[asan] Enable StackSafetyAnalysis by default #3

MaskRay · 2024-01-07T04:12:24Z

StackSafetyAnalysis determines whether stack-allocated variables are
safe from memory access bugs and allows removing certain unneeded
instrumentations.
(hwasan enables StackSafetyAnalysis in https://reviews.llvm.org/D108381)

Test updates:

asan-stack-safety.ll: test the -asan-use-stack-safety=1 default
lifetime-uar-uas.ll: switch to an indexed store to prevent
StackSafetyAnalysis from optimizing out instrumentation for %c
alloca_vla_interact.cpp: add a load to prevent StackSafetyAnalysis
from optimizing out __asan_alloca_poison for the VLA array
scariness_score_test.cpp: add -asan-use-stack-safety=0 to make a load
of a __asan_poison_memory_region-poisoned local variable fail as
intended.
other .ll tests: add -asan-use-stack-safety=0

Created using spr 1.3.4

…vm#75394) Calling one of pthread join/detach interceptor on an already joined/detached thread causes asserts such as: AddressSanitizer: CHECK failed: sanitizer_thread_arg_retval.cpp:56 "((t)) != (0)" (0x0, 0x0) (tid=1236094) #0 0x555555634f8b in __asan::CheckUnwind() compiler-rt/lib/asan/asan_rtl.cpp:69:3 #1 0x55555564e06e in __sanitizer::CheckFailed(char const*, int, char const*, unsigned long long, unsigned long long) compiler-rt/lib/sanitizer_common/sanitizer_termination.cpp:86:24 #2 0x5555556491df in __sanitizer::ThreadArgRetval::BeforeJoin(unsigned long) const compiler-rt/lib/sanitizer_common/sanitizer_thread_arg_retval.cpp:56:3 #3 0x5555556198ed in Join<___interceptor_pthread_tryjoin_np(void*, void**)::<lambda()> > compiler-rt/lib/asan/../sanitizer_common/sanitizer_thread_arg_retval.h:74:26 llvm#4 0x5555556198ed in pthread_tryjoin_np compiler-rt/lib/asan/asan_interceptors.cpp:311:29 The assert are replaced by error codes.

The concurrent tests all do a pthread_join at the end, and concurrent_base.py stops after that pthread_join and sanity checks that only 1 thread is running. On macOS, after pthread_join() has completed, there can be an extra thread still running which is completing the details of that task asynchronously; this causes testsuite failures. When this happens, we see the second thread is in ``` frame #0: 0x0000000180ce7700 libsystem_kernel.dylib`__ulock_wake + 8 frame #1: 0x0000000180d25ad4 libsystem_pthread.dylib`_pthread_joiner_wake + 52 frame #2: 0x0000000180d23c18 libsystem_pthread.dylib`_pthread_terminate + 384 frame #3: 0x0000000180d23a98 libsystem_pthread.dylib`_pthread_terminate_invoke + 92 frame llvm#4: 0x0000000180d26740 libsystem_pthread.dylib`_pthread_exit + 112 frame llvm#5: 0x0000000180d26040 libsystem_pthread.dylib`_pthread_start + 148 ``` there are none of the functions from the test file present on this thread. In this patch, instead of counting the number of threads, I iterate over the threads looking for functions from our test file (by name) and only count threads that have at least one of them. It's a lower frequency failure than the darwin kernel bug causing an extra step instruction mach exception when hardware breakpoint/watchpoints are used, but once I fixed that, this came up as the next most common failure for these tests. rdar://110555062

