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Correctly handle unroll directives that disable unrolling #5
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vzakhari
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Feb 7, 2025
flang/test/Integration/unroll.f90
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subroutine unroll_dir_0 | ||
integer :: a(10) | ||
!dir$ unroll 0 | ||
! CHECK: br i1 {{.*}}, label {{.*}}, label {{.*}}, !llvm.loop ![[UNROLL_DISABLE:.*]] |
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Shouldn't it be this way?
Suggested change
! CHECK: br i1 {{.*}}, label {{.*}}, label {{.*}}, !llvm.loop ![[UNROLL_DISABLE:.*]] | |
! CHECK: br i1 {{.*}}, label {{.*}}, label {{.*}}, !llvm.loop ![[UNROLL_DISABLE_ANNO:.*]] |
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I just pushed that fix but you beat me to it!
vzakhari
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vzakhari
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…ape]] on a member function no longer works. (llvm#126016)
…llvm#125143) …uffer ValueObjectDynamicValue::UpdateValue() assumes that the dynamic type found by GetDynamicTypeAndAddress() would return an address in the inferior. This commit makes it so it can deal with being passed a host address instead. This is needed downstream by the Swift fork. rdar://143357274
…#126171) In Sep 2016 and newer Darwin releases, debugserver uses libdyld SPI to gather information about the binaries loaded in a process. Before Sep 2016, lldb would inspect the dyld internal data structures directly itself to find this information. DynamicLoaderDarwin::UseDYLDSPI currently defaults to the old inspect-dyld-internal-structures method for binaries (DynamicLoaderMacOSXDYLD). If it detects that the Process' host OS version is new enough, it enables the newer libdyld SPI methods in debugserver (DynamicLoaderMacOS). This patch changes the default to use the new libdyld SPI interfaces. If the Process has a HostOS and it is one of the four specific OSes that existed in 2015 (Mac OS X, iOS, tvOS, watchOS) with an old version number, then we will enable the old DynamicLoader plugin. If this debug session is a corefile, we will always use the old DynamicLoader plugin -- the libdyld SPI cannot run against a corefile, lldb must read metadata or the dyld internal data structures in the corefile to find the loaded binaries.
llvm#126020) On some OS distros such as LoongArch Fedora 38 mate-5 [1], there are no macro definitions NT_LOONGARCH_HW_BREAK and NT_LOONGARCH_HW_WATCH in the system header, then there exist some errors when building LLDB on LoongArch. (1) Description of Problem: ``` llvm-project/lldb/source/Plugins/Process/Linux/NativeRegisterContextLinux_loongarch64.cpp:529:16: error: 'NT_LOONGARCH_HW_WATCH' was not declared in this scope; did you mean 'NT_LOONGARCH_LBT'? 529 | int regset = NT_LOONGARCH_HW_WATCH; | ^~~~~~~~~~~~~~~~~~~~~ | NT_LOONGARCH_LBT llvm-project/lldb/source/Plugins/Process/Linux/NativeRegisterContextLinux_loongarch64.cpp:543:12: error: 'NT_LOONGARCH_HW_BREAK' was not declared in this scope; did you mean 'NT_LOONGARCH_CSR'? 543 | regset = NT_LOONGARCH_HW_BREAK; | ^~~~~~~~~~~~~~~~~~~~~ | NT_LOONGARCH_CSR ``` (2) Steps to Reproduce: ``` git clone https://github.com/llvm/llvm-project.git mkdir -p llvm-project/llvm/build && cd llvm-project/llvm/build cmake .. -G "Ninja" \ -DCMAKE_BUILD_TYPE=Release \ -DLLVM_BUILD_RUNTIME=OFF \ -DLLVM_ENABLE_PROJECTS="clang;lldb" \ -DCMAKE_INSTALL_PREFIX=/usr/local/llvm \ -DLLVM_TARGETS_TO_BUILD="LoongArch" \ -DLLVM_HOST_TRIPLE=loongarch64-redhat-linux ninja ``` (3) Additional Info: Maybe there are no problems on the OS distros with newer glibc devel library, so this issue is related with OS distros. (4) Root Cause Analysis: This is because the related Linux kernel commit [2] was merged in 2023-02-25 and the glibc devel library has some delay with kernel, the glibc version of specified OS distros is not updated in time. (5) Final Solution: One way is to ask the maintainer of OS distros to update glibc devel library, but it is better to not depend on the glibc version. In order to avoid the build errors, just define NT_LOONGARCH_HW_BREAK and NT_LOONGARCH_HW_WATCH in LLDB if there are no these definitions in the system header. By the way, in order to fit within 80 columns, use C++-style comments for the new added NT_LOONGARCH_HW_BREAK and NT_LOONGARCH_HW_WATCH. While at it, for consistency, just modify the current NT_LOONGARCH_LSX and NT_LOONGARCH_LASX to C++-style comments too. [1] https://mirrors.wsyu.edu.cn/fedora/linux/development/rawhide/Everything/loongarch64/iso/livecd-fedora-mate-5.loongarch64.iso [2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=1a69f7a161a7 Signed-off-by: Tiezhu Yang <[email protected]>
…was missing Summary: This code is intended to block transformations if the call isn't present, however the way it's coded it silently lets it pass if the definition doesn't exist at all. This previously was always valid since we included the runtime as one giant blob so everything was always there, but now that we want to move towards separate ones, it's not quite correct.
This is a tiny change that can save up to 16 bytes of stack allocation, which is more beneficial on RV32 than RV64. cm.push allocates multiples of 16 bytes, but only uses a subset of those bytes for pushing callee-saved registers. Up to 12 (rv32) or 8 (rv64) bytes are left unused, depending on how many registers are pushed. Before this change, we told LLVM that the entire allocation was used, by creating a fixed stack object which covered the whole allocation. This change instead gives an accurate extent to the fixed stack object, to only cover the registers that have been pushed. This allows the PrologEpilogInserter to use any unused bytes for spills. Potentially this saves an extra move of the stack pointer after the push, because the push can allocate up to 48 more bytes than it needs for registers. We cannot do the same change for save/restore, because the restore routines restore in batches of `stackalign/(xlen/8)` registers, and we don't want to clobber the saved values of registers that we didn't tell the compiler we were saving/restoring - for instance `__riscv_restore_0` is used by the compiler when it only wants to save `ra`, but will end up restoring `ra` and `s0`.
Alive2: https://alive2.llvm.org/ce/z/6zLAYp Note: We can also apply this fix to the logic below (`if (Mask & AMask_NotAllOnes)`), but it seems unreachable.
… (NFC) (llvm#126175) I suggested using a lambda in llvm#126171 but @jasonmolenda missed it.
The current legality check for folding with EVL has incomplete verification for VF. This patch fixes the VF check, ensuring that tail folding with EVL is enabled only when a scalable VF is available. This allows loops that prefer tail folding with EVL but cannot use scalable VF vectorization to still be vectorized using a fixed VF, rather than abandoning vectorization entirely.
The config is currently not movable and because there are constructors the default move won't be generated, which prevents it from being moved. Also, it is not copyable because of the unique_ptr. This PR adds move constructor to allow moving it.
This was ultimately working around bugs in subregister handling in peephole-opt. In the common case, it would give up on folding anything into a subregister extract copy.
…lvm#125642) RISCV Zicfilp/Zicfiss extensions uses the `.note.gnu.property` section to store flags indicating the adoption of features based on these extensions. This patch enables the llvm-readobj/llvm-readelf tools to dump these flags with the `--note` flag.
