | 64 | // Create the callback. |
424 | 64 | // FIXME: this function should have "Cold" calling conv, |
425 | 64 | // which is not yet implemented. |
426 | 0 | StringRef WarningFnName = Recover ? "__msan_warning" |
427 | 64 | : "__msan_warning_noreturn"; |
428 | 64 | WarningFn = M.getOrInsertFunction(WarningFnName, IRB.getVoidTy()); |
429 | 64 | |
430 | 320 | for (size_t AccessSizeIndex = 0; AccessSizeIndex < kNumberOfAccessSizes; |
431 | 256 | AccessSizeIndex++256 ) { |
432 | 256 | unsigned AccessSize = 1 << AccessSizeIndex; |
433 | 256 | std::string FunctionName = "__msan_maybe_warning_" + itostr(AccessSize); |
434 | 256 | MaybeWarningFn[AccessSizeIndex] = M.getOrInsertFunction( |
435 | 256 | FunctionName, IRB.getVoidTy(), IRB.getIntNTy(AccessSize * 8), |
436 | 256 | IRB.getInt32Ty()); |
437 | 256 | |
438 | 256 | FunctionName = "__msan_maybe_store_origin_" + itostr(AccessSize); |
439 | 256 | MaybeStoreOriginFn[AccessSizeIndex] = M.getOrInsertFunction( |
440 | 256 | FunctionName, IRB.getVoidTy(), IRB.getIntNTy(AccessSize * 8), |
441 | 256 | IRB.getInt8PtrTy(), IRB.getInt32Ty()); |
442 | 256 | } |
443 | 373 | |
444 | 373 | MsanSetAllocaOrigin4Fn = M.getOrInsertFunction( |
445 | 373 | "__msan_set_alloca_origin4", IRB.getVoidTy(), IRB.getInt8PtrTy(), IntptrTy, |
446 | 373 | IRB.getInt8PtrTy(), IntptrTy); |
447 | 373 | MsanPoisonStackFn = |
448 | 373 | M.getOrInsertFunction("__msan_poison_stack", IRB.getVoidTy(), |
449 | 373 | IRB.getInt8PtrTy(), IntptrTy); |
450 | 373 | MsanChainOriginFn = M.getOrInsertFunction( |
451 | 373 | "__msan_chain_origin", IRB.getInt32Ty(), IRB.getInt32Ty()); |
452 | 373 | MemmoveFn = M.getOrInsertFunction( |
453 | 373 | "__msan_memmove", IRB.getInt8PtrTy(), IRB.getInt8PtrTy(), |
454 | 373 | IRB.getInt8PtrTy(), IntptrTy); |
455 | 373 | MemcpyFn = M.getOrInsertFunction( |
456 | 373 | "__msan_memcpy", IRB.getInt8PtrTy(), IRB.getInt8PtrTy(), IRB.getInt8PtrTy(), |
457 | 373 | IntptrTy); |
458 | 373 | MemsetFn = M.getOrInsertFunction( |
459 | 373 | "__msan_memset", IRB.getInt8PtrTy(), IRB.getInt8PtrTy(), IRB.getInt32Ty(), |
460 | 373 | IntptrTy); |
461 | 373 | |
462 | 373 | // Create globals. |
463 | 373 | RetvalTLS = new GlobalVariable( |
464 | 373 | M, ArrayType::get(IRB.getInt64Ty(), kRetvalTLSSize / 8), false, |
465 | 373 | GlobalVariable::ExternalLinkage, nullptr, "__msan_retval_tls", nullptr, |
466 | 373 | GlobalVariable::InitialExecTLSModel); |
467 | 373 | RetvalOriginTLS = new GlobalVariable( |
468 | 373 | M, OriginTy, false, GlobalVariable::ExternalLinkage, nullptr, |
469 | 373 | "__msan_retval_origin_tls", nullptr, GlobalVariable::InitialExecTLSModel); |
470 | 373 | |
471 | 373 | ParamTLS = new GlobalVariable( |
472 | 373 | M, ArrayType::get(IRB.getInt64Ty(), kParamTLSSize / 8), false, |
473 | 373 | GlobalVariable::ExternalLinkage, nullptr, "__msan_param_tls", nullptr, |
474 | 373 | GlobalVariable::InitialExecTLSModel); |
475 | 373 | ParamOriginTLS = new GlobalVariable( |
476 | 373 | M, ArrayType::get(OriginTy, kParamTLSSize / 4), false, |
477 | 373 | GlobalVariable::ExternalLinkage, nullptr, "__msan_param_origin_tls", |
478 | 373 | nullptr, GlobalVariable::InitialExecTLSModel); |
479 | 373 | |
480 | 373 | VAArgTLS = new GlobalVariable( |
481 | 373 | M, ArrayType::get(IRB.getInt64Ty(), kParamTLSSize / 8), false, |
482 | 373 | GlobalVariable::ExternalLinkage, nullptr, "__msan_va_arg_tls", nullptr, |
483 | 373 | GlobalVariable::InitialExecTLSModel); |
484 | 373 | VAArgOverflowSizeTLS = new GlobalVariable( |
485 | 373 | M, IRB.getInt64Ty(), false, GlobalVariable::ExternalLinkage, nullptr, |
486 | 373 | "__msan_va_arg_overflow_size_tls", nullptr, |
487 | 373 | GlobalVariable::InitialExecTLSModel); |
488 | 373 | OriginTLS = new GlobalVariable( |
489 | 373 | M, IRB.getInt32Ty(), false, GlobalVariable::ExternalLinkage, nullptr, |
490 | 373 | "__msan_origin_tls", nullptr, GlobalVariable::InitialExecTLSModel); |
491 | 373 | |
492 | 373 | // We insert an empty inline asm after __msan_report* to avoid callback merge. |
493 | 373 | EmptyAsm = InlineAsm::get(FunctionType::get(IRB.getVoidTy(), false), |
494 | 373 | StringRef(""), StringRef(""), |
495 | 373 | /*hasSideEffects=*/true); |
496 | 373 | } |
497 | | |
498 | | /// \brief Module-level initialization. |
499 | | /// |
500 | | /// inserts a call to __msan_init to the module's constructor list. |
501 | 64 | bool MemorySanitizer::doInitialization(Module &M) { |
502 | 64 | auto &DL = M.getDataLayout(); |
503 | 64 | |
504 | 64 | Triple TargetTriple(M.getTargetTriple()); |
505 | 64 | switch (TargetTriple.getOS()) { |
506 | 0 | case Triple::FreeBSD: |
507 | 0 | switch (TargetTriple.getArch()) { |
508 | 0 | case Triple::x86_64: |
509 | 0 | MapParams = FreeBSD_X86_MemoryMapParams.bits64; |
510 | 0 | break; |
511 | 0 | case Triple::x86: |
512 | 0 | MapParams = FreeBSD_X86_MemoryMapParams.bits32; |
513 | 0 | break; |
514 | 0 | default: |
515 | 0 | report_fatal_error("unsupported architecture"); |
516 | 0 | } |
517 | 0 | break; |
518 | 64 | case Triple::Linux: |
519 | 64 | switch (TargetTriple.getArch()) { |
520 | 53 | case Triple::x86_64: |
521 | 53 | MapParams = Linux_X86_MemoryMapParams.bits64; |
522 | 53 | break; |
523 | 1 | case Triple::x86: |
524 | 1 | MapParams = Linux_X86_MemoryMapParams.bits32; |
525 | 1 | break; |
526 | 4 | case Triple::mips64: |
527 | 4 | case Triple::mips64el: |
528 | 4 | MapParams = Linux_MIPS_MemoryMapParams.bits64; |
529 | 4 | break; |
530 | 4 | case Triple::ppc64: |
531 | 4 | case Triple::ppc64le: |
532 | 4 | MapParams = Linux_PowerPC_MemoryMapParams.bits64; |
533 | 4 | break; |
534 | 2 | case Triple::aarch64: |
535 | 2 | case Triple::aarch64_be: |
536 | 2 | MapParams = Linux_ARM_MemoryMapParams.bits64; |
537 | 2 | break; |
538 | 0 | default: |
539 | 0 | report_fatal_error("unsupported architecture"); |
540 | 64 | } |
541 | 64 | break; |
542 | 0 | default: |
543 | 0 | report_fatal_error("unsupported operating system"); |
544 | 64 | } |
545 | 64 | |
546 | 64 | C = &(M.getContext()); |
547 | 64 | IRBuilder<> IRB(*C); |
548 | 64 | IntptrTy = IRB.getIntPtrTy(DL); |
549 | 64 | OriginTy = IRB.getInt32Ty(); |
550 | 64 | |
551 | 64 | ColdCallWeights = MDBuilder(*C).createBranchWeights(1, 1000); |
552 | 64 | OriginStoreWeights = MDBuilder(*C).createBranchWeights(1, 1000); |
553 | 64 | |
554 | 64 | std::tie(MsanCtorFunction, std::ignore) = |
555 | 64 | createSanitizerCtorAndInitFunctions(M, kMsanModuleCtorName, kMsanInitName, |
556 | 64 | /*InitArgTypes=*/{}, |
557 | 64 | /*InitArgs=*/{}); |
558 | 64 | if (ClWithComdat64 ) { |
559 | 1 | Comdat *MsanCtorComdat = M.getOrInsertComdat(kMsanModuleCtorName); |
560 | 1 | MsanCtorFunction->setComdat(MsanCtorComdat); |
561 | 1 | appendToGlobalCtors(M, MsanCtorFunction, 0, MsanCtorFunction); |
562 | 64 | } else { |
563 | 63 | appendToGlobalCtors(M, MsanCtorFunction, 0); |
564 | 63 | } |
565 | 64 | |
566 | 64 | |
567 | 64 | if (TrackOrigins) |
568 | 17 | new GlobalVariable(M, IRB.getInt32Ty(), true, GlobalValue::WeakODRLinkage, |
569 | 17 | IRB.getInt32(TrackOrigins), "__msan_track_origins"); |
570 | 64 | |
571 | 64 | if (Recover) |
572 | 0 | new GlobalVariable(M, IRB.getInt32Ty(), true, GlobalValue::WeakODRLinkage, |
573 | 0 | IRB.getInt32(Recover), "__msan_keep_going"); |
574 | 64 | |
575 | 64 | return true; |
576 | 64 | } |
577 | | |
578 | | namespace { |
579 | | |
580 | | /// \brief A helper class that handles instrumentation of VarArg |
581 | | /// functions on a particular platform. |
582 | | /// |
583 | | /// Implementations are expected to insert the instrumentation |
584 | | /// necessary to propagate argument shadow through VarArg function |
585 | | /// calls. Visit* methods are called during an InstVisitor pass over |
586 | | /// the function, and should avoid creating new basic blocks. A new |
587 | | /// instance of this class is created for each instrumented function. |
588 | | struct VarArgHelper { |
589 | | /// \brief Visit a CallSite. |
590 | | virtual void visitCallSite(CallSite &CS, IRBuilder<> &IRB) = 0; |
591 | | |
592 | | /// \brief Visit a va_start call. |
593 | | virtual void visitVAStartInst(VAStartInst &I) = 0; |
594 | | |
595 | | /// \brief Visit a va_copy call. |
596 | | virtual void visitVACopyInst(VACopyInst &I) = 0; |
597 | | |
598 | | /// \brief Finalize function instrumentation. |
599 | | /// |
600 | | /// This method is called after visiting all interesting (see above) |
601 | | /// instructions in a function. |
602 | | virtual void finalizeInstrumentation() = 0; |
603 | | |
604 | 373 | virtual ~VarArgHelper() {} |
605 | | }; |
606 | | |
607 | | struct MemorySanitizerVisitor; |
608 | | |
609 | | VarArgHelper* |
610 | | CreateVarArgHelper(Function &Func, MemorySanitizer &Msan, |
611 | | MemorySanitizerVisitor &Visitor); |
612 | | |
613 | 114 | unsigned TypeSizeToSizeIndex(unsigned TypeSize) { |
614 | 114 | if (TypeSize <= 8114 ) return 018 ; |
615 | 96 | return Log2_32_Ceil((TypeSize + 7) / 8); |
616 | 96 | } |
617 | | |
618 | | /// This class does all the work for a given function. Store and Load |
619 | | /// instructions store and load corresponding shadow and origin |
620 | | /// values. Most instructions propagate shadow from arguments to their |
621 | | /// return values. Certain instructions (most importantly, BranchInst) |
622 | | /// test their argument shadow and print reports (with a runtime call) if it's |
623 | | /// non-zero. |
624 | | struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> { |
625 | | Function &F; |
626 | | MemorySanitizer &MS; |
627 | | SmallVector<PHINode *, 16> ShadowPHINodes, OriginPHINodes; |
628 | | ValueMap<Value*, Value*> ShadowMap, OriginMap; |
629 | | std::unique_ptr<VarArgHelper> VAHelper; |
630 | | const TargetLibraryInfo *TLI; |
631 | | |
632 | | // The following flags disable parts of MSan instrumentation based on |
633 | | // blacklist contents and command-line options. |
634 | | bool InsertChecks; |
635 | | bool PropagateShadow; |
636 | | bool PoisonStack; |
637 | | bool PoisonUndef; |
638 | | bool CheckReturnValue; |
639 | | |
640 | | struct ShadowOriginAndInsertPoint { |
641 | | Value *Shadow; |
642 | | Value *Origin; |
643 | | Instruction *OrigIns; |
644 | | ShadowOriginAndInsertPoint(Value *S, Value *O, Instruction *I) |
645 | 91 | : Shadow(S), Origin(O), OrigIns(I) { } |
646 | | }; |
647 | | SmallVector<ShadowOriginAndInsertPoint, 16> InstrumentationList; |
648 | | SmallVector<StoreInst *, 16> StoreList; |
649 | | |
650 | | MemorySanitizerVisitor(Function &F, MemorySanitizer &MS) |
651 | 373 | : F(F), MS(MS), VAHelper(CreateVarArgHelper(F, MS, *this)) { |
652 | 373 | bool SanitizeFunction = F.hasFnAttribute(Attribute::SanitizeMemory); |
653 | 373 | InsertChecks = SanitizeFunction; |
654 | 373 | PropagateShadow = SanitizeFunction; |
655 | 327 | PoisonStack = SanitizeFunction && ClPoisonStack; |
656 | 327 | PoisonUndef = SanitizeFunction && ClPoisonUndef; |
657 | 373 | // FIXME: Consider using SpecialCaseList to specify a list of functions that |
658 | 373 | // must always return fully initialized values. For now, we hardcode "main". |
659 | 327 | CheckReturnValue = SanitizeFunction && (F.getName() == "main"); |
660 | 373 | TLI = &MS.getAnalysis<TargetLibraryInfoWrapperPass>().getTLI(); |
661 | 373 | |
662 | 373 | DEBUG(if (!InsertChecks) |
663 | 373 | dbgs() << "MemorySanitizer is not inserting checks into '" |
664 | 373 | << F.getName() << "'\n"); |
665 | 373 | } |
666 | | |
667 | 27 | Value *updateOrigin(Value *V, IRBuilder<> &IRB) { |
668 | 27 | if (MS.TrackOrigins <= 127 ) return V21 ; |
669 | 6 | return IRB.CreateCall(MS.MsanChainOriginFn, V); |
670 | 6 | } |
671 | | |
672 | 7 | Value *originToIntptr(IRBuilder<> &IRB, Value *Origin) { |
673 | 7 | const DataLayout &DL = F.getParent()->getDataLayout(); |
674 | 7 | unsigned IntptrSize = DL.getTypeStoreSize(MS.IntptrTy); |
675 | 7 | if (IntptrSize == kOriginSize7 ) return Origin0 ; |
676 | 7 | assert(IntptrSize == kOriginSize * 2); |
677 | 7 | Origin = IRB.CreateIntCast(Origin, MS.IntptrTy, /* isSigned */ false); |
678 | 7 | return IRB.CreateOr(Origin, IRB.CreateShl(Origin, kOriginSize * 8)); |
679 | 7 | } |
680 | | |
681 | | /// \brief Fill memory range with the given origin value. |
682 | | void paintOrigin(IRBuilder<> &IRB, Value *Origin, Value *OriginPtr, |
683 | 27 | unsigned Size, unsigned Alignment) { |
684 | 27 | const DataLayout &DL = F.getParent()->getDataLayout(); |
685 | 27 | unsigned IntptrAlignment = DL.getABITypeAlignment(MS.IntptrTy); |
686 | 27 | unsigned IntptrSize = DL.getTypeStoreSize(MS.IntptrTy); |
687 | 27 | assert(IntptrAlignment >= kMinOriginAlignment); |
688 | 27 | assert(IntptrSize >= kOriginSize); |
689 | 27 | |
690 | 27 | unsigned Ofs = 0; |
691 | 27 | unsigned CurrentAlignment = Alignment; |
692 | 27 | if (Alignment >= IntptrAlignment && 27 IntptrSize > kOriginSize7 ) { |
693 | 7 | Value *IntptrOrigin = originToIntptr(IRB, Origin); |
694 | 7 | Value *IntptrOriginPtr = |
695 | 7 | IRB.CreatePointerCast(OriginPtr, PointerType::get(MS.IntptrTy, 0)); |
696 | 14 | for (unsigned i = 0; i < Size / IntptrSize14 ; ++i7 ) { |
697 | 3 | Value *Ptr = i ? IRB.CreateConstGEP1_32(MS.IntptrTy, IntptrOriginPtr, i) |
698 | 4 | : IntptrOriginPtr; |
699 | 7 | IRB.CreateAlignedStore(IntptrOrigin, Ptr, CurrentAlignment); |
700 | 7 | Ofs += IntptrSize / kOriginSize; |
701 | 7 | CurrentAlignment = IntptrAlignment; |
702 | 7 | } |
703 | 7 | } |
704 | 27 | |
705 | 57 | for (unsigned i = Ofs; i < (Size + kOriginSize - 1) / kOriginSize57 ; ++i30 ) { |
706 | 30 | Value *GEP = |
707 | 30 | i ? IRB.CreateConstGEP1_32(nullptr, OriginPtr, i)7 : OriginPtr23 ; |
708 | 30 | IRB.CreateAlignedStore(Origin, GEP, CurrentAlignment); |
709 | 30 | CurrentAlignment = kMinOriginAlignment; |
710 | 30 | } |
711 | 27 | } |
712 | | |
713 | | void storeOrigin(IRBuilder<> &IRB, Value *Addr, Value *Shadow, Value *Origin, |
714 | 30 | unsigned Alignment, bool AsCall) { |
715 | 30 | const DataLayout &DL = F.getParent()->getDataLayout(); |
716 | 30 | unsigned OriginAlignment = std::max(kMinOriginAlignment, Alignment); |
717 | 30 | unsigned StoreSize = DL.getTypeStoreSize(Shadow->getType()); |
718 | 30 | if (Shadow->getType()->isAggregateType()30 ) { |
719 | 4 | paintOrigin(IRB, updateOrigin(Origin, IRB), |
720 | 4 | getOriginPtr(Addr, IRB, Alignment), StoreSize, |
721 | 4 | OriginAlignment); |
722 | 30 | } else { |
723 | 26 | Value *ConvertedShadow = convertToShadowTyNoVec(Shadow, IRB); |
724 | 26 | Constant *ConstantShadow = dyn_cast_or_null<Constant>(ConvertedShadow); |
725 | 26 | if (ConstantShadow26 ) { |
726 | 2 | if (ClCheckConstantShadow && 2 !ConstantShadow->isZeroValue()2 ) |
727 | 1 | paintOrigin(IRB, updateOrigin(Origin, IRB), |
728 | 1 | getOriginPtr(Addr, IRB, Alignment), StoreSize, |
729 | 1 | OriginAlignment); |
730 | 2 | return; |
731 | 2 | } |
732 | 24 | |
733 | 24 | unsigned TypeSizeInBits = |
734 | 24 | DL.getTypeSizeInBits(ConvertedShadow->getType()); |
735 | 24 | unsigned SizeIndex = TypeSizeToSizeIndex(TypeSizeInBits); |
736 | 24 | if (AsCall && 24 SizeIndex < kNumberOfAccessSizes2 ) { |
737 | 2 | Value *Fn = MS.MaybeStoreOriginFn[SizeIndex]; |
738 | 2 | Value *ConvertedShadow2 = IRB.CreateZExt( |
739 | 2 | ConvertedShadow, IRB.getIntNTy(8 * (1 << SizeIndex))); |
740 | 2 | IRB.CreateCall(Fn, {ConvertedShadow2, |
741 | 2 | IRB.CreatePointerCast(Addr, IRB.getInt8PtrTy()), |
742 | 2 | Origin}); |
743 | 24 | } else { |
744 | 22 | Value *Cmp = IRB.CreateICmpNE( |
745 | 22 | ConvertedShadow, getCleanShadow(ConvertedShadow), "_mscmp"); |
746 | 22 | Instruction *CheckTerm = SplitBlockAndInsertIfThen( |
747 | 22 | Cmp, &*IRB.GetInsertPoint(), false, MS.OriginStoreWeights); |
748 | 22 | IRBuilder<> IRBNew(CheckTerm); |
749 | 22 | paintOrigin(IRBNew, updateOrigin(Origin, IRBNew), |
750 | 22 | getOriginPtr(Addr, IRBNew, Alignment), StoreSize, |
751 | 22 | OriginAlignment); |
752 | 22 | } |
753 | 26 | } |
754 | 30 | } |
755 | | |
756 | 373 | void materializeStores(bool InstrumentWithCalls) { |
757 | 126 | for (StoreInst *SI : StoreList) { |
758 | 126 | IRBuilder<> IRB(SI); |
759 | 126 | Value *Val = SI->getValueOperand(); |
760 | 126 | Value *Addr = SI->getPointerOperand(); |
761 | 126 | Value *Shadow = SI->isAtomic() ? getCleanShadow(Val)12 : getShadow(Val)114 ; |
762 | 126 | Value *ShadowPtr = getShadowPtr(Addr, Shadow->getType(), IRB); |
763 | 126 | |
764 | 126 | StoreInst *NewSI = |
765 | 126 | IRB.CreateAlignedStore(Shadow, ShadowPtr, SI->getAlignment()); |
766 | 126 | DEBUG(dbgs() << " STORE: " << *NewSI << "\n"); |
767 | 126 | (void)NewSI; |
768 | 126 | |
769 | 126 | if (ClCheckAccessAddress) |
770 | 73 | insertShadowCheck(Addr, SI); |
771 | 126 | |
772 | 126 | if (SI->isAtomic()) |
773 | 12 | SI->setOrdering(addReleaseOrdering(SI->getOrdering())); |
774 | 126 | |
775 | 126 | if (MS.TrackOrigins && 126 !SI->isAtomic()38 ) |
776 | 30 | storeOrigin(IRB, Addr, Shadow, getOrigin(Val), SI->getAlignment(), |
777 | 30 | InstrumentWithCalls); |
778 | 126 | } |
779 | 373 | } |
780 | | |
781 | | void materializeOneCheck(Instruction *OrigIns, Value *Shadow, Value *Origin, |
782 | 91 | bool AsCall) { |
783 | 91 | IRBuilder<> IRB(OrigIns); |
784 | 91 | DEBUG(dbgs() << " SHAD0 : " << *Shadow << "\n"); |
785 | 91 | Value *ConvertedShadow = convertToShadowTyNoVec(Shadow, IRB); |
786 | 91 | DEBUG(dbgs() << " SHAD1 : " << *ConvertedShadow << "\n"); |
787 | 91 | |
788 | 91 | Constant *ConstantShadow = dyn_cast_or_null<Constant>(ConvertedShadow); |
789 | 91 | if (ConstantShadow91 ) { |
790 | 1 | if (ClCheckConstantShadow && 1 !ConstantShadow->isZeroValue()1 ) { |
791 | 1 | if (MS.TrackOrigins1 ) { |
792 | 1 | IRB.CreateStore(Origin ? (Value *)Origin1 : (Value *)IRB.getInt32(0)0 , |
793 | 1 | MS.OriginTLS); |
794 | 1 | } |
795 | 1 | IRB.CreateCall(MS.WarningFn, {}); |
796 | 1 | IRB.CreateCall(MS.EmptyAsm, {}); |
797 | 1 | // FIXME: Insert UnreachableInst if !MS.Recover? |
798 | 1 | // This may invalidate some of the following checks and needs to be done |
799 | 1 | // at the very end. |
800 | 1 | } |
801 | 1 | return; |
802 | 1 | } |
803 | 90 | |
804 | 90 | const DataLayout &DL = OrigIns->getModule()->getDataLayout(); |
805 | 90 | |
806 | 90 | unsigned TypeSizeInBits = DL.getTypeSizeInBits(ConvertedShadow->getType()); |
807 | 90 | unsigned SizeIndex = TypeSizeToSizeIndex(TypeSizeInBits); |
808 | 90 | if (AsCall && 90 SizeIndex < kNumberOfAccessSizes12 ) { |
809 | 11 | Value *Fn = MS.MaybeWarningFn[SizeIndex]; |
810 | 11 | Value *ConvertedShadow2 = |
811 | 11 | IRB.CreateZExt(ConvertedShadow, IRB.getIntNTy(8 * (1 << SizeIndex))); |
812 | 2 | IRB.CreateCall(Fn, {ConvertedShadow2, MS.TrackOrigins && Origin |
813 | 2 | ? Origin |
814 | 9 | : (Value *)IRB.getInt32(0)}); |
815 | 90 | } else { |
816 | 79 | Value *Cmp = IRB.CreateICmpNE(ConvertedShadow, |
817 | 79 | getCleanShadow(ConvertedShadow), "_mscmp"); |
818 | 79 | Instruction *CheckTerm = SplitBlockAndInsertIfThen( |
819 | 79 | Cmp, OrigIns, |
820 | 79 | /* Unreachable */ !MS.Recover, MS.ColdCallWeights); |
821 | 79 | |
822 | 79 | IRB.SetInsertPoint(CheckTerm); |
823 | 79 | if (MS.TrackOrigins79 ) { |
824 | 9 | IRB.CreateStore(Origin ? (Value *)Origin9 : (Value *)IRB.getInt32(0)0 , |
825 | 9 | MS.OriginTLS); |
826 | 9 | } |
827 | 79 | IRB.CreateCall(MS.WarningFn, {}); |
828 | 79 | IRB.CreateCall(MS.EmptyAsm, {}); |
829 | 79 | DEBUG(dbgs() << " CHECK: " << *Cmp << "\n"); |
830 | 79 | } |
831 | 91 | } |
832 | | |
833 | 373 | void materializeChecks(bool InstrumentWithCalls) { |
834 | 91 | for (const auto &ShadowData : InstrumentationList) { |
835 | 91 | Instruction *OrigIns = ShadowData.OrigIns; |
836 | 91 | Value *Shadow = ShadowData.Shadow; |
837 | 91 | Value *Origin = ShadowData.Origin; |
838 | 91 | materializeOneCheck(OrigIns, Shadow, Origin, InstrumentWithCalls); |
839 | 91 | } |
840 | 373 | DEBUG(dbgs() << "DONE:\n" << F); |
841 | 373 | } |
842 | | |