@0

…lvm#80904)" This reverts commit b1ac052. This commit breaks coroutine splitting for non-swift calling convention functions. In this example: ```ll ; ModuleID = 'repro.ll' source_filename = "stdlib/test/runtime/test_llcl.mojo" target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128" target triple = "x86_64-unknown-linux-gnu" @0 = internal constant { i32, i32 } { i32 trunc (i64 sub (i64 ptrtoint (ptr @craSH to i64), i64 ptrtoint (ptr getelementptr inbounds ({ i32, i32 }, ptr @0, i32 0, i32 1) to i64)) to i32), i32 64 } define dso_local void @af_suspend_fn(ptr %0, i64 %1, ptr %2) #0 { ret void } define dso_local void @craSH(ptr %0) #0 { %2 = call token @llvm.coro.id.async(i32 64, i32 8, i32 0, ptr @0) %3 = call ptr @llvm.coro.begin(token %2, ptr null) %4 = getelementptr inbounds { ptr, { ptr, ptr }, i64, { ptr, i1 }, i64, i64 }, ptr poison, i32 0, i32 0 %5 = call ptr @llvm.coro.async.resume() store ptr %5, ptr %4, align 8 %6 = call { ptr, ptr, ptr } (i32, ptr, ptr, ...) @llvm.coro.suspend.async.sl_p0p0p0s(i32 0, ptr %5, ptr @ctxt_proj_fn, ptr @af_suspend_fn, ptr poison, i64 -1, ptr poison) ret void } define dso_local ptr @ctxt_proj_fn(ptr %0) #0 { ret ptr %0 } ; Function Attrs: nomerge nounwind declare { ptr, ptr, ptr } @llvm.coro.suspend.async.sl_p0p0p0s(i32, ptr, ptr, ...) #1 ; Function Attrs: nounwind declare token @llvm.coro.id.async(i32, i32, i32, ptr) #2 ; Function Attrs: nounwind declare ptr @llvm.coro.begin(token, ptr writeonly) #2 ; Function Attrs: nomerge nounwind declare ptr @llvm.coro.async.resume() #1 attributes #0 = { "target-features"="+adx,+aes,+avx,+avx2,+bmi,+bmi2,+clflushopt,+clwb,+clzero,+crc32,+cx16,+cx8,+f16c,+fma,+fsgsbase,+fxsr,+invpcid,+lzcnt,+mmx,+movbe,+mwaitx,+pclmul,+pku,+popcnt,+prfchw,+rdpid,+rdpru,+rdrnd,+rdseed,+sahf,+sha,+sse,+sse2,+sse3,+sse4.1,+sse4.2,+sse4a,+ssse3,+vaes,+vpclmulqdq,+wbnoinvd,+x87,+xsave,+xsavec,+xsaveopt,+xsaves" } attributes #1 = { nomerge nounwind } attributes #2 = { nounwind } ``` This verifier crashes after the `coro-split` pass with ``` cannot guarantee tail call due to mismatched parameter counts musttail call void @af_suspend_fn(ptr poison, i64 -1, ptr poison) LLVM ERROR: Broken function PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace. Stack dump: 0. Program arguments: opt ../../../reduced.ll -O0 #0 0x00007f1d89645c0e __interceptor_backtrace.part.0 /build/gcc-11-XeT9lY/gcc-11-11.4.0/build/x86_64-linux-gnu/libsanitizer/asan/../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:4193:28 #1 0x0000556d94d254f7 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) /home/ubuntu/modular/third-party/llvm-project/llvm/lib/Support/Unix/Signals.inc:723:22 #2 0x0000556d94d19a2f llvm::sys::RunSignalHandlers() /home/ubuntu/modular/third-party/llvm-project/llvm/lib/Support/Signals.cpp:105:20 #3 0x0000556d94d1aa42 SignalHandler(int) /home/ubuntu/modular/third-party/llvm-project/llvm/lib/Support/Unix/Signals.inc:371:36 llvm#4 0x00007f1d88e42520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520) llvm#5 0x00007f1d88e969fc __pthread_kill_implementation ./nptl/pthread_kill.c:44:76 llvm#6 0x00007f1d88e969fc __pthread_kill_internal ./nptl/pthread_kill.c:78:10 llvm#7 0x00007f1d88e969fc pthread_kill ./nptl/pthread_kill.c:89:10 llvm#8 0x00007f1d88e42476 gsignal ./signal/../sysdeps/posix/raise.c:27:6 llvm#9 0x00007f1d88e287f3 abort ./stdlib/abort.c:81:7 llvm#10 0x0000556d8944be01 std::vector<llvm::json::Value, std::allocator<llvm::json::Value>>::size() const /usr/include/c++/11/bits/stl_vector.h:919:40 llvm#11 0x0000556d8944be01 bool std::operator==<llvm::json::Value, std::allocator<llvm::json::Value>>(std::vector<llvm::json::Value, std::allocator<llvm::json::Value>> const&, std::vector<llvm::json::Value, std::allocator<llvm::json::Value>> const&) /usr/include/c++/11/bits/stl_vector.h:1893:23 llvm#12 0x0000556d8944be01 llvm::json::operator==(llvm::json::Array const&, llvm::json::Array const&) /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/Support/JSON.h:572:69 llvm#13 0x0000556d8944be01 llvm::json::operator==(llvm::json::Value const&, llvm::json::Value const&) (.cold) /home/ubuntu/modular/third-party/llvm-project/llvm/lib/Support/JSON.cpp:204:28 llvm#14 0x0000556d949ed2bd llvm::report_fatal_error(char const*, bool) /home/ubuntu/modular/third-party/llvm-project/llvm/lib/Support/ErrorHandling.cpp:82:70 llvm#15 0x0000556d8e37e876 llvm::SmallVectorBase<unsigned int>::size() const /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/ADT/SmallVector.h:91:32 llvm#16 0x0000556d8e37e876 llvm::SmallVectorTemplateCommon<llvm::DiagnosticInfoOptimizationBase::Argument, void>::end() /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/ADT/SmallVector.h:282:41 llvm#17 0x0000556d8e37e876 llvm::SmallVector<llvm::DiagnosticInfoOptimizationBase::Argument, 4u>::~SmallVector() /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/ADT/SmallVector.h:1215:24 llvm#18 0x0000556d8e37e876 llvm::DiagnosticInfoOptimizationBase::~DiagnosticInfoOptimizationBase() /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/IR/DiagnosticInfo.h:413:7 llvm#19 0x0000556d8e37e876 llvm::DiagnosticInfoIROptimization::~DiagnosticInfoIROptimization() /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/IR/DiagnosticInfo.h:622:7 llvm#20 0x0000556d8e37e876 