…lues. The getBootstrapMap, getBootstrapMapValue, getBootstrapSymbolsMap, and getBootstrapSymbols methods forward to their respective counterparts in ExecutorProcessControl, similar to the callWrapper functions. These methods will be used to simplify an upcoming patch that accesses the bootstrap values.
…, LLJIT. The system libunwind on older Darwins does not support JIT registration of compact-unwind. Since the CompactUnwindManager utility discards redundant eh-frame FDEs by default we need to remove the compact-unwind section first when targeting older libunwinds in order to preserve eh-frames. While LLJIT was already doing this as of eae6d6d, MachOPlatform was not. This was causing buildbot failures in the ORC runtime (e.g. in https://green.lab.llvm.org/job/llvm.org/job/clang-stage1-RA/3479/). This patch updates both LLJIT and MachOPlatform to check a bootstrap value, "darwin-use-ehframes-only", to determine whether to forcibly preserve eh-frame sections. If this value is present and set to true then compact-unwind sections will be discarded, causing eh-frames to be preserved. If the value is absent or set to false then compact-unwind will be used and redundant FDEs in eh-frames discarded (FDEs that are needed by the compact-unwind section are always preserved). rdar://143895614
The C++ standard prohibits this implicit destructor call, leading to incorrect reports from clang-analyzer. This causes projects that use std::option (including llvm) to fail the cplusplus.NewDelete test incorrectly when run through the analyzer. Fixes llvm#119415
With this patch, we are enabling comparisons for Long double (80) types on X87 stack. It lowers G_FCMP. --------- Co-authored-by: mattarde <[email protected]>
MemProfiler.cpp annotates the IR with the memory profile so that we can later duplicate context. This patch dumps the entire inline call stack for each call site match.
/llvm-project/llvm/lib/Target/X86/GISel/X86InstructionSelector.cpp:1054:9: error: unused variable 'RhsBank' [-Werror,-Wunused-variable] auto *RhsBank = RBI.getRegBank(RhsReg, MRI, TRI); ^ 1 error generated.
…_slice` (2/N) (llvm#123031) For context, recall that `tensor.insert_slice` is vectorised using the `vector.transfer_read` + `vector.transfer_write` pair. An unmasked example is shown below: ```mlir // BEFORE VECTORIZATION %res = tensor.insert_slice %slice into %dest[0, %c2] [5, 1] [1, 1] : tensor<5x1xi32> into tensor<5x3xi32> // AFTER VECTORIZATION %read = vector.transfer_read %source[%c0, %c0], %pad : tensor<5x1xi32>, vector<8x1xi32> %res = vector.transfer_write %read, %dest[%c0, %c2] : vector<8x1xi32>, tensor<5x3xi32> ``` This PR extends `vectorizeAsInsertSliceOp` to add masking support for the `vector.transfer_write` operation. This complements the changes in llvm#122927, which introduced masking for the `vector.transfer_read`.
…o const sized array are not warned (llvm#125483) Add more tests, where the index of the const array access evaluates to a constant and depends on a template argument. rdar://143759014 Co-authored-by: MalavikaSamak <[email protected]>
…ersion (NFC) (llvm#126274) Follow-up to llvm#123569 The obsolete bitcasts on the LoadInsts are also removed.
PR llvm#126091 adds intrinsics for tcgen05 wait/fence/commit operations. This patch adds NVVM Dialect Ops for them. Signed-off-by: Durgadoss R <[email protected]>
… pass (llvm#126325) The TransactionAcceptOrRevert pass is the final pass in the Sandbox Vectorizer's default pass pipeline. It's job is to check the cost before/after vectorization and accept or revert the IR to its original state. Since we are now starting the transaction in BottomUpVec, tests that run a custom pipeline need to accept the transaction. This is done with the help of the TransactionAlwaysAccept pass (tr-accept).
) Following the conclusion of the [RFC](https://discourse.llvm.org/t/rfc-names-for-flang-rt-libraries/84321), rename Flang's runtime libraries as follows: * libFortranRuntime.(a|so) to libflang_rt.runtime.(a|so) * libFortranFloat128Math.a to libflang_rt.quadmath.a * libCufRuntime_cuda_${CUDAToolkit_VERSION_MAJOR}.(a|so) to libflang_rt.cuda_${CUDAToolkit_VERSION_MAJOR}.(a|so) This follows the same naming scheme as Compiler-RT libraries (`libclang_rt.${component}.(a|so)`). It provides some consistency between Flang's runtime libraries for current and potential future library components.
Add test coverage with phis outside a header block with multiple incoming values.
…ession" warning. NFC Fixes llvm#125543
…uous instrumentation profiling mode (llvm#124353) In Continuous instrumentation profiling mode, profile or coverage data collected via compiler instrumentation is continuously synced to the profile file. This feature has existed for a while, and is documented here: https://clang.llvm.org/docs/SourceBasedCodeCoverage.html#running-the-instrumented-program This PR creates a user facing option to enable the feature. --------- Co-authored-by: Wael Yehia <[email protected]>
Recognize the visionOS Triple::OSType::XROS os type. Some of these have already been landed on main, but I reviewed the downstream sources and there were a few that still needed to be landed upstream.
…des. NFC ContractNodes recursively walks forward through a linked list. During this recursion, Matchers are combined into other Matchers. Previously the formation of MoveSiblingMatcher was after the recursive call so it occurred as we were unwinding. If a MoveSiblingMatcher was formed, we would recursively walk forward to the end of the linked list again which isn't efficient. To make this more efficient, move the formation of MoveSiblingMatcher to the forward pass. Add additional rules to unfold MoveSiblingMatcher if it would be more efficient to use CheckChildType, CheckChildInteger, CheckChildSame, etc. As an added benefit, this makes the function tail recursive which the compiler can better optimize.
When an explicit `N` is passed to the loop unroll directive, the unrolling factor should N if N > 1, and unrolling should be disabled when N is 0 or 1. Update docs and add test cases.