843 | | /// \brief Add MemorySanitizer instrumentation to a function. |
844 | 373 | bool runOnFunction() { |
845 | 373 | MS.initializeCallbacks(*F.getParent()); |
846 | 373 | |
847 | 373 | // In the presence of unreachable blocks, we may see Phi nodes with |
848 | 373 | // incoming nodes from such blocks. Since InstVisitor skips unreachable |
849 | 373 | // blocks, such nodes will not have any shadow value associated with them. |
850 | 373 | // It's easier to remove unreachable blocks than deal with missing shadow. |
851 | 373 | removeUnreachableBlocks(F); |
852 | 373 | |
853 | 373 | // Iterate all BBs in depth-first order and create shadow instructions |
854 | 373 | // for all instructions (where applicable). |
855 | 373 | // For PHI nodes we create dummy shadow PHIs which will be finalized later. |
856 | 373 | for (BasicBlock *BB : depth_first(&F.getEntryBlock())) |
857 | 404 | visit(*BB); |
858 | 373 | |
859 | 373 | |
860 | 373 | // Finalize PHI nodes. |
861 | 2 | for (PHINode *PN : ShadowPHINodes) { |
862 | 2 | PHINode *PNS = cast<PHINode>(getShadow(PN)); |
863 | 2 | PHINode *PNO = MS.TrackOrigins ? cast<PHINode>(getOrigin(PN))1 : nullptr1 ; |
864 | 2 | size_t NumValues = PN->getNumIncomingValues(); |
865 | 6 | for (size_t v = 0; v < NumValues6 ; v++4 ) { |
866 | 4 | PNS->addIncoming(getShadow(PN, v), PN->getIncomingBlock(v)); |
867 | 4 | if (PNO4 ) PNO->addIncoming(getOrigin(PN, v), PN->getIncomingBlock(v))2 ; |
868 | 4 | } |
869 | 2 | } |
870 | 373 | |
871 | 373 | VAHelper->finalizeInstrumentation(); |
872 | 373 | |
873 | 373 | bool InstrumentWithCalls = ClInstrumentationWithCallThreshold >= 0 && |
874 | 373 | InstrumentationList.size() + StoreList.size() > |
875 | 373 | (unsigned)ClInstrumentationWithCallThreshold; |
876 | 373 | |
877 | 373 | // Delayed instrumentation of StoreInst. |
878 | 373 | // This may add new checks to be inserted later. |
879 | 373 | materializeStores(InstrumentWithCalls); |
880 | 373 | |
881 | 373 | // Insert shadow value checks. |
882 | 373 | materializeChecks(InstrumentWithCalls); |
883 | 373 | |
884 | 373 | return true; |
885 | 373 | } |
886 | | |
887 | | /// \brief Compute the shadow type that corresponds to a given Value. |
888 | 1.14k | Type *getShadowTy(Value *V) { |
889 | 1.14k | return getShadowTy(V->getType()); |
890 | 1.14k | } |
891 | | |
892 | | /// \brief Compute the shadow type that corresponds to a given Type. |
893 | 2.25k | Type *getShadowTy(Type *OrigTy) { |
894 | 2.25k | if (!OrigTy->isSized()2.25k ) { |
895 | 89 | return nullptr; |
896 | 89 | } |
897 | 2.17k | // For integer type, shadow is the same as the original type. |
898 | 2.17k | // This may return weird-sized types like i1. |
899 | 2.17k | if (IntegerType *2.17k IT2.17k = dyn_cast<IntegerType>(OrigTy)) |
900 | 1.15k | return IT; |
901 | 1.01k | const DataLayout &DL = F.getParent()->getDataLayout(); |
902 | 1.01k | if (VectorType *VT1.01k = dyn_cast<VectorType>(OrigTy)) { |
903 | 187 | uint32_t EltSize = DL.getTypeSizeInBits(VT->getElementType()); |
904 | 187 | return VectorType::get(IntegerType::get(*MS.C, EltSize), |
905 | 187 | VT->getNumElements()); |
906 | 187 | } |
907 | 829 | if (ArrayType *829 AT829 = dyn_cast<ArrayType>(OrigTy)) { |
908 | 39 | return ArrayType::get(getShadowTy(AT->getElementType()), |
909 | 39 | AT->getNumElements()); |
910 | 39 | } |
911 | 790 | if (StructType *790 ST790 = dyn_cast<StructType>(OrigTy)) { |
912 | 42 | SmallVector<Type*, 4> Elements; |
913 | 135 | for (unsigned i = 0, n = ST->getNumElements(); i < n135 ; i++93 ) |
914 | 93 | Elements.push_back(getShadowTy(ST->getElementType(i))); |
915 | 42 | StructType *Res = StructType::get(*MS.C, Elements, ST->isPacked()); |
916 | 42 | DEBUG(dbgs() << "getShadowTy: " << *ST << " ===> " << *Res << "\n"); |
917 | 42 | return Res; |
918 | 42 | } |
919 | 748 | uint32_t TypeSize = DL.getTypeSizeInBits(OrigTy); |
920 | 748 | return IntegerType::get(*MS.C, TypeSize); |
921 | 748 | } |
922 | | |
923 | | /// \brief Flatten a vector type. |
924 | 129 | Type *getShadowTyNoVec(Type *ty) { |
925 | 129 | if (VectorType *vt = dyn_cast<VectorType>(ty)) |
926 | 4 | return IntegerType::get(*MS.C, vt->getBitWidth()); |
927 | 125 | return ty; |
928 | 125 | } |
929 | | |
930 | | /// \brief Convert a shadow value to it's flattened variant. |
931 | 128 | Value *convertToShadowTyNoVec(Value *V, IRBuilder<> &IRB) { |
932 | 128 | Type *Ty = V->getType(); |
933 | 128 | Type *NoVecTy = getShadowTyNoVec(Ty); |
934 | 128 | if (Ty == NoVecTy128 ) return V125 ; |
935 | 3 | return IRB.CreateBitCast(V, NoVecTy); |
936 | 3 | } |
937 | | |
938 | | /// \brief Compute the integer shadow offset that corresponds to a given |
939 | | /// application address. |
940 | | /// |
941 | | /// Offset = (Addr & ~AndMask) ^ XorMask |
942 | 405 | Value *getShadowPtrOffset(Value *Addr, IRBuilder<> &IRB) { |
943 | 405 | Value *OffsetLong = IRB.CreatePointerCast(Addr, MS.IntptrTy); |
944 | 405 | |
945 | 405 | uint64_t AndMask = MS.MapParams->AndMask; |
946 | 405 | if (AndMask) |
947 | 23 | OffsetLong = |
948 | 23 | IRB.CreateAnd(OffsetLong, ConstantInt::get(MS.IntptrTy, ~AndMask)); |
949 | 405 | |
950 | 405 | uint64_t XorMask = MS.MapParams->XorMask; |
951 | 405 | if (XorMask) |
952 | 404 | OffsetLong = |
953 | 404 | IRB.CreateXor(OffsetLong, ConstantInt::get(MS.IntptrTy, XorMask)); |
954 | 405 | return OffsetLong; |
955 | 405 | } |
956 | | |
957 | | /// \brief Compute the shadow address that corresponds to a given application |
958 | | /// address. |
959 | | /// |
960 | | /// Shadow = ShadowBase + Offset |
961 | | Value *getShadowPtr(Value *Addr, Type *ShadowTy, |
962 | 356 | IRBuilder<> &IRB) { |
963 | 356 | Value *ShadowLong = getShadowPtrOffset(Addr, IRB); |
964 | 356 | uint64_t ShadowBase = MS.MapParams->ShadowBase; |
965 | 356 | if (ShadowBase != 0) |
966 | 22 | ShadowLong = |
967 | 22 | IRB.CreateAdd(ShadowLong, |
968 | 22 | ConstantInt::get(MS.IntptrTy, ShadowBase)); |
969 | 356 | return IRB.CreateIntToPtr(ShadowLong, PointerType::get(ShadowTy, 0)); |
970 | 356 | } |
971 | | |
972 | | /// \brief Compute the origin address that corresponds to a given application |
973 | | /// address. |
974 | | /// |
975 | | /// OriginAddr = (OriginBase + Offset) & ~3ULL |
976 | 49 | Value *getOriginPtr(Value *Addr, IRBuilder<> &IRB, unsigned Alignment) { |
977 | 49 | Value *OriginLong = getShadowPtrOffset(Addr, IRB); |
978 | 49 | uint64_t OriginBase = MS.MapParams->OriginBase; |
979 | 49 | if (OriginBase != 0) |
980 | 49 | OriginLong = |
981 | 49 | IRB.CreateAdd(OriginLong, |
982 | 49 | ConstantInt::get(MS.IntptrTy, OriginBase)); |
983 | 49 | if (Alignment < kMinOriginAlignment49 ) { |
984 | 9 | uint64_t Mask = kMinOriginAlignment - 1; |
985 | 9 | OriginLong = IRB.CreateAnd(OriginLong, |
986 | 9 | ConstantInt::get(MS.IntptrTy, ~Mask)); |
987 | 9 | } |
988 | 49 | return IRB.CreateIntToPtr(OriginLong, |
989 | 49 | PointerType::get(IRB.getInt32Ty(), 0)); |
990 | 49 | } |
991 | | |
992 | | /// \brief Compute the shadow address for a given function argument. |
993 | | /// |
994 | | /// Shadow = ParamTLS+ArgOffset. |
995 | | Value *getShadowPtrForArgument(Value *A, IRBuilder<> &IRB, |
996 | 504 | int ArgOffset) { |
997 | 504 | Value *Base = IRB.CreatePointerCast(MS.ParamTLS, MS.IntptrTy); |
998 | 504 | Base = IRB.CreateAdd(Base, ConstantInt::get(MS.IntptrTy, ArgOffset)); |
999 | 504 | return IRB.CreateIntToPtr(Base, PointerType::get(getShadowTy(A), 0), |
1000 | 504 | "_msarg"); |
1001 | 504 | } |
1002 | | |
1003 | | /// \brief Compute the origin address for a given function argument. |
1004 | | Value *getOriginPtrForArgument(Value *A, IRBuilder<> &IRB, |
1005 | 97 | int ArgOffset) { |
1006 | 97 | if (!MS.TrackOrigins97 ) return nullptr0 ; |
1007 | 97 | Value *Base = IRB.CreatePointerCast(MS.ParamOriginTLS, MS.IntptrTy); |
1008 | 97 | Base = IRB.CreateAdd(Base, ConstantInt::get(MS.IntptrTy, ArgOffset)); |
1009 | 97 | return IRB.CreateIntToPtr(Base, PointerType::get(MS.OriginTy, 0), |
1010 | 97 | "_msarg_o"); |
1011 | 97 | } |
1012 | | |
1013 | | /// \brief Compute the shadow address for a retval. |
1014 | 283 | Value *getShadowPtrForRetval(Value *A, IRBuilder<> &IRB) { |
1015 | 283 | Value *Base = IRB.CreatePointerCast(MS.RetvalTLS, MS.IntptrTy); |
1016 | 283 | return IRB.CreateIntToPtr(Base, PointerType::get(getShadowTy(A), 0), |
1017 | 283 | "_msret"); |
1018 | 283 | } |
1019 | | |
1020 | | /// \brief Compute the origin address for a retval. |
1021 | 65 | Value *getOriginPtrForRetval(IRBuilder<> &IRB) { |
1022 | 65 | // We keep a single origin for the entire retval. Might be too optimistic. |
1023 | 65 | return MS.RetvalOriginTLS; |
1024 | 65 | } |
1025 | | |
1026 | | /// \brief Set SV to be the shadow value for V. |
1027 | 626 | void setShadow(Value *V, Value *SV) { |
1028 | 626 | assert(!ShadowMap.count(V) && "Values may only have one shadow"); |
1029 | 626 | ShadowMap[V] = PropagateShadow ? SV543 : getCleanShadow(V)83 ; |
1030 | 626 | } |
1031 | | |
1032 | | /// \brief Set Origin to be the origin value for V. |
1033 | 679 | void setOrigin(Value *V, Value *Origin) { |
1034 | 679 | if (!MS.TrackOrigins679 ) return459 ; |
1035 | 679 | assert(!OriginMap.count(V) && "Values may only have one origin"); |
1036 | 220 | DEBUG(dbgs() << "ORIGIN: " << *V << " ==> " << *Origin << "\n"); |
1037 | 679 | OriginMap[V] = Origin; |
1038 | 679 | } |
1039 | | |
1040 | 930 | Constant *getCleanShadow(Type *OrigTy) { |
1041 | 930 | Type *ShadowTy = getShadowTy(OrigTy); |
1042 | 930 | if (!ShadowTy) |
1043 | 89 | return nullptr; |
1044 | 841 | return Constant::getNullValue(ShadowTy); |
1045 | 841 | } |
1046 | | |
1047 | | /// \brief Create a clean shadow value for a given value. |
1048 | | /// |
1049 | | /// Clean shadow (all zeroes) means all bits of the value are defined |
1050 | | /// (initialized). |
1051 | 928 | Constant *getCleanShadow(Value *V) { |
1052 | 928 | return getCleanShadow(V->getType()); |
1053 | 928 | } |
1054 | | |
1055 | | /// \brief Create a dirty shadow of a given shadow type. |
1056 | 40 | Constant *getPoisonedShadow(Type *ShadowTy) { |
1057 | 40 | assert(ShadowTy); |
1058 | 40 | if (isa<IntegerType>(ShadowTy) || 40 isa<VectorType>(ShadowTy)16 ) |
1059 | 27 | return Constant::getAllOnesValue(ShadowTy); |
1060 | 13 | if (ArrayType *13 AT13 = dyn_cast<ArrayType>(ShadowTy)) { |
1061 | 6 | SmallVector<Constant *, 4> Vals(AT->getNumElements(), |
1062 | 6 | getPoisonedShadow(AT->getElementType())); |
1063 | 6 | return ConstantArray::get(AT, Vals); |
1064 | 6 | } |
1065 | 7 | if (StructType *7 ST7 = dyn_cast<StructType>(ShadowTy)) { |
1066 | 7 | SmallVector<Constant *, 4> Vals; |
1067 | 21 | for (unsigned i = 0, n = ST->getNumElements(); i < n21 ; i++14 ) |
1068 | 14 | Vals.push_back(getPoisonedShadow(ST->getElementType(i))); |
1069 | 7 | return ConstantStruct::get(ST, Vals); |
1070 | 7 | } |
1071 | 0 | llvm_unreachable0 ("Unexpected shadow type"); |
1072 | 0 | } |
1073 | | |
1074 | | /// \brief Create a dirty shadow for a given value. |
1075 | 16 | Constant *getPoisonedShadow(Value *V) { |
1076 | 16 | Type *ShadowTy = getShadowTy(V); |
1077 | 16 | if (!ShadowTy) |
1078 | 0 | return nullptr; |
1079 | 16 | return getPoisonedShadow(ShadowTy); |
1080 | 16 | } |
1081 | | |
1082 | | /// \brief Create a clean (zero) origin. |
1083 | 410 | Value *getCleanOrigin() { |
1084 | 410 | return Constant::getNullValue(MS.OriginTy); |
1085 | 410 | } |
1086 | | |
1087 | | /// \brief Get the shadow value for a given Value. |
1088 | | /// |
1089 | | /// This function either returns the value set earlier with setShadow, |
1090 | | /// or extracts if from ParamTLS (for function arguments). |
1091 | 1.38k | Value *getShadow(Value *V) { |
1092 | 1.38k | if (!PropagateShadow1.38k ) return getCleanShadow(V)240 ; |
1093 | 1.14k | if (Instruction *1.14k I1.14k = dyn_cast<Instruction>(V)) { |
1094 | 528 | // For instructions the shadow is already stored in the map. |
1095 | 528 | Value *Shadow = ShadowMap[V]; |
1096 | 528 | if (!Shadow528 ) { |
1097 | 0 | DEBUG(dbgs() << "No shadow: " << *V << "\n" << *(I->getParent())); |
1098 | 0 | (void)I; |
1099 | 0 | assert(Shadow && "No shadow for a value"); |
1100 | 0 | } |
1101 | 528 | return Shadow; |
1102 | 528 | } |
1103 | 619 | if (UndefValue *619 U619 = dyn_cast<UndefValue>(V)) { |
1104 | 16 | Value *AllOnes = PoisonUndef ? getPoisonedShadow(V)16 : getCleanShadow(V)0 ; |
1105 | 16 | DEBUG(dbgs() << "Undef: " << *U << " ==> " << *AllOnes << "\n"); |
1106 | 16 | (void)U; |
1107 | 16 | return AllOnes; |
1108 | 16 | } |
1109 | 603 | if (Argument *603 A603 = dyn_cast<Argument>(V)) { |
1110 | 378 | // For arguments we compute the shadow on demand and store it in the map. |
1111 | 378 | Value **ShadowPtr = &ShadowMap[V]; |
1112 | 378 | if (*ShadowPtr) |
1113 | 66 | return *ShadowPtr; |
1114 | 312 | Function *F = A->getParent(); |
1115 | 312 | IRBuilder<> EntryIRB(F->getEntryBlock().getFirstNonPHI()); |
1116 | 312 | unsigned ArgOffset = 0; |
1117 | 312 | const DataLayout &DL = F->getParent()->getDataLayout(); |
1118 | 561 | for (auto &FArg : F->args()) { |
1119 | 561 | if (!FArg.getType()->isSized()561 ) { |
1120 | 0 | DEBUG(dbgs() << "Arg is not sized\n"); |
1121 | 0 | continue; |
1122 | 0 | } |
1123 | 561 | unsigned Size = |
1124 | 561 | FArg.hasByValAttr() |
1125 | 2 | ? DL.getTypeAllocSize(FArg.getType()->getPointerElementType()) |
1126 | 559 | : DL.getTypeAllocSize(FArg.getType()); |
1127 | 561 | if (A == &FArg561 ) { |
1128 | 312 | bool Overflow = ArgOffset + Size > kParamTLSSize; |
1129 | 312 | Value *Base = getShadowPtrForArgument(&FArg, EntryIRB, ArgOffset); |
1130 | 312 | if (FArg.hasByValAttr()312 ) { |
1131 | 2 | // ByVal pointer itself has clean shadow. We copy the actual |
1132 | 2 | // argument shadow to the underlying memory. |
1133 | 2 | // Figure out maximal valid memcpy alignment. |
1134 | 2 | unsigned ArgAlign = FArg.getParamAlignment(); |
1135 | 2 | if (ArgAlign == 02 ) { |
1136 | 2 | Type *EltType = A->getType()->getPointerElementType(); |
1137 | 2 | ArgAlign = DL.getABITypeAlignment(EltType); |
1138 | 2 | } |
1139 | 2 | if (Overflow2 ) { |
1140 | 0 | // ParamTLS overflow. |
1141 | 0 | EntryIRB.CreateMemSet( |
1142 | 0 | getShadowPtr(V, EntryIRB.getInt8Ty(), EntryIRB), |
1143 | 0 | Constant::getNullValue(EntryIRB.getInt8Ty()), Size, ArgAlign); |
1144 | 2 | } else { |
1145 | 2 | unsigned CopyAlign = std::min(ArgAlign, kShadowTLSAlignment); |
1146 | 2 | Value *Cpy = EntryIRB.CreateMemCpy( |
1147 | 2 | getShadowPtr(V, EntryIRB.getInt8Ty(), EntryIRB), Base, Size, |
1148 | 2 | CopyAlign); |
1149 | 2 | DEBUG(dbgs() << " ByValCpy: " << *Cpy << "\n"); |
1150 | 2 | (void)Cpy; |
1151 | 2 | } |
1152 | 2 | *ShadowPtr = getCleanShadow(V); |
1153 | 312 | } else { |
1154 | 310 | if (Overflow310 ) { |
1155 | 0 | // ParamTLS overflow. |
1156 | 0 | *ShadowPtr = getCleanShadow(V); |
1157 | 310 | } else { |
1158 | 310 | *ShadowPtr = |
1159 | 310 | EntryIRB.CreateAlignedLoad(Base, kShadowTLSAlignment); |
1160 | 310 | } |
1161 | 310 | } |
1162 | 312 | DEBUG(dbgs() << " ARG: " << FArg << " ==> " << |
1163 | 312 | **ShadowPtr << "\n"); |
1164 | 312 | if (MS.TrackOrigins && 312 !Overflow88 ) { |
1165 | 88 | Value *OriginPtr = |
1166 | 88 | getOriginPtrForArgument(&FArg, EntryIRB, ArgOffset); |
1167 | 88 | setOrigin(A, EntryIRB.CreateLoad(OriginPtr)); |
1168 | 312 | } else { |
1169 | 224 | setOrigin(A, getCleanOrigin()); |
1170 | 224 | } |
1171 | 312 | } |
1172 | 561 | ArgOffset += alignTo(Size, kShadowTLSAlignment); |
1173 | 561 | } |
1174 | 378 | assert(*ShadowPtr && "Could not find shadow for an argument"); |
1175 | 378 | return *ShadowPtr; |
1176 | 378 | } |
1177 | 225 | // For everything else the shadow is zero. |
1178 | 225 | return getCleanShadow(V); |
1179 | 225 | } |
1180 | | |
1181 | | /// \brief Get the shadow for i-th argument of the instruction I. |
1182 | 201 | Value *getShadow(Instruction *I, int i) { |
1183 | 201 | return getShadow(I->getOperand(i)); |
1184 | 201 | } |
1185 | | |
1186 | | /// \brief Get the origin for a value. |
1187 | 415 | Value *getOrigin(Value *V) { |
1188 | 415 | if (!MS.TrackOrigins415 ) return nullptr206 ; |
1189 | 209 | if (209 !PropagateShadow209 ) return getCleanOrigin()9 ; |
1190 | 200 | if (200 isa<Constant>(V)200 ) return getCleanOrigin()22 ; |
1191 | 200 | assert((isa<Instruction>(V) || isa<Argument>(V)) && |
1192 | 178 | "Unexpected value type in getOrigin()"); |
1193 | 178 | Value *Origin = OriginMap[V]; |
1194 | 178 | assert(Origin && "Missing origin"); |
1195 | 178 | return Origin; |
1196 | 178 | } |
1197 | | |
1198 | | /// \brief Get the origin for i-th argument of the instruction I. |
1199 | 121 | Value *getOrigin(Instruction *I, int i) { |
1200 | 121 | return getOrigin(I->getOperand(i)); |
1201 | 121 | } |
1202 | | |
1203 | | /// \brief Remember the place where a shadow check should be inserted. |
1204 | | /// |
1205 | | /// This location will be later instrumented with a check that will print a |
1206 | | /// UMR warning in runtime if the shadow value is not 0. |
1207 | 91 | void insertShadowCheck(Value *Shadow, Value *Origin, Instruction *OrigIns) { |
1208 | 91 | assert(Shadow); |
1209 | 91 | if (!InsertChecks91 ) return0 ; |
1210 | | #ifndef NDEBUG |
1211 | | Type *ShadowTy = Shadow->getType(); |
1212 | | assert((isa<IntegerType>(ShadowTy) || isa<VectorType>(ShadowTy)) && |
1213 | | "Can only insert checks for integer and vector shadow types"); |
1214 | | #endif |
1215 | 0 | InstrumentationList.push_back( |
1216 | 91 | ShadowOriginAndInsertPoint(Shadow, Origin, OrigIns)); |
1217 | 91 | } |
1218 | | |
1219 | | /// \brief Remember the place where a shadow check should be inserted. |
1220 | | /// |
1221 | | /// This location will be later instrumented with a check that will print a |
1222 | | /// UMR warning in runtime if the value is not fully defined. |
1223 | 263 | void insertShadowCheck(Value *Val, Instruction *OrigIns) { |
1224 | 263 | assert(Val); |
1225 | 263 | Value *Shadow, *Origin; |
1226 | 263 | if (ClCheckConstantShadow263 ) { |
1227 | 1 | Shadow = getShadow(Val); |
1228 | 1 | if (!Shadow1 ) return0 ; |
1229 | 1 | Origin = getOrigin(Val); |
1230 | 263 | } else { |
1231 | 262 | Shadow = dyn_cast_or_null<Instruction>(getShadow(Val)); |
1232 | 262 | if (!Shadow262 ) return177 ; |
1233 | 85 | Origin = dyn_cast_or_null<Instruction>(getOrigin(Val)); |
1234 | 85 | } |
1235 | 86 | insertShadowCheck(Shadow, Origin, OrigIns); |
1236 | 86 | } |
1237 | | |
1238 | 24 | AtomicOrdering addReleaseOrdering(AtomicOrdering a) { |
1239 | 24 | switch (a) { |
1240 | 0 | case AtomicOrdering::NotAtomic: |
1241 | 0 | return AtomicOrdering::NotAtomic; |
1242 | 12 | case AtomicOrdering::Unordered: |
1243 | 12 | case AtomicOrdering::Monotonic: |
1244 | 12 | case AtomicOrdering::Release: |
1245 | 12 | return AtomicOrdering::Release; |
1246 | 0 | case AtomicOrdering::Acquire: |
1247 | 0 | case AtomicOrdering::AcquireRelease: |
1248 | 0 | return AtomicOrdering::AcquireRelease; |
1249 | 12 | case AtomicOrdering::SequentiallyConsistent: |
1250 | 12 | return AtomicOrdering::SequentiallyConsistent; |
1251 | 0 | } |
1252 | 0 | llvm_unreachable0 ("Unknown ordering"); |
1253 | 0 | } |
1254 | | |
1255 | 12 | AtomicOrdering addAcquireOrdering(AtomicOrdering a) { |
1256 | 12 | switch (a) { |
1257 | 0 | case AtomicOrdering::NotAtomic: |
1258 | 0 | return AtomicOrdering::NotAtomic; |
1259 | 9 | case AtomicOrdering::Unordered: |
1260 | 9 | case AtomicOrdering::Monotonic: |
1261 | 9 | case AtomicOrdering::Acquire: |
1262 | 9 | return AtomicOrdering::Acquire; |
1263 | 0 | case AtomicOrdering::Release: |
1264 | 0 | case AtomicOrdering::AcquireRelease: |
1265 | 0 | return AtomicOrdering::AcquireRelease; |
1266 | 3 | case AtomicOrdering::SequentiallyConsistent: |
1267 | 3 | return AtomicOrdering::SequentiallyConsistent; |
1268 | 0 | } |
1269 | 0 | llvm_unreachable0 ("Unknown ordering"); |
1270 | 0 | } |