llvm::OptimizationRemark::~OptimizationRemark() /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/IR/DiagnosticInfo.h:689:7 llvm#21 0x0000556d8e37e876 operator() /home/ubuntu/modular/third-party/llvm-project/llvm/lib/Transforms/Coroutines/CoroSplit.cpp:2213:14 llvm#22 0x0000556d8e37e876 emit<llvm::CoroSplitPass::run(llvm::LazyCallGraph::SCC&, llvm::CGSCCAnalysisManager&, llvm::LazyCallGraph&, llvm::CGSCCUpdateResult&)::<lambda()> > /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/Analysis/OptimizationRemarkEmitter.h:83:12 llvm#23 0x0000556d8e37e876 llvm::CoroSplitPass::run(llvm::LazyCallGraph::SCC&, llvm::AnalysisManager<llvm::LazyCallGraph::SCC, llvm::LazyCallGraph&>&, llvm::LazyCallGraph&, llvm::CGSCCUpdateResult&) /home/ubuntu/modular/third-party/llvm-project/llvm/lib/Transforms/Coroutines/CoroSplit.cpp:2212:13 llvm#24 0x0000556d8c36ecb1 llvm::detail::PassModel<llvm::LazyCallGraph::SCC, llvm::CoroSplitPass, llvm::AnalysisManager<llvm::LazyCallGraph::SCC, llvm::LazyCallGraph&>, llvm::LazyCallGraph&, llvm::CGSCCUpdateResult&>::run(llvm::LazyCallGraph::SCC&, llvm::AnalysisManager<llvm::LazyCallGraph::SCC, llvm::LazyCallGraph&>&, llvm::LazyCallGraph&, llvm::CGSCCUpdateResult&) /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/IR/PassManagerInternal.h:91:3 llvm#25 0x0000556d91c1a84f llvm::PassManager<llvm::LazyCallGraph::SCC, llvm::AnalysisManager<llvm::LazyCallGraph::SCC, llvm::LazyCallGraph&>, llvm::LazyCallGraph&, llvm::CGSCCUpdateResult&>::run(llvm::LazyCallGraph::SCC&, llvm::AnalysisManager<llvm::LazyCallGraph::SCC, llvm::LazyCallGraph&>&, llvm::LazyCallGraph&, llvm::CGSCCUpdateResult&) /home/ubuntu/modular/third-party/llvm-project/llvm/lib/Analysis/CGSCCPassManager.cpp:90:12 llvm#26 0x0000556d8c3690d1 llvm::detail::PassModel<llvm::LazyCallGraph::SCC, llvm::PassManager<llvm::LazyCallGraph::SCC, llvm::AnalysisManager<llvm::LazyCallGraph::SCC, llvm::LazyCallGraph&>, llvm::LazyCallGraph&, llvm::CGSCCUpdateResult&>, llvm::AnalysisManager<llvm::LazyCallGraph::SCC, llvm::LazyCallGraph&>, llvm::LazyCallGraph&, llvm::CGSCCUpdateResult&>::run(llvm::LazyCallGraph::SCC&, llvm::AnalysisManager<llvm::LazyCallGraph::SCC, llvm::LazyCallGraph&>&, llvm::LazyCallGraph&, llvm::CGSCCUpdateResult&) /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/IR/PassManagerInternal.h:91:3 llvm#27 0x0000556d91c2162d llvm::ModuleToPostOrderCGSCCPassAdaptor::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) /home/ubuntu/modular/third-party/llvm-project/llvm/lib/Analysis/CGSCCPassManager.cpp:278:18 llvm#28 0x0000556d8c369035 llvm::detail::PassModel<llvm::Module, llvm::ModuleToPostOrderCGSCCPassAdaptor, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/IR/PassManagerInternal.h:91:3 llvm#29 0x0000556d9457abc5 llvm::PassManager<llvm::Module, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/IR/PassManager.h:247:20 llvm#30 0x0000556d8e30979e llvm::CoroConditionalWrapper::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) /home/ubuntu/modular/third-party/llvm-project/llvm/lib/Transforms/Coroutines/CoroConditionalWrapper.cpp:19:74 llvm#31 0x0000556d8c365755 llvm::detail::PassModel<llvm::Module, llvm::CoroConditionalWrapper, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/IR/PassManagerInternal.h:91:3 llvm#32 0x0000556d9457abc5 llvm::PassManager<llvm::Module, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/IR/PassManager.h:247:20 llvm#33 0x0000556d89818556 llvm::SmallPtrSetImplBase::isSmall() const /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/ADT/SmallPtrSet.h:196:33 llvm#34 0x0000556d89818556 llvm::SmallPtrSetImplBase::~SmallPtrSetImplBase() /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/ADT/SmallPtrSet.h:84:17 llvm#35 0x0000556d89818556 llvm::SmallPtrSetImpl<llvm::AnalysisKey*>::~SmallPtrSetImpl() /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/ADT/SmallPtrSet.h:321:7 llvm#36 0x0000556d89818556 llvm::SmallPtrSet<llvm::AnalysisKey*, 2u>::~SmallPtrSet() /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/ADT/SmallPtrSet.h:427:7 llvm#37 0x0000556d89818556 llvm::PreservedAnalyses::~PreservedAnalyses() /home/ubuntu/modular/third-party/llvm-project/llvm/include/llvm/IR/Analysis.h:109:7 llvm#38 0x0000556d89818556 llvm::runPassPipeline(llvm::StringRef, llvm::Module&, llvm::TargetMachine*, llvm::TargetLibraryInfoImpl*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::StringRef, llvm::ArrayRef<llvm::PassPlugin>, llvm::ArrayRef<std::function<void (llvm::PassBuilder&)>>, llvm::opt_tool::OutputKind, llvm::opt_tool::VerifierKind, bool, bool, bool, bool, bool, bool, bool) /home/ubuntu/modular/third-party/llvm-project/llvm/tools/opt/NewPMDriver.cpp:532:10 llvm#39 0x0000556d897e3939 optMain /home/ubuntu/modular/third-party/llvm-project/llvm/tools/opt/optdriver.cpp:737:27 llvm#40 0x0000556d89455461 main /home/ubuntu/modular/third-party/llvm-project/llvm/tools/opt/opt.cpp:25:33 llvm#41 0x00007f1d88e29d90 __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:58:16 llvm#42 0x00007f1d88e29e40 call_init ./csu/../csu/libc-start.c:128:20 llvm#43 0x00007f1d88e29e40 __libc_start_main ./csu/../csu/libc-start.c:379:5 llvm#44 0x0000556d897b6335 _start (/home/ubuntu/modular/.derived/third-party/llvm-project/build-relwithdebinfo-asan/bin/opt+0x150c335) Aborted (core dumped)