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…too. (llvm#132267) Observed in Wine when trying to intercept `ExitThread`, which forwards to `ntdll.RtlExitUserThread`. `gdb` interprets it as `xchg %ax,%ax`. `llvm-mc` outputs simply `nop`. ``` ==Asan-i386-calls-Dynamic-Test.exe==964==interception_win: unhandled instruction at 0x7be27cf0: 66 90 55 89 e5 56 50 8b ``` ``` Wine-gdb> bt #0 0x789a1766 in __interception::GetInstructionSize (address=<optimized out>, rel_offset=<optimized out>) at C:/llvm-mingw/llvm-mingw/llvm-project/compiler-rt/lib/interception/interception_win.cpp:983 #1 0x789ab480 in __sanitizer::SharedPrintfCode(bool, char const*, char*) () at C:/llvm-mingw/llvm-mingw/llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_printf.cpp:311 #2 0x789a18e7 in __interception::OverrideFunctionWithHotPatch (old_func=2078440688, new_func=2023702608, orig_old_func=warning: (Internal error: pc 0x792f1a2c in read in CU, but not in symtab.)warning: (Error: pc 0x792f1a2c in address map, but not in symtab.)0x792f1a2c) at C:/llvm-mingw/llvm-mingw/llvm-project/compiler-rt/lib/interception/interception_win.cpp:1118 #3 0x789a1f34 in __interception::OverrideFunction (old_func=2078440688, new_func=2023702608, orig_old_func=warning: (Internal error: pc 0x792f1a2c in read in CU, but not in symtab.)warning: (Error: pc 0x792f1a2c in address map, but not in symtab.)0x792f1a2c) at C:/llvm-mingw/llvm-mingw/llvm-project/compiler-rt/lib/interception/interception_win.cpp:1224 #4 0x789a24ce in __interception::OverrideFunction (func_name=0x78a0bc43 <vtable for __asan::AsanThreadContext+1163> "ExitThread", new_func=2023702608, orig_old_func=warning: (Internal error: pc 0x792f1a2c in read in CU, but not in symtab.)warning: (Error: pc 0x792f1a2c in address map, but not in symtab.)0x792f1a2c) at C:/llvm-mingw/llvm-mingw/llvm-project/compiler-rt/lib/interception/interception_win.cpp:1369 #5 0x789f40ef in __asan::InitializePlatformInterceptors () at C:/llvm-mingw/llvm-mingw/llvm-project/compiler-rt/lib/asan/asan_win.cpp:190 #6 0x789e0c3c in __asan::InitializeAsanInterceptors () at C:/llvm-mingw/llvm-mingw/llvm-project/compiler-rt/lib/asan/asan_interceptors.cpp:802 #7 0x789ee6b5 in __asan::AsanInitInternal () at C:/llvm-mingw/llvm-mingw/llvm-project/compiler-rt/lib/asan/asan_rtl.cpp:442 #8 0x789eefb0 in __asan::AsanInitFromRtl () at C:/llvm-mingw/llvm-mingw/llvm-project/compiler-rt/lib/asan/asan_rtl.cpp:522 #9 __asan::AsanInitializer::AsanInitializer (this=<optimized out>) at C:/llvm-mingw/llvm-mingw/llvm-project/compiler-rt/lib/asan/asan_rtl.cpp:542 #10 __cxx_global_var_init () at C:/llvm-mingw/llvm-mingw/llvm-project/compiler-rt/lib/asan/asan_rtl.cpp:546 ... Wine-gdb> disassemble /r 2078440688,2078440688+20 Dump of assembler code from 0x7be27cf0 to 0x7be27d04: 0x7be27cf0 <_RtlExitUserThread@4+0>: 66 90 xchg %ax,%ax ... ```
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…ctor-bits=128." (llvm#134997) Reverts llvm#134068 Caused a stage 2 build failure: https://lab.llvm.org/buildbot/#/builders/41/builds/6016 ``` FAILED: lib/Support/CMakeFiles/LLVMSupport.dir/Caching.cpp.o /home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/stage1.install/bin/clang++ -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/stage2/lib/Support -I/home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/llvm/llvm/lib/Support -I/home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/stage2/include -I/home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/llvm/llvm/include -mcpu=neoverse-512tvb -mllvm -scalable-vectorization=preferred -mllvm -treat-scalable-fixed-error-as-warning=false -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -Werror=global-constructors -O3 -DNDEBUG -std=c++17 -UNDEBUG -fno-exceptions -funwind-tables -fno-rtti -MD -MT lib/Support/CMakeFiles/LLVMSupport.dir/Caching.cpp.o -MF lib/Support/CMakeFiles/LLVMSupport.dir/Caching.cpp.o.d -o lib/Support/CMakeFiles/LLVMSupport.dir/Caching.cpp.o -c /home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/llvm/llvm/lib/Support/Caching.cpp Opcode has unknown scale! UNREACHABLE executed at ../llvm/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp:4530! PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script. Stack dump: 0. Program arguments: /home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/stage1.install/bin/clang++ -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/stage2/lib/Support -I/home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/llvm/llvm/lib/Support -I/home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/stage2/include -I/home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/llvm/llvm/include -mcpu=neoverse-512tvb -mllvm -scalable-vectorization=preferred -mllvm -treat-scalable-fixed-error-as-warning=false -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -Werror=global-constructors -O3 -DNDEBUG -std=c++17 -UNDEBUG -fno-exceptions -funwind-tables -fno-rtti -MD -MT lib/Support/CMakeFiles/LLVMSupport.dir/Caching.cpp.o -MF lib/Support/CMakeFiles/LLVMSupport.dir/Caching.cpp.o.d -o lib/Support/CMakeFiles/LLVMSupport.dir/Caching.cpp.o -c /home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/llvm/llvm/lib/Support/Caching.cpp 1. <eof> parser at end of file 2. Code generation 3. Running pass 'Function Pass Manager' on module '/home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/llvm/llvm/lib/Support/Caching.cpp'. 4. Running pass 'AArch64 load / store optimization pass' on function '@"_ZNSt17_Function_handlerIFN4llvm8ExpectedISt8functionIFNS1_ISt10unique_ptrINS0_16CachedFileStreamESt14default_deleteIS4_EEEEjRKNS0_5TwineEEEEEjNS0_9StringRefESB_EZNS0_10localCacheESB_SB_SB_S2_IFvjSB_S3_INS0_12MemoryBufferES5_ISH_EEEEE3$_0E9_M_invokeERKSt9_Any_dataOjOSF_SB_"' #0 0x0000b6eae9b67bf0 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/stage1.install/bin/clang+++0x81c7bf0) #1 0x0000b6eae9b65aec llvm::sys::RunSignalHandlers() (/home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/stage1.install/bin/clang+++0x81c5aec) #2 0x0000b6eae9acd5f4 CrashRecoverySignalHandler(int) CrashRecoveryContext.cpp:0:0 #3 0x0000f16c1aff28f8 (linux-vdso.so.1+0x8f8) #4 0x0000f16c1aacf1f0 __pthread_kill_implementation ./nptl/pthread_kill.c:44:76 #5 0x0000f16c1aa8a67c gsignal ./signal/../sysdeps/posix/raise.c:27:6 #6 0x0000f16c1aa77130 abort ./stdlib/abort.c:81:7 #7 0x0000b6eae9ad6628 (/home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/stage1.install/bin/clang+++0x8136628) #8 0x0000b6eae72e95a8 (/home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/stage1.install/bin/clang+++0x59495a8) #9 0x0000b6eae74ca9a8 (anonymous namespace)::AArch64LoadStoreOpt::findMatchingInsn(llvm::MachineInstrBundleIterator<llvm::MachineInstr, false>, (anonymous namespace)::LdStPairFlags&, unsigned int, bool) AArch64LoadStoreOptimizer.cpp:0:0 #10 0x0000b6eae74c85a8 (anonymous namespace)::AArch64LoadStoreOpt::tryToPairLdStInst(llvm::MachineInstrBundleIterator<llvm::MachineInstr, false>&) AArch64LoadStoreOptimizer.cpp:0:0 llvm#11 0x0000b6eae74c624c (anonymous namespace)::AArch64LoadStoreOpt::optimizeBlock(llvm::MachineBasicBlock&, bool) AArch64LoadStoreOptimizer.cpp:0:0 llvm#12 0x0000b6eae74c429c (anonymous namespace)::AArch64LoadStoreOpt::runOnMachineFunction(llvm::MachineFunction&) AArch64LoadStoreOptimizer.cpp:0:0 ```