1271 | | |
1272 | | // ------------------- Visitors. |
1273 | | |
1274 | | /// \brief Instrument LoadInst |
1275 | | /// |
1276 | | /// Loads the corresponding shadow and (optionally) origin. |
1277 | | /// Optionally, checks that the load address is fully defined. |
1278 | 107 | void visitLoadInst(LoadInst &I) { |
1279 | 107 | assert(I.getType()->isSized() && "Load type must have size"); |
1280 | 107 | IRBuilder<> IRB(I.getNextNode()); |
1281 | 107 | Type *ShadowTy = getShadowTy(&I); |
1282 | 107 | Value *Addr = I.getPointerOperand(); |
1283 | 107 | if (PropagateShadow && 107 !I.getMetadata("nosanitize")103 ) { |
1284 | 103 | Value *ShadowPtr = getShadowPtr(Addr, ShadowTy, IRB); |
1285 | 103 | setShadow(&I, |
1286 | 103 | IRB.CreateAlignedLoad(ShadowPtr, I.getAlignment(), "_msld")); |
1287 | 107 | } else { |
1288 | 4 | setShadow(&I, getCleanShadow(&I)); |
1289 | 4 | } |
1290 | 107 | |
1291 | 107 | if (ClCheckAccessAddress) |
1292 | 68 | insertShadowCheck(I.getPointerOperand(), &I); |
1293 | 107 | |
1294 | 107 | if (I.isAtomic()) |
1295 | 12 | I.setOrdering(addAcquireOrdering(I.getOrdering())); |
1296 | 107 | |
1297 | 107 | if (MS.TrackOrigins107 ) { |
1298 | 22 | if (PropagateShadow22 ) { |
1299 | 21 | unsigned Alignment = I.getAlignment(); |
1300 | 21 | unsigned OriginAlignment = std::max(kMinOriginAlignment, Alignment); |
1301 | 21 | setOrigin(&I, IRB.CreateAlignedLoad(getOriginPtr(Addr, IRB, Alignment), |
1302 | 21 | OriginAlignment)); |
1303 | 22 | } else { |
1304 | 1 | setOrigin(&I, getCleanOrigin()); |
1305 | 1 | } |
1306 | 22 | } |
1307 | 107 | } |
1308 | | |
1309 | | /// \brief Instrument StoreInst |
1310 | | /// |
1311 | | /// Stores the corresponding shadow and (optionally) origin. |
1312 | | /// Optionally, checks that the store address is fully defined. |
1313 | 126 | void visitStoreInst(StoreInst &I) { |
1314 | 126 | StoreList.push_back(&I); |
1315 | 126 | } |
1316 | | |
1317 | 12 | void handleCASOrRMW(Instruction &I) { |
1318 | 12 | assert(isa<AtomicRMWInst>(I) || isa<AtomicCmpXchgInst>(I)); |
1319 | 12 | |
1320 | 12 | IRBuilder<> IRB(&I); |
1321 | 12 | Value *Addr = I.getOperand(0); |
1322 | 12 | Value *ShadowPtr = getShadowPtr(Addr, I.getType(), IRB); |
1323 | 12 | |
1324 | 12 | if (ClCheckAccessAddress) |
1325 | 0 | insertShadowCheck(Addr, &I); |
1326 | 12 | |
1327 | 12 | // Only test the conditional argument of cmpxchg instruction. |
1328 | 12 | // The other argument can potentially be uninitialized, but we can not |
1329 | 12 | // detect this situation reliably without possible false positives. |
1330 | 12 | if (isa<AtomicCmpXchgInst>(I)) |
1331 | 6 | insertShadowCheck(I.getOperand(1), &I); |
1332 | 12 | |
1333 | 12 | IRB.CreateStore(getCleanShadow(&I), ShadowPtr); |
1334 | 12 | |
1335 | 12 | setShadow(&I, getCleanShadow(&I)); |
1336 | 12 | setOrigin(&I, getCleanOrigin()); |
1337 | 12 | } |
1338 | | |
1339 | 6 | void visitAtomicRMWInst(AtomicRMWInst &I) { |
1340 | 6 | handleCASOrRMW(I); |
1341 | 6 | I.setOrdering(addReleaseOrdering(I.getOrdering())); |
1342 | 6 | } |
1343 | | |
1344 | 6 | void visitAtomicCmpXchgInst(AtomicCmpXchgInst &I) { |
1345 | 6 | handleCASOrRMW(I); |
1346 | 6 | I.setSuccessOrdering(addReleaseOrdering(I.getSuccessOrdering())); |
1347 | 6 | } |
1348 | | |
1349 | | // Vector manipulation. |
1350 | 3 | void visitExtractElementInst(ExtractElementInst &I) { |
1351 | 3 | insertShadowCheck(I.getOperand(1), &I); |
1352 | 3 | IRBuilder<> IRB(&I); |
1353 | 3 | setShadow(&I, IRB.CreateExtractElement(getShadow(&I, 0), I.getOperand(1), |
1354 | 3 | "_msprop")); |
1355 | 3 | setOrigin(&I, getOrigin(&I, 0)); |
1356 | 3 | } |
1357 | | |
1358 | 12 | void visitInsertElementInst(InsertElementInst &I) { |
1359 | 12 | insertShadowCheck(I.getOperand(2), &I); |
1360 | 12 | IRBuilder<> IRB(&I); |
1361 | 12 | setShadow(&I, IRB.CreateInsertElement(getShadow(&I, 0), getShadow(&I, 1), |
1362 | 12 | I.getOperand(2), "_msprop")); |
1363 | 12 | setOriginForNaryOp(I); |
1364 | 12 | } |
1365 | | |
1366 | 3 | void visitShuffleVectorInst(ShuffleVectorInst &I) { |
1367 | 3 | insertShadowCheck(I.getOperand(2), &I); |
1368 | 3 | IRBuilder<> IRB(&I); |
1369 | 3 | setShadow(&I, IRB.CreateShuffleVector(getShadow(&I, 0), getShadow(&I, 1), |
1370 | 3 | I.getOperand(2), "_msprop")); |
1371 | 3 | setOriginForNaryOp(I); |
1372 | 3 | } |
1373 | | |
1374 | | // Casts. |
1375 | 2 | void visitSExtInst(SExtInst &I) { |
1376 | 2 | IRBuilder<> IRB(&I); |
1377 | 2 | setShadow(&I, IRB.CreateSExt(getShadow(&I, 0), I.getType(), "_msprop")); |
1378 | 2 | setOrigin(&I, getOrigin(&I, 0)); |
1379 | 2 | } |
1380 | | |
1381 | 0 | void visitZExtInst(ZExtInst &I) { |
1382 | 0 | IRBuilder<> IRB(&I); |
1383 | 0 | setShadow(&I, IRB.CreateZExt(getShadow(&I, 0), I.getType(), "_msprop")); |
1384 | 0 | setOrigin(&I, getOrigin(&I, 0)); |
1385 | 0 | } |
1386 | | |
1387 | 0 | void visitTruncInst(TruncInst &I) { |
1388 | 0 | IRBuilder<> IRB(&I); |
1389 | 0 | setShadow(&I, IRB.CreateTrunc(getShadow(&I, 0), I.getType(), "_msprop")); |
1390 | 0 | setOrigin(&I, getOrigin(&I, 0)); |
1391 | 0 | } |
1392 | | |
1393 | 109 | void visitBitCastInst(BitCastInst &I) { |
1394 | 109 | // Special case: if this is the bitcast (there is exactly 1 allowed) between |
1395 | 109 | // a musttail call and a ret, don't instrument. New instructions are not |
1396 | 109 | // allowed after a musttail call. |
1397 | 109 | if (auto *CI = dyn_cast<CallInst>(I.getOperand(0))) |
1398 | 4 | if (4 CI->isMustTailCall()4 ) |
1399 | 2 | return; |
1400 | 107 | IRBuilder<> IRB(&I); |
1401 | 107 | setShadow(&I, IRB.CreateBitCast(getShadow(&I, 0), getShadowTy(&I))); |
1402 | 107 | setOrigin(&I, getOrigin(&I, 0)); |
1403 | 107 | } |
1404 | | |
1405 | 0 | void visitPtrToIntInst(PtrToIntInst &I) { |
1406 | 0 | IRBuilder<> IRB(&I); |
1407 | 0 | setShadow(&I, IRB.CreateIntCast(getShadow(&I, 0), getShadowTy(&I), false, |
1408 | 0 | "_msprop_ptrtoint")); |
1409 | 0 | setOrigin(&I, getOrigin(&I, 0)); |
1410 | 0 | } |
1411 | | |
1412 | 5 | void visitIntToPtrInst(IntToPtrInst &I) { |
1413 | 5 | IRBuilder<> IRB(&I); |
1414 | 5 | setShadow(&I, IRB.CreateIntCast(getShadow(&I, 0), getShadowTy(&I), false, |
1415 | 5 | "_msprop_inttoptr")); |
1416 | 5 | setOrigin(&I, getOrigin(&I, 0)); |
1417 | 5 | } |
1418 | | |
1419 | 0 | void visitFPToSIInst(CastInst& I) { handleShadowOr(I); } |
1420 | 0 | void visitFPToUIInst(CastInst& I) { handleShadowOr(I); } |
1421 | 0 | void visitSIToFPInst(CastInst& I) { handleShadowOr(I); } |
1422 | 0 | void visitUIToFPInst(CastInst& I) { handleShadowOr(I); } |
1423 | 0 | void visitFPExtInst(CastInst& I) { handleShadowOr(I); } |
1424 | 0 | void visitFPTruncInst(CastInst& I) { handleShadowOr(I); } |
1425 | | |
1426 | | /// \brief Propagate shadow for bitwise AND. |
1427 | | /// |
1428 | | /// This code is exact, i.e. if, for example, a bit in the left argument |
1429 | | /// is defined and 0, then neither the value not definedness of the |
1430 | | /// corresponding bit in B don't affect the resulting shadow. |
1431 | 0 | void visitAnd(BinaryOperator &I) { |
1432 | 0 | IRBuilder<> IRB(&I); |
1433 | 0 | // "And" of 0 and a poisoned value results in unpoisoned value. |
1434 | 0 | // 1&1 => 1; 0&1 => 0; p&1 => p; |
1435 | 0 | // 1&0 => 0; 0&0 => 0; p&0 => 0; |
1436 | 0 | // 1&p => p; 0&p => 0; p&p => p; |
1437 | 0 | // S = (S1 & S2) | (V1 & S2) | (S1 & V2) |
1438 | 0 | Value *S1 = getShadow(&I, 0); |
1439 | 0 | Value *S2 = getShadow(&I, 1); |
1440 | 0 | Value *V1 = I.getOperand(0); |
1441 | 0 | Value *V2 = I.getOperand(1); |
1442 | 0 | if (V1->getType() != S1->getType()0 ) { |
1443 | 0 | V1 = IRB.CreateIntCast(V1, S1->getType(), false); |
1444 | 0 | V2 = IRB.CreateIntCast(V2, S2->getType(), false); |
1445 | 0 | } |
1446 | 0 | Value *S1S2 = IRB.CreateAnd(S1, S2); |
1447 | 0 | Value *V1S2 = IRB.CreateAnd(V1, S2); |
1448 | 0 | Value *S1V2 = IRB.CreateAnd(S1, V2); |
1449 | 0 | setShadow(&I, IRB.CreateOr(S1S2, IRB.CreateOr(V1S2, S1V2))); |
1450 | 0 | setOriginForNaryOp(I); |
1451 | 0 | } |
1452 | | |
1453 | 0 | void visitOr(BinaryOperator &I) { |
1454 | 0 | IRBuilder<> IRB(&I); |
1455 | 0 | // "Or" of 1 and a poisoned value results in unpoisoned value. |
1456 | 0 | // 1|1 => 1; 0|1 => 1; p|1 => 1; |
1457 | 0 | // 1|0 => 1; 0|0 => 0; p|0 => p; |
1458 | 0 | // 1|p => 1; 0|p => p; p|p => p; |
1459 | 0 | // S = (S1 & S2) | (~V1 & S2) | (S1 & ~V2) |
1460 | 0 | Value *S1 = getShadow(&I, 0); |
1461 | 0 | Value *S2 = getShadow(&I, 1); |
1462 | 0 | Value *V1 = IRB.CreateNot(I.getOperand(0)); |
1463 | 0 | Value *V2 = IRB.CreateNot(I.getOperand(1)); |
1464 | 0 | if (V1->getType() != S1->getType()0 ) { |
1465 | 0 | V1 = IRB.CreateIntCast(V1, S1->getType(), false); |
1466 | 0 | V2 = IRB.CreateIntCast(V2, S2->getType(), false); |
1467 | 0 | } |
1468 | 0 | Value *S1S2 = IRB.CreateAnd(S1, S2); |
1469 | 0 | Value *V1S2 = IRB.CreateAnd(V1, S2); |
1470 | 0 | Value *S1V2 = IRB.CreateAnd(S1, V2); |
1471 | 0 | setShadow(&I, IRB.CreateOr(S1S2, IRB.CreateOr(V1S2, S1V2))); |
1472 | 0 | setOriginForNaryOp(I); |
1473 | 0 | } |
1474 | | |
1475 | | /// \brief Default propagation of shadow and/or origin. |
1476 | | /// |
1477 | | /// This class implements the general case of shadow propagation, used in all |
1478 | | /// cases where we don't know and/or don't care about what the operation |
1479 | | /// actually does. It converts all input shadow values to a common type |
1480 | | /// (extending or truncating as necessary), and bitwise OR's them. |
1481 | | /// |
1482 | | /// This is much cheaper than inserting checks (i.e. requiring inputs to be |
1483 | | /// fully initialized), and less prone to false positives. |
1484 | | /// |
1485 | | /// This class also implements the general case of origin propagation. For a |
1486 | | /// Nary operation, result origin is set to the origin of an argument that is |
1487 | | /// not entirely initialized. If there is more than one such arguments, the |
1488 | | /// rightmost of them is picked. It does not matter which one is picked if all |
1489 | | /// arguments are initialized. |
1490 | | template <bool CombineShadow> |
1491 | | class Combiner { |
1492 | | Value *Shadow; |
1493 | | Value *Origin; |
1494 | | IRBuilder<> &IRB; |
1495 | | MemorySanitizerVisitor *MSV; |
1496 | | |
1497 | | public: |
1498 | | Combiner(MemorySanitizerVisitor *MSV, IRBuilder<> &IRB) : |
1499 | 103 | Shadow(nullptr), Origin(nullptr), IRB(IRB), MSV(MSV) {} MemorySanitizer.cpp:(anonymous namespace)::MemorySanitizerVisitor::Combiner<true>::Combiner((anonymous namespace)::MemorySanitizerVisitor*, llvm::IRBuilder<llvm::ConstantFolder, llvm::IRBuilderDefaultInserter>&) Line | Count | Source | 1499 | 77 | Shadow(nullptr), Origin(nullptr), IRB(IRB), MSV(MSV) {} |
MemorySanitizer.cpp:(anonymous namespace)::MemorySanitizerVisitor::Combiner<false>::Combiner((anonymous namespace)::MemorySanitizerVisitor*, llvm::IRBuilder<llvm::ConstantFolder, llvm::IRBuilderDefaultInserter>&) Line | Count | Source | 1499 | 26 | Shadow(nullptr), Origin(nullptr), IRB(IRB), MSV(MSV) {} |
|
1500 | | |
1501 | | /// \brief Add a pair of shadow and origin values to the mix. |
1502 | 251 | Combiner &Add(Value *OpShadow, Value *OpOrigin) { |
1503 | 251 | if (CombineShadow251 ) { |
1504 | 204 | assert(OpShadow); |
1505 | 204 | if (!Shadow) |
1506 | 77 | Shadow = OpShadow; |
1507 | 127 | else { |
1508 | 127 | OpShadow = MSV->CreateShadowCast(IRB, OpShadow, Shadow->getType()); |
1509 | 127 | Shadow = IRB.CreateOr(Shadow, OpShadow, "_msprop"); |
1510 | 127 | } |
1511 | 204 | } |
1512 | 251 | |
1513 | 251 | if (MSV->MS.TrackOrigins251 ) { |
1514 | 55 | assert(OpOrigin); |
1515 | 55 | if (!Origin55 ) { |
1516 | 29 | Origin = OpOrigin; |
1517 | 55 | } else { |
1518 | 26 | Constant *ConstOrigin = dyn_cast<Constant>(OpOrigin); |
1519 | 26 | // No point in adding something that might result in 0 origin value. |
1520 | 26 | if (!ConstOrigin || 26 !ConstOrigin->isNullValue()15 ) { |
1521 | 11 | Value *FlatShadow = MSV->convertToShadowTyNoVec(OpShadow, IRB); |
1522 | 11 | Value *Cond = |
1523 | 11 | IRB.CreateICmpNE(FlatShadow, MSV->getCleanShadow(FlatShadow)); |
1524 | 11 | Origin = IRB.CreateSelect(Cond, OpOrigin, Origin); |
1525 | 11 | } |
1526 | 26 | } |
1527 | 55 | } |
1528 | 251 | return *this; |
1529 | 251 | } MemorySanitizer.cpp:(anonymous namespace)::MemorySanitizerVisitor::Combiner<false>::Add(llvm::Value*, llvm::Value*) Line | Count | Source | 1502 | 47 | Combiner &Add(Value *OpShadow, Value *OpOrigin) { | 1503 | 47 | if (CombineShadow47 ) { | 1504 | 0 | assert(OpShadow); | 1505 | 0 | if (!Shadow) | 1506 | 0 | Shadow = OpShadow; | 1507 | 0 | else { | 1508 | 0 | OpShadow = MSV->CreateShadowCast(IRB, OpShadow, Shadow->getType()); | 1509 | 0 | Shadow = IRB.CreateOr(Shadow, OpShadow, "_msprop"); | 1510 | 0 | } | 1511 | 0 | } | 1512 | 47 | | 1513 | 47 | if (MSV->MS.TrackOrigins47 ) { | 1514 | 47 | assert(OpOrigin); | 1515 | 47 | if (!Origin47 ) { | 1516 | 26 | Origin = OpOrigin; | 1517 | 47 | } else { | 1518 | 21 | Constant *ConstOrigin = dyn_cast<Constant>(OpOrigin); | 1519 | 21 | // No point in adding something that might result in 0 origin value. | 1520 | 21 | if (!ConstOrigin || 21 !ConstOrigin->isNullValue()11 ) { | 1521 | 10 | Value *FlatShadow = MSV->convertToShadowTyNoVec(OpShadow, IRB); | 1522 | 10 | Value *Cond = | 1523 | 10 | IRB.CreateICmpNE(FlatShadow, MSV->getCleanShadow(FlatShadow)); | 1524 | 10 | Origin = IRB.CreateSelect(Cond, OpOrigin, Origin); | 1525 | 10 | } | 1526 | 21 | } | 1527 | 47 | } | 1528 | 47 | return *this; | 1529 | 47 | } |
MemorySanitizer.cpp:(anonymous namespace)::MemorySanitizerVisitor::Combiner<true>::Add(llvm::Value*, llvm::Value*) Line | Count | Source | 1502 | 204 | Combiner &Add(Value *OpShadow, Value *OpOrigin) { | 1503 | 204 | if (CombineShadow204 ) { | 1504 | 204 | assert(OpShadow); | 1505 | 204 | if (!Shadow) | 1506 | 77 | Shadow = OpShadow; | 1507 | 127 | else { | 1508 | 127 | OpShadow = MSV->CreateShadowCast(IRB, OpShadow, Shadow->getType()); | 1509 | 127 | Shadow = IRB.CreateOr(Shadow, OpShadow, "_msprop"); | 1510 | 127 | } | 1511 | 204 | } | 1512 | 204 | | 1513 | 204 | if (MSV->MS.TrackOrigins204 ) { | 1514 | 8 | assert(OpOrigin); | 1515 | 8 | if (!Origin8 ) { | 1516 | 3 | Origin = OpOrigin; | 1517 | 8 | } else { | 1518 | 5 | Constant *ConstOrigin = dyn_cast<Constant>(OpOrigin); | 1519 | 5 | // No point in adding something that might result in 0 origin value. | 1520 | 5 | if (!ConstOrigin || 5 !ConstOrigin->isNullValue()4 ) { | 1521 | 1 | Value *FlatShadow = MSV->convertToShadowTyNoVec(OpShadow, IRB); | 1522 | 1 | Value *Cond = | 1523 | 1 | IRB.CreateICmpNE(FlatShadow, MSV->getCleanShadow(FlatShadow)); | 1524 | 1 | Origin = IRB.CreateSelect(Cond, OpOrigin, Origin); | 1525 | 1 | } | 1526 | 5 | } | 1527 | 8 | } | 1528 | 204 | return *this; | 1529 | 204 | } |
|
1530 | | |
1531 | | /// \brief Add an application value to the mix. |
1532 | 251 | Combiner &Add(Value *V) { |
1533 | 251 | Value *OpShadow = MSV->getShadow(V); |
1534 | 251 | Value *OpOrigin = MSV->MS.TrackOrigins ? MSV->getOrigin(V)55 : nullptr196 ; |
1535 | 251 | return Add(OpShadow, OpOrigin); |
1536 | 251 | } MemorySanitizer.cpp:(anonymous namespace)::MemorySanitizerVisitor::Combiner<false>::Add(llvm::Value*) Line | Count | Source | 1532 | 47 | Combiner &Add(Value *V) { | 1533 | 47 | Value *OpShadow = MSV->getShadow(V); | 1534 | 47 | Value *OpOrigin = MSV->MS.TrackOrigins ? MSV->getOrigin(V)47 : nullptr0 ; | 1535 | 47 | return Add(OpShadow, OpOrigin); | 1536 | 47 | } |
MemorySanitizer.cpp:(anonymous namespace)::MemorySanitizerVisitor::Combiner<true>::Add(llvm::Value*) Line | Count | Source | 1532 | 204 | Combiner &Add(Value *V) { | 1533 | 204 | Value *OpShadow = MSV->getShadow(V); | 1534 | 204 | Value *OpOrigin = MSV->MS.TrackOrigins ? MSV->getOrigin(V)8 : nullptr196 ; | 1535 | 204 | return Add(OpShadow, OpOrigin); | 1536 | 204 | } |
|
1537 | | |
1538 | | /// \brief Set the current combined values as the given instruction's shadow |
1539 | | /// and origin. |
1540 | 103 | void Done(Instruction *I) { |
1541 | 103 | if (CombineShadow103 ) { |
1542 | 77 | assert(Shadow); |
1543 | 77 | Shadow = MSV->CreateShadowCast(IRB, Shadow, MSV->getShadowTy(I)); |
1544 | 77 | MSV->setShadow(I, Shadow); |
1545 | 77 | } |
1546 | 103 | if (MSV->MS.TrackOrigins103 ) { |
1547 | 29 | assert(Origin); |
1548 | 29 | MSV->setOrigin(I, Origin); |
1549 | 29 | } |
1550 | 103 | } MemorySanitizer.cpp:(anonymous namespace)::MemorySanitizerVisitor::Combiner<false>::Done(llvm::Instruction*) Line | Count | Source | 1540 | 26 | void Done(Instruction *I) { | 1541 | 26 | if (CombineShadow26 ) { | 1542 | 0 | assert(Shadow); | 1543 | 0 | Shadow = MSV->CreateShadowCast(IRB, Shadow, MSV->getShadowTy(I)); | 1544 | 0 | MSV->setShadow(I, Shadow); | 1545 | 0 | } | 1546 | 26 | if (MSV->MS.TrackOrigins26 ) { | 1547 | 26 | assert(Origin); | 1548 | 26 | MSV->setOrigin(I, Origin); | 1549 | 26 | } | 1550 | 26 | } |
MemorySanitizer.cpp:(anonymous namespace)::MemorySanitizerVisitor::Combiner<true>::Done(llvm::Instruction*) Line | Count | Source | 1540 | 77 | void Done(Instruction *I) { | 1541 | 77 | if (CombineShadow77 ) { | 1542 | 77 | assert(Shadow); | 1543 | 77 | Shadow = MSV->CreateShadowCast(IRB, Shadow, MSV->getShadowTy(I)); | 1544 | 77 | MSV->setShadow(I, Shadow); | 1545 | 77 | } | 1546 | 77 | if (MSV->MS.TrackOrigins77 ) { | 1547 | 3 | assert(Origin); | 1548 | 3 | MSV->setOrigin(I, Origin); | 1549 | 3 | } | 1550 | 77 | } |
|
1551 | | }; |
1552 | | |
1553 | | typedef Combiner<true> ShadowAndOriginCombiner; |
1554 | | typedef Combiner<false> OriginCombiner; |
1555 | | |
1556 | | /// \brief Propagate origin for arbitrary operation. |
1557 | 78 | void setOriginForNaryOp(Instruction &I) { |
1558 | 78 | if (!MS.TrackOrigins78 ) return52 ; |
1559 | 26 | IRBuilder<> IRB(&I); |
1560 | 26 | OriginCombiner OC(this, IRB); |
1561 | 73 | for (Instruction::op_iterator OI = I.op_begin(); OI != I.op_end()73 ; ++OI47 ) |
1562 | 47 | OC.Add(OI->get()); |
1563 | 78 | OC.Done(&I); |
1564 | 78 | } |
1565 | | |
1566 | 430 | size_t VectorOrPrimitiveTypeSizeInBits(Type *Ty) { |
1567 | 430 | assert(!(Ty->isVectorTy() && Ty->getScalarType()->isPointerTy()) && |
1568 | 430 | "Vector of pointers is not a valid shadow type"); |
1569 | 430 | return Ty->isVectorTy() ? |
1570 | 16 | Ty->getVectorNumElements() * Ty->getScalarSizeInBits() : |
1571 | 414 | Ty->getPrimitiveSizeInBits(); |
1572 | 430 | } |
1573 | | |
1574 | | /// \brief Cast between two shadow types, extending or truncating as |
1575 | | /// necessary. |
1576 | | Value *CreateShadowCast(IRBuilder<> &IRB, Value *V, Type *dstTy, |
1577 | 215 | bool Signed = false) { |
1578 | 215 | Type *srcTy = V->getType(); |
1579 | 215 | size_t srcSizeInBits = VectorOrPrimitiveTypeSizeInBits(srcTy); |
1580 | 215 | size_t dstSizeInBits = VectorOrPrimitiveTypeSizeInBits(dstTy); |
1581 | 215 | if (srcSizeInBits > 1 && 215 dstSizeInBits == 1206 ) |
1582 | 1 | return IRB.CreateICmpNE(V, getCleanShadow(V)); |
1583 | 214 | |
1584 | 214 | if (214 dstTy->isIntegerTy() && 214 srcTy->isIntegerTy()204 ) |
1585 | 202 | return IRB.CreateIntCast(V, dstTy, Signed); |
1586 | 12 | if (12 dstTy->isVectorTy() && 12 srcTy->isVectorTy()10 && |
1587 | 4 | dstTy->getVectorNumElements() == srcTy->getVectorNumElements()) |
1588 | 4 | return IRB.CreateIntCast(V, dstTy, Signed); |
1589 | 8 | Value *V1 = IRB.CreateBitCast(V, Type::getIntNTy(*MS.C, srcSizeInBits)); |
1590 | 8 | Value *V2 = |
1591 | 8 | IRB.CreateIntCast(V1, Type::getIntNTy(*MS.C, dstSizeInBits), Signed); |
1592 | 8 | return IRB.CreateBitCast(V2, dstTy); |
1593 | 8 | // TODO: handle struct types. |
1594 | 8 | } |
1595 | | |
1596 | | /// \brief Cast an application value to the type of its own shadow. |
1597 | 14 | Value *CreateAppToShadowCast(IRBuilder<> &IRB, Value *V) { |
1598 | 14 | Type *ShadowTy = getShadowTy(V); |
1599 | 14 | if (V->getType() == ShadowTy) |