TestCases/Misc/Linux/sigaction.cpp fails because dlsym() may call malloc on failure. And then the wrapped malloc appears to access thread local storage using global dynamic accesses, thus calling ___interceptor___tls_get_addr, before REAL(__tls_get_addr) has been set, so we get a crash inside ___interceptor___tls_get_addr. For example, this can happen when looking up __isoc23_scanf which might not exist in some libcs. Fix this by marking the thread local variable accessed inside the debug checks as "initial-exec", which does not require __tls_get_addr. This is probably a better alternative to llvm#83886. This fixes a different crash but is related to llvm#46204. Backtrace: ``` #0 0x0000000000000000 in ?? () #1 0x00007ffff6a9d89e in ___interceptor___tls_get_addr (arg=0x7ffff6b27be8) at /path/to/llvm/compiler-rt/lib/tsan/rtl/tsan_interceptors_posix.cpp:2759 #2 0x00007ffff6a46bc6 in __sanitizer::CheckedMutex::LockImpl (this=0x7ffff6b27be8, pc=140737331846066) at /path/to/llvm/compiler-rt/lib/sanitizer_common/sanitizer_mutex.cpp:218 #3 0x00007ffff6a448b2 in __sanitizer::CheckedMutex::Lock (this=0x7ffff6b27be8, this@entry=0x730000000580) at /path/to/llvm/compiler-rt/lib/tsan/rtl/../../sanitizer_common/sanitizer_mutex.h:129 llvm#4 __sanitizer::Mutex::Lock (this=0x7ffff6b27be8, this@entry=0x730000000580) at /path/to/llvm/compiler-rt/lib/tsan/rtl/../../sanitizer_common/sanitizer_mutex.h:167 llvm#5 0x00007ffff6abdbb2 in __sanitizer::GenericScopedLock<__sanitizer::Mutex>::GenericScopedLock (mu=0x730000000580, this=<optimized out>) at /path/to/llvm/compiler-rt/lib/tsan/rtl/../../sanitizer_common/sanitizer_mutex.h:383 llvm#6 __sanitizer::SizeClassAllocator64<__tsan::AP64>::GetFromAllocator (this=0x7ffff7487dc0 <__tsan::allocator_placeholder>, stat=stat@entry=0x7ffff570db68, class_id=11, chunks=chunks@entry=0x7ffff5702cc8, n_chunks=n_chunks@entry=128) at /path/to/llvm/compiler-rt/lib/tsan/rtl/../../sanitizer_common/sanitizer_allocator_primary64.h:207 llvm#7 0x00007ffff6abdaa0 in __sanitizer::SizeClassAllocator64LocalCache<__sanitizer::SizeClassAllocator64<__tsan::AP64> >::Refill (this=<optimized out>, c=c@entry=0x7ffff5702cb8, allocator=<optimized out>, class_id=<optimized out>) at /path/to/llvm/compiler-rt/lib/tsan/rtl/../../sanitizer_common/sanitizer_allocator_local_cache.h:103 llvm#8 0x00007ffff6abd731 in __sanitizer::SizeClassAllocator64LocalCache<__sanitizer::SizeClassAllocator64<__tsan::AP64> >::Allocate (this=0x7ffff6b27be8, allocator=0x7ffff5702cc8, class_id=140737311157448) at /path/to/llvm/compiler-rt/lib/tsan/rtl/../../sanitizer_common/sanitizer_allocator_local_cache.h:39 llvm#9 0x00007ffff6abc397 in __sanitizer::CombinedAllocator<__sanitizer::SizeClassAllocator64<__tsan::AP64>, __sanitizer::LargeMmapAllocatorPtrArrayDynamic>::Allocate (this=0x7ffff5702cc8, cache=0x7ffff6b27be8, size=<optimized out>, size@entry=175, alignment=alignment@entry=16) at /path/to/llvm/compiler-rt/lib/tsan/rtl/../../sanitizer_common/sanitizer_allocator_combined.h:69 llvm#10 0x00007ffff6abaa6a in __tsan::user_alloc_internal (thr=0x7ffff7ebd980, pc=140737331499943, sz=sz@entry=175, align=align@entry=16, signal=true) at /path/to/llvm/compiler-rt/lib/tsan/rtl/tsan_mman.cpp:198 llvm#11 0x00007ffff6abb0d1 in __tsan::user_alloc (thr=0x7ffff6b27be8, pc=140737331846066, sz=11, sz@entry=175) at /path/to/llvm/compiler-rt/lib/tsan/rtl/tsan_mman.cpp:223 llvm#12 0x00007ffff6a693b5 in ___interceptor_malloc (size=175) at /path/to/llvm/compiler-rt/lib/tsan/rtl/tsan_interceptors_posix.cpp:666 llvm#13 0x00007ffff7fce7f2 in malloc (size=175) at ../include/rtld-malloc.h:56 llvm#14 __GI__dl_exception_create_format (exception=exception@entry=0x7fffffffd0d0, objname=0x7ffff7fc3550 "/path/to/llvm/compiler-rt/cmake-build-all-sanitizers/lib/linux/libclang_rt.tsan-x86_64.so", fmt=fmt@entry=0x7ffff7ff2db9 "undefined symbol: %s%s%s") at ./elf/dl-exception.c:157 llvm#15 0x00007ffff7fd50e8 in _dl_lookup_symbol_x (undef_name=0x7ffff6af868b "__isoc23_scanf", undef_map=<optimized out>, ref=0x7fffffffd148, symbol_scope=<optimized out>, version=<optimized out>, type_class=0, flags=2, skip_map=0x7ffff7fc35e0) at ./elf/dl-lookup.c:793 --Type <RET> for more, q to quit, c to continue without paging-- llvm#16 0x00007ffff656d6ed in do_sym (handle=<optimized out>, name=0x7ffff6af868b "__isoc23_scanf", who=0x7ffff6a3bb84 <__interception::InterceptFunction(char const*, unsigned long*, unsigned long, unsigned long)+36>, vers=vers@entry=0x0, flags=flags@entry=2) at ./elf/dl-sym.c:146 llvm#17 0x00007ffff656d9dd in _dl_sym (handle=<optimized out>, name=<optimized out>, who=<optimized out>) at ./elf/dl-sym.c:195 llvm#18 0x00007ffff64a2854 in dlsym_doit (a=a@entry=0x7fffffffd3b0) at ./dlfcn/dlsym.c:40 llvm#19 0x00007ffff7fcc489 in __GI__dl_catch_exception (exception=exception@entry=0x7fffffffd310, operate=0x7ffff64a2840 <dlsym_doit>, args=0x7fffffffd3b0) at ./elf/dl-catch.c:237 llvm#20 0x00007ffff7fcc5af in _dl_catch_error (objname=0x7fffffffd368, errstring=0x7fffffffd370, mallocedp=0x7fffffffd367, operate=<optimized out>, args=<optimized out>) at ./elf/dl-catch.c:256 llvm#21 0x00007ffff64a2257 in _dlerror_run (operate=operate@entry=0x7ffff64a2840 <dlsym_doit>, args=args@entry=0x7fffffffd3b0) at ./dlfcn/dlerror.c:138 llvm#22 0x00007ffff64a28e5 in dlsym_implementation (dl_caller=<optimized out>, name=<optimized out>, handle=<optimized out>) at ./dlfcn/dlsym.c:54 llvm#23 ___dlsym (handle=<optimized out>, name=<optimized out>) at ./dlfcn/dlsym.c:68 llvm#24 0x00007ffff6a3bb84 in __interception::GetFuncAddr (name=0x7ffff6af868b "__isoc23_scanf", trampoline=140737311157448) at /path/to/llvm/compiler-rt/lib/interception/interception_linux.cpp:42 llvm#25 __interception::InterceptFunction (name=0x7ffff6af868b "__isoc23_scanf", ptr_to_real=0x7ffff74850e8 <__interception::real___isoc23_scanf>, func=11, trampoline=140737311157448) at /path/to/llvm/compiler-rt/lib/interception/interception_linux.cpp:61 llvm#26 0x00007ffff6a9f2d9 in InitializeCommonInterceptors () at /path/to/llvm/compiler-rt/lib/tsan/rtl/../../sanitizer_common/sanitizer_common_interceptors.inc:10315 ``` Reviewed By: vitalybuka, MaskRay Pull Request: llvm#83890