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…reporting (llvm#131756) ### Description This PR resolves a deadlock between AddressSanitizer (ASan) and LeakSanitizer (LSan) that occurs when both sanitizers attempt to acquire locks in conflicting orders across threads. The fix ensures safe lock acquisition ordering by preloading module information before error reporting. --- ### Issue Details **Reproducer** ```cpp // Thread 1: ASan error path int arr[1] = {0}; std::thread t([&]() { arr[1] = 1; // Triggers ASan OOB error }); // Thread 2: LSan check path __lsan_do_leak_check(); ``` **Lock Order Conflict**: - Thread 1 (ASan error reporting): 1. Acquires ASan thread registry lock (B) 1. Attempts to acquire libdl lock (A) via `dl_iterate_phdr` - Thread 2 (LSan leak check): 1. Acquires libdl lock (A) via `dl_iterate_phdr` 1. Attempts to acquire ASan thread registry lock (B) This creates a circular wait condition (A -> B -> A) meeting all four Coffman deadlock criteria. --- ### Fix Strategy The root cause lies in ASan's error reporting path needing `dl_iterate_phdr` (requiring lock A) while already holding its thread registry lock (B). The solution: 1. **Preload Modules Early**: Force module list initialization _before_ acquiring ASan's thread lock 2. **Avoid Nested Locking**: Ensure symbolization (via dl_iterate_phdr) completes before error reporting locks Key code change: ```cpp // Before acquiring ASan's thread registry lock: Symbolizer::GetOrInit()->GetRefreshedListOfModules(); ``` This guarantees module information is cached before lock acquisition, eliminating the need for `dl_iterate_phdr` calls during error reporting. --- ### Testing Added **asan_lsan_deadlock.cpp** test case: - Reproduces deadlock reliably without fix **under idle system conditions** - Uses watchdog thread to detect hangs - Verifies ASan error reports correctly without deadlock **Note**: Due to the inherent non-determinism of thread scheduling and lock acquisition timing, this test may not reliably reproduce the deadlock on busy systems (e.g., during parallel `ninja check-asan` runs). --- ### Impact - Fixes rare but severe deadlocks in mixed ASan+LSan environments - Maintains thread safety guarantees for both sanitizers - No user-visible behavior changes except deadlock elimination --- ### Relevant Buggy Code - Code in ASan's asan_report.cpp ```cpp explicit ScopedInErrorReport(bool fatal = false) : halt_on_error_(fatal || flags()->halt_on_error) { // Acquire lock B asanThreadRegistry().Lock(); } ~ScopedInErrorReport() { ... // Try to acquire lock A under holding lock B via the following path // #4 0x000071a353d83e93 in __GI___dl_iterate_phdr ( // callback=0x5d1a07a39580 <__sanitizer::dl_iterate_phdr_cb(dl_phdr_info*, unsigned long, void*)>, // data=0x6da3510fd3f0) at ./elf/dl-iteratephdr.c:39 // #5 0x00005d1a07a39574 in __sanitizer::ListOfModules::init (this=0x71a353ebc080) // at llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp:784 // #6 0x00005d1a07a429e3 in __sanitizer::Symbolizer::RefreshModules (this=0x71a353ebc058) // at llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_libcdep.cpp:188 // #7 __sanitizer::Symbolizer::FindModuleForAddress (this=this@entry=0x71a353ebc058, // address=address@entry=102366378805727) // at llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_libcdep.cpp:214 // #8 0x00005d1a07a4291b in __sanitizer::Symbolizer::SymbolizePC (this=0x71a353ebc058, addr=102366378805727) // at llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_libcdep.cpp:88 // #9 0x00005d1a07a40df7 in __sanitizer::(anonymous namespace)::StackTraceTextPrinter::ProcessAddressFrames ( // this=this@entry=0x6da3510fd520, pc=102366378805727) // at llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace_libcdep.cpp:37 // #10 0x00005d1a07a40d27 in __sanitizer::StackTrace::PrintTo (this=this@entry=0x6da3510fd5e8, // output=output@entry=0x6da3510fd588) // at llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace_libcdep.cpp:110 // llvm#11 0x00005d1a07a410a1 in __sanitizer::StackTrace::Print (this=0x6da3510fd5e8) // at llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace_libcdep.cpp:133 // llvm#12 0x00005d1a0798758d in __asan::ErrorGeneric::Print ( // this=0x5d1a07aa4e08 <__asan::ScopedInErrorReport::current_error_+8>) // at llvm-project/compiler-rt/lib/asan/asan_errors.cpp:617 current_error_.Print(); ... } ``` - Code in LSan's lsan_common_linux.cpp ```cpp void LockStuffAndStopTheWorld(StopTheWorldCallback callback, CheckForLeaksParam *argument) { // Acquire lock A dl_iterate_phdr(LockStuffAndStopTheWorldCallback, ¶m); } static int LockStuffAndStopTheWorldCallback(struct dl_phdr_info *info, size_t size, void *data) { // Try to acquire lock B under holding lock A via the following path // #3 0x000055555562b34a in __sanitizer::ThreadRegistry::Lock (this=<optimized out>) // at llvm-project/compiler-rt/lib/asan/../sanitizer_common/sanitizer_thread_registry.h:99 // #4 __lsan::LockThreads () at llvm-project/compiler-rt/lib/asan/asan_thread.cpp:484 // #5 0x0000555555652629 in __lsan::ScopedStopTheWorldLock::ScopedStopTheWorldLock (this=<optimized out>) // at llvm-project/compiler-rt/lib/lsan/lsan_common.h:164 // #6 __lsan::LockStuffAndStopTheWorldCallback (info=<optimized out>, size=<optimized out>, data=0x0, // data@entry=0x7fffffffd158) at llvm-project/compiler-rt/lib/lsan/lsan_common_linux.cpp:120 ScopedStopTheWorldLock lock; DoStopTheWorldParam *param = reinterpret_cast<DoStopTheWorldParam *>(data); StopTheWorld(param->callback, param->argument); return 1; } ```
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… collection (llvm#136795) Fix a [test failure](llvm#136236 (comment)) in llvm#136236, apply a minor renaming of statistics, and remerge. See details below. # Changes in llvm#136236 Currently, `DebuggerStats::ReportStatistics()` calls `Module::GetSymtab(/*can_create=*/false)`, but then the latter calls `SymbolFile::GetSymtab()`. This will load symbols if haven't yet. See stacktrace below. The problem is that `DebuggerStats::ReportStatistics` should be read-only. This is especially important because it reports stats for symtab parsing/indexing time, which could be affected by the reporting itself if it's not read-only. This patch fixes this problem by adding an optional parameter `SymbolFile::GetSymtab(bool can_create = true)` and receiving the `false` value passed down from `Module::GetSymtab(/*can_create=*/false)` when the call is initiated from `DebuggerStats::ReportStatistics()`. --- Notes about the following stacktrace: 1. This can be reproduced. Create a helloworld program on **macOS** with dSYM, add `settings set target.preload-symbols false` to `~/.lldbinit`, do `lldb a.out`, then `statistics dump`. 