1600 | 12 | return V; |
1601 | 2 | if (2 V->getType()->isPtrOrPtrVectorTy()2 ) |
1602 | 0 | return IRB.CreatePtrToInt(V, ShadowTy); |
1603 | 2 | else |
1604 | 2 | return IRB.CreateBitCast(V, ShadowTy); |
1605 | 0 | } |
1606 | | |
1607 | | /// \brief Propagate shadow for arbitrary operation. |
1608 | 75 | void handleShadowOr(Instruction &I) { |
1609 | 75 | IRBuilder<> IRB(&I); |
1610 | 75 | ShadowAndOriginCombiner SC(this, IRB); |
1611 | 275 | for (Instruction::op_iterator OI = I.op_begin(); OI != I.op_end()275 ; ++OI200 ) |
1612 | 200 | SC.Add(OI->get()); |
1613 | 75 | SC.Done(&I); |
1614 | 75 | } |
1615 | | |
1616 | | // \brief Handle multiplication by constant. |
1617 | | // |
1618 | | // Handle a special case of multiplication by constant that may have one or |
1619 | | // more zeros in the lower bits. This makes corresponding number of lower bits |
1620 | | // of the result zero as well. We model it by shifting the other operand |
1621 | | // shadow left by the required number of bits. Effectively, we transform |
1622 | | // (X * (A * 2**B)) to ((X << B) * A) and instrument (X << B) as (Sx << B). |
1623 | | // We use multiplication by 2**N instead of shift to cover the case of |
1624 | | // multiplication by 0, which may occur in some elements of a vector operand. |
1625 | | void handleMulByConstant(BinaryOperator &I, Constant *ConstArg, |
1626 | 9 | Value *OtherArg) { |
1627 | 9 | Constant *ShadowMul; |
1628 | 9 | Type *Ty = ConstArg->getType(); |
1629 | 9 | if (Ty->isVectorTy()9 ) { |
1630 | 2 | unsigned NumElements = Ty->getVectorNumElements(); |
1631 | 2 | Type *EltTy = Ty->getSequentialElementType(); |
1632 | 2 | SmallVector<Constant *, 16> Elements; |
1633 | 8 | for (unsigned Idx = 0; Idx < NumElements8 ; ++Idx6 ) { |
1634 | 6 | if (ConstantInt *Elt = |
1635 | 5 | dyn_cast<ConstantInt>(ConstArg->getAggregateElement(Idx))) { |
1636 | 5 | const APInt &V = Elt->getValue(); |
1637 | 5 | APInt V2 = APInt(V.getBitWidth(), 1) << V.countTrailingZeros(); |
1638 | 5 | Elements.push_back(ConstantInt::get(EltTy, V2)); |
1639 | 6 | } else { |
1640 | 1 | Elements.push_back(ConstantInt::get(EltTy, 1)); |
1641 | 1 | } |
1642 | 6 | } |
1643 | 2 | ShadowMul = ConstantVector::get(Elements); |
1644 | 9 | } else { |
1645 | 7 | if (ConstantInt *Elt7 = dyn_cast<ConstantInt>(ConstArg)) { |
1646 | 6 | const APInt &V = Elt->getValue(); |
1647 | 6 | APInt V2 = APInt(V.getBitWidth(), 1) << V.countTrailingZeros(); |
1648 | 6 | ShadowMul = ConstantInt::get(Ty, V2); |
1649 | 7 | } else { |
1650 | 1 | ShadowMul = ConstantInt::get(Ty, 1); |
1651 | 1 | } |
1652 | 7 | } |
1653 | 9 | |
1654 | 9 | IRBuilder<> IRB(&I); |
1655 | 9 | setShadow(&I, |
1656 | 9 | IRB.CreateMul(getShadow(OtherArg), ShadowMul, "msprop_mul_cst")); |
1657 | 9 | setOrigin(&I, getOrigin(OtherArg)); |
1658 | 9 | } |
1659 | | |
1660 | 9 | void visitMul(BinaryOperator &I) { |
1661 | 9 | Constant *constOp0 = dyn_cast<Constant>(I.getOperand(0)); |
1662 | 9 | Constant *constOp1 = dyn_cast<Constant>(I.getOperand(1)); |
1663 | 9 | if (constOp0 && 9 !constOp10 ) |
1664 | 0 | handleMulByConstant(I, constOp0, I.getOperand(1)); |
1665 | 9 | else if (9 constOp1 && 9 !constOp09 ) |
1666 | 9 | handleMulByConstant(I, constOp1, I.getOperand(0)); |
1667 | 9 | else |
1668 | 0 | handleShadowOr(I); |
1669 | 9 | } |
1670 | | |
1671 | 0 | void visitFAdd(BinaryOperator &I) { handleShadowOr(I); } |
1672 | 0 | void visitFSub(BinaryOperator &I) { handleShadowOr(I); } |
1673 | 0 | void visitFMul(BinaryOperator &I) { handleShadowOr(I); } |
1674 | 2 | void visitAdd(BinaryOperator &I) { handleShadowOr(I); } |
1675 | 0 | void visitSub(BinaryOperator &I) { handleShadowOr(I); } |
1676 | 0 | void visitXor(BinaryOperator &I) { handleShadowOr(I); } |
1677 | | |
1678 | 2 | void handleDiv(Instruction &I) { |
1679 | 2 | IRBuilder<> IRB(&I); |
1680 | 2 | // Strict on the second argument. |
1681 | 2 | insertShadowCheck(I.getOperand(1), &I); |
1682 | 2 | setShadow(&I, getShadow(&I, 0)); |
1683 | 2 | setOrigin(&I, getOrigin(&I, 0)); |
1684 | 2 | } |
1685 | | |
1686 | 2 | void visitUDiv(BinaryOperator &I) { handleDiv(I); } |
1687 | 0 | void visitSDiv(BinaryOperator &I) { handleDiv(I); } |
1688 | 0 | void visitFDiv(BinaryOperator &I) { handleDiv(I); } |
1689 | 0 | void visitURem(BinaryOperator &I) { handleDiv(I); } |
1690 | 0 | void visitSRem(BinaryOperator &I) { handleDiv(I); } |
1691 | 0 | void visitFRem(BinaryOperator &I) { handleDiv(I); } |
1692 | | |
1693 | | /// \brief Instrument == and != comparisons. |
1694 | | /// |
1695 | | /// Sometimes the comparison result is known even if some of the bits of the |
1696 | | /// arguments are not. |
1697 | 11 | void handleEqualityComparison(ICmpInst &I) { |
1698 | 11 | IRBuilder<> IRB(&I); |
1699 | 11 | Value *A = I.getOperand(0); |
1700 | 11 | Value *B = I.getOperand(1); |
1701 | 11 | Value *Sa = getShadow(A); |
1702 | 11 | Value *Sb = getShadow(B); |
1703 | 11 | |
1704 | 11 | // Get rid of pointers and vectors of pointers. |
1705 | 11 | // For ints (and vectors of ints), types of A and Sa match, |
1706 | 11 | // and this is a no-op. |
1707 | 11 | A = IRB.CreatePointerCast(A, Sa->getType()); |
1708 | 11 | B = IRB.CreatePointerCast(B, Sb->getType()); |
1709 | 11 | |
1710 | 11 | // A == B <==> (C = A^B) == 0 |
1711 | 11 | // A != B <==> (C = A^B) != 0 |
1712 | 11 | // Sc = Sa | Sb |
1713 | 11 | Value *C = IRB.CreateXor(A, B); |
1714 | 11 | Value *Sc = IRB.CreateOr(Sa, Sb); |
1715 | 11 | // Now dealing with i = (C == 0) comparison (or C != 0, does not matter now) |
1716 | 11 | // Result is defined if one of the following is true |
1717 | 11 | // * there is a defined 1 bit in C |
1718 | 11 | // * C is fully defined |
1719 | 11 | // Si = !(C & ~Sc) && Sc |
1720 | 11 | Value *Zero = Constant::getNullValue(Sc->getType()); |
1721 | 11 | Value *MinusOne = Constant::getAllOnesValue(Sc->getType()); |
1722 | 11 | Value *Si = |
1723 | 11 | IRB.CreateAnd(IRB.CreateICmpNE(Sc, Zero), |
1724 | 11 | IRB.CreateICmpEQ( |
1725 | 11 | IRB.CreateAnd(IRB.CreateXor(Sc, MinusOne), C), Zero)); |
1726 | 11 | Si->setName("_msprop_icmp"); |
1727 | 11 | setShadow(&I, Si); |
1728 | 11 | setOriginForNaryOp(I); |
1729 | 11 | } |
1730 | | |
1731 | | /// \brief Build the lowest possible value of V, taking into account V's |
1732 | | /// uninitialized bits. |
1733 | | Value *getLowestPossibleValue(IRBuilder<> &IRB, Value *A, Value *Sa, |
1734 | 4 | bool isSigned) { |
1735 | 4 | if (isSigned4 ) { |
1736 | 0 | // Split shadow into sign bit and other bits. |
1737 | 0 | Value *SaOtherBits = IRB.CreateLShr(IRB.CreateShl(Sa, 1), 1); |
1738 | 0 | Value *SaSignBit = IRB.CreateXor(Sa, SaOtherBits); |
1739 | 0 | // Maximise the undefined shadow bit, minimize other undefined bits. |
1740 | 0 | return |
1741 | 0 | IRB.CreateOr(IRB.CreateAnd(A, IRB.CreateNot(SaOtherBits)), SaSignBit); |
1742 | 0 | } else { |
1743 | 4 | // Minimize undefined bits. |
1744 | 4 | return IRB.CreateAnd(A, IRB.CreateNot(Sa)); |
1745 | 4 | } |
1746 | 0 | } |
1747 | | |
1748 | | /// \brief Build the highest possible value of V, taking into account V's |
1749 | | /// uninitialized bits. |
1750 | | Value *getHighestPossibleValue(IRBuilder<> &IRB, Value *A, Value *Sa, |
1751 | 4 | bool isSigned) { |
1752 | 4 | if (isSigned4 ) { |
1753 | 0 | // Split shadow into sign bit and other bits. |
1754 | 0 | Value *SaOtherBits = IRB.CreateLShr(IRB.CreateShl(Sa, 1), 1); |
1755 | 0 | Value *SaSignBit = IRB.CreateXor(Sa, SaOtherBits); |
1756 | 0 | // Minimise the undefined shadow bit, maximise other undefined bits. |
1757 | 0 | return |
1758 | 0 | IRB.CreateOr(IRB.CreateAnd(A, IRB.CreateNot(SaSignBit)), SaOtherBits); |
1759 | 0 | } else { |
1760 | 4 | // Maximize undefined bits. |
1761 | 4 | return IRB.CreateOr(A, Sa); |
1762 | 4 | } |
1763 | 0 | } |
1764 | | |
1765 | | /// \brief Instrument relational comparisons. |
1766 | | /// |
1767 | | /// This function does exact shadow propagation for all relational |
1768 | | /// comparisons of integers, pointers and vectors of those. |
1769 | | /// FIXME: output seems suboptimal when one of the operands is a constant |
1770 | 2 | void handleRelationalComparisonExact(ICmpInst &I) { |
1771 | 2 | IRBuilder<> IRB(&I); |
1772 | 2 | Value *A = I.getOperand(0); |
1773 | 2 | Value *B = I.getOperand(1); |
1774 | 2 | Value *Sa = getShadow(A); |
1775 | 2 | Value *Sb = getShadow(B); |
1776 | 2 | |
1777 | 2 | // Get rid of pointers and vectors of pointers. |
1778 | 2 | // For ints (and vectors of ints), types of A and Sa match, |
1779 | 2 | // and this is a no-op. |
1780 | 2 | A = IRB.CreatePointerCast(A, Sa->getType()); |
1781 | 2 | B = IRB.CreatePointerCast(B, Sb->getType()); |
1782 | 2 | |
1783 | 2 | // Let [a0, a1] be the interval of possible values of A, taking into account |
1784 | 2 | // its undefined bits. Let [b0, b1] be the interval of possible values of B. |
1785 | 2 | // Then (A cmp B) is defined iff (a0 cmp b1) == (a1 cmp b0). |
1786 | 2 | bool IsSigned = I.isSigned(); |
1787 | 2 | Value *S1 = IRB.CreateICmp(I.getPredicate(), |
1788 | 2 | getLowestPossibleValue(IRB, A, Sa, IsSigned), |
1789 | 2 | getHighestPossibleValue(IRB, B, Sb, IsSigned)); |
1790 | 2 | Value *S2 = IRB.CreateICmp(I.getPredicate(), |
1791 | 2 | getHighestPossibleValue(IRB, A, Sa, IsSigned), |
1792 | 2 | getLowestPossibleValue(IRB, B, Sb, IsSigned)); |
1793 | 2 | Value *Si = IRB.CreateXor(S1, S2); |
1794 | 2 | setShadow(&I, Si); |
1795 | 2 | setOriginForNaryOp(I); |
1796 | 2 | } |
1797 | | |
1798 | | /// \brief Instrument signed relational comparisons. |
1799 | | /// |
1800 | | /// Handle sign bit tests: x<0, x>=0, x<=-1, x>-1 by propagating the highest |
1801 | | /// bit of the shadow. Everything else is delegated to handleShadowOr(). |
1802 | 21 | void handleSignedRelationalComparison(ICmpInst &I) { |
1803 | 21 | Constant *constOp; |
1804 | 21 | Value *op = nullptr; |
1805 | 21 | CmpInst::Predicate pre; |
1806 | 21 | if ((constOp = dyn_cast<Constant>(I.getOperand(1)))21 ) { |
1807 | 10 | op = I.getOperand(0); |
1808 | 10 | pre = I.getPredicate(); |
1809 | 21 | } else if (11 (constOp = dyn_cast<Constant>(I.getOperand(0)))11 ) { |
1810 | 10 | op = I.getOperand(1); |
1811 | 10 | pre = I.getSwappedPredicate(); |
1812 | 11 | } else { |
1813 | 1 | handleShadowOr(I); |
1814 | 1 | return; |
1815 | 1 | } |
1816 | 20 | |
1817 | 20 | if (20 (constOp->isNullValue() && |
1818 | 10 | (pre == CmpInst::ICMP_SLT || 10 pre == CmpInst::ICMP_SGE4 )) || |
1819 | 10 | (constOp->isAllOnesValue() && |
1820 | 20 | (pre == CmpInst::ICMP_SGT || 10 pre == CmpInst::ICMP_SLE4 ))) { |
1821 | 20 | IRBuilder<> IRB(&I); |
1822 | 20 | Value *Shadow = IRB.CreateICmpSLT(getShadow(op), getCleanShadow(op), |
1823 | 20 | "_msprop_icmp_s"); |
1824 | 20 | setShadow(&I, Shadow); |
1825 | 20 | setOrigin(&I, getOrigin(op)); |
1826 | 20 | } else { |
1827 | 0 | handleShadowOr(I); |
1828 | 0 | } |
1829 | 21 | } |
1830 | | |
1831 | 34 | void visitICmpInst(ICmpInst &I) { |
1832 | 34 | if (!ClHandleICmp34 ) { |
1833 | 0 | handleShadowOr(I); |
1834 | 0 | return; |
1835 | 0 | } |
1836 | 34 | if (34 I.isEquality()34 ) { |
1837 | 11 | handleEqualityComparison(I); |
1838 | 11 | return; |
1839 | 11 | } |
1840 | 23 | |
1841 | 34 | assert(I.isRelational()); |
1842 | 23 | if (ClHandleICmpExact23 ) { |
1843 | 0 | handleRelationalComparisonExact(I); |
1844 | 0 | return; |
1845 | 0 | } |
1846 | 23 | if (23 I.isSigned()23 ) { |
1847 | 21 | handleSignedRelationalComparison(I); |
1848 | 21 | return; |
1849 | 21 | } |
1850 | 2 | |
1851 | 23 | assert(I.isUnsigned()); |
1852 | 2 | if ((isa<Constant>(I.getOperand(0)) || 2 isa<Constant>(I.getOperand(1))2 )) { |
1853 | 2 | handleRelationalComparisonExact(I); |
1854 | 2 | return; |
1855 | 2 | } |
1856 | 0 |
|
1857 | 0 | handleShadowOr(I); |
1858 | 0 | } |
1859 | | |
1860 | 0 | void visitFCmpInst(FCmpInst &I) { |
1861 | 0 | handleShadowOr(I); |
1862 | 0 | } |
1863 | | |
1864 | 4 | void handleShift(BinaryOperator &I) { |
1865 | 4 | IRBuilder<> IRB(&I); |
1866 | 4 | // If any of the S2 bits are poisoned, the whole thing is poisoned. |
1867 | 4 | // Otherwise perform the same shift on S1. |
1868 | 4 | Value *S1 = getShadow(&I, 0); |
1869 | 4 | Value *S2 = getShadow(&I, 1); |
1870 | 4 | Value *S2Conv = IRB.CreateSExt(IRB.CreateICmpNE(S2, getCleanShadow(S2)), |
1871 | 4 | S2->getType()); |
1872 | 4 | Value *V2 = I.getOperand(1); |
1873 | 4 | Value *Shift = IRB.CreateBinOp(I.getOpcode(), S1, V2); |
1874 | 4 | setShadow(&I, IRB.CreateOr(Shift, S2Conv)); |
1875 | 4 | setOriginForNaryOp(I); |
1876 | 4 | } |
1877 | | |
1878 | 4 | void visitShl(BinaryOperator &I) { handleShift(I); } |
1879 | 0 | void visitAShr(BinaryOperator &I) { handleShift(I); } |
1880 | 0 | void visitLShr(BinaryOperator &I) { handleShift(I); } |
1881 | | |
1882 | | /// \brief Instrument llvm.memmove |
1883 | | /// |
1884 | | /// At this point we don't know if llvm.memmove will be inlined or not. |
1885 | | /// If we don't instrument it and it gets inlined, |
1886 | | /// our interceptor will not kick in and we will lose the memmove. |
1887 | | /// If we instrument the call here, but it does not get inlined, |
1888 | | /// we will memove the shadow twice: which is bad in case |
1889 | | /// of overlapping regions. So, we simply lower the intrinsic to a call. |
1890 | | /// |
1891 | | /// Similar situation exists for memcpy and memset. |
1892 | 2 | void visitMemMoveInst(MemMoveInst &I) { |
1893 | 2 | IRBuilder<> IRB(&I); |
1894 | 2 | IRB.CreateCall( |
1895 | 2 | MS.MemmoveFn, |
1896 | 2 | {IRB.CreatePointerCast(I.getArgOperand(0), IRB.getInt8PtrTy()), |
1897 | 2 | IRB.CreatePointerCast(I.getArgOperand(1), IRB.getInt8PtrTy()), |
1898 | 2 | IRB.CreateIntCast(I.getArgOperand(2), MS.IntptrTy, false)}); |
1899 | 2 | I.eraseFromParent(); |
1900 | 2 | } |
1901 | | |
1902 | | // Similar to memmove: avoid copying shadow twice. |
1903 | | // This is somewhat unfortunate as it may slowdown small constant memcpys. |
1904 | | // FIXME: consider doing manual inline for small constant sizes and proper |
1905 | | // alignment. |
1906 | 4 | void visitMemCpyInst(MemCpyInst &I) { |
1907 | 4 | IRBuilder<> IRB(&I); |
1908 | 4 | IRB.CreateCall( |
1909 | 4 | MS.MemcpyFn, |
1910 | 4 | {IRB.CreatePointerCast(I.getArgOperand(0), IRB.getInt8PtrTy()), |
1911 | 4 | IRB.CreatePointerCast(I.getArgOperand(1), IRB.getInt8PtrTy()), |
1912 | 4 | IRB.CreateIntCast(I.getArgOperand(2), MS.IntptrTy, false)}); |
1913 | 4 | I.eraseFromParent(); |
1914 | 4 | } |
1915 | | |
1916 | | // Same as memcpy. |
1917 | 2 | void visitMemSetInst(MemSetInst &I) { |
1918 | 2 | IRBuilder<> IRB(&I); |
1919 | 2 | IRB.CreateCall( |
1920 | 2 | MS.MemsetFn, |
1921 | 2 | {IRB.CreatePointerCast(I.getArgOperand(0), IRB.getInt8PtrTy()), |
1922 | 2 | IRB.CreateIntCast(I.getArgOperand(1), IRB.getInt32Ty(), false), |
1923 | 2 | IRB.CreateIntCast(I.getArgOperand(2), MS.IntptrTy, false)}); |
1924 | 2 | I.eraseFromParent(); |
1925 | 2 | } |
1926 | | |
1927 | 8 | void visitVAStartInst(VAStartInst &I) { |
1928 | 8 | VAHelper->visitVAStartInst(I); |
1929 | 8 | } |
1930 | | |
1931 | 2 | void visitVACopyInst(VACopyInst &I) { |
1932 | 2 | VAHelper->visitVACopyInst(I); |
1933 | 2 | } |
1934 | | |
1935 | | /// \brief Handle vector store-like intrinsics. |
1936 | | /// |
1937 | | /// Instrument intrinsics that look like a simple SIMD store: writes memory, |
1938 | | /// has 1 pointer argument and 1 vector argument, returns void. |
1939 | 0 | bool handleVectorStoreIntrinsic(IntrinsicInst &I) { |
1940 | 0 | IRBuilder<> IRB(&I); |
1941 | 0 | Value* Addr = I.getArgOperand(0); |
1942 | 0 | Value *Shadow = getShadow(&I, 1); |
1943 | 0 | Value *ShadowPtr = getShadowPtr(Addr, Shadow->getType(), IRB); |
1944 | 0 |
|
1945 | 0 | // We don't know the pointer alignment (could be unaligned SSE store!). |
1946 | 0 | // Have to assume to worst case. |
1947 | 0 | IRB.CreateAlignedStore(Shadow, ShadowPtr, 1); |
1948 | 0 |
|
1949 | 0 | if (ClCheckAccessAddress) |
1950 | 0 | insertShadowCheck(Addr, &I); |
1951 | 0 |
|
1952 | 0 | // FIXME: factor out common code from materializeStores |
1953 | 0 | if (MS.TrackOrigins) |
1954 | 0 | IRB.CreateStore(getOrigin(&I, 1), getOriginPtr(Addr, IRB, 1)); |
1955 | 0 | return true; |
1956 | 0 | } |
1957 | | |
1958 | | /// \brief Handle vector load-like intrinsics. |
1959 | | /// |
1960 | | /// Instrument intrinsics that look like a simple SIMD load: reads memory, |
1961 | | /// has 1 pointer argument, returns a vector. |
1962 | 2 | bool handleVectorLoadIntrinsic(IntrinsicInst &I) { |
1963 | 2 | IRBuilder<> IRB(&I); |
1964 | 2 | Value *Addr = I.getArgOperand(0); |
1965 | 2 | |
1966 | 2 | Type *ShadowTy = getShadowTy(&I); |
1967 | 2 | if (PropagateShadow2 ) { |
1968 | 2 | Value *ShadowPtr = getShadowPtr(Addr, ShadowTy, IRB); |
1969 | 2 | // We don't know the pointer alignment (could be unaligned SSE load!). |
1970 | 2 | // Have to assume to worst case. |
1971 | 2 | setShadow(&I, IRB.CreateAlignedLoad(ShadowPtr, 1, "_msld")); |
1972 | 2 | } else { |
1973 | 0 | setShadow(&I, getCleanShadow(&I)); |
1974 | 0 | } |
1975 | 2 | |
1976 | 2 | if (ClCheckAccessAddress) |
1977 | 0 | insertShadowCheck(Addr, &I); |
1978 | 2 | |
1979 | 2 | if (MS.TrackOrigins2 ) { |
1980 | 1 | if (PropagateShadow) |
1981 | 1 | setOrigin(&I, IRB.CreateLoad(getOriginPtr(Addr, IRB, 1))); |
1982 | 1 | else |
1983 | 0 | setOrigin(&I, getCleanOrigin()); |
1984 | 1 | } |
1985 | 2 | return true; |
1986 | 2 | } |
1987 | | |
1988 | | /// \brief Handle (SIMD arithmetic)-like intrinsics. |
1989 | | /// |
1990 | | /// Instrument intrinsics with any number of arguments of the same type, |
1991 | | /// equal to the return type. The type should be simple (no aggregates or |
1992 | | /// pointers; vectors are fine). |
1993 | | /// Caller guarantees that this intrinsic does not access memory. |
1994 | 6 | bool maybeHandleSimpleNomemIntrinsic(IntrinsicInst &I) { |
1995 | 6 | Type *RetTy = I.getType(); |
1996 | 6 | if (!(RetTy->isIntOrIntVectorTy() || |
1997 | 4 | RetTy->isFPOrFPVectorTy() || |
1998 | 4 | RetTy->isX86_MMXTy())) |
1999 | 4 | return false; |
2000 | 2 | |
2001 | 2 | unsigned NumArgOperands = I.getNumArgOperands(); |
2002 | 2 | |
2003 | 6 | for (unsigned i = 0; i < NumArgOperands6 ; ++i4 ) { |
2004 | 4 | Type *Ty = I.getArgOperand(i)->getType(); |
2005 | 4 | if (Ty != RetTy) |
2006 | 0 | return false; |
2007 | 4 | } |
2008 | 2 | |
2009 | 2 | IRBuilder<> IRB(&I); |
2010 | 2 | ShadowAndOriginCombiner SC(this, IRB); |
2011 | 6 | for (unsigned i = 0; i < NumArgOperands6 ; ++i4 ) |
2012 | 4 | SC.Add(I.getArgOperand(i)); |
2013 | 2 | SC.Done(&I); |
2014 | 2 | |
2015 | 2 | return true; |
2016 | 6 | } |
2017 | | |
2018 | | /// \brief Heuristically instrument unknown intrinsics. |
2019 | | /// |
2020 | | /// The main purpose of this code is to do something reasonable with all |
2021 | | /// random intrinsics we might encounter, most importantly - SIMD intrinsics. |
2022 | | /// We recognize several classes of intrinsics by their argument types and |
2023 | | /// ModRefBehaviour and apply special intrumentation when we are reasonably |
2024 | | /// sure that we know what the intrinsic does. |
2025 | | /// |
2026 | | /// We special-case intrinsics where this approach fails. See llvm.bswap |
2027 | | /// handling as an example of that. |
2028 | 31 | bool handleUnknownIntrinsic(IntrinsicInst &I) { |
2029 | 31 | unsigned NumArgOperands = I.getNumArgOperands(); |
2030 | 31 | if (NumArgOperands == 0) |
2031 | 0 | return false; |
2032 | 31 | |
2033 | 31 | if (31 NumArgOperands == 2 && |
2034 | 12 | I.getArgOperand(0)->getType()->isPointerTy() && |
2035 | 0 | I.getArgOperand(1)->getType()->isVectorTy() && |
2036 | 0 | I.getType()->isVoidTy() && |
2037 | 31 | !I.onlyReadsMemory()0 ) { |
2038 | 0 | // This looks like a vector store. |
2039 | 0 | return handleVectorStoreIntrinsic(I); |
2040 | 0 | } |
2041 | 31 | |
2042 | 31 | if (31 NumArgOperands == 1 && |