…ined member functions & member function templates (llvm#88963) Consider the following snippet from the discussion of CWG2847 on the core reflector: ``` template<typename T> concept C = sizeof(T) <= sizeof(long); template<typename T> struct A { template<typename U> void f(U) requires C<U>; // #1, declares a function template void g() requires C<T>; // #2, declares a function template<> void f(char); // #3, an explicit specialization of a function template that declares a function }; template<> template<typename U> void A<short>::f(U) requires C<U>; // llvm#4, an explicit specialization of a function template that declares a function template template<> template<> void A<int>::f(int); // llvm#5, an explicit specialization of a function template that declares a function template<> void A<long>::g(); // llvm#6, an explicit specialization of a function that declares a function ``` A number of problems exist: - Clang rejects `llvm#4` because the trailing _requires-clause_ has `U` substituted with the wrong template parameter depth when `Sema::AreConstraintExpressionsEqual` is called to determine whether it matches the trailing _requires-clause_ of the implicitly instantiated function template. - Clang rejects `llvm#5` because the function template specialization instantiated from `A<int>::f` has a trailing _requires-clause_, but `llvm#5` does not (nor can it have one as it isn't a templated function). - Clang rejects `llvm#6` for the same reasons it rejects `llvm#5`. This patch resolves these issues by making the following changes: - To fix `llvm#4`, `Sema::AreConstraintExpressionsEqual` is passed `FunctionTemplateDecl`s when comparing the trailing _requires-clauses_ of `llvm#4` and the function template instantiated from `#1`. - To fix `llvm#5` and `llvm#6`, the trailing _requires-clauses_ are not compared for explicit specializations that declare functions. In addition to these changes, `CheckMemberSpecialization` now considers constraint satisfaction/constraint partial ordering when determining which member function is specialized by an explicit specialization of a member function for an implicit instantiation of a class template (we previously would select the first function that has the same type as the explicit specialization). With constraints taken under consideration, we match EDG's behavior for these declarations.