2. `ObjectFile::GetSymtab` has `llvm::call_once`. So the fact that it called into `ObjectFileMachO::ParseSymtab` means that the symbol table is actually being parsed. ``` (lldb) bt * thread #1, queue = 'com.apple.main-thread', stop reason = step over frame #0: 0x0000000124c4d5a0 LLDB`ObjectFileMachO::ParseSymtab(this=0x0000000111504e40, symtab=0x0000600000a05e00) at ObjectFileMachO.cpp:2259:44 * frame #1: 0x0000000124fc50a0 LLDB`lldb_private::ObjectFile::GetSymtab()::$_0::operator()(this=0x000000016d35c858) const at ObjectFile.cpp:761:9 frame #5: 0x0000000124fc4e68 LLDB`void std::__1::__call_once_proxy[abi:v160006]<std::__1::tuple<lldb_private::ObjectFile::GetSymtab()::$_0&&>>(__vp=0x000000016d35c7f0) at mutex:652:5 frame #6: 0x0000000198afb99c libc++.1.dylib`std::__1::__call_once(unsigned long volatile&, void*, void (*)(void*)) + 196 frame #7: 0x0000000124fc4dd0 LLDB`void std::__1::call_once[abi:v160006]<lldb_private::ObjectFile::GetSymtab()::$_0>(__flag=0x0000600003920080, __func=0x000000016d35c858) at mutex:670:9 frame #8: 0x0000000124fc3cb0 LLDB`void llvm::call_once<lldb_private::ObjectFile::GetSymtab()::$_0>(flag=0x0000600003920080, F=0x000000016d35c858) at Threading.h:88:5 frame #9: 0x0000000124fc2bc4 LLDB`lldb_private::ObjectFile::GetSymtab(this=0x0000000111504e40) at ObjectFile.cpp:755:5 frame #10: 0x0000000124fe0a28 LLDB`lldb_private::SymbolFileCommon::GetSymtab(this=0x0000000104865200) at SymbolFile.cpp:158:39 frame llvm#11: 0x0000000124d8fedc LLDB`lldb_private::Module::GetSymtab(this=0x00000001113041a8, can_create=false) at Module.cpp:1027:21 frame llvm#12: 0x0000000125125bdc LLDB`lldb_private::DebuggerStats::ReportStatistics(debugger=0x000000014284d400, target=0x0000000115808200, options=0x000000014195d6d1) at Statistics.cpp:329:30 frame llvm#13: 0x0000000125672978 LLDB`CommandObjectStatsDump::DoExecute(this=0x000000014195d540, command=0x000000016d35d820, result=0x000000016d35e150) at CommandObjectStats.cpp:144:18 frame llvm#14: 0x0000000124f29b40 LLDB`lldb_private::CommandObjectParsed::Execute(this=0x000000014195d540, args_string="", result=0x000000016d35e150) at CommandObject.cpp:832:9 frame llvm#15: 0x0000000124efbd70 LLDB`lldb_private::CommandInterpreter::HandleCommand(this=0x0000000141b22f30, command_line="statistics dump", lazy_add_to_history=eLazyBoolCalculate, result=0x000000016d35e150, force_repeat_command=false) at CommandInterpreter.cpp:2134:14 frame llvm#16: 0x0000000124f007f4 LLDB`lldb_private::CommandInterpreter::IOHandlerInputComplete(this=0x0000000141b22f30, io_handler=0x00000001419b2aa8, line="statistics dump") at CommandInterpreter.cpp:3251:3 frame llvm#17: 0x0000000124d7b5ec LLDB`lldb_private::IOHandlerEditline::Run(this=0x00000001419b2aa8) at IOHandler.cpp:588:22 frame llvm#18: 0x0000000124d1e8fc LLDB`lldb_private::Debugger::RunIOHandlers(this=0x000000014284d400) at Debugger.cpp:1225:16 frame llvm#19: 0x0000000124f01f74 LLDB`lldb_private::CommandInterpreter::RunCommandInterpreter(this=0x0000000141b22f30, options=0x000000016d35e63c) at CommandInterpreter.cpp:3543:16 frame llvm#20: 0x0000000122840294 LLDB`lldb::SBDebugger::RunCommandInterpreter(this=0x000000016d35ebd8, auto_handle_events=true, spawn_thread=false) at SBDebugger.cpp:1212:42 frame llvm#21: 0x0000000102aa6d28 lldb`Driver::MainLoop(this=0x000000016d35ebb8) at Driver.cpp:621:18 frame llvm#22: 0x0000000102aa75b0 lldb`main(argc=1, argv=0x000000016d35f548) at Driver.cpp:829:26 frame llvm#23: 0x0000000198858274 dyld`start + 2840 ``` # Changes in this PR top of the above Fix a [test failure](llvm#136236 (comment)) in `TestStats.py`. The original version of the added test checks that all modules have symbol count zero when `target.preload-symbols == false`. The test failed on macOS. Due to various reasons, on macOS, symbols can be loaded for dylibs even with that setting, but not for the main module. For now, the fix of the test is to limit the assertion to only the main module. The test now passes on macOS. In the future, when we have a way to control a specific list of plug-ins to be loaded, there may be a configuration that this test can use to assert that all modules have symbol count zero. Apply a minor renaming of statistics, per the [suggestion](llvm#136226 (comment)) in llvm#136226 after merge.
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…mbolConjured" (llvm#137304) Reverts llvm#128251 ASAN bots reported some errors: https://lab.llvm.org/buildbot/#/builders/55/builds/10398 Reverting for investigation. ``` Failed Tests (6): Clang :: Analysis/loop-widening-ignore-static-methods.cpp Clang :: Analysis/loop-widening-notes.cpp Clang :: Analysis/loop-widening-preserve-reference-type.cpp Clang :: Analysis/loop-widening.c Clang :: Analysis/loop-widening.cpp Clang :: Analysis/this-pointer.cpp Testing Time: 411.55s Total Discovered Tests: 118563 Skipped : 33 (0.03%) Unsupported : 2015 (1.70%) Passed : 116291 (98.08%) Expectedly Failed: 218 (0.18%) Failed : 6 (0.01%) FAILED: CMakeFiles/check-all /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/CMakeFiles/check-all cd /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan && /usr/bin/python3 /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/./bin/llvm-lit -sv --param USE_Z3_SOLVER=0 /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/utils/mlgo-utils /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/tools/lld/test /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/tools/mlir/test /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/tools/clang/test /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/utils/lit /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/test ninja: build stopped: subcommand failed. ``` ``` /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/bin/clang -cc1 -internal-isystem /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/lib/clang/21/include -nostdsysteminc -analyze -analyzer-constraints=range -setup-static-analyzer -analyzer-checker=core,unix.Malloc,debug.ExprInspection -analyzer-max-loop 4 -analyzer-config widen-loops=true -verify -analyzer-config eagerly-assume=false /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/test/Analysis/loop-widening.c # RUN: at line 1 + /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/bin/clang -cc1 -internal-isystem /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/lib/clang/21/include -nostdsysteminc -analyze -analyzer-constraints=range -setup-static-analyzer -analyzer-checker=core,unix.Malloc,debug.ExprInspection -analyzer-max-loop 4 -analyzer-config widen-loops=true -verify -analyzer-config eagerly-assume=false /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/test/Analysis/loop-widening.c PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script. Stack dump: 0. Program arguments: /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/bin/clang -cc1 -internal-isystem /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/lib/clang/21/include -nostdsysteminc -analyze -analyzer-constraints=range -setup-static-analyzer -analyzer-checker=core,unix.Malloc,debug.ExprInspection -analyzer-max-loop 4 -analyzer-config widen-loops=true -verify -analyzer-config eagerly-assume=false /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/test/Analysis/loop-widening.c 1. <eof> parser at end of file 2. While analyzing stack: #0 Calling nested_loop_inner_widen #0 0x0000c894cca289cc llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/llvm/lib/Support/Unix/Signals.inc:804:13 #1 0x0000c894cca23324 llvm::sys::RunSignalHandlers() /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/llvm/lib/Support/Signals.cpp:106:18 #2 0x0000c894cca29bbc SignalHandler(int, siginfo_t*, void*) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/llvm/lib/Support/Unix/Signals.inc:0:3 #3 0x0000f6898da4a8f8 (linux-vdso.so.1+0x8f8) #4 0x0000f6898d377608 (/lib/aarch64-linux-gnu/libc.so.6+0x87608) #5 0x0000f6898d32cb3c raise (/lib/aarch64-linux-gnu/libc.so.6+0x3cb3c) #6 0x0000f6898d317e00 abort (/lib/aarch64-linux-gnu/libc.so.6+0x27e00) #7 