2043 | 8 | I.getArgOperand(0)->getType()->isPointerTy() && |
2044 | 7 | I.getType()->isVectorTy() && |
2045 | 31 | I.onlyReadsMemory()2 ) { |
2046 | 2 | // This looks like a vector load. |
2047 | 2 | return handleVectorLoadIntrinsic(I); |
2048 | 2 | } |
2049 | 29 | |
2050 | 29 | if (29 I.doesNotAccessMemory()29 ) |
2051 | 6 | if (6 maybeHandleSimpleNomemIntrinsic(I)6 ) |
2052 | 2 | return true; |
2053 | 27 | |
2054 | 27 | // FIXME: detect and handle SSE maskstore/maskload |
2055 | 27 | return false; |
2056 | 27 | } |
2057 | | |
2058 | 2 | void handleBswap(IntrinsicInst &I) { |
2059 | 2 | IRBuilder<> IRB(&I); |
2060 | 2 | Value *Op = I.getArgOperand(0); |
2061 | 2 | Type *OpType = Op->getType(); |
2062 | 2 | Function *BswapFunc = Intrinsic::getDeclaration( |
2063 | 2 | F.getParent(), Intrinsic::bswap, makeArrayRef(&OpType, 1)); |
2064 | 2 | setShadow(&I, IRB.CreateCall(BswapFunc, getShadow(Op))); |
2065 | 2 | setOrigin(&I, getOrigin(Op)); |
2066 | 2 | } |
2067 | | |
2068 | | // \brief Instrument vector convert instrinsic. |
2069 | | // |
2070 | | // This function instruments intrinsics like cvtsi2ss: |
2071 | | // %Out = int_xxx_cvtyyy(%ConvertOp) |
2072 | | // or |
2073 | | // %Out = int_xxx_cvtyyy(%CopyOp, %ConvertOp) |
2074 | | // Intrinsic converts \p NumUsedElements elements of \p ConvertOp to the same |
2075 | | // number \p Out elements, and (if has 2 arguments) copies the rest of the |
2076 | | // elements from \p CopyOp. |
2077 | | // In most cases conversion involves floating-point value which may trigger a |
2078 | | // hardware exception when not fully initialized. For this reason we require |
2079 | | // \p ConvertOp[0:NumUsedElements] to be fully initialized and trap otherwise. |
2080 | | // We copy the shadow of \p CopyOp[NumUsedElements:] to \p |
2081 | | // Out[NumUsedElements:]. This means that intrinsics without \p CopyOp always |
2082 | | // return a fully initialized value. |
2083 | 3 | void handleVectorConvertIntrinsic(IntrinsicInst &I, int NumUsedElements) { |
2084 | 3 | IRBuilder<> IRB(&I); |
2085 | 3 | Value *CopyOp, *ConvertOp; |
2086 | 3 | |
2087 | 3 | switch (I.getNumArgOperands()) { |
2088 | 0 | case 3: |
2089 | 0 | assert(isa<ConstantInt>(I.getArgOperand(2)) && "Invalid rounding mode"); |
2090 | 0 | LLVM_FALLTHROUGH; |
2091 | 1 | case 2: |
2092 | 1 | CopyOp = I.getArgOperand(0); |
2093 | 1 | ConvertOp = I.getArgOperand(1); |
2094 | 1 | break; |
2095 | 2 | case 1: |
2096 | 2 | ConvertOp = I.getArgOperand(0); |
2097 | 2 | CopyOp = nullptr; |
2098 | 2 | break; |
2099 | 0 | default: |
2100 | 0 | llvm_unreachable("Cvt intrinsic with unsupported number of arguments."); |
2101 | 3 | } |
2102 | 3 | |
2103 | 3 | // The first *NumUsedElements* elements of ConvertOp are converted to the |
2104 | 3 | // same number of output elements. The rest of the output is copied from |
2105 | 3 | // CopyOp, or (if not available) filled with zeroes. |
2106 | 3 | // Combine shadow for elements of ConvertOp that are used in this operation, |
2107 | 3 | // and insert a check. |
2108 | 3 | // FIXME: consider propagating shadow of ConvertOp, at least in the case of |
2109 | 3 | // int->any conversion. |
2110 | 3 | Value *ConvertShadow = getShadow(ConvertOp); |
2111 | 3 | Value *AggShadow = nullptr; |
2112 | 3 | if (ConvertOp->getType()->isVectorTy()3 ) { |
2113 | 2 | AggShadow = IRB.CreateExtractElement( |
2114 | 2 | ConvertShadow, ConstantInt::get(IRB.getInt32Ty(), 0)); |
2115 | 3 | for (int i = 1; i < NumUsedElements3 ; ++i1 ) { |
2116 | 1 | Value *MoreShadow = IRB.CreateExtractElement( |
2117 | 1 | ConvertShadow, ConstantInt::get(IRB.getInt32Ty(), i)); |
2118 | 1 | AggShadow = IRB.CreateOr(AggShadow, MoreShadow); |
2119 | 1 | } |
2120 | 3 | } else { |
2121 | 1 | AggShadow = ConvertShadow; |
2122 | 1 | } |
2123 | 3 | assert(AggShadow->getType()->isIntegerTy()); |
2124 | 3 | insertShadowCheck(AggShadow, getOrigin(ConvertOp), &I); |
2125 | 3 | |
2126 | 3 | // Build result shadow by zero-filling parts of CopyOp shadow that come from |
2127 | 3 | // ConvertOp. |
2128 | 3 | if (CopyOp3 ) { |
2129 | 1 | assert(CopyOp->getType() == I.getType()); |
2130 | 1 | assert(CopyOp->getType()->isVectorTy()); |
2131 | 1 | Value *ResultShadow = getShadow(CopyOp); |
2132 | 1 | Type *EltTy = ResultShadow->getType()->getVectorElementType(); |
2133 | 2 | for (int i = 0; i < NumUsedElements2 ; ++i1 ) { |
2134 | 1 | ResultShadow = IRB.CreateInsertElement( |
2135 | 1 | ResultShadow, ConstantInt::getNullValue(EltTy), |
2136 | 1 | ConstantInt::get(IRB.getInt32Ty(), i)); |
2137 | 1 | } |
2138 | 1 | setShadow(&I, ResultShadow); |
2139 | 1 | setOrigin(&I, getOrigin(CopyOp)); |
2140 | 3 | } else { |
2141 | 2 | setShadow(&I, getCleanShadow(&I)); |
2142 | 2 | setOrigin(&I, getCleanOrigin()); |
2143 | 2 | } |
2144 | 3 | } |
2145 | | |
2146 | | // Given a scalar or vector, extract lower 64 bits (or less), and return all |
2147 | | // zeroes if it is zero, and all ones otherwise. |
2148 | 5 | Value *Lower64ShadowExtend(IRBuilder<> &IRB, Value *S, Type *T) { |
2149 | 5 | if (S->getType()->isVectorTy()) |
2150 | 2 | S = CreateShadowCast(IRB, S, IRB.getInt64Ty(), /* Signed */ true); |
2151 | 5 | assert(S->getType()->getPrimitiveSizeInBits() <= 64); |
2152 | 5 | Value *S2 = IRB.CreateICmpNE(S, getCleanShadow(S)); |
2153 | 5 | return CreateShadowCast(IRB, S2, T, /* Signed */ true); |
2154 | 5 | } |
2155 | | |
2156 | | // Given a vector, extract its first element, and return all |
2157 | | // zeroes if it is zero, and all ones otherwise. |
2158 | 4 | Value *LowerElementShadowExtend(IRBuilder<> &IRB, Value *S, Type *T) { |
2159 | 4 | Value *S1 = IRB.CreateExtractElement(S, (uint64_t)0); |
2160 | 4 | Value *S2 = IRB.CreateICmpNE(S1, getCleanShadow(S1)); |
2161 | 4 | return CreateShadowCast(IRB, S2, T, /* Signed */ true); |
2162 | 4 | } |
2163 | | |
2164 | 3 | Value *VariableShadowExtend(IRBuilder<> &IRB, Value *S) { |
2165 | 3 | Type *T = S->getType(); |
2166 | 3 | assert(T->isVectorTy()); |
2167 | 3 | Value *S2 = IRB.CreateICmpNE(S, getCleanShadow(S)); |
2168 | 3 | return IRB.CreateSExt(S2, T); |
2169 | 3 | } |
2170 | | |
2171 | | // \brief Instrument vector shift instrinsic. |
2172 | | // |
2173 | | // This function instruments intrinsics like int_x86_avx2_psll_w. |
2174 | | // Intrinsic shifts %In by %ShiftSize bits. |
2175 | | // %ShiftSize may be a vector. In that case the lower 64 bits determine shift |
2176 | | // size, and the rest is ignored. Behavior is defined even if shift size is |
2177 | | // greater than register (or field) width. |
2178 | 8 | void handleVectorShiftIntrinsic(IntrinsicInst &I, bool Variable) { |
2179 | 8 | assert(I.getNumArgOperands() == 2); |
2180 | 8 | IRBuilder<> IRB(&I); |
2181 | 8 | // If any of the S2 bits are poisoned, the whole thing is poisoned. |
2182 | 8 | // Otherwise perform the same shift on S1. |
2183 | 8 | Value *S1 = getShadow(&I, 0); |
2184 | 8 | Value *S2 = getShadow(&I, 1); |
2185 | 3 | Value *S2Conv = Variable ? VariableShadowExtend(IRB, S2) |
2186 | 5 | : Lower64ShadowExtend(IRB, S2, getShadowTy(&I)); |
2187 | 8 | Value *V1 = I.getOperand(0); |
2188 | 8 | Value *V2 = I.getOperand(1); |
2189 | 8 | Value *Shift = IRB.CreateCall(I.getCalledValue(), |
2190 | 8 | {IRB.CreateBitCast(S1, V1->getType()), V2}); |
2191 | 8 | Shift = IRB.CreateBitCast(Shift, getShadowTy(&I)); |
2192 | 8 | setShadow(&I, IRB.CreateOr(Shift, S2Conv)); |
2193 | 8 | setOriginForNaryOp(I); |
2194 | 8 | } |
2195 | | |
2196 | | // \brief Get an X86_MMX-sized vector type. |
2197 | 2 | Type *getMMXVectorTy(unsigned EltSizeInBits) { |
2198 | 2 | const unsigned X86_MMXSizeInBits = 64; |
2199 | 2 | return VectorType::get(IntegerType::get(*MS.C, EltSizeInBits), |
2200 | 2 | X86_MMXSizeInBits / EltSizeInBits); |
2201 | 2 | } |
2202 | | |
2203 | | // \brief Returns a signed counterpart for an (un)signed-saturate-and-pack |
2204 | | // intrinsic. |
2205 | 3 | Intrinsic::ID getSignedPackIntrinsic(Intrinsic::ID id) { |
2206 | 3 | switch (id) { |
2207 | 0 | case llvm::Intrinsic::x86_sse2_packsswb_128: |
2208 | 0 | case llvm::Intrinsic::x86_sse2_packuswb_128: |
2209 | 0 | return llvm::Intrinsic::x86_sse2_packsswb_128; |
2210 | 0 |
|
2211 | 1 | case llvm::Intrinsic::x86_sse2_packssdw_128: |
2212 | 1 | case llvm::Intrinsic::x86_sse41_packusdw: |
2213 | 1 | return llvm::Intrinsic::x86_sse2_packssdw_128; |
2214 | 1 | |
2215 | 1 | case llvm::Intrinsic::x86_avx2_packsswb: |
2216 | 1 | case llvm::Intrinsic::x86_avx2_packuswb: |
2217 | 1 | return llvm::Intrinsic::x86_avx2_packsswb; |
2218 | 1 | |
2219 | 0 | case llvm::Intrinsic::x86_avx2_packssdw: |
2220 | 0 | case llvm::Intrinsic::x86_avx2_packusdw: |
2221 | 0 | return llvm::Intrinsic::x86_avx2_packssdw; |
2222 | 0 |
|
2223 | 1 | case llvm::Intrinsic::x86_mmx_packsswb: |
2224 | 1 | case llvm::Intrinsic::x86_mmx_packuswb: |
2225 | 1 | return llvm::Intrinsic::x86_mmx_packsswb; |
2226 | 1 | |
2227 | 0 | case llvm::Intrinsic::x86_mmx_packssdw: |
2228 | 0 | return llvm::Intrinsic::x86_mmx_packssdw; |
2229 | 0 | default: |
2230 | 0 | llvm_unreachable("unexpected intrinsic id"); |
2231 | 0 | } |
2232 | 0 | } |
2233 | | |
2234 | | // \brief Instrument vector pack instrinsic. |
2235 | | // |
2236 | | // This function instruments intrinsics like x86_mmx_packsswb, that |
2237 | | // packs elements of 2 input vectors into half as many bits with saturation. |
2238 | | // Shadow is propagated with the signed variant of the same intrinsic applied |
2239 | | // to sext(Sa != zeroinitializer), sext(Sb != zeroinitializer). |
2240 | | // EltSizeInBits is used only for x86mmx arguments. |
2241 | 3 | void handleVectorPackIntrinsic(IntrinsicInst &I, unsigned EltSizeInBits = 0) { |
2242 | 3 | assert(I.getNumArgOperands() == 2); |
2243 | 3 | bool isX86_MMX = I.getOperand(0)->getType()->isX86_MMXTy(); |
2244 | 3 | IRBuilder<> IRB(&I); |
2245 | 3 | Value *S1 = getShadow(&I, 0); |
2246 | 3 | Value *S2 = getShadow(&I, 1); |
2247 | 3 | assert(isX86_MMX || S1->getType()->isVectorTy()); |
2248 | 3 | |
2249 | 3 | // SExt and ICmpNE below must apply to individual elements of input vectors. |
2250 | 3 | // In case of x86mmx arguments, cast them to appropriate vector types and |
2251 | 3 | // back. |
2252 | 3 | Type *T = isX86_MMX ? getMMXVectorTy(EltSizeInBits)1 : S1->getType()2 ; |
2253 | 3 | if (isX86_MMX3 ) { |
2254 | 1 | S1 = IRB.CreateBitCast(S1, T); |
2255 | 1 | S2 = IRB.CreateBitCast(S2, T); |
2256 | 1 | } |
2257 | 3 | Value *S1_ext = IRB.CreateSExt( |
2258 | 3 | IRB.CreateICmpNE(S1, llvm::Constant::getNullValue(T)), T); |
2259 | 3 | Value *S2_ext = IRB.CreateSExt( |
2260 | 3 | IRB.CreateICmpNE(S2, llvm::Constant::getNullValue(T)), T); |
2261 | 3 | if (isX86_MMX3 ) { |
2262 | 1 | Type *X86_MMXTy = Type::getX86_MMXTy(*MS.C); |
2263 | 1 | S1_ext = IRB.CreateBitCast(S1_ext, X86_MMXTy); |
2264 | 1 | S2_ext = IRB.CreateBitCast(S2_ext, X86_MMXTy); |
2265 | 1 | } |
2266 | 3 | |
2267 | 3 | Function *ShadowFn = Intrinsic::getDeclaration( |
2268 | 3 | F.getParent(), getSignedPackIntrinsic(I.getIntrinsicID())); |
2269 | 3 | |
2270 | 3 | Value *S = |
2271 | 3 | IRB.CreateCall(ShadowFn, {S1_ext, S2_ext}, "_msprop_vector_pack"); |
2272 | 3 | if (isX86_MMX3 ) S = IRB.CreateBitCast(S, getShadowTy(&I))1 ; |
2273 | 3 | setShadow(&I, S); |
2274 | 3 | setOriginForNaryOp(I); |
2275 | 3 | } |
2276 | | |
2277 | | // \brief Instrument sum-of-absolute-differencies intrinsic. |
2278 | 2 | void handleVectorSadIntrinsic(IntrinsicInst &I) { |
2279 | 2 | const unsigned SignificantBitsPerResultElement = 16; |
2280 | 2 | bool isX86_MMX = I.getOperand(0)->getType()->isX86_MMXTy(); |
2281 | 2 | Type *ResTy = isX86_MMX ? IntegerType::get(*MS.C, 64)1 : I.getType()1 ; |
2282 | 2 | unsigned ZeroBitsPerResultElement = |
2283 | 2 | ResTy->getScalarSizeInBits() - SignificantBitsPerResultElement; |
2284 | 2 | |
2285 | 2 | IRBuilder<> IRB(&I); |
2286 | 2 | Value *S = IRB.CreateOr(getShadow(&I, 0), getShadow(&I, 1)); |
2287 | 2 | S = IRB.CreateBitCast(S, ResTy); |
2288 | 2 | S = IRB.CreateSExt(IRB.CreateICmpNE(S, Constant::getNullValue(ResTy)), |
2289 | 2 | ResTy); |
2290 | 2 | S = IRB.CreateLShr(S, ZeroBitsPerResultElement); |
2291 | 2 | S = IRB.CreateBitCast(S, getShadowTy(&I)); |
2292 | 2 | setShadow(&I, S); |
2293 | 2 | setOriginForNaryOp(I); |
2294 | 2 | } |
2295 | | |
2296 | | // \brief Instrument multiply-add intrinsic. |
2297 | | void handleVectorPmaddIntrinsic(IntrinsicInst &I, |
2298 | 2 | unsigned EltSizeInBits = 0) { |
2299 | 2 | bool isX86_MMX = I.getOperand(0)->getType()->isX86_MMXTy(); |
2300 | 2 | Type *ResTy = isX86_MMX ? getMMXVectorTy(EltSizeInBits * 2)1 : I.getType()1 ; |
2301 | 2 | IRBuilder<> IRB(&I); |
2302 | 2 | Value *S = IRB.CreateOr(getShadow(&I, 0), getShadow(&I, 1)); |
2303 | 2 | S = IRB.CreateBitCast(S, ResTy); |
2304 | 2 | S = IRB.CreateSExt(IRB.CreateICmpNE(S, Constant::getNullValue(ResTy)), |
2305 | 2 | ResTy); |
2306 | 2 | S = IRB.CreateBitCast(S, getShadowTy(&I)); |
2307 | 2 | setShadow(&I, S); |
2308 | 2 | setOriginForNaryOp(I); |
2309 | 2 | } |
2310 | | |
2311 | | // \brief Instrument compare-packed intrinsic. |
2312 | | // Basically, an or followed by sext(icmp ne 0) to end up with all-zeros or |
2313 | | // all-ones shadow. |
2314 | 1 | void handleVectorComparePackedIntrinsic(IntrinsicInst &I) { |
2315 | 1 | IRBuilder<> IRB(&I); |
2316 | 1 | Type *ResTy = getShadowTy(&I); |
2317 | 1 | Value *S0 = IRB.CreateOr(getShadow(&I, 0), getShadow(&I, 1)); |
2318 | 1 | Value *S = IRB.CreateSExt( |
2319 | 1 | IRB.CreateICmpNE(S0, Constant::getNullValue(ResTy)), ResTy); |
2320 | 1 | setShadow(&I, S); |
2321 | 1 | setOriginForNaryOp(I); |
2322 | 1 | } |
2323 | | |
2324 | | // \brief Instrument compare-scalar intrinsic. |
2325 | | // This handles both cmp* intrinsics which return the result in the first |
2326 | | // element of a vector, and comi* which return the result as i32. |
2327 | 4 | void handleVectorCompareScalarIntrinsic(IntrinsicInst &I) { |
2328 | 4 | IRBuilder<> IRB(&I); |
2329 | 4 | Value *S0 = IRB.CreateOr(getShadow(&I, 0), getShadow(&I, 1)); |
2330 | 4 | Value *S = LowerElementShadowExtend(IRB, S0, getShadowTy(&I)); |
2331 | 4 | setShadow(&I, S); |
2332 | 4 | setOriginForNaryOp(I); |
2333 | 4 | } |
2334 | | |
2335 | 2 | void handleStmxcsr(IntrinsicInst &I) { |
2336 | 2 | IRBuilder<> IRB(&I); |
2337 | 2 | Value* Addr = I.getArgOperand(0); |
2338 | 2 | Type *Ty = IRB.getInt32Ty(); |
2339 | 2 | Value *ShadowPtr = getShadowPtr(Addr, Ty, IRB); |
2340 | 2 | |
2341 | 2 | IRB.CreateStore(getCleanShadow(Ty), |
2342 | 2 | IRB.CreatePointerCast(ShadowPtr, Ty->getPointerTo())); |
2343 | 2 | |
2344 | 2 | if (ClCheckAccessAddress) |
2345 | 1 | insertShadowCheck(Addr, &I); |
2346 | 2 | } |
2347 | | |
2348 | 2 | void handleLdmxcsr(IntrinsicInst &I) { |
2349 | 2 | if (!InsertChecks2 ) return0 ; |
2350 | 2 | |
2351 | 2 | IRBuilder<> IRB(&I); |
2352 | 2 | Value *Addr = I.getArgOperand(0); |
2353 | 2 | Type *Ty = IRB.getInt32Ty(); |
2354 | 2 | unsigned Alignment = 1; |
2355 | 2 | |
2356 | 2 | if (ClCheckAccessAddress) |
2357 | 1 | insertShadowCheck(Addr, &I); |
2358 | 2 | |
2359 | 2 | Value *Shadow = IRB.CreateAlignedLoad(getShadowPtr(Addr, Ty, IRB), |
2360 | 2 | Alignment, "_ldmxcsr"); |
2361 | 2 | Value *Origin = MS.TrackOrigins |
2362 | 0 | ? IRB.CreateLoad(getOriginPtr(Addr, IRB, Alignment)) |
2363 | 2 | : getCleanOrigin(); |
2364 | 2 | insertShadowCheck(Shadow, Origin, &I); |
2365 | 2 | } |
2366 | | |
2367 | 60 | void visitIntrinsicInst(IntrinsicInst &I) { |
2368 | 60 | switch (I.getIntrinsicID()) { |
2369 | 2 | case llvm::Intrinsic::bswap: |
2370 | 2 | handleBswap(I); |
2371 | 2 | break; |
2372 | 2 | case llvm::Intrinsic::x86_sse_stmxcsr: |
2373 | 2 | handleStmxcsr(I); |
2374 | 2 | break; |
2375 | 2 | case llvm::Intrinsic::x86_sse_ldmxcsr: |
2376 | 2 | handleLdmxcsr(I); |
2377 | 2 | break; |
2378 | 2 | case llvm::Intrinsic::x86_avx512_vcvtsd2usi64: |
2379 | 2 | case llvm::Intrinsic::x86_avx512_vcvtsd2usi32: |
2380 | 2 | case llvm::Intrinsic::x86_avx512_vcvtss2usi64: |
2381 | 2 | case llvm::Intrinsic::x86_avx512_vcvtss2usi32: |
2382 | 2 | case llvm::Intrinsic::x86_avx512_cvttss2usi64: |
2383 | 2 | case llvm::Intrinsic::x86_avx512_cvttss2usi: |
2384 | 2 | case llvm::Intrinsic::x86_avx512_cvttsd2usi64: |
2385 | 2 | case llvm::Intrinsic::x86_avx512_cvttsd2usi: |
2386 | 2 | case llvm::Intrinsic::x86_avx512_cvtusi2sd: |
2387 | 2 | case llvm::Intrinsic::x86_avx512_cvtusi2ss: |
2388 | 2 | case llvm::Intrinsic::x86_avx512_cvtusi642sd: |
2389 | 2 | case llvm::Intrinsic::x86_avx512_cvtusi642ss: |
2390 | 2 | case llvm::Intrinsic::x86_sse2_cvtsd2si64: |
2391 | 2 | case llvm::Intrinsic::x86_sse2_cvtsd2si: |
2392 | 2 | case llvm::Intrinsic::x86_sse2_cvtsd2ss: |
2393 | 2 | case llvm::Intrinsic::x86_sse2_cvtsi2sd: |
2394 | 2 | case llvm::Intrinsic::x86_sse2_cvtsi642sd: |
2395 | 2 | case llvm::Intrinsic::x86_sse2_cvtss2sd: |
2396 | 2 | case llvm::Intrinsic::x86_sse2_cvttsd2si64: |
2397 | 2 | case llvm::Intrinsic::x86_sse2_cvttsd2si: |
2398 | 2 | case llvm::Intrinsic::x86_sse_cvtsi2ss: |
2399 | 2 | case llvm::Intrinsic::x86_sse_cvtsi642ss: |
2400 | 2 | case llvm::Intrinsic::x86_sse_cvtss2si64: |
2401 | 2 | case llvm::Intrinsic::x86_sse_cvtss2si: |
2402 | 2 | case llvm::Intrinsic::x86_sse_cvttss2si64: |
2403 | 2 | case llvm::Intrinsic::x86_sse_cvttss2si: |
2404 | 2 | handleVectorConvertIntrinsic(I, 1); |
2405 | 2 | break; |
2406 | 1 | case llvm::Intrinsic::x86_sse_cvtps2pi: |
2407 | 1 | case llvm::Intrinsic::x86_sse_cvttps2pi: |
2408 | 1 | handleVectorConvertIntrinsic(I, 2); |
2409 | 1 | break; |
2410 | 1 | |
2411 | 5 | case llvm::Intrinsic::x86_avx512_psll_w_512: |
2412 | 5 | case llvm::Intrinsic::x86_avx512_psll_d_512: |
2413 | 5 | case llvm::Intrinsic::x86_avx512_psll_q_512: |
2414 | 5 | case llvm::Intrinsic::x86_avx512_pslli_w_512: |
2415 | 5 | case llvm::Intrinsic::x86_avx512_pslli_d_512: |
2416 | 5 | case llvm::Intrinsic::x86_avx512_pslli_q_512: |
2417 | 5 | case llvm::Intrinsic::x86_avx512_psrl_w_512: |
2418 | 5 | case llvm::Intrinsic::x86_avx512_psrl_d_512: |
2419 | 5 | case llvm::Intrinsic::x86_avx512_psrl_q_512: |
2420 | 5 | case llvm::Intrinsic::x86_avx512_psra_w_512: |
2421 | 5 | case llvm::Intrinsic::x86_avx512_psra_d_512: |
2422 | 5 | case llvm::Intrinsic::x86_avx512_psra_q_512: |
2423 | 5 | case llvm::Intrinsic::x86_avx512_psrli_w_512: |
2424 | 5 | case llvm::Intrinsic::x86_avx512_psrli_d_512: |
2425 | 5 | case llvm::Intrinsic::x86_avx512_psrli_q_512: |
2426 | 5 | case llvm::Intrinsic::x86_avx512_psrai_w_512: |
2427 | 5 | case llvm::Intrinsic::x86_avx512_psrai_d_512: |
2428 | 5 | case llvm::Intrinsic::x86_avx512_psrai_q_512: |
2429 | 5 | case llvm::Intrinsic::x86_avx512_psra_q_256: |
2430 | 5 | case llvm::Intrinsic::x86_avx512_psra_q_128: |
2431 | 5 | case llvm::Intrinsic::x86_avx512_psrai_q_256: |
2432 | 5 | case llvm::Intrinsic::x86_avx512_psrai_q_128: |
2433 | 5 | case llvm::Intrinsic::x86_avx2_psll_w: |
2434 | 5 | case llvm::Intrinsic::x86_avx2_psll_d: |
2435 | 5 | case llvm::Intrinsic::x86_avx2_psll_q: |
2436 | 5 | case llvm::Intrinsic::x86_avx2_pslli_w: |
2437 | 5 | case llvm::Intrinsic::x86_avx2_pslli_d: |
2438 | 5 | case llvm::Intrinsic::x86_avx2_pslli_q: |
2439 | 5 | case llvm::Intrinsic::x86_avx2_psrl_w: |
2440 | 5 | case llvm::Intrinsic::x86_avx2_psrl_d: |
2441 | 5 | case llvm::Intrinsic::x86_avx2_psrl_q: |
2442 | 5 | case llvm::Intrinsic::x86_avx2_psra_w: |
2443 | 5 | case llvm::Intrinsic::x86_avx2_psra_d: |
2444 | 5 | case llvm::Intrinsic::x86_avx2_psrli_w: |
2445 | 5 | case llvm::Intrinsic::x86_avx2_psrli_d: |
2446 | 5 | case llvm::Intrinsic::x86_avx2_psrli_q: |
2447 | 5 | case llvm::Intrinsic::x86_avx2_psrai_w: |
2448 | 5 | case llvm::Intrinsic::x86_avx2_psrai_d: |
2449 | 5 | case llvm::Intrinsic::x86_sse2_psll_w: |
2450 | 5 | case llvm::Intrinsic::x86_sse2_psll_d: |
2451 | 5 | case llvm::Intrinsic::x86_sse2_psll_q: |
2452 | 5 | case llvm::Intrinsic::x86_sse2_pslli_w: |