...which caused issues like > ==42==ERROR: AddressSanitizer failed to deallocate 0x32 (50) bytes at address 0x117e0000 (error code: 28) > ==42==Cannot dump memory map on emscriptenAddressSanitizer: CHECK failed: sanitizer_common.cpp:81 "((0 && "unable to unmmap")) != (0)" (0x0, 0x0) (tid=288045824) > #0 0x14f73b0c in __asan::CheckUnwind()+0x14f73b0c (this.program+0x14f73b0c) > #1 0x14f8a3c2 in __sanitizer::CheckFailed(char const*, int, char const*, unsigned long long, unsigned long long)+0x14f8a3c2 (this.program+0x14f8a3c2) > #2 0x14f7d6e1 in __sanitizer::ReportMunmapFailureAndDie(void*, unsigned long, int, bool)+0x14f7d6e1 (this.program+0x14f7d6e1) > #3 0x14f81fbd in __sanitizer::UnmapOrDie(void*, unsigned long)+0x14f81fbd (this.program+0x14f81fbd) > llvm#4 0x14f875df in __sanitizer::SuppressionContext::ParseFromFile(char const*)+0x14f875df (this.program+0x14f875df) > llvm#5 0x14f74eab in __asan::InitializeSuppressions()+0x14f74eab (this.program+0x14f74eab) > llvm#6 0x14f73a1a in __asan::AsanInitInternal()+0x14f73a1a (this.program+0x14f73a1a) when trying to use an ASan suppressions file under Emscripten: Even though it would be considered OK by SUSv4, the Emscripten runtime states "We don't support partial munmapping" (see <emscripten-core/emscripten@f4115eb> "Implement MAP_ANONYMOUS on top of malloc in STANDALONE_WASM mode (llvm#16289)"). Co-authored-by: Stephan Bergmann <stephan.bergmann@allotropia.de>