0x0000c894c5e77fec __sanitizer::Atexit(void (*)()) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_posix_libcdep.cpp:168:10 #8 0x0000c894c5e76680 __sanitizer::Die() /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_termination.cpp:52:5 #9 0x0000c894c5e69650 Unlock /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/hwasan/../sanitizer_common/sanitizer_mutex.h:250:16 #10 0x0000c894c5e69650 ~GenericScopedLock /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/hwasan/../sanitizer_common/sanitizer_mutex.h:386:51 llvm#11 0x0000c894c5e69650 __hwasan::ScopedReport::~ScopedReport() /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/hwasan/hwasan_report.cpp:54:5 llvm#12 0x0000c894c5e68de0 __hwasan::(anonymous namespace)::BaseReport::~BaseReport() /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/hwasan/hwasan_report.cpp:476:7 llvm#13 0x0000c894c5e66b74 __hwasan::ReportTagMismatch(__sanitizer::StackTrace*, unsigned long, unsigned long, bool, bool, unsigned long*) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/hwasan/hwasan_report.cpp:1091:1 llvm#14 0x0000c894c5e52cf8 Destroy /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/hwasan/../sanitizer_common/sanitizer_common.h:532:31 llvm#15 0x0000c894c5e52cf8 ~InternalMmapVector /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/hwasan/../sanitizer_common/sanitizer_common.h:642:56 llvm#16 0x0000c894c5e52cf8 __hwasan::HandleTagMismatch(__hwasan::AccessInfo, unsigned long, unsigned long, void*, unsigned long*) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/hwasan/hwasan.cpp:245:1 llvm#17 0x0000c894c5e551c8 __hwasan_tag_mismatch4 /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/hwasan/hwasan.cpp:764:1 llvm#18 0x0000c894c5e6a2f8 __interception::InterceptFunction(char const*, unsigned long*, unsigned long, unsigned long) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/interception/interception_linux.cpp:60:0 llvm#19 0x0000c894d166f664 getBlock /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/include/clang/StaticAnalyzer/Core/PathSensitive/CoreEngine.h:217:45 llvm#20 0x0000c894d166f664 getCFGElementRef /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/include/clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h:230:59 llvm#21 0x0000c894d166f664 clang::ento::ExprEngine::processCFGBlockEntrance(clang::BlockEdge const&, clang::ento::NodeBuilderWithSinks&, clang::ento::ExplodedNode*) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/lib/StaticAnalyzer/Core/ExprEngine.cpp:2570:45 llvm#22 0x0000c894d15f3a1c hasGeneratedNodes /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/include/clang/StaticAnalyzer/Core/PathSensitive/CoreEngine.h:333:37 llvm#23 0x0000c894d15f3a1c clang::ento::CoreEngine::HandleBlockEdge(clang::BlockEdge const&, clang::ento::ExplodedNode*) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/lib/StaticAnalyzer/Core/CoreEngine.cpp:319:20 llvm#24 0x0000c894d15f2c34 clang::ento::CoreEngine::dispatchWorkItem(clang::ento::ExplodedNode*, clang::ProgramPoint, clang::ento::WorkListUnit const&) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/lib/StaticAnalyzer/Core/CoreEngine.cpp:220:7 llvm#25 0x0000c894d15f2398 operator-> /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/libcxx_install_hwasan/include/c++/v1/__memory/unique_ptr.h:267:101 llvm#26 0x0000c894d15f2398 clang::ento::CoreEngine::ExecuteWorkList(clang::LocationContext const*, unsigned int, llvm::IntrusiveRefCntPtr<clang::ento::ProgramState const>)::$_0::operator()(unsigned int) const /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/lib/StaticAnalyzer/Core/CoreEngine.cpp:140:12 llvm#27 0x0000c894d15f14b4 clang::ento::CoreEngine::ExecuteWorkList(clang::LocationContext const*, unsigned int, llvm::IntrusiveRefCntPtr<clang::ento::ProgramState const>) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/lib/StaticAnalyzer/Core/CoreEngine.cpp:165:7 llvm#28 0x0000c894d0ebb9dc release /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/llvm/include/llvm/ADT/IntrusiveRefCntPtr.h:232:9 llvm#29 0x0000c894d0ebb9dc ~IntrusiveRefCntPtr /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/llvm/include/llvm/ADT/IntrusiveRefCntPtr.h:196:27 llvm#30 0x0000c894d0ebb9dc ExecuteWorkList /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/include/clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h:192:5 llvm#31 0x0000c894d0ebb9dc RunPathSensitiveChecks /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp:772:7 llvm#32 0x0000c894d0ebb9dc (anonymous namespace)::AnalysisConsumer::HandleCode(clang::Decl*, unsigned int, clang::ento::ExprEngine::InliningModes, llvm::DenseSet<clang::Decl const*, llvm::DenseMapInfo<clang::Decl const*, void>>*) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp:741:5 llvm#33 0x0000c894d0eb6ee4 begin /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/llvm/include/llvm/ADT/DenseMap.h:0:0 llvm#34 0x0000c894d0eb6ee4 begin /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/llvm/include/llvm/ADT/DenseSet.h:187:45 llvm#35 0x0000c894d0eb6ee4 HandleDeclsCallGraph /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp:516:29 llvm#36 0x0000c894d0eb6ee4 runAnalysisOnTranslationUnit /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp:584:5 llvm#37 0x0000c894d0eb6ee4 (anonymous namespace)::AnalysisConsumer::HandleTranslationUnit(clang::ASTContext&) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp:647:3 llvm#38 0x0000c894d18a7a38 clang::ParseAST(clang::Sema&, bool, bool) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/lib/Parse/ParseAST.cpp:0:13 llvm#39 0x0000c894ce81ed70 clang::FrontendAction::Execute() /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/lib/Frontend/FrontendAction.cpp:1231:10 llvm#40 0x0000c894ce6f2144 getPtr /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/llvm/include/llvm/Support/Error.h:278:42 llvm#41 0x0000c894ce6f2144 operator bool /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/llvm/include/llvm/Support/Error.h:241:16 llvm#42 0x0000c894ce6f2144 clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/lib/Frontend/CompilerInstance.cpp:1058:23 llvm#43 0x0000c894cea718cc operator-> /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/libcxx_install_hwasan/include/c++/v1/__memory/shared_ptr.h:635:12 llvm#44 0x0000c894cea718cc getFrontendOpts /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/include/clang/Frontend/CompilerInstance.h:307:12 llvm#45 0x0000c894cea718cc clang::ExecuteCompilerInvocation(clang::CompilerInstance*) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/lib/FrontendTool/ExecuteCompilerInvocation.cpp:301:14 llvm#46 0x0000c894c5e9cf28 cc1_main(llvm::ArrayRef<char const*>, char const*, void*) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/tools/driver/cc1_main.cpp:294:15 llvm#47 0x0000c894c5e92a9c ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/tools/driver/driver.cpp:223:12 llvm#48 0x0000c894c5e902ac clang_main(int, char**, llvm::ToolContext const&) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/tools/driver/driver.cpp:0:12 llvm#49 0x0000c894c5eb2e34 main /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/tools/clang/tools/driver/clang-driver.cpp:17:3 llvm#50 0x0000f6898d3184c4 (/lib/aarch64-linux-gnu/libc.so.6+0x284c4) llvm#51 0x0000f6898d318598 __libc_start_main (/lib/aarch64-linux-gnu/libc.so.6+0x28598) llvm#52 0x0000c894c5e52a30 _start (/home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/bin/clang+0x6512a30) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/tools/clang/test/Analysis/Output/loop-widening.c.script: line 2: 2870204 Aborted /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/bin/clang -cc1 -internal-isystem /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/lib/clang/21/include -nostdsysteminc -analyze -analyzer-constraints=range -setup-static-analyzer -analyzer-checker=core,unix.Malloc,debug.ExprInspection -analyzer-max-loop 4 -analyzer-config widen-loops=true -verify -analyzer-config eagerly-assume=false /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/clang/test/Analysis/loop-widening.c ```