2453 | 5 | case llvm::Intrinsic::x86_sse2_pslli_d: |
2454 | 5 | case llvm::Intrinsic::x86_sse2_pslli_q: |
2455 | 5 | case llvm::Intrinsic::x86_sse2_psrl_w: |
2456 | 5 | case llvm::Intrinsic::x86_sse2_psrl_d: |
2457 | 5 | case llvm::Intrinsic::x86_sse2_psrl_q: |
2458 | 5 | case llvm::Intrinsic::x86_sse2_psra_w: |
2459 | 5 | case llvm::Intrinsic::x86_sse2_psra_d: |
2460 | 5 | case llvm::Intrinsic::x86_sse2_psrli_w: |
2461 | 5 | case llvm::Intrinsic::x86_sse2_psrli_d: |
2462 | 5 | case llvm::Intrinsic::x86_sse2_psrli_q: |
2463 | 5 | case llvm::Intrinsic::x86_sse2_psrai_w: |
2464 | 5 | case llvm::Intrinsic::x86_sse2_psrai_d: |
2465 | 5 | case llvm::Intrinsic::x86_mmx_psll_w: |
2466 | 5 | case llvm::Intrinsic::x86_mmx_psll_d: |
2467 | 5 | case llvm::Intrinsic::x86_mmx_psll_q: |
2468 | 5 | case llvm::Intrinsic::x86_mmx_pslli_w: |
2469 | 5 | case llvm::Intrinsic::x86_mmx_pslli_d: |
2470 | 5 | case llvm::Intrinsic::x86_mmx_pslli_q: |
2471 | 5 | case llvm::Intrinsic::x86_mmx_psrl_w: |
2472 | 5 | case llvm::Intrinsic::x86_mmx_psrl_d: |
2473 | 5 | case llvm::Intrinsic::x86_mmx_psrl_q: |
2474 | 5 | case llvm::Intrinsic::x86_mmx_psra_w: |
2475 | 5 | case llvm::Intrinsic::x86_mmx_psra_d: |
2476 | 5 | case llvm::Intrinsic::x86_mmx_psrli_w: |
2477 | 5 | case llvm::Intrinsic::x86_mmx_psrli_d: |
2478 | 5 | case llvm::Intrinsic::x86_mmx_psrli_q: |
2479 | 5 | case llvm::Intrinsic::x86_mmx_psrai_w: |
2480 | 5 | case llvm::Intrinsic::x86_mmx_psrai_d: |
2481 | 5 | handleVectorShiftIntrinsic(I, /* Variable */ false); |
2482 | 5 | break; |
2483 | 3 | case llvm::Intrinsic::x86_avx2_psllv_d: |
2484 | 3 | case llvm::Intrinsic::x86_avx2_psllv_d_256: |
2485 | 3 | case llvm::Intrinsic::x86_avx512_psllv_d_512: |
2486 | 3 | case llvm::Intrinsic::x86_avx2_psllv_q: |
2487 | 3 | case llvm::Intrinsic::x86_avx2_psllv_q_256: |
2488 | 3 | case llvm::Intrinsic::x86_avx512_psllv_q_512: |
2489 | 3 | case llvm::Intrinsic::x86_avx2_psrlv_d: |
2490 | 3 | case llvm::Intrinsic::x86_avx2_psrlv_d_256: |
2491 | 3 | case llvm::Intrinsic::x86_avx512_psrlv_d_512: |
2492 | 3 | case llvm::Intrinsic::x86_avx2_psrlv_q: |
2493 | 3 | case llvm::Intrinsic::x86_avx2_psrlv_q_256: |
2494 | 3 | case llvm::Intrinsic::x86_avx512_psrlv_q_512: |
2495 | 3 | case llvm::Intrinsic::x86_avx2_psrav_d: |
2496 | 3 | case llvm::Intrinsic::x86_avx2_psrav_d_256: |
2497 | 3 | case llvm::Intrinsic::x86_avx512_psrav_d_512: |
2498 | 3 | case llvm::Intrinsic::x86_avx512_psrav_q_128: |
2499 | 3 | case llvm::Intrinsic::x86_avx512_psrav_q_256: |
2500 | 3 | case llvm::Intrinsic::x86_avx512_psrav_q_512: |
2501 | 3 | handleVectorShiftIntrinsic(I, /* Variable */ true); |
2502 | 3 | break; |
2503 | 3 | |
2504 | 2 | case llvm::Intrinsic::x86_sse2_packsswb_128: |
2505 | 2 | case llvm::Intrinsic::x86_sse2_packssdw_128: |
2506 | 2 | case llvm::Intrinsic::x86_sse2_packuswb_128: |
2507 | 2 | case llvm::Intrinsic::x86_sse41_packusdw: |
2508 | 2 | case llvm::Intrinsic::x86_avx2_packsswb: |
2509 | 2 | case llvm::Intrinsic::x86_avx2_packssdw: |
2510 | 2 | case llvm::Intrinsic::x86_avx2_packuswb: |
2511 | 2 | case llvm::Intrinsic::x86_avx2_packusdw: |
2512 | 2 | handleVectorPackIntrinsic(I); |
2513 | 2 | break; |
2514 | 2 | |
2515 | 1 | case llvm::Intrinsic::x86_mmx_packsswb: |
2516 | 1 | case llvm::Intrinsic::x86_mmx_packuswb: |
2517 | 1 | handleVectorPackIntrinsic(I, 16); |
2518 | 1 | break; |
2519 | 1 | |
2520 | 0 | case llvm::Intrinsic::x86_mmx_packssdw: |
2521 | 0 | handleVectorPackIntrinsic(I, 32); |
2522 | 0 | break; |
2523 | 1 | |
2524 | 2 | case llvm::Intrinsic::x86_mmx_psad_bw: |
2525 | 2 | case llvm::Intrinsic::x86_sse2_psad_bw: |
2526 | 2 | case llvm::Intrinsic::x86_avx2_psad_bw: |
2527 | 2 | handleVectorSadIntrinsic(I); |
2528 | 2 | break; |
2529 | 2 | |
2530 | 1 | case llvm::Intrinsic::x86_sse2_pmadd_wd: |
2531 | 1 | case llvm::Intrinsic::x86_avx2_pmadd_wd: |
2532 | 1 | case llvm::Intrinsic::x86_ssse3_pmadd_ub_sw_128: |
2533 | 1 | case llvm::Intrinsic::x86_avx2_pmadd_ub_sw: |
2534 | 1 | handleVectorPmaddIntrinsic(I); |
2535 | 1 | break; |
2536 | 1 | |
2537 | 1 | case llvm::Intrinsic::x86_ssse3_pmadd_ub_sw: |
2538 | 1 | handleVectorPmaddIntrinsic(I, 8); |
2539 | 1 | break; |
2540 | 1 | |
2541 | 0 | case llvm::Intrinsic::x86_mmx_pmadd_wd: |
2542 | 0 | handleVectorPmaddIntrinsic(I, 16); |
2543 | 0 | break; |
2544 | 1 | |
2545 | 4 | case llvm::Intrinsic::x86_sse_cmp_ss: |
2546 | 4 | case llvm::Intrinsic::x86_sse2_cmp_sd: |
2547 | 4 | case llvm::Intrinsic::x86_sse_comieq_ss: |
2548 | 4 | case llvm::Intrinsic::x86_sse_comilt_ss: |
2549 | 4 | case llvm::Intrinsic::x86_sse_comile_ss: |
2550 | 4 | case llvm::Intrinsic::x86_sse_comigt_ss: |
2551 | 4 | case llvm::Intrinsic::x86_sse_comige_ss: |
2552 | 4 | case llvm::Intrinsic::x86_sse_comineq_ss: |
2553 | 4 | case llvm::Intrinsic::x86_sse_ucomieq_ss: |
2554 | 4 | case llvm::Intrinsic::x86_sse_ucomilt_ss: |
2555 | 4 | case llvm::Intrinsic::x86_sse_ucomile_ss: |
2556 | 4 | case llvm::Intrinsic::x86_sse_ucomigt_ss: |
2557 | 4 | case llvm::Intrinsic::x86_sse_ucomige_ss: |
2558 | 4 | case llvm::Intrinsic::x86_sse_ucomineq_ss: |
2559 | 4 | case llvm::Intrinsic::x86_sse2_comieq_sd: |
2560 | 4 | case llvm::Intrinsic::x86_sse2_comilt_sd: |
2561 | 4 | case llvm::Intrinsic::x86_sse2_comile_sd: |
2562 | 4 | case llvm::Intrinsic::x86_sse2_comigt_sd: |
2563 | 4 | case llvm::Intrinsic::x86_sse2_comige_sd: |
2564 | 4 | case llvm::Intrinsic::x86_sse2_comineq_sd: |
2565 | 4 | case llvm::Intrinsic::x86_sse2_ucomieq_sd: |
2566 | 4 | case llvm::Intrinsic::x86_sse2_ucomilt_sd: |
2567 | 4 | case llvm::Intrinsic::x86_sse2_ucomile_sd: |
2568 | 4 | case llvm::Intrinsic::x86_sse2_ucomigt_sd: |
2569 | 4 | case llvm::Intrinsic::x86_sse2_ucomige_sd: |
2570 | 4 | case llvm::Intrinsic::x86_sse2_ucomineq_sd: |
2571 | 4 | handleVectorCompareScalarIntrinsic(I); |
2572 | 4 | break; |
2573 | 4 | |
2574 | 1 | case llvm::Intrinsic::x86_sse_cmp_ps: |
2575 | 1 | case llvm::Intrinsic::x86_sse2_cmp_pd: |
2576 | 1 | // FIXME: For x86_avx_cmp_pd_256 and x86_avx_cmp_ps_256 this function |
2577 | 1 | // generates reasonably looking IR that fails in the backend with "Do not |
2578 | 1 | // know how to split the result of this operator!". |
2579 | 1 | handleVectorComparePackedIntrinsic(I); |
2580 | 1 | break; |
2581 | 1 | |
2582 | 31 | default: |
2583 | 31 | if (!handleUnknownIntrinsic(I)) |
2584 | 27 | visitInstruction(I); |
2585 | 2 | break; |
2586 | 60 | } |
2587 | 60 | } |
2588 | | |
2589 | 165 | void visitCallSite(CallSite CS) { |
2590 | 165 | Instruction &I = *CS.getInstruction(); |
2591 | 165 | if (I.getMetadata("nosanitize")165 ) return36 ; |
2592 | 165 | assert((CS.isCall() || CS.isInvoke()) && "Unknown type of CallSite"); |
2593 | 129 | if (CS.isCall()129 ) { |
2594 | 129 | CallInst *Call = cast<CallInst>(&I); |
2595 | 129 | |
2596 | 129 | // For inline asm, do the usual thing: check argument shadow and mark all |
2597 | 129 | // outputs as clean. Note that any side effects of the inline asm that are |
2598 | 129 | // not immediately visible in its constraints are not handled. |
2599 | 129 | if (Call->isInlineAsm()129 ) { |
2600 | 0 | visitInstruction(I); |
2601 | 0 | return; |
2602 | 0 | } |
2603 | 129 | |
2604 | 129 | assert(!isa<IntrinsicInst>(&I) && "intrinsics are handled elsewhere"); |
2605 | 129 | |
2606 | 129 | // We are going to insert code that relies on the fact that the callee |
2607 | 129 | // will become a non-readonly function after it is instrumented by us. To |
2608 | 129 | // prevent this code from being optimized out, mark that function |
2609 | 129 | // non-readonly in advance. |
2610 | 129 | if (Function *Func129 = Call->getCalledFunction()) { |
2611 | 129 | // Clear out readonly/readnone attributes. |
2612 | 129 | AttrBuilder B; |
2613 | 129 | B.addAttribute(Attribute::ReadOnly) |
2614 | 129 | .addAttribute(Attribute::ReadNone); |
2615 | 129 | Func->removeAttributes(AttributeList::FunctionIndex, B); |
2616 | 129 | } |
2617 | 129 | |
2618 | 129 | maybeMarkSanitizerLibraryCallNoBuiltin(Call, TLI); |
2619 | 129 | } |
2620 | 129 | IRBuilder<> IRB(&I); |
2621 | 129 | |
2622 | 129 | unsigned ArgOffset = 0; |
2623 | 129 | DEBUG(dbgs() << " CallSite: " << I << "\n"); |
2624 | 129 | for (CallSite::arg_iterator ArgIt = CS.arg_begin(), End = CS.arg_end(); |
2625 | 321 | ArgIt != End321 ; ++ArgIt192 ) { |
2626 | 192 | Value *A = *ArgIt; |
2627 | 192 | unsigned i = ArgIt - CS.arg_begin(); |
2628 | 192 | if (!A->getType()->isSized()192 ) { |
2629 | 0 | DEBUG(dbgs() << "Arg " << i << " is not sized: " << I << "\n"); |
2630 | 0 | continue; |
2631 | 0 | } |
2632 | 192 | unsigned Size = 0; |
2633 | 192 | Value *Store = nullptr; |
2634 | 192 | // Compute the Shadow for arg even if it is ByVal, because |
2635 | 192 | // in that case getShadow() will copy the actual arg shadow to |
2636 | 192 | // __msan_param_tls. |
2637 | 192 | Value *ArgShadow = getShadow(A); |
2638 | 192 | Value *ArgShadowBase = getShadowPtrForArgument(A, IRB, ArgOffset); |
2639 | 192 | DEBUG(dbgs() << " Arg#" << i << ": " << *A << |
2640 | 192 | " Shadow: " << *ArgShadow << "\n"); |
2641 | 192 | bool ArgIsInitialized = false; |
2642 | 192 | const DataLayout &DL = F.getParent()->getDataLayout(); |
2643 | 192 | if (CS.paramHasAttr(i, Attribute::ByVal)192 ) { |
2644 | 7 | assert(A->getType()->isPointerTy() && |
2645 | 7 | "ByVal argument is not a pointer!"); |
2646 | 7 | Size = DL.getTypeAllocSize(A->getType()->getPointerElementType()); |
2647 | 7 | if (ArgOffset + Size > kParamTLSSize7 ) break0 ; |
2648 | 7 | unsigned ParamAlignment = CS.getParamAlignment(i); |
2649 | 7 | unsigned Alignment = std::min(ParamAlignment, kShadowTLSAlignment); |
2650 | 7 | Store = IRB.CreateMemCpy(ArgShadowBase, |
2651 | 7 | getShadowPtr(A, Type::getInt8Ty(*MS.C), IRB), |
2652 | 7 | Size, Alignment); |
2653 | 192 | } else { |
2654 | 185 | Size = DL.getTypeAllocSize(A->getType()); |
2655 | 185 | if (ArgOffset + Size > kParamTLSSize185 ) break0 ; |
2656 | 185 | Store = IRB.CreateAlignedStore(ArgShadow, ArgShadowBase, |
2657 | 185 | kShadowTLSAlignment); |
2658 | 185 | Constant *Cst = dyn_cast<Constant>(ArgShadow); |
2659 | 185 | if (Cst && 185 Cst->isNullValue()104 ) ArgIsInitialized = true102 ; |
2660 | 185 | } |
2661 | 192 | if (192 MS.TrackOrigins && 192 !ArgIsInitialized12 ) |
2662 | 9 | IRB.CreateStore(getOrigin(A), |
2663 | 9 | getOriginPtrForArgument(A, IRB, ArgOffset)); |
2664 | 192 | (void)Store; |
2665 | 192 | assert(Size != 0 && Store != nullptr); |
2666 | 192 | DEBUG(dbgs() << " Param:" << *Store << "\n"); |
2667 | 192 | ArgOffset += alignTo(Size, 8); |
2668 | 192 | } |
2669 | 129 | DEBUG(dbgs() << " done with call args\n"); |
2670 | 129 | |
2671 | 129 | FunctionType *FT = |
2672 | 129 | cast<FunctionType>(CS.getCalledValue()->getType()->getContainedType(0)); |
2673 | 129 | if (FT->isVarArg()129 ) { |
2674 | 25 | VAHelper->visitCallSite(CS, IRB); |
2675 | 25 | } |
2676 | 129 | |
2677 | 129 | // Now, get the shadow for the RetVal. |
2678 | 129 | if (!I.getType()->isSized()129 ) return79 ; |
2679 | 50 | // Don't emit the epilogue for musttail call returns. |
2680 | 50 | if (50 CS.isCall() && 50 cast<CallInst>(&I)->isMustTailCall()50 ) return4 ; |
2681 | 46 | IRBuilder<> IRBBefore(&I); |
2682 | 46 | // Until we have full dynamic coverage, make sure the retval shadow is 0. |
2683 | 46 | Value *Base = getShadowPtrForRetval(&I, IRBBefore); |
2684 | 46 | IRBBefore.CreateAlignedStore(getCleanShadow(&I), Base, kShadowTLSAlignment); |
2685 | 46 | BasicBlock::iterator NextInsn; |
2686 | 46 | if (CS.isCall()46 ) { |
2687 | 46 | NextInsn = ++I.getIterator(); |
2688 | 46 | assert(NextInsn != I.getParent()->end()); |
2689 | 46 | } else { |
2690 | 0 | BasicBlock *NormalDest = cast<InvokeInst>(&I)->getNormalDest(); |
2691 | 0 | if (!NormalDest->getSinglePredecessor()0 ) { |
2692 | 0 | // FIXME: this case is tricky, so we are just conservative here. |
2693 | 0 | // Perhaps we need to split the edge between this BB and NormalDest, |
2694 | 0 | // but a naive attempt to use SplitEdge leads to a crash. |
2695 | 0 | setShadow(&I, getCleanShadow(&I)); |
2696 | 0 | setOrigin(&I, getCleanOrigin()); |
2697 | 0 | return; |
2698 | 0 | } |
2699 | 0 | NextInsn = NormalDest->getFirstInsertionPt(); |
2700 | 0 | assert(NextInsn != NormalDest->end() && |
2701 | 0 | "Could not find insertion point for retval shadow load"); |
2702 | 0 | } |
2703 | 46 | IRBuilder<> IRBAfter(&*NextInsn); |
2704 | 46 | Value *RetvalShadow = |
2705 | 46 | IRBAfter.CreateAlignedLoad(getShadowPtrForRetval(&I, IRBAfter), |
2706 | 46 | kShadowTLSAlignment, "_msret"); |
2707 | 46 | setShadow(&I, RetvalShadow); |
2708 | 46 | if (MS.TrackOrigins) |
2709 | 5 | setOrigin(&I, IRBAfter.CreateLoad(getOriginPtrForRetval(IRBAfter))); |
2710 | 165 | } |
2711 | | |
2712 | 195 | bool isAMustTailRetVal(Value *RetVal) { |
2713 | 195 | if (auto *I195 = dyn_cast<BitCastInst>(RetVal)) { |
2714 | 2 | RetVal = I->getOperand(0); |
2715 | 2 | } |
2716 | 195 | if (auto *I195 = dyn_cast<CallInst>(RetVal)) { |
2717 | 57 | return I->isMustTailCall(); |
2718 | 57 | } |
2719 | 138 | return false; |
2720 | 138 | } |
2721 | | |
2722 | 373 | void visitReturnInst(ReturnInst &I) { |
2723 | 373 | IRBuilder<> IRB(&I); |
2724 | 373 | Value *RetVal = I.getReturnValue(); |
2725 | 373 | if (!RetVal373 ) return178 ; |
2726 | 195 | // Don't emit the epilogue for musttail call returns. |
2727 | 195 | if (195 isAMustTailRetVal(RetVal)195 ) return4 ; |
2728 | 191 | Value *ShadowPtr = getShadowPtrForRetval(RetVal, IRB); |
2729 | 191 | if (CheckReturnValue191 ) { |
2730 | 3 | insertShadowCheck(RetVal, &I); |
2731 | 3 | Value *Shadow = getCleanShadow(RetVal); |
2732 | 3 | IRB.CreateAlignedStore(Shadow, ShadowPtr, kShadowTLSAlignment); |
2733 | 191 | } else { |
2734 | 188 | Value *Shadow = getShadow(RetVal); |
2735 | 188 | IRB.CreateAlignedStore(Shadow, ShadowPtr, kShadowTLSAlignment); |
2736 | 188 | if (MS.TrackOrigins) |
2737 | 60 | IRB.CreateStore(getOrigin(RetVal), getOriginPtrForRetval(IRB)); |
2738 | 188 | } |
2739 | 373 | } |
2740 | | |
2741 | 4 | void visitPHINode(PHINode &I) { |
2742 | 4 | IRBuilder<> IRB(&I); |
2743 | 4 | if (!PropagateShadow4 ) { |
2744 | 2 | setShadow(&I, getCleanShadow(&I)); |
2745 | 2 | setOrigin(&I, getCleanOrigin()); |
2746 | 2 | return; |
2747 | 2 | } |
2748 | 2 | |
2749 | 2 | ShadowPHINodes.push_back(&I); |
2750 | 2 | setShadow(&I, IRB.CreatePHI(getShadowTy(&I), I.getNumIncomingValues(), |
2751 | 2 | "_msphi_s")); |
2752 | 2 | if (MS.TrackOrigins) |
2753 | 1 | setOrigin(&I, IRB.CreatePHI(MS.OriginTy, I.getNumIncomingValues(), |
2754 | 1 | "_msphi_o")); |
2755 | 4 | } |
2756 | | |
2757 | 78 | void visitAllocaInst(AllocaInst &I) { |
2758 | 78 | setShadow(&I, getCleanShadow(&I)); |
2759 | 78 | setOrigin(&I, getCleanOrigin()); |
2760 | 78 | IRBuilder<> IRB(I.getNextNode()); |
2761 | 78 | const DataLayout &DL = F.getParent()->getDataLayout(); |
2762 | 78 | uint64_t TypeSize = DL.getTypeAllocSize(I.getAllocatedType()); |
2763 | 78 | Value *Len = ConstantInt::get(MS.IntptrTy, TypeSize); |
2764 | 78 | if (I.isArrayAllocation()) |
2765 | 8 | Len = IRB.CreateMul(Len, I.getArraySize()); |
2766 | 78 | if (PoisonStack && 78 ClPoisonStackWithCall68 ) { |
2767 | 4 | IRB.CreateCall(MS.MsanPoisonStackFn, |
2768 | 4 | {IRB.CreatePointerCast(&I, IRB.getInt8PtrTy()), Len}); |
2769 | 78 | } else { |
2770 | 74 | Value *ShadowBase = getShadowPtr(&I, Type::getInt8PtrTy(*MS.C), IRB); |
2771 | 74 | Value *PoisonValue = IRB.getInt8(PoisonStack ? ClPoisonStackPattern64 : 010 ); |
2772 | 74 | IRB.CreateMemSet(ShadowBase, PoisonValue, Len, I.getAlignment()); |
2773 | 74 | } |
2774 | 78 | |
2775 | 78 | if (PoisonStack && 78 MS.TrackOrigins68 ) { |
2776 | 13 | SmallString<2048> StackDescriptionStorage; |
2777 | 13 | raw_svector_ostream StackDescription(StackDescriptionStorage); |
2778 | 13 | // We create a string with a description of the stack allocation and |
2779 | 13 | // pass it into __msan_set_alloca_origin. |
2780 | 13 | // It will be printed by the run-time if stack-originated UMR is found. |
2781 | 13 | // The first 4 bytes of the string are set to '----' and will be replaced |
2782 | 13 | // by __msan_va_arg_overflow_size_tls at the first call. |
2783 | 13 | StackDescription << "----" << I.getName() << "@" << F.getName(); |
2784 | 13 | Value *Descr = |
2785 | 13 | createPrivateNonConstGlobalForString(*F.getParent(), |
2786 | 13 | StackDescription.str()); |
2787 | 13 | |
2788 | 13 | IRB.CreateCall(MS.MsanSetAllocaOrigin4Fn, |
2789 | 13 | {IRB.CreatePointerCast(&I, IRB.getInt8PtrTy()), Len, |
2790 | 13 | IRB.CreatePointerCast(Descr, IRB.getInt8PtrTy()), |
2791 | 13 | IRB.CreatePointerCast(&F, MS.IntptrTy)}); |
2792 | 13 | } |
2793 | 78 | } |
2794 | | |
2795 | 11 | void visitSelectInst(SelectInst& I) { |
2796 | 11 | IRBuilder<> IRB(&I); |
2797 | 11 | // a = select b, c, d |
2798 | 11 | Value *B = I.getCondition(); |
2799 | 11 | Value *C = I.getTrueValue(); |
2800 | 11 | Value *D = I.getFalseValue(); |
2801 | 11 | Value *Sb = getShadow(B); |
2802 | 11 | Value *Sc = getShadow(C); |
2803 | 11 | Value *Sd = getShadow(D); |
2804 | 11 | |
2805 | 11 | // Result shadow if condition shadow is 0. |
2806 | 11 | Value *Sa0 = IRB.CreateSelect(B, Sc, Sd); |
2807 | 11 | Value *Sa1; |
2808 | 11 | if (I.getType()->isAggregateType()11 ) { |
2809 | 4 | // To avoid "sign extending" i1 to an arbitrary aggregate type, we just do |
2810 | 4 | // an extra "select". This results in much more compact IR. |
2811 | 4 | // Sa = select Sb, poisoned, (select b, Sc, Sd) |
2812 | 4 | Sa1 = getPoisonedShadow(getShadowTy(I.getType())); |
2813 | 11 | } else { |
2814 | 7 | // Sa = select Sb, [ (c^d) | Sc | Sd ], [ b ? Sc : Sd ] |
2815 | 7 | // If Sb (condition is poisoned), look for bits in c and d that are equal |
2816 | 7 | // and both unpoisoned. |
2817 | 7 | // If !Sb (condition is unpoisoned), simply pick one of Sc and Sd. |
2818 | 7 | |
2819 | 7 | // Cast arguments to shadow-compatible type. |
2820 | 7 | C = CreateAppToShadowCast(IRB, C); |
2821 | 7 | D = CreateAppToShadowCast(IRB, D); |
2822 | 7 | |
2823 | 7 | // Result shadow if condition shadow is 1. |
2824 | 7 | Sa1 = IRB.CreateOr(IRB.CreateXor(C, D), IRB.CreateOr(Sc, Sd)); |
2825 | 7 | } |
2826 | 11 | Value *Sa = IRB.CreateSelect(Sb, Sa1, Sa0, "_msprop_select"); |
2827 | 11 | setShadow(&I, Sa); |
2828 | 11 | if (MS.TrackOrigins11 ) { |
2829 | 6 | // Origins are always i32, so any vector conditions must be flattened. |
2830 | 6 | // FIXME: consider tracking vector origins for app vectors? |
2831 | 6 | if (B->getType()->isVectorTy()6 ) { |
2832 | 1 | Type *FlatTy = getShadowTyNoVec(B->getType()); |
2833 | 1 | B = IRB.CreateICmpNE(IRB.CreateBitCast(B, FlatTy), |
2834 | 1 | ConstantInt::getNullValue(FlatTy)); |
2835 | 1 | Sb = IRB.CreateICmpNE(IRB.CreateBitCast(Sb, FlatTy), |
2836 | 1 | ConstantInt::getNullValue(FlatTy)); |
2837 | 1 | } |
2838 | 6 | // a = select b, c, d |
2839 | 6 | // Oa = Sb ? Ob : (b ? Oc : Od) |
2840 | 6 | setOrigin( |
2841 | 6 | &I, IRB.CreateSelect(Sb, getOrigin(I.getCondition()), |
2842 | 6 | IRB.CreateSelect(B, getOrigin(I.getTrueValue()), |
2843 | 6 | getOrigin(I.getFalseValue())))); |
2844 | 6 | } |
2845 | 11 | } |
2846 | | |
2847 | 0 | void visitLandingPadInst(LandingPadInst &I) { |
2848 | 0 | // Do nothing. |
2849 | 0 | // See http://code.google.com/p/memory-sanitizer/issues/detail?id=1 |
2850 | 0 | setShadow(&I, getCleanShadow(&I)); |
2851 | 0 | setOrigin(&I, getCleanOrigin()); |
2852 | 0 | } |
2853 | | |
2854 | 0 | void visitCatchSwitchInst(CatchSwitchInst &I) { |
2855 | 0 | setShadow(&I, getCleanShadow(&I)); |
2856 | 0 | setOrigin(&I, getCleanOrigin()); |
2857 | 0 | } |
2858 | | |
2859 | 0 | void visitFuncletPadInst(FuncletPadInst &I) { |
2860 | 0 | setShadow(&I, getCleanShadow(&I)); |
2861 | 0 | setOrigin(&I, getCleanOrigin()); |
2862 | 0 | } |
2863 | | |