…erSize (llvm#67657)" This reverts commit f0b3654. This commit triggers UB by reading an uninitialized variable. `UP.PartialThreshold` is used uninitialized in `getUnrollingPreferences()` when it is called from `LoopVectorizationPlanner::executePlan()`. In this case the `UP` variable is created on the stack and its fields are not initialized. ``` ==8802==WARNING: MemorySanitizer: use-of-uninitialized-value #0 0x557c0b081b99 in llvm::BasicTTIImplBase<llvm::X86TTIImpl>::getUnrollingPreferences(llvm::Loop*, llvm::ScalarEvolution&, llvm::TargetTransformInfo::UnrollingPreferences&, llvm::OptimizationRemarkEmitter*) llvm-project/llvm/include/llvm/CodeGen/BasicTTIImpl.h #1 0x557c0b07a40c in llvm::TargetTransformInfo::Model<llvm::X86TTIImpl>::getUnrollingPreferences(llvm::Loop*, llvm::ScalarEvolution&, llvm::TargetTransformInfo::UnrollingPreferences&, llvm::OptimizationRemarkEmitter*) llvm-project/llvm/include/llvm/Analysis/TargetTransformInfo.h:2277:17 #2 0x557c0f5d69ee in llvm::TargetTransformInfo::getUnrollingPreferences(llvm::Loop*, llvm::ScalarEvolution&, llvm::TargetTransformInfo::UnrollingPreferences&, llvm::OptimizationRemarkEmitter*) const llvm-project/llvm/lib/Analysis/TargetTransformInfo.cpp:387:19 #3 0x557c0e6b96a0 in llvm::LoopVectorizationPlanner::executePlan(llvm::ElementCount, unsigned int, llvm::VPlan&, llvm::InnerLoopVectorizer&, llvm::DominatorTree*, bool, llvm::DenseMap<llvm::SCEV const*, llvm::Value*, llvm::DenseMapInfo<llvm::SCEV const*, void>, llvm::detail::DenseMapPair<llvm::SCEV const*, llvm::Value*>> const*) llvm-project/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp:7624:7 llvm#4 0x557c0e6e4b63 in llvm::LoopVectorizePass::processLoop(llvm::Loop*) llvm-project/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp:10253:13 llvm#5 0x557c0e6f2429 in llvm::LoopVectorizePass::runImpl(llvm::Function&, llvm::ScalarEvolution&, llvm::LoopInfo&, llvm::TargetTransformInfo&, llvm::DominatorTree&, llvm::BlockFrequencyInfo*, llvm::TargetLibraryInfo*, llvm::DemandedBits&, llvm::AssumptionCache&, llvm::LoopAccessInfoManager&, llvm::OptimizationRemarkEmitter&, llvm::ProfileSummaryInfo*) llvm-project/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp:10344:30 llvm#6 0x557c0e6f2f97 in llvm::LoopVectorizePass::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) llvm-project/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp:10383:9 [...] Uninitialized value was created by an allocation of 'UP' in the stack frame #0 0x557c0e6b961e in llvm::LoopVectorizationPlanner::executePlan(llvm::ElementCount, unsigned int, llvm::VPlan&, llvm::InnerLoopVectorizer&, llvm::DominatorTree*, bool, llvm::DenseMap<llvm::SCEV const*, llvm::Value*, llvm::DenseMapInfo<llvm::SCEV const*, void>, llvm::detail::DenseMapPair<llvm::SCEV const*, llvm::Value*>> const*) llvm-project/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp:7623:3 ```