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`clang-repl --cuda` was previously crashing with a segmentation fault, instead of reporting a clean error ``` (base) anutosh491@Anutoshs-MacBook-Air bin % ./clang-repl --cuda #0 0x0000000111da4fbc llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/local/libexec/llvm-20/lib/libLLVM.dylib+0x150fbc) #1 0x0000000111da31dc llvm::sys::RunSignalHandlers() (/opt/local/libexec/llvm-20/lib/libLLVM.dylib+0x14f1dc) #2 0x0000000111da5628 SignalHandler(int) (/opt/local/libexec/llvm-20/lib/libLLVM.dylib+0x151628) #3 0x000000019b242de4 (/usr/lib/system/libsystem_platform.dylib+0x180482de4) #4 0x0000000107f638d0 clang::IncrementalCUDADeviceParser::IncrementalCUDADeviceParser(std::__1::unique_ptr<clang::CompilerInstance, std::__1::default_delete<clang::CompilerInstance>>, clang::CompilerInstance&, llvm::IntrusiveRefCntPtr<llvm::vfs::InMemoryFileSystem>, llvm::Error&, std::__1::list<clang::PartialTranslationUnit, std::__1::allocator<clang::PartialTranslationUnit>> const&) (/opt/local/libexec/llvm-20/lib/libclang-cpp.dylib+0x216b8d0) #5 0x0000000107f638d0 clang::IncrementalCUDADeviceParser::IncrementalCUDADeviceParser(std::__1::unique_ptr<clang::CompilerInstance, std::__1::default_delete<clang::CompilerInstance>>, clang::CompilerInstance&, llvm::IntrusiveRefCntPtr<llvm::vfs::InMemoryFileSystem>, llvm::Error&, std::__1::list<clang::PartialTranslationUnit, std::__1::allocator<clang::PartialTranslationUnit>> const&) (/opt/local/libexec/llvm-20/lib/libclang-cpp.dylib+0x216b8d0) #6 0x0000000107f6bac8 clang::Interpreter::createWithCUDA(std::__1::unique_ptr<clang::CompilerInstance, std::__1::default_delete<clang::CompilerInstance>>, std::__1::unique_ptr<clang::CompilerInstance, std::__1::default_delete<clang::CompilerInstance>>) (/opt/local/libexec/llvm-20/lib/libclang-cpp.dylib+0x2173ac8) #7 0x000000010206f8a8 main (/opt/local/libexec/llvm-20/bin/clang-repl+0x1000038a8) #8 0x000000019ae8c274 Segmentation fault: 11 ``` The underlying issue was that the `DeviceCompilerInstance` (used for device-side CUDA compilation) was never initialized with a `Sema`, which is required before constructing the `IncrementalCUDADeviceParser`. https://github.com/llvm/llvm-project/blob/89687e6f383b742a3c6542dc673a84d9f82d02de/clang/lib/Interpreter/DeviceOffload.cpp#L32 https://github.com/llvm/llvm-project/blob/89687e6f383b742a3c6542dc673a84d9f82d02de/clang/lib/Interpreter/IncrementalParser.cpp#L31 Unlike the host-side `CompilerInstance` which runs `ExecuteAction` inside the Interpreter constructor (thereby setting up Sema), the device-side CI was passed into the parser uninitialized, leading to an assertion or crash when accessing its internals. To fix this, I refactored the `Interpreter::create` method to include an optional `DeviceCI` parameter. If provided, we know we need to take care of this instance too. Only then do we construct the `IncrementalCUDADeviceParser`.
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llvm#138091) Check this error for more context (https://github.com/compiler-research/CppInterOp/actions/runs/14749797085/job/41407625681?pr=491#step:10:531) This fails with ``` * thread #1, name = 'CppInterOpTests', stop reason = signal SIGSEGV: address not mapped to object (fault address: 0x55500356d6d3) * frame #0: 0x00007fffee41cfe3 libclangCppInterOp.so.21.0gitclang::PragmaNamespace::~PragmaNamespace() + 99 frame #1: 0x00007fffee435666 libclangCppInterOp.so.21.0gitclang::Preprocessor::~Preprocessor() + 3830 frame #2: 0x00007fffee20917a libclangCppInterOp.so.21.0gitstd::_Sp_counted_base<(__gnu_cxx::_Lock_policy)2>::_M_release() + 58 frame #3: 0x00007fffee224796 libclangCppInterOp.so.21.0gitclang::CompilerInstance::~CompilerInstance() + 838 frame #4: 0x00007fffee22494d libclangCppInterOp.so.21.0gitclang::CompilerInstance::~CompilerInstance() + 13 frame #5: 0x00007fffed95ec62 libclangCppInterOp.so.21.0gitclang::IncrementalCUDADeviceParser::~IncrementalCUDADeviceParser() + 98 frame #6: 0x00007fffed9551b6 libclangCppInterOp.so.21.0gitclang::Interpreter::~Interpreter() + 102 frame #7: 0x00007fffed95598d libclangCppInterOp.so.21.0gitclang::Interpreter::~Interpreter() + 13 frame #8: 0x00007fffed9181e7 libclangCppInterOp.so.21.0gitcompat::createClangInterpreter(std::vector<char const*, std::allocator<char const*>>&) + 2919 ``` Problem : 1) The destructor currently handles no clearance for the DeviceParser and the DeviceAct. We currently only have this https://github.com/llvm/llvm-project/blob/976493822443c52a71ed3c67aaca9a555b20c55d/clang/lib/Interpreter/Interpreter.cpp#L416-L419 2) The ownership for DeviceCI currently is present in IncrementalCudaDeviceParser. But this should be similar to how the combination for hostCI, hostAction and hostParser are managed by the Interpreter. As on master the DeviceAct and DeviceParser are managed by the Interpreter but not DeviceCI. This is problematic because : IncrementalParser holds a Sema& which points into the DeviceCI. On master, DeviceCI is destroyed before the base class ~IncrementalParser() runs, causing Parser::reset() to access a dangling Sema (and as Sema holds a reference to Preprocessor which owns PragmaNamespace) we see this ``` * frame #0: 0x00007fffee41cfe3 libclangCppInterOp.so.21.0gitclang::PragmaNamespace::~PragmaNamespace() + 99 frame #1: 0x00007fffee435666 libclangCppInterOp.so.21.0gitclang::Preprocessor::~Preprocessor() + 3830 ```
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May 9, 2025
The mcmodel=tiny memory model is only valid on ARM targets. While trying this on X86 compiler throws an internal error along with stack dump. llvm#125641 This patch resolves the issue. Reduced test case: ``` #include <stdio.h> int main( void ) { printf( "Hello, World!