2864 | 72 | void visitGetElementPtrInst(GetElementPtrInst &I) { |
2865 | 72 | handleShadowOr(I); |
2866 | 72 | } |
2867 | | |
2868 | 14 | void visitExtractValueInst(ExtractValueInst &I) { |
2869 | 14 | IRBuilder<> IRB(&I); |
2870 | 14 | Value *Agg = I.getAggregateOperand(); |
2871 | 14 | DEBUG(dbgs() << "ExtractValue: " << I << "\n"); |
2872 | 14 | Value *AggShadow = getShadow(Agg); |
2873 | 14 | DEBUG(dbgs() << " AggShadow: " << *AggShadow << "\n"); |
2874 | 14 | Value *ResShadow = IRB.CreateExtractValue(AggShadow, I.getIndices()); |
2875 | 14 | DEBUG(dbgs() << " ResShadow: " << *ResShadow << "\n"); |
2876 | 14 | setShadow(&I, ResShadow); |
2877 | 14 | setOriginForNaryOp(I); |
2878 | 14 | } |
2879 | | |
2880 | 12 | void visitInsertValueInst(InsertValueInst &I) { |
2881 | 12 | IRBuilder<> IRB(&I); |
2882 | 12 | DEBUG(dbgs() << "InsertValue: " << I << "\n"); |
2883 | 12 | Value *AggShadow = getShadow(I.getAggregateOperand()); |
2884 | 12 | Value *InsShadow = getShadow(I.getInsertedValueOperand()); |
2885 | 12 | DEBUG(dbgs() << " AggShadow: " << *AggShadow << "\n"); |
2886 | 12 | DEBUG(dbgs() << " InsShadow: " << *InsShadow << "\n"); |
2887 | 12 | Value *Res = IRB.CreateInsertValue(AggShadow, InsShadow, I.getIndices()); |
2888 | 12 | DEBUG(dbgs() << " Res: " << *Res << "\n"); |
2889 | 12 | setShadow(&I, Res); |
2890 | 12 | setOriginForNaryOp(I); |
2891 | 12 | } |
2892 | | |
2893 | 0 | void dumpInst(Instruction &I) { |
2894 | 0 | if (CallInst *CI0 = dyn_cast<CallInst>(&I)) { |
2895 | 0 | errs() << "ZZZ call " << CI->getCalledFunction()->getName() << "\n"; |
2896 | 0 | } else { |
2897 | 0 | errs() << "ZZZ " << I.getOpcodeName() << "\n"; |
2898 | 0 | } |
2899 | 0 | errs() << "QQQ " << I << "\n"; |
2900 | 0 | } |
2901 | | |
2902 | 0 | void visitResumeInst(ResumeInst &I) { |
2903 | 0 | DEBUG(dbgs() << "Resume: " << I << "\n"); |
2904 | 0 | // Nothing to do here. |
2905 | 0 | } |
2906 | | |
2907 | 0 | void visitCleanupReturnInst(CleanupReturnInst &CRI) { |
2908 | 0 | DEBUG(dbgs() << "CleanupReturn: " << CRI << "\n"); |
2909 | 0 | // Nothing to do here. |
2910 | 0 | } |
2911 | | |
2912 | 0 | void visitCatchReturnInst(CatchReturnInst &CRI) { |
2913 | 0 | DEBUG(dbgs() << "CatchReturn: " << CRI << "\n"); |
2914 | 0 | // Nothing to do here. |
2915 | 0 | } |
2916 | | |
2917 | 58 | void visitInstruction(Instruction &I) { |
2918 | 58 | // Everything else: stop propagating and check for poisoned shadow. |
2919 | 58 | if (ClDumpStrictInstructions) |
2920 | 0 | dumpInst(I); |
2921 | 58 | DEBUG(dbgs() << "DEFAULT: " << I << "\n"); |
2922 | 204 | for (size_t i = 0, n = I.getNumOperands(); i < n204 ; i++146 ) { |
2923 | 146 | Value *Operand = I.getOperand(i); |
2924 | 146 | if (Operand->getType()->isSized()) |
2925 | 91 | insertShadowCheck(Operand, &I); |
2926 | 146 | } |
2927 | 58 | setShadow(&I, getCleanShadow(&I)); |
2928 | 58 | setOrigin(&I, getCleanOrigin()); |
2929 | 58 | } |
2930 | | }; |
2931 | | |
2932 | | /// \brief AMD64-specific implementation of VarArgHelper. |
2933 | | struct VarArgAMD64Helper : public VarArgHelper { |
2934 | | // An unfortunate workaround for asymmetric lowering of va_arg stuff. |
2935 | | // See a comment in visitCallSite for more details. |
2936 | | static const unsigned AMD64GpEndOffset = 48; // AMD64 ABI Draft 0.99.6 p3.5.7 |
2937 | | static const unsigned AMD64FpEndOffset = 176; |
2938 | | |
2939 | | Function &F; |
2940 | | MemorySanitizer &MS; |
2941 | | MemorySanitizerVisitor &MSV; |
2942 | | Value *VAArgTLSCopy; |
2943 | | Value *VAArgOverflowSize; |
2944 | | |
2945 | | SmallVector<CallInst*, 16> VAStartInstrumentationList; |
2946 | | |
2947 | | VarArgAMD64Helper(Function &F, MemorySanitizer &MS, |
2948 | | MemorySanitizerVisitor &MSV) |
2949 | | : F(F), MS(MS), MSV(MSV), VAArgTLSCopy(nullptr), |
2950 | 344 | VAArgOverflowSize(nullptr) {} |
2951 | | |
2952 | | enum ArgKind { AK_GeneralPurpose, AK_FloatingPoint, AK_Memory }; |
2953 | | |
2954 | 10 | ArgKind classifyArgument(Value* arg) { |
2955 | 10 | // A very rough approximation of X86_64 argument classification rules. |
2956 | 10 | Type *T = arg->getType(); |
2957 | 10 | if (T->isFPOrFPVectorTy() || 10 T->isX86_MMXTy()10 ) |
2958 | 0 | return AK_FloatingPoint; |
2959 | 10 | if (10 T->isIntegerTy() && 10 T->getPrimitiveSizeInBits() <= 6410 ) |
2960 | 10 | return AK_GeneralPurpose; |
2961 | 0 | if (0 T->isPointerTy()0 ) |
2962 | 0 | return AK_GeneralPurpose; |
2963 | 0 | return AK_Memory; |
2964 | 0 | } |
2965 | | |
2966 | | // For VarArg functions, store the argument shadow in an ABI-specific format |
2967 | | // that corresponds to va_list layout. |
2968 | | // We do this because Clang lowers va_arg in the frontend, and this pass |
2969 | | // only sees the low level code that deals with va_list internals. |
2970 | | // A much easier alternative (provided that Clang emits va_arg instructions) |
2971 | | // would have been to associate each live instance of va_list with a copy of |
2972 | | // MSanParamTLS, and extract shadow on va_arg() call in the argument list |
2973 | | // order. |
2974 | 7 | void visitCallSite(CallSite &CS, IRBuilder<> &IRB) override { |
2975 | 7 | unsigned GpOffset = 0; |
2976 | 7 | unsigned FpOffset = AMD64GpEndOffset; |
2977 | 7 | unsigned OverflowOffset = AMD64FpEndOffset; |
2978 | 7 | const DataLayout &DL = F.getParent()->getDataLayout(); |
2979 | 7 | for (CallSite::arg_iterator ArgIt = CS.arg_begin(), End = CS.arg_end(); |
2980 | 19 | ArgIt != End19 ; ++ArgIt12 ) { |
2981 | 12 | Value *A = *ArgIt; |
2982 | 12 | unsigned ArgNo = CS.getArgumentNo(ArgIt); |
2983 | 12 | bool IsFixed = ArgNo < CS.getFunctionType()->getNumParams(); |
2984 | 12 | bool IsByVal = CS.paramHasAttr(ArgNo, Attribute::ByVal); |
2985 | 12 | if (IsByVal12 ) { |
2986 | 2 | // ByVal arguments always go to the overflow area. |
2987 | 2 | // Fixed arguments passed through the overflow area will be stepped |
2988 | 2 | // over by va_start, so don't count them towards the offset. |
2989 | 2 | if (IsFixed) |
2990 | 0 | continue; |
2991 | 2 | assert(A->getType()->isPointerTy()); |
2992 | 2 | Type *RealTy = A->getType()->getPointerElementType(); |
2993 | 2 | uint64_t ArgSize = DL.getTypeAllocSize(RealTy); |
2994 | 2 | Value *Base = getShadowPtrForVAArgument(RealTy, IRB, OverflowOffset); |
2995 | 2 | OverflowOffset += alignTo(ArgSize, 8); |
2996 | 2 | IRB.CreateMemCpy(Base, MSV.getShadowPtr(A, IRB.getInt8Ty(), IRB), |
2997 | 2 | ArgSize, kShadowTLSAlignment); |
2998 | 12 | } else { |
2999 | 10 | ArgKind AK = classifyArgument(A); |
3000 | 10 | if (AK == AK_GeneralPurpose && 10 GpOffset >= AMD64GpEndOffset10 ) |
3001 | 0 | AK = AK_Memory; |
3002 | 10 | if (AK == AK_FloatingPoint && 10 FpOffset >= AMD64FpEndOffset0 ) |
3003 | 0 | AK = AK_Memory; |
3004 | 10 | Value *Base; |
3005 | 10 | switch (AK) { |
3006 | 10 | case AK_GeneralPurpose: |
3007 | 10 | Base = getShadowPtrForVAArgument(A->getType(), IRB, GpOffset); |
3008 | 10 | GpOffset += 8; |
3009 | 10 | break; |
3010 | 0 | case AK_FloatingPoint: |
3011 | 0 | Base = getShadowPtrForVAArgument(A->getType(), IRB, FpOffset); |
3012 | 0 | FpOffset += 16; |
3013 | 0 | break; |
3014 | 0 | case AK_Memory: |
3015 | 0 | if (IsFixed) |
3016 | 0 | continue; |
3017 | 0 | uint64_t ArgSize = DL.getTypeAllocSize(A->getType()); |
3018 | 0 | Base = getShadowPtrForVAArgument(A->getType(), IRB, OverflowOffset); |
3019 | 0 | OverflowOffset += alignTo(ArgSize, 8); |
3020 | 10 | } |
3021 | 10 | // Take fixed arguments into account for GpOffset and FpOffset, |
3022 | 10 | // but don't actually store shadows for them. |
3023 | 10 | if (10 IsFixed10 ) |
3024 | 2 | continue; |
3025 | 8 | IRB.CreateAlignedStore(MSV.getShadow(A), Base, kShadowTLSAlignment); |
3026 | 8 | } |
3027 | 12 | } |
3028 | 7 | Constant *OverflowSize = |
3029 | 7 | ConstantInt::get(IRB.getInt64Ty(), OverflowOffset - AMD64FpEndOffset); |
3030 | 7 | IRB.CreateStore(OverflowSize, MS.VAArgOverflowSizeTLS); |
3031 | 7 | } |
3032 | | |
3033 | | /// \brief Compute the shadow address for a given va_arg. |
3034 | | Value *getShadowPtrForVAArgument(Type *Ty, IRBuilder<> &IRB, |
3035 | 12 | int ArgOffset) { |
3036 | 12 | Value *Base = IRB.CreatePointerCast(MS.VAArgTLS, MS.IntptrTy); |
3037 | 12 | Base = IRB.CreateAdd(Base, ConstantInt::get(MS.IntptrTy, ArgOffset)); |
3038 | 12 | return IRB.CreateIntToPtr(Base, PointerType::get(MSV.getShadowTy(Ty), 0), |
3039 | 12 | "_msarg"); |
3040 | 12 | } |
3041 | | |
3042 | 2 | void visitVAStartInst(VAStartInst &I) override { |
3043 | 2 | if (F.getCallingConv() == CallingConv::Win64) |
3044 | 0 | return; |
3045 | 2 | IRBuilder<> IRB(&I); |
3046 | 2 | VAStartInstrumentationList.push_back(&I); |
3047 | 2 | Value *VAListTag = I.getArgOperand(0); |
3048 | 2 | Value *ShadowPtr = MSV.getShadowPtr(VAListTag, IRB.getInt8Ty(), IRB); |
3049 | 2 | |
3050 | 2 | // Unpoison the whole __va_list_tag. |
3051 | 2 | // FIXME: magic ABI constants. |
3052 | 2 | IRB.CreateMemSet(ShadowPtr, Constant::getNullValue(IRB.getInt8Ty()), |
3053 | 2 | /* size */24, /* alignment */8, false); |
3054 | 2 | } |
3055 | | |
3056 | 2 | void visitVACopyInst(VACopyInst &I) override { |
3057 | 2 | if (F.getCallingConv() == CallingConv::Win64) |
3058 | 0 | return; |
3059 | 2 | IRBuilder<> IRB(&I); |
3060 | 2 | Value *VAListTag = I.getArgOperand(0); |
3061 | 2 | Value *ShadowPtr = MSV.getShadowPtr(VAListTag, IRB.getInt8Ty(), IRB); |
3062 | 2 | |
3063 | 2 | // Unpoison the whole __va_list_tag. |
3064 | 2 | // FIXME: magic ABI constants. |
3065 | 2 | IRB.CreateMemSet(ShadowPtr, Constant::getNullValue(IRB.getInt8Ty()), |
3066 | 2 | /* size */24, /* alignment */8, false); |
3067 | 2 | } |
3068 | | |
3069 | 344 | void finalizeInstrumentation() override { |
3070 | 344 | assert(!VAArgOverflowSize && !VAArgTLSCopy && |
3071 | 344 | "finalizeInstrumentation called twice"); |
3072 | 344 | if (!VAStartInstrumentationList.empty()344 ) { |
3073 | 2 | // If there is a va_start in this function, make a backup copy of |
3074 | 2 | // va_arg_tls somewhere in the function entry block. |
3075 | 2 | IRBuilder<> IRB(F.getEntryBlock().getFirstNonPHI()); |
3076 | 2 | VAArgOverflowSize = IRB.CreateLoad(MS.VAArgOverflowSizeTLS); |
3077 | 2 | Value *CopySize = |
3078 | 2 | IRB.CreateAdd(ConstantInt::get(MS.IntptrTy, AMD64FpEndOffset), |
3079 | 2 | VAArgOverflowSize); |
3080 | 2 | VAArgTLSCopy = IRB.CreateAlloca(Type::getInt8Ty(*MS.C), CopySize); |
3081 | 2 | IRB.CreateMemCpy(VAArgTLSCopy, MS.VAArgTLS, CopySize, 8); |
3082 | 2 | } |
3083 | 344 | |
3084 | 344 | // Instrument va_start. |
3085 | 344 | // Copy va_list shadow from the backup copy of the TLS contents. |
3086 | 346 | for (size_t i = 0, n = VAStartInstrumentationList.size(); i < n346 ; i++2 ) { |
3087 | 2 | CallInst *OrigInst = VAStartInstrumentationList[i]; |
3088 | 2 | IRBuilder<> IRB(OrigInst->getNextNode()); |
3089 | 2 | Value *VAListTag = OrigInst->getArgOperand(0); |
3090 | 2 | |
3091 | 2 | Value *RegSaveAreaPtrPtr = |
3092 | 2 | IRB.CreateIntToPtr( |
3093 | 2 | IRB.CreateAdd(IRB.CreatePtrToInt(VAListTag, MS.IntptrTy), |
3094 | 2 | ConstantInt::get(MS.IntptrTy, 16)), |
3095 | 2 | Type::getInt64PtrTy(*MS.C)); |
3096 | 2 | Value *RegSaveAreaPtr = IRB.CreateLoad(RegSaveAreaPtrPtr); |
3097 | 2 | Value *RegSaveAreaShadowPtr = |
3098 | 2 | MSV.getShadowPtr(RegSaveAreaPtr, IRB.getInt8Ty(), IRB); |
3099 | 2 | IRB.CreateMemCpy(RegSaveAreaShadowPtr, VAArgTLSCopy, |
3100 | 2 | AMD64FpEndOffset, 16); |
3101 | 2 | |
3102 | 2 | Value *OverflowArgAreaPtrPtr = |
3103 | 2 | IRB.CreateIntToPtr( |
3104 | 2 | IRB.CreateAdd(IRB.CreatePtrToInt(VAListTag, MS.IntptrTy), |
3105 | 2 | ConstantInt::get(MS.IntptrTy, 8)), |
3106 | 2 | Type::getInt64PtrTy(*MS.C)); |
3107 | 2 | Value *OverflowArgAreaPtr = IRB.CreateLoad(OverflowArgAreaPtrPtr); |
3108 | 2 | Value *OverflowArgAreaShadowPtr = |
3109 | 2 | MSV.getShadowPtr(OverflowArgAreaPtr, IRB.getInt8Ty(), IRB); |
3110 | 2 | Value *SrcPtr = IRB.CreateConstGEP1_32(IRB.getInt8Ty(), VAArgTLSCopy, |
3111 | 2 | AMD64FpEndOffset); |
3112 | 2 | IRB.CreateMemCpy(OverflowArgAreaShadowPtr, SrcPtr, VAArgOverflowSize, 16); |
3113 | 2 | } |
3114 | 344 | } |
3115 | | }; |
3116 | | |
3117 | | /// \brief MIPS64-specific implementation of VarArgHelper. |
3118 | | struct VarArgMIPS64Helper : public VarArgHelper { |
3119 | | Function &F; |
3120 | | MemorySanitizer &MS; |
3121 | | MemorySanitizerVisitor &MSV; |
3122 | | Value *VAArgTLSCopy; |
3123 | | Value *VAArgSize; |
3124 | | |
3125 | | SmallVector<CallInst*, 16> VAStartInstrumentationList; |
3126 | | |
3127 | | VarArgMIPS64Helper(Function &F, MemorySanitizer &MS, |
3128 | | MemorySanitizerVisitor &MSV) |
3129 | | : F(F), MS(MS), MSV(MSV), VAArgTLSCopy(nullptr), |
3130 | 8 | VAArgSize(nullptr) {} |
3131 | | |
3132 | 4 | void visitCallSite(CallSite &CS, IRBuilder<> &IRB) override { |
3133 | 4 | unsigned VAArgOffset = 0; |
3134 | 4 | const DataLayout &DL = F.getParent()->getDataLayout(); |
3135 | 4 | for (CallSite::arg_iterator ArgIt = CS.arg_begin() + |
3136 | 4 | CS.getFunctionType()->getNumParams(), End = CS.arg_end(); |
3137 | 14 | ArgIt != End14 ; ++ArgIt10 ) { |
3138 | 10 | llvm::Triple TargetTriple(F.getParent()->getTargetTriple()); |
3139 | 10 | Value *A = *ArgIt; |
3140 | 10 | Value *Base; |
3141 | 10 | uint64_t ArgSize = DL.getTypeAllocSize(A->getType()); |
3142 | 10 | if (TargetTriple.getArch() == llvm::Triple::mips6410 ) { |
3143 | 5 | // Adjusting the shadow for argument with size < 8 to match the placement |
3144 | 5 | // of bits in big endian system |
3145 | 5 | if (ArgSize < 8) |
3146 | 1 | VAArgOffset += (8 - ArgSize); |
3147 | 5 | } |
3148 | 10 | Base = getShadowPtrForVAArgument(A->getType(), IRB, VAArgOffset); |
3149 | 10 | VAArgOffset += ArgSize; |
3150 | 10 | VAArgOffset = alignTo(VAArgOffset, 8); |
3151 | 10 | IRB.CreateAlignedStore(MSV.getShadow(A), Base, kShadowTLSAlignment); |
3152 | 10 | } |
3153 | 4 | |
3154 | 4 | Constant *TotalVAArgSize = ConstantInt::get(IRB.getInt64Ty(), VAArgOffset); |
3155 | 4 | // Here using VAArgOverflowSizeTLS as VAArgSizeTLS to avoid creation of |
3156 | 4 | // a new class member i.e. it is the total size of all VarArgs. |
3157 | 4 | IRB.CreateStore(TotalVAArgSize, MS.VAArgOverflowSizeTLS); |
3158 | 4 | } |
3159 | | |
3160 | | /// \brief Compute the shadow address for a given va_arg. |
3161 | | Value *getShadowPtrForVAArgument(Type *Ty, IRBuilder<> &IRB, |
3162 | 10 | int ArgOffset) { |
3163 | 10 | Value *Base = IRB.CreatePointerCast(MS.VAArgTLS, MS.IntptrTy); |
3164 | 10 | Base = IRB.CreateAdd(Base, ConstantInt::get(MS.IntptrTy, ArgOffset)); |
3165 | 10 | return IRB.CreateIntToPtr(Base, PointerType::get(MSV.getShadowTy(Ty), 0), |
3166 | 10 | "_msarg"); |
3167 | 10 | } |
3168 | | |
3169 | 2 | void visitVAStartInst(VAStartInst &I) override { |
3170 | 2 | IRBuilder<> IRB(&I); |
3171 | 2 | VAStartInstrumentationList.push_back(&I); |
3172 | 2 | Value *VAListTag = I.getArgOperand(0); |
3173 | 2 | Value *ShadowPtr = MSV.getShadowPtr(VAListTag, IRB.getInt8Ty(), IRB); |
3174 | 2 | IRB.CreateMemSet(ShadowPtr, Constant::getNullValue(IRB.getInt8Ty()), |
3175 | 2 | /* size */8, /* alignment */8, false); |
3176 | 2 | } |
3177 | | |
3178 | 0 | void visitVACopyInst(VACopyInst &I) override { |
3179 | 0 | IRBuilder<> IRB(&I); |
3180 | 0 | Value *VAListTag = I.getArgOperand(0); |
3181 | 0 | Value *ShadowPtr = MSV.getShadowPtr(VAListTag, IRB.getInt8Ty(), IRB); |
3182 | 0 | // Unpoison the whole __va_list_tag. |
3183 | 0 | // FIXME: magic ABI constants. |
3184 | 0 | IRB.CreateMemSet(ShadowPtr, Constant::getNullValue(IRB.getInt8Ty()), |
3185 | 0 | /* size */8, /* alignment */8, false); |
3186 | 0 | } |
3187 | | |
3188 | 8 | void finalizeInstrumentation() override { |
3189 | 8 | assert(!VAArgSize && !VAArgTLSCopy && |
3190 | 8 | "finalizeInstrumentation called twice"); |
3191 | 8 | IRBuilder<> IRB(F.getEntryBlock().getFirstNonPHI()); |
3192 | 8 | VAArgSize = IRB.CreateLoad(MS.VAArgOverflowSizeTLS); |
3193 | 8 | Value *CopySize = IRB.CreateAdd(ConstantInt::get(MS.IntptrTy, 0), |
3194 | 8 | VAArgSize); |
3195 | 8 | |
3196 | 8 | if (!VAStartInstrumentationList.empty()8 ) { |
3197 | 2 | // If there is a va_start in this function, make a backup copy of |
3198 | 2 | // va_arg_tls somewhere in the function entry block. |
3199 | 2 | VAArgTLSCopy = IRB.CreateAlloca(Type::getInt8Ty(*MS.C), CopySize); |
3200 | 2 | IRB.CreateMemCpy(VAArgTLSCopy, MS.VAArgTLS, CopySize, 8); |
3201 | 2 | } |
3202 | 8 | |
3203 | 8 | // Instrument va_start. |
3204 | 8 | // Copy va_list shadow from the backup copy of the TLS contents. |
3205 | 10 | for (size_t i = 0, n = VAStartInstrumentationList.size(); i < n10 ; i++2 ) { |
3206 | 2 | CallInst *OrigInst = VAStartInstrumentationList[i]; |
3207 | 2 | IRBuilder<> IRB(OrigInst->getNextNode()); |
3208 | 2 | Value *VAListTag = OrigInst->getArgOperand(0); |
3209 | 2 | Value *RegSaveAreaPtrPtr = |
3210 | 2 | IRB.CreateIntToPtr(IRB.CreatePtrToInt(VAListTag, MS.IntptrTy), |
3211 | 2 | Type::getInt64PtrTy(*MS.C)); |
3212 | 2 | Value *RegSaveAreaPtr = IRB.CreateLoad(RegSaveAreaPtrPtr); |
3213 | 2 | Value *RegSaveAreaShadowPtr = |
3214 | 2 | MSV.getShadowPtr(RegSaveAreaPtr, IRB.getInt8Ty(), IRB); |
3215 | 2 | IRB.CreateMemCpy(RegSaveAreaShadowPtr, VAArgTLSCopy, CopySize, 8); |
3216 | 2 | } |
3217 | 8 | } |
3218 | | }; |
3219 | | |
3220 | | |
3221 | | /// \brief AArch64-specific implementation of VarArgHelper. |
3222 | | struct VarArgAArch64Helper : public VarArgHelper { |
3223 | | static const unsigned kAArch64GrArgSize = 64; |
3224 | | static const unsigned kAArch64VrArgSize = 128; |
3225 | | |
3226 | | static const unsigned AArch64GrBegOffset = 0; |
3227 | | static const unsigned AArch64GrEndOffset = kAArch64GrArgSize; |
3228 | | // Make VR space aligned to 16 bytes. |
3229 | | static const unsigned AArch64VrBegOffset = AArch64GrEndOffset; |
3230 | | static const unsigned AArch64VrEndOffset = AArch64VrBegOffset |
3231 | | + kAArch64VrArgSize; |
3232 | | static const unsigned AArch64VAEndOffset = AArch64VrEndOffset; |
3233 | | |
3234 | | Function &F; |
3235 | | MemorySanitizer &MS; |
3236 | | MemorySanitizerVisitor &MSV; |
3237 | | Value *VAArgTLSCopy; |
3238 | | Value *VAArgOverflowSize; |
3239 | | |
3240 | | SmallVector<CallInst*, 16> VAStartInstrumentationList; |
3241 | | |
3242 | | VarArgAArch64Helper(Function &F, MemorySanitizer &MS, |
3243 | | MemorySanitizerVisitor &MSV) |
3244 | | : F(F), MS(MS), MSV(MSV), VAArgTLSCopy(nullptr), |
3245 | 3 | VAArgOverflowSize(nullptr) {} |
3246 | | |
3247 | | enum ArgKind { AK_GeneralPurpose, AK_FloatingPoint, AK_Memory }; |
3248 | | |
3249 | 12 | ArgKind classifyArgument(Value* arg) { |
3250 | 12 | Type *T = arg->getType(); |
3251 | 12 | if (T->isFPOrFPVectorTy()) |
3252 | 3 | return AK_FloatingPoint; |
3253 | 9 | if (9 (T->isIntegerTy() && 9 T->getPrimitiveSizeInBits() <= 649 ) |
3254 | 0 | || (T->isPointerTy())) |
3255 | 9 | return AK_GeneralPurpose; |
3256 | 0 | return AK_Memory; |
3257 | 0 | } |
3258 | | |
3259 | | // The instrumentation stores the argument shadow in a non ABI-specific |
3260 | | // format because it does not know which argument is named (since Clang, |
3261 | | // like x86_64 case, lowers the va_args in the frontend and this pass only |
3262 | | // sees the low level code that deals with va_list internals). |
3263 | | // The first seven GR registers are saved in the first 56 bytes of the |
3264 | | // va_arg tls arra, followers by the first 8 FP/SIMD registers, and then |
3265 | | // the remaining arguments. |
3266 | | // Using constant offset within the va_arg TLS array allows fast copy |
3267 | | // in the finalize instrumentation. |
3268 | 1 | void visitCallSite(CallSite &CS, IRBuilder<> &IRB) override { |
3269 | 1 | unsigned GrOffset = AArch64GrBegOffset; |
3270 | 1 | unsigned VrOffset = AArch64VrBegOffset; |
3271 | 1 | unsigned OverflowOffset = AArch64VAEndOffset; |
3272 | 1 | |
3273 | 1 | const DataLayout &DL = F.getParent()->getDataLayout(); |