@src

See the following case: https://alive2.llvm.org/ce/z/A-fBki ``` define i3 @src(i3 %0) { %2 = mul i3 %0, %0 %3 = mul i3 %2, %0 %4 = mul i3 %3, %0 %5 = mul nsw i3 %4, %0 ret i3 %5 } define i3 @tgt(i3 %0) { %2 = mul i3 %0, %0 %5 = mul nsw i3 %2, %0 ret i3 %5 } ``` llvm@d7aeefe introduced weight reduction during weights combination of the same operand. As the weight of `%0` changes from 5 to 3, the nsw flag in `%5` should be dropped. However, the nsw flag isn't cleared by `RewriteExprTree` since `%5 = mul nsw i3 %0, %4` is not included in the range of `[ExpressionChangedStart, ExpressionChangedEnd)`. ``` Calculated Rank[] = 3 Combine negations for: %2 = mul i3 %0, %0 Calculated Rank[] = 4 Combine negations for: %3 = mul i3 %0, %2 Calculated Rank[] = 5 Combine negations for: %4 = mul i3 %0, %3 Calculated Rank[] = 6 Combine negations for: %5 = mul nsw i3 %0, %4 LINEARIZE: %5 = mul nsw i3 %0, %4 OPERAND: i3 %0 (1) ADD USES LEAF: i3 %0 (1) OPERAND: %4 = mul i3 %0, %3 (1) DIRECT ADD: %4 = mul i3 %0, %3 (1) OPERAND: i3 %0 (1) OPERAND: %3 = mul i3 %0, %2 (1) DIRECT ADD: %3 = mul i3 %0, %2 (1) OPERAND: i3 %0 (1) OPERAND: %2 = mul i3 %0, %0 (1) DIRECT ADD: %2 = mul i3 %0, %0 (1) OPERAND: i3 %0 (1) OPERAND: i3 %0 (1) RAIn: mul i3 [ %0, #3] [ %0, #3] [ %0, #3] RAOut: mul i3 [ %0, #3] [ %0, #3] [ %0, #3] RAOut after CSE reorder: mul i3 [ %0, #3] [ %0, #3] [ %0, #3] RA: %5 = mul nsw i3 %0, %4 TO: %5 = mul nsw i3 %4, %0 RA: %4 = mul i3 %0, %3 TO: %4 = mul i3 %0, %0 ``` The best way to fix this is to inform `RewriteExprTree` to clear flags of the whole expr tree when weight reduction happens. But I find that weight reduction based on Carmichael number never happens in practice. See the coverage result https://dtcxzyw.github.io/llvm-opt-benchmark/coverage/home/dtcxzyw/llvm-project/llvm/lib/Transforms/Scalar/Reassociate.cpp.html#L323 I think it would be better to drop `IncorporateWeight`. Fixes llvm#91417

[𝘀𝗽𝗿] initial version

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MaskRay closed this Jan 11, 2024

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[asan] Enable StackSafetyAnalysis by default #3

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[asan] Enable StackSafetyAnalysis by default #3

[asan] Enable StackSafetyAnalysis by default #3

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MaskRay commented Jan 7, 2024