\n" ); return 0; } ``` ``` 0. Program arguments: /opt/compiler-explorer/clang-trunk/bin/clang++ -gdwarf-4 -g -o /app/output.s -fno-verbose-asm -S --gcc-toolchain=/opt/compiler-explorer/gcc-snapshot -fcolor-diagnostics -fno-crash-diagnostics -mcmodel=tiny <source> 1. <eof> parser at end of file #0 0x0000000003b10218 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3b10218) #1 0x0000000003b0e35c llvm::sys::CleanupOnSignal(unsigned long) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3b0e35c) #2 0x0000000003a5dbc3 llvm::CrashRecoveryContext::HandleExit(int) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3a5dbc3) #3 0x0000000003b05cfe llvm::sys::Process::Exit(int, bool) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3b05cfe) #4 0x0000000000d4e3eb LLVMErrorHandler(void*, char const*, bool) cc1_main.cpp:0:0 #5 0x0000000003a67c93 llvm::report_fatal_error(llvm::Twine const&, bool) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3a67c93) #6 0x0000000003a67df8 (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3a67df8) #7 0x0000000002549148 llvm::X86TargetMachine::X86TargetMachine(llvm::Target const&, llvm::Triple const&, llvm::StringRef, llvm::StringRef, llvm::TargetOptions const&, std::optional<llvm::Reloc::Model>, std::optional<llvm::CodeModel::Model>, llvm::CodeGenOptLevel, bool) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x2549148) #8 0x00000000025491fc llvm::RegisterTargetMachine<llvm::X86TargetMachine>::Allocator(llvm::Target const&, llvm::Triple const&, llvm::StringRef, llvm::StringRef, llvm::TargetOptions const&, std::optional<llvm::Reloc::Model>, std::optional<llvm::CodeModel::Model>, llvm::CodeGenOptLevel, bool) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x25491fc) #9 0x0000000003db74cc clang::emitBackendOutput(clang::CompilerInstance&, clang::CodeGenOptions&, llvm::StringRef, llvm::Module*, clang::BackendAction, llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem>, std::unique_ptr<llvm::raw_pwrite_stream, std::default_delete<llvm::raw_pwrite_stream>>, clang::BackendConsumer*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3db74cc) #10 0x0000000004460d95 clang::BackendConsumer::HandleTranslationUnit(clang::ASTContext&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x4460d95) llvm#11 0x00000000060005ec clang::ParseAST(clang::Sema&, bool, bool) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x60005ec) llvm#12 0x00000000044614b5 clang::CodeGenAction::ExecuteAction() (/opt/compiler-explorer/clang-trunk/bin/clang+++0x44614b5) llvm#13 0x0000000004737121 clang::FrontendAction::Execute() (/opt/compiler-explorer/clang-trunk/bin/clang+++0x4737121) llvm#14 0x00000000046b777b clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x46b777b) llvm#15 0x00000000048229e3 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x48229e3) llvm#16 0x0000000000d50621 cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0xd50621) llvm#17 0x0000000000d48e2d ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&) driver.cpp:0:0 llvm#18 0x00000000044acc99 void llvm::function_ref<void ()>::callback_fn<clang::driver::CC1Command::Execute(llvm::ArrayRef<std::optional<llvm::StringRef>>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const::'lambda'()>(long) Job.cpp:0:0 llvm#19 0x0000000003a5dac3 llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3a5dac3) llvm#20 0x00000000044aceb9 clang::driver::CC1Command::Execute(llvm::ArrayRef<std::optional<llvm::StringRef>>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const (.part.0) Job.cpp:0:0 llvm#21 0x00000000044710dd clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const (/opt/compiler-explorer/clang-trunk/bin/clang+++0x44710dd) llvm#22 0x0000000004472071 clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&, bool) const (/opt/compiler-explorer/clang-trunk/bin/clang+++0x4472071) llvm#23 0x000000000447c3fc clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x447c3fc) llvm#24 0x0000000000d4d2b1 clang_main(int, char**, llvm::ToolContext const&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0xd4d2b1) llvm#25 0x0000000000c12464 main (/opt/compiler-explorer/clang-trunk/bin/clang+++0xc12464) llvm#26 0x00007ae43b029d90 (/lib/x86_64-linux-gnu/libc.so.6+0x29d90) llvm#27 0x00007ae43b029e40 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e40) llvm#28 0x0000000000d488c5 _start (/opt/compiler-explorer/clang-trunk/bin/clang+++0xd488c5) ``` --------- Co-authored-by: Shashwathi N <[email protected]>
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Jun 2, 2025
Fixes llvm#123300 What is seen ``` clang-repl> int x = 42; clang-repl> auto capture = [&]() { return x * 2; }; In file included from <<< inputs >>>:1: input_line_4:1:17: error: non-local lambda expression cannot have a capture-default 1 | auto capture = [&]() { return x * 2; }; | ^ zsh: segmentation fault clang-repl --Xcc="-v" (lldb) bt * thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x8) * frame #0: 0x0000000107b4f8b8 libclang-cpp.19.1.dylib`clang::IncrementalParser::CleanUpPTU(clang::PartialTranslationUnit&) + 988 frame #1: 0x0000000107b4f1b4 libclang-cpp.19.1.dylib`clang::IncrementalParser::ParseOrWrapTopLevelDecl() + 416 frame #2: 0x0000000107b4fb94 libclang-cpp.19.1.dylib`clang::IncrementalParser::Parse(llvm::StringRef) + 612 frame #3: 0x0000000107b52fec libclang-cpp.19.1.dylib`clang::Interpreter::ParseAndExecute(llvm::StringRef, clang::Value*) + 180 frame #4: 0x0000000100003498 clang-repl`main + 3560 frame #5: 0x000000018d39a0e0 dyld`start + 2360 ``` Though the error is justified, we shouldn't be interested in exiting through a segfault in such cases. The issue is that empty named decls weren't being taken care of resulting into this assert https://github.com/llvm/llvm-project/blob/c1a229252617ed58f943bf3f4698bd8204ee0f04/clang/include/clang/AST/DeclarationName.h#L503 Can also be seen when the example is attempted through xeus-cpp-lite. 
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Jun 3, 2025
# Symptom We have seen SIGSEGV like this: ``` * thread #1, name = 'lldb-server', stop reason = SIGSEGV frame #0: 0x00007f39e529c993 libc.so.6`__pthread_kill_internal(signo=11, threadid=<unavailable>) at pthread_kill.c:46:37 ... * frame #5: 0x000056027c94fe48 lldb-server`lldb_private::process_linux::GetPtraceScope() + 72 frame #6: 0x000056027c92f94f lldb-server`lldb_private::process_linux::NativeProcessLinux::Attach(int) + 1087 ... ``` See [full stack trace](https://pastebin.com/X0d6QhYj). This happens on Linux where LLDB doesn't have access to `/proc/sys/kernel/yama/ptrace_scope`. A similar error (an unchecked `Error`) can be reproduced by running the newly added unit test without the fix. See the "Test" section below. # Root cause `GetPtraceScope()` ([code](https://github.com/llvm/llvm-project/blob/328f40f408c218f25695ea42c844e43bef38660b/lldb/source/Plugins/Process/Linux/Procfs.cpp#L77)) has the following `if` statement: ``` llvm::Expected<int> lldb_private::process_linux::GetPtraceScope() { ErrorOr<std::unique_ptr<MemoryBuffer>> ptrace_scope_file = getProcFile("sys/kernel/yama/ptrace_scope"); if (!*ptrace_scope_file) return errorCodeToError(ptrace_scope_file.getError()); ... } ``` The intention of the `if` statement is to check whether the `ptrace_scope_file` is an `Error` or not, and return the error if it is. However, the `operator*` of `ErrorOr` returns the value that is stored (which is a `std::unique_ptr<MemoryBuffer>`), so what the `if` condition actually do is to check if the unique pointer is non-null. Note that the method `ErrorOr::getStorage()` ([called by](https://github.com/llvm/llvm-project/blob/328f40f408c218f25695ea42c844e43bef38660b/llvm/include/llvm/Support/ErrorOr.h#L162-L164) `ErrorOr::operator *`) **does** assert on whether or not `HasError` has been set (see [ErrorOr.h](https://github.com/llvm/llvm-project/blob/328f40f408c218f25695ea42c844e43bef38660b/llvm/include/llvm/Support/ErrorOr.h#L235-L243)). However, it seems this wasn't executed, probably because the LLDB was a release build. # Fix The fix is simply remove the `*` in the said `if` statement.
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Fixes handling of unrolling directive when
n
is 0 or 1, and update docs.llvm#123331