3274 | 1 | for (CallSite::arg_iterator ArgIt = CS.arg_begin(), End = CS.arg_end(); |
3275 | 13 | ArgIt != End13 ; ++ArgIt12 ) { |
3276 | 12 | Value *A = *ArgIt; |
3277 | 12 | unsigned ArgNo = CS.getArgumentNo(ArgIt); |
3278 | 12 | bool IsFixed = ArgNo < CS.getFunctionType()->getNumParams(); |
3279 | 12 | ArgKind AK = classifyArgument(A); |
3280 | 12 | if (AK == AK_GeneralPurpose && 12 GrOffset >= AArch64GrEndOffset9 ) |
3281 | 1 | AK = AK_Memory; |
3282 | 12 | if (AK == AK_FloatingPoint && 12 VrOffset >= AArch64VrEndOffset3 ) |
3283 | 0 | AK = AK_Memory; |
3284 | 12 | Value *Base; |
3285 | 12 | switch (AK) { |
3286 | 8 | case AK_GeneralPurpose: |
3287 | 8 | Base = getShadowPtrForVAArgument(A->getType(), IRB, GrOffset); |
3288 | 8 | GrOffset += 8; |
3289 | 8 | break; |
3290 | 3 | case AK_FloatingPoint: |
3291 | 3 | Base = getShadowPtrForVAArgument(A->getType(), IRB, VrOffset); |
3292 | 3 | VrOffset += 16; |
3293 | 3 | break; |
3294 | 1 | case AK_Memory: |
3295 | 1 | // Don't count fixed arguments in the overflow area - va_start will |
3296 | 1 | // skip right over them. |
3297 | 1 | if (IsFixed) |
3298 | 0 | continue; |
3299 | 1 | uint64_t ArgSize = DL.getTypeAllocSize(A->getType()); |
3300 | 1 | Base = getShadowPtrForVAArgument(A->getType(), IRB, OverflowOffset); |
3301 | 1 | OverflowOffset += alignTo(ArgSize, 8); |
3302 | 1 | break; |
3303 | 12 | } |
3304 | 12 | // Count Gp/Vr fixed arguments to their respective offsets, but don't |
3305 | 12 | // bother to actually store a shadow. |
3306 | 12 | if (12 IsFixed12 ) |
3307 | 1 | continue; |
3308 | 11 | IRB.CreateAlignedStore(MSV.getShadow(A), Base, kShadowTLSAlignment); |
3309 | 11 | } |
3310 | 1 | Constant *OverflowSize = |
3311 | 1 | ConstantInt::get(IRB.getInt64Ty(), OverflowOffset - AArch64VAEndOffset); |
3312 | 1 | IRB.CreateStore(OverflowSize, MS.VAArgOverflowSizeTLS); |
3313 | 1 | } |
3314 | | |
3315 | | /// Compute the shadow address for a given va_arg. |
3316 | | Value *getShadowPtrForVAArgument(Type *Ty, IRBuilder<> &IRB, |
3317 | 12 | int ArgOffset) { |
3318 | 12 | Value *Base = IRB.CreatePointerCast(MS.VAArgTLS, MS.IntptrTy); |
3319 | 12 | Base = IRB.CreateAdd(Base, ConstantInt::get(MS.IntptrTy, ArgOffset)); |
3320 | 12 | return IRB.CreateIntToPtr(Base, PointerType::get(MSV.getShadowTy(Ty), 0), |
3321 | 12 | "_msarg"); |
3322 | 12 | } |
3323 | | |
3324 | 1 | void visitVAStartInst(VAStartInst &I) override { |
3325 | 1 | IRBuilder<> IRB(&I); |
3326 | 1 | VAStartInstrumentationList.push_back(&I); |
3327 | 1 | Value *VAListTag = I.getArgOperand(0); |
3328 | 1 | Value *ShadowPtr = MSV.getShadowPtr(VAListTag, IRB.getInt8Ty(), IRB); |
3329 | 1 | // Unpoison the whole __va_list_tag. |
3330 | 1 | // FIXME: magic ABI constants (size of va_list). |
3331 | 1 | IRB.CreateMemSet(ShadowPtr, Constant::getNullValue(IRB.getInt8Ty()), |
3332 | 1 | /* size */32, /* alignment */8, false); |
3333 | 1 | } |
3334 | | |
3335 | 0 | void visitVACopyInst(VACopyInst &I) override { |
3336 | 0 | IRBuilder<> IRB(&I); |
3337 | 0 | Value *VAListTag = I.getArgOperand(0); |
3338 | 0 | Value *ShadowPtr = MSV.getShadowPtr(VAListTag, IRB.getInt8Ty(), IRB); |
3339 | 0 | // Unpoison the whole __va_list_tag. |
3340 | 0 | // FIXME: magic ABI constants (size of va_list). |
3341 | 0 | IRB.CreateMemSet(ShadowPtr, Constant::getNullValue(IRB.getInt8Ty()), |
3342 | 0 | /* size */32, /* alignment */8, false); |
3343 | 0 | } |
3344 | | |
3345 | | // Retrieve a va_list field of 'void*' size. |
3346 | 3 | Value* getVAField64(IRBuilder<> &IRB, Value *VAListTag, int offset) { |
3347 | 3 | Value *SaveAreaPtrPtr = |
3348 | 3 | IRB.CreateIntToPtr( |
3349 | 3 | IRB.CreateAdd(IRB.CreatePtrToInt(VAListTag, MS.IntptrTy), |
3350 | 3 | ConstantInt::get(MS.IntptrTy, offset)), |
3351 | 3 | Type::getInt64PtrTy(*MS.C)); |
3352 | 3 | return IRB.CreateLoad(SaveAreaPtrPtr); |
3353 | 3 | } |
3354 | | |
3355 | | // Retrieve a va_list field of 'int' size. |
3356 | 2 | Value* getVAField32(IRBuilder<> &IRB, Value *VAListTag, int offset) { |
3357 | 2 | Value *SaveAreaPtr = |
3358 | 2 | IRB.CreateIntToPtr( |
3359 | 2 | IRB.CreateAdd(IRB.CreatePtrToInt(VAListTag, MS.IntptrTy), |
3360 | 2 | ConstantInt::get(MS.IntptrTy, offset)), |
3361 | 2 | Type::getInt32PtrTy(*MS.C)); |
3362 | 2 | Value *SaveArea32 = IRB.CreateLoad(SaveAreaPtr); |
3363 | 2 | return IRB.CreateSExt(SaveArea32, MS.IntptrTy); |
3364 | 2 | } |
3365 | | |
3366 | 3 | void finalizeInstrumentation() override { |
3367 | 3 | assert(!VAArgOverflowSize && !VAArgTLSCopy && |
3368 | 3 | "finalizeInstrumentation called twice"); |
3369 | 3 | if (!VAStartInstrumentationList.empty()3 ) { |
3370 | 1 | // If there is a va_start in this function, make a backup copy of |
3371 | 1 | // va_arg_tls somewhere in the function entry block. |
3372 | 1 | IRBuilder<> IRB(F.getEntryBlock().getFirstNonPHI()); |
3373 | 1 | VAArgOverflowSize = IRB.CreateLoad(MS.VAArgOverflowSizeTLS); |
3374 | 1 | Value *CopySize = |
3375 | 1 | IRB.CreateAdd(ConstantInt::get(MS.IntptrTy, AArch64VAEndOffset), |
3376 | 1 | VAArgOverflowSize); |
3377 | 1 | VAArgTLSCopy = IRB.CreateAlloca(Type::getInt8Ty(*MS.C), CopySize); |
3378 | 1 | IRB.CreateMemCpy(VAArgTLSCopy, MS.VAArgTLS, CopySize, 8); |
3379 | 1 | } |
3380 | 3 | |
3381 | 3 | Value *GrArgSize = ConstantInt::get(MS.IntptrTy, kAArch64GrArgSize); |
3382 | 3 | Value *VrArgSize = ConstantInt::get(MS.IntptrTy, kAArch64VrArgSize); |
3383 | 3 | |
3384 | 3 | // Instrument va_start, copy va_list shadow from the backup copy of |
3385 | 3 | // the TLS contents. |
3386 | 4 | for (size_t i = 0, n = VAStartInstrumentationList.size(); i < n4 ; i++1 ) { |
3387 | 1 | CallInst *OrigInst = VAStartInstrumentationList[i]; |
3388 | 1 | IRBuilder<> IRB(OrigInst->getNextNode()); |
3389 | 1 | |
3390 | 1 | Value *VAListTag = OrigInst->getArgOperand(0); |
3391 | 1 | |
3392 | 1 | // The variadic ABI for AArch64 creates two areas to save the incoming |
3393 | 1 | // argument registers (one for 64-bit general register xn-x7 and another |
3394 | 1 | // for 128-bit FP/SIMD vn-v7). |
3395 | 1 | // We need then to propagate the shadow arguments on both regions |
3396 | 1 | // 'va::__gr_top + va::__gr_offs' and 'va::__vr_top + va::__vr_offs'. |
3397 | 1 | // The remaning arguments are saved on shadow for 'va::stack'. |
3398 | 1 | // One caveat is it requires only to propagate the non-named arguments, |
3399 | 1 | // however on the call site instrumentation 'all' the arguments are |
3400 | 1 | // saved. So to copy the shadow values from the va_arg TLS array |
3401 | 1 | // we need to adjust the offset for both GR and VR fields based on |
3402 | 1 | // the __{gr,vr}_offs value (since they are stores based on incoming |
3403 | 1 | // named arguments). |
3404 | 1 | |
3405 | 1 | // Read the stack pointer from the va_list. |
3406 | 1 | Value *StackSaveAreaPtr = getVAField64(IRB, VAListTag, 0); |
3407 | 1 | |
3408 | 1 | // Read both the __gr_top and __gr_off and add them up. |
3409 | 1 | Value *GrTopSaveAreaPtr = getVAField64(IRB, VAListTag, 8); |
3410 | 1 | Value *GrOffSaveArea = getVAField32(IRB, VAListTag, 24); |
3411 | 1 | |
3412 | 1 | Value *GrRegSaveAreaPtr = IRB.CreateAdd(GrTopSaveAreaPtr, GrOffSaveArea); |
3413 | 1 | |
3414 | 1 | // Read both the __vr_top and __vr_off and add them up. |
3415 | 1 | Value *VrTopSaveAreaPtr = getVAField64(IRB, VAListTag, 16); |
3416 | 1 | Value *VrOffSaveArea = getVAField32(IRB, VAListTag, 28); |
3417 | 1 | |
3418 | 1 | Value *VrRegSaveAreaPtr = IRB.CreateAdd(VrTopSaveAreaPtr, VrOffSaveArea); |
3419 | 1 | |
3420 | 1 | // It does not know how many named arguments is being used and, on the |
3421 | 1 | // callsite all the arguments were saved. Since __gr_off is defined as |
3422 | 1 | // '0 - ((8 - named_gr) * 8)', the idea is to just propagate the variadic |
3423 | 1 | // argument by ignoring the bytes of shadow from named arguments. |
3424 | 1 | Value *GrRegSaveAreaShadowPtrOff = |
3425 | 1 | IRB.CreateAdd(GrArgSize, GrOffSaveArea); |
3426 | 1 | |
3427 | 1 | Value *GrRegSaveAreaShadowPtr = |
3428 | 1 | MSV.getShadowPtr(GrRegSaveAreaPtr, IRB.getInt8Ty(), IRB); |
3429 | 1 | |
3430 | 1 | Value *GrSrcPtr = IRB.CreateInBoundsGEP(IRB.getInt8Ty(), VAArgTLSCopy, |
3431 | 1 | GrRegSaveAreaShadowPtrOff); |
3432 | 1 | Value *GrCopySize = IRB.CreateSub(GrArgSize, GrRegSaveAreaShadowPtrOff); |
3433 | 1 | |
3434 | 1 | IRB.CreateMemCpy(GrRegSaveAreaShadowPtr, GrSrcPtr, GrCopySize, 8); |
3435 | 1 | |
3436 | 1 | // Again, but for FP/SIMD values. |
3437 | 1 | Value *VrRegSaveAreaShadowPtrOff = |
3438 | 1 | IRB.CreateAdd(VrArgSize, VrOffSaveArea); |
3439 | 1 | |
3440 | 1 | Value *VrRegSaveAreaShadowPtr = |
3441 | 1 | MSV.getShadowPtr(VrRegSaveAreaPtr, IRB.getInt8Ty(), IRB); |
3442 | 1 | |
3443 | 1 | Value *VrSrcPtr = IRB.CreateInBoundsGEP( |
3444 | 1 | IRB.getInt8Ty(), |
3445 | 1 | IRB.CreateInBoundsGEP(IRB.getInt8Ty(), VAArgTLSCopy, |
3446 | 1 | IRB.getInt32(AArch64VrBegOffset)), |
3447 | 1 | VrRegSaveAreaShadowPtrOff); |
3448 | 1 | Value *VrCopySize = IRB.CreateSub(VrArgSize, VrRegSaveAreaShadowPtrOff); |
3449 | 1 | |
3450 | 1 | IRB.CreateMemCpy(VrRegSaveAreaShadowPtr, VrSrcPtr, VrCopySize, 8); |
3451 | 1 | |
3452 | 1 | // And finally for remaining arguments. |
3453 | 1 | Value *StackSaveAreaShadowPtr = |
3454 | 1 | MSV.getShadowPtr(StackSaveAreaPtr, IRB.getInt8Ty(), IRB); |
3455 | 1 | |
3456 | 1 | Value *StackSrcPtr = |
3457 | 1 | IRB.CreateInBoundsGEP(IRB.getInt8Ty(), VAArgTLSCopy, |
3458 | 1 | IRB.getInt32(AArch64VAEndOffset)); |
3459 | 1 | |
3460 | 1 | IRB.CreateMemCpy(StackSaveAreaShadowPtr, StackSrcPtr, |
3461 | 1 | VAArgOverflowSize, 16); |
3462 | 1 | } |
3463 | 3 | } |
3464 | | }; |
3465 | | |
3466 | | /// \brief PowerPC64-specific implementation of VarArgHelper. |
3467 | | struct VarArgPowerPC64Helper : public VarArgHelper { |
3468 | | Function &F; |
3469 | | MemorySanitizer &MS; |
3470 | | MemorySanitizerVisitor &MSV; |
3471 | | Value *VAArgTLSCopy; |
3472 | | Value *VAArgSize; |
3473 | | |
3474 | | SmallVector<CallInst*, 16> VAStartInstrumentationList; |
3475 | | |
3476 | | VarArgPowerPC64Helper(Function &F, MemorySanitizer &MS, |
3477 | | MemorySanitizerVisitor &MSV) |
3478 | | : F(F), MS(MS), MSV(MSV), VAArgTLSCopy(nullptr), |
3479 | 17 | VAArgSize(nullptr) {} |
3480 | | |
3481 | 13 | void visitCallSite(CallSite &CS, IRBuilder<> &IRB) override { |
3482 | 13 | // For PowerPC, we need to deal with alignment of stack arguments - |
3483 | 13 | // they are mostly aligned to 8 bytes, but vectors and i128 arrays |
3484 | 13 | // are aligned to 16 bytes, byvals can be aligned to 8 or 16 bytes, |
3485 | 13 | // and QPX vectors are aligned to 32 bytes. For that reason, we |
3486 | 13 | // compute current offset from stack pointer (which is always properly |
3487 | 13 | // aligned), and offset for the first vararg, then subtract them. |
3488 | 13 | unsigned VAArgBase; |
3489 | 13 | llvm::Triple TargetTriple(F.getParent()->getTargetTriple()); |
3490 | 13 | // Parameter save area starts at 48 bytes from frame pointer for ABIv1, |
3491 | 13 | // and 32 bytes for ABIv2. This is usually determined by target |
3492 | 13 | // endianness, but in theory could be overriden by function attribute. |
3493 | 13 | // For simplicity, we ignore it here (it'd only matter for QPX vectors). |
3494 | 13 | if (TargetTriple.getArch() == llvm::Triple::ppc64) |
3495 | 7 | VAArgBase = 48; |
3496 | 13 | else |
3497 | 6 | VAArgBase = 32; |
3498 | 13 | unsigned VAArgOffset = VAArgBase; |
3499 | 13 | const DataLayout &DL = F.getParent()->getDataLayout(); |
3500 | 13 | for (CallSite::arg_iterator ArgIt = CS.arg_begin(), End = CS.arg_end(); |
3501 | 45 | ArgIt != End45 ; ++ArgIt32 ) { |
3502 | 32 | Value *A = *ArgIt; |
3503 | 32 | unsigned ArgNo = CS.getArgumentNo(ArgIt); |
3504 | 32 | bool IsFixed = ArgNo < CS.getFunctionType()->getNumParams(); |
3505 | 32 | bool IsByVal = CS.paramHasAttr(ArgNo, Attribute::ByVal); |
3506 | 32 | if (IsByVal32 ) { |
3507 | 4 | assert(A->getType()->isPointerTy()); |
3508 | 4 | Type *RealTy = A->getType()->getPointerElementType(); |
3509 | 4 | uint64_t ArgSize = DL.getTypeAllocSize(RealTy); |
3510 | 4 | uint64_t ArgAlign = CS.getParamAlignment(ArgNo); |
3511 | 4 | if (ArgAlign < 8) |
3512 | 0 | ArgAlign = 8; |
3513 | 4 | VAArgOffset = alignTo(VAArgOffset, ArgAlign); |
3514 | 4 | if (!IsFixed4 ) { |
3515 | 4 | Value *Base = getShadowPtrForVAArgument(RealTy, IRB, |
3516 | 4 | VAArgOffset - VAArgBase); |
3517 | 4 | IRB.CreateMemCpy(Base, MSV.getShadowPtr(A, IRB.getInt8Ty(), IRB), |
3518 | 4 | ArgSize, kShadowTLSAlignment); |
3519 | 4 | } |
3520 | 4 | VAArgOffset += alignTo(ArgSize, 8); |
3521 | 32 | } else { |
3522 | 28 | Value *Base; |
3523 | 28 | uint64_t ArgSize = DL.getTypeAllocSize(A->getType()); |
3524 | 28 | uint64_t ArgAlign = 8; |
3525 | 28 | if (A->getType()->isArrayTy()28 ) { |
3526 | 4 | // Arrays are aligned to element size, except for long double |
3527 | 4 | // arrays, which are aligned to 8 bytes. |
3528 | 4 | Type *ElementTy = A->getType()->getArrayElementType(); |
3529 | 4 | if (!ElementTy->isPPC_FP128Ty()) |
3530 | 4 | ArgAlign = DL.getTypeAllocSize(ElementTy); |
3531 | 28 | } else if (24 A->getType()->isVectorTy()24 ) { |
3532 | 3 | // Vectors are naturally aligned. |
3533 | 3 | ArgAlign = DL.getTypeAllocSize(A->getType()); |
3534 | 3 | } |
3535 | 28 | if (ArgAlign < 8) |
3536 | 0 | ArgAlign = 8; |
3537 | 28 | VAArgOffset = alignTo(VAArgOffset, ArgAlign); |
3538 | 28 | if (DL.isBigEndian()28 ) { |
3539 | 16 | // Adjusting the shadow for argument with size < 8 to match the placement |
3540 | 16 | // of bits in big endian system |
3541 | 16 | if (ArgSize < 8) |
3542 | 10 | VAArgOffset += (8 - ArgSize); |
3543 | 16 | } |
3544 | 28 | if (!IsFixed28 ) { |
3545 | 15 | Base = getShadowPtrForVAArgument(A->getType(), IRB, |
3546 | 15 | VAArgOffset - VAArgBase); |
3547 | 15 | IRB.CreateAlignedStore(MSV.getShadow(A), Base, kShadowTLSAlignment); |
3548 | 15 | } |
3549 | 28 | VAArgOffset += ArgSize; |
3550 | 28 | VAArgOffset = alignTo(VAArgOffset, 8); |
3551 | 28 | } |
3552 | 32 | if (IsFixed) |
3553 | 13 | VAArgBase = VAArgOffset; |
3554 | 32 | } |
3555 | 13 | |
3556 | 13 | Constant *TotalVAArgSize = ConstantInt::get(IRB.getInt64Ty(), |
3557 | 13 | VAArgOffset - VAArgBase); |
3558 | 13 | // Here using VAArgOverflowSizeTLS as VAArgSizeTLS to avoid creation of |
3559 | 13 | // a new class member i.e. it is the total size of all VarArgs. |
3560 | 13 | IRB.CreateStore(TotalVAArgSize, MS.VAArgOverflowSizeTLS); |
3561 | 13 | } |
3562 | | |
3563 | | /// \brief Compute the shadow address for a given va_arg. |
3564 | | Value *getShadowPtrForVAArgument(Type *Ty, IRBuilder<> &IRB, |
3565 | 19 | int ArgOffset) { |
3566 | 19 | Value *Base = IRB.CreatePointerCast(MS.VAArgTLS, MS.IntptrTy); |
3567 | 19 | Base = IRB.CreateAdd(Base, ConstantInt::get(MS.IntptrTy, ArgOffset)); |
3568 | 19 | return IRB.CreateIntToPtr(Base, PointerType::get(MSV.getShadowTy(Ty), 0), |
3569 | 19 | "_msarg"); |
3570 | 19 | } |
3571 | | |
3572 | 2 | void visitVAStartInst(VAStartInst &I) override { |
3573 | 2 | IRBuilder<> IRB(&I); |
3574 | 2 | VAStartInstrumentationList.push_back(&I); |
3575 | 2 | Value *VAListTag = I.getArgOperand(0); |
3576 | 2 | Value *ShadowPtr = MSV.getShadowPtr(VAListTag, IRB.getInt8Ty(), IRB); |
3577 | 2 | IRB.CreateMemSet(ShadowPtr, Constant::getNullValue(IRB.getInt8Ty()), |
3578 | 2 | /* size */8, /* alignment */8, false); |
3579 | 2 | } |
3580 | | |
3581 | 0 | void visitVACopyInst(VACopyInst &I) override { |
3582 | 0 | IRBuilder<> IRB(&I); |
3583 | 0 | Value *VAListTag = I.getArgOperand(0); |
3584 | 0 | Value *ShadowPtr = MSV.getShadowPtr(VAListTag, IRB.getInt8Ty(), IRB); |
3585 | 0 | // Unpoison the whole __va_list_tag. |
3586 | 0 | // FIXME: magic ABI constants. |
3587 | 0 | IRB.CreateMemSet(ShadowPtr, Constant::getNullValue(IRB.getInt8Ty()), |
3588 | 0 | /* size */8, /* alignment */8, false); |
3589 | 0 | } |
3590 | | |
3591 | 17 | void finalizeInstrumentation() override { |
3592 | 17 | assert(!VAArgSize && !VAArgTLSCopy && |
3593 | 17 | "finalizeInstrumentation called twice"); |
3594 | 17 | IRBuilder<> IRB(F.getEntryBlock().getFirstNonPHI()); |
3595 | 17 | VAArgSize = IRB.CreateLoad(MS.VAArgOverflowSizeTLS); |
3596 | 17 | Value *CopySize = IRB.CreateAdd(ConstantInt::get(MS.IntptrTy, 0), |
3597 | 17 | VAArgSize); |
3598 | 17 | |
3599 | 17 | if (!VAStartInstrumentationList.empty()17 ) { |
3600 | 2 | // If there is a va_start in this function, make a backup copy of |
3601 | 2 | // va_arg_tls somewhere in the function entry block. |
3602 | 2 | VAArgTLSCopy = IRB.CreateAlloca(Type::getInt8Ty(*MS.C), CopySize); |
3603 | 2 | IRB.CreateMemCpy(VAArgTLSCopy, MS.VAArgTLS, CopySize, 8); |
3604 | 2 | } |
3605 | 17 | |
3606 | 17 | // Instrument va_start. |
3607 | 17 | // Copy va_list shadow from the backup copy of the TLS contents. |
3608 | 19 | for (size_t i = 0, n = VAStartInstrumentationList.size(); i < n19 ; i++2 ) { |
3609 | 2 | CallInst *OrigInst = VAStartInstrumentationList[i]; |
3610 | 2 | IRBuilder<> IRB(OrigInst->getNextNode()); |
3611 | 2 | Value *VAListTag = OrigInst->getArgOperand(0); |
3612 | 2 | Value *RegSaveAreaPtrPtr = |
3613 | 2 | IRB.CreateIntToPtr(IRB.CreatePtrToInt(VAListTag, MS.IntptrTy), |
3614 | 2 | Type::getInt64PtrTy(*MS.C)); |
3615 | 2 | Value *RegSaveAreaPtr = IRB.CreateLoad(RegSaveAreaPtrPtr); |
3616 | 2 | Value *RegSaveAreaShadowPtr = |
3617 | 2 | MSV.getShadowPtr(RegSaveAreaPtr, IRB.getInt8Ty(), IRB); |
3618 | 2 | IRB.CreateMemCpy(RegSaveAreaShadowPtr, VAArgTLSCopy, CopySize, 8); |
3619 | 2 | } |
3620 | 17 | } |
3621 | | }; |
3622 | | |
3623 | | /// \brief A no-op implementation of VarArgHelper. |
3624 | | struct VarArgNoOpHelper : public VarArgHelper { |
3625 | | VarArgNoOpHelper(Function &F, MemorySanitizer &MS, |
3626 | 1 | MemorySanitizerVisitor &MSV) {} |
3627 | | |
3628 | 0 | void visitCallSite(CallSite &CS, IRBuilder<> &IRB) override {} |
3629 | | |
3630 | 1 | void visitVAStartInst(VAStartInst &I) override {} |
3631 | | |
3632 | 0 | void visitVACopyInst(VACopyInst &I) override {} |
3633 | | |
3634 | 1 | void finalizeInstrumentation() override {} |
3635 | | }; |
3636 | | |
3637 | | VarArgHelper *CreateVarArgHelper(Function &Func, MemorySanitizer &Msan, |
3638 | 373 | MemorySanitizerVisitor &Visitor) { |
3639 | 373 | // VarArg handling is only implemented on AMD64. False positives are possible |
3640 | 373 | // on other platforms. |
3641 | 373 | llvm::Triple TargetTriple(Func.getParent()->getTargetTriple()); |
3642 | 373 | if (TargetTriple.getArch() == llvm::Triple::x86_64) |
3643 | 344 | return new VarArgAMD64Helper(Func, Msan, Visitor); |
3644 | 29 | else if (29 TargetTriple.getArch() == llvm::Triple::mips64 || |
3645 | 25 | TargetTriple.getArch() == llvm::Triple::mips64el) |
3646 | 8 | return new VarArgMIPS64Helper(Func, Msan, Visitor); |
3647 | 21 | else if (21 TargetTriple.getArch() == llvm::Triple::aarch6421 ) |
3648 | 3 | return new VarArgAArch64Helper(Func, Msan, Visitor); |
3649 | 18 | else if (18 TargetTriple.getArch() == llvm::Triple::ppc64 || |
3650 | 9 | TargetTriple.getArch() == llvm::Triple::ppc64le) |
3651 | 17 | return new VarArgPowerPC64Helper(Func, Msan, Visitor); |
3652 | 18 | else |
3653 | 1 | return new VarArgNoOpHelper(Func, Msan, Visitor); |
3654 | 0 | } |
3655 | | |
3656 | | } // anonymous namespace |
3657 | | |
3658 | 437 | bool MemorySanitizer::runOnFunction(Function &F) { |
3659 | 437 | if (&F == MsanCtorFunction) |
3660 | 64 | return false; |
3661 | 373 | MemorySanitizerVisitor Visitor(F, *this); |
3662 | 373 | |
3663 | 373 | // Clear out readonly/readnone attributes. |
3664 | 373 | AttrBuilder B; |
3665 | 373 | B.addAttribute(Attribute::ReadOnly) |
3666 | 373 | .addAttribute(Attribute::ReadNone); |
3667 | 373 | F.removeAttributes(AttributeList::FunctionIndex, B); |
3668 | 373 | |
3669 | 373 | return Visitor.runOnFunction(); |
3670 | 373 | } |