[AArch64] Neoverse V1 scheduling model #1

jvillette38 · 2025-02-11T09:57:32Z

This PR fixes scheduling model for the Neoverse V1. All information is taken from the Neoverse V1 Software Optimisation Guide:

https://developer.arm.com/documentation/pjdoc466751330-9685/6-0

Changes:

micro operations are reduced to maximum 3 and respect the number of max issues.
use ReleaseAtCycles to specify throughput
fix bypass latencies
fix some latencies/throughput

This merge request depends on llvm#126703 due to new test: llvm/test/tools/llvm-mca/AArch64/Neoverse/V1-scheduling-info.s.
This test reports all scheduling information changes from this patch.

@Rin18 may be interested.

This fix scheduling model for the Neoverse V1. All information is taken from the Neoverse V1 Software Optimisation Guide: https://developer.arm.com/documentation/pjdoc466751330-9685/6-0 Changes: - micro operations are reduced to maximum 3 - use ReleaseAtCycles to specify throughput - fix bypass latencies - fix some latencies/throughput

We can't guaranty that underlying string is 0-terminated and [String.size()] is even in the same allocation. https://lab.llvm.org/buildbot/#/builders/94/builds/4152/steps/17/logs/stdio ``` ==c-index-test==1846256==WARNING: MemorySanitizer: use-of-uninitialized-value #0 in clang::cxstring::createRef(llvm::StringRef) llvm-project/clang/tools/libclang/CXString.cpp:96:36 #1 in DumpCXCommentInternal llvm-project/clang/tools/c-index-test/c-index-test.c:521:39 #2 in DumpCXCommentInternal llvm-project/clang/tools/c-index-test/c-index-test.c:674:7 #3 in DumpCXCommentInternal llvm-project/clang/tools/c-index-test/c-index-test.c:674:7 #4 in DumpCXComment llvm-project/clang/tools/c-index-test/c-index-test.c:685:3 llvm#5 in PrintCursorComments llvm-project/clang/tools/c-index-test/c-index-test.c:768:7 Memory was marked as uninitialized #0 in __msan_allocated_memory llvm-project/compiler-rt/lib/msan/msan_interceptors.cpp:1023:5 #1 in Allocate llvm-project/llvm/include/llvm/Support/Allocator.h:172:7 #2 in Allocate llvm-project/llvm/include/llvm/Support/Allocator.h:216:12 #3 in Allocate llvm-project/llvm/include/llvm/Support/AllocatorBase.h:53:43 #4 in Allocate<char> llvm-project/llvm/include/llvm/Support/AllocatorBase.h:76:29 llvm#5 in convertCodePointToUTF8 llvm-project/clang/lib/AST/CommentLexer.cpp:42:30 llvm#6 in clang::comments::Lexer::resolveHTMLDecimalCharacterReference(llvm::StringRef) const llvm-project/clang/lib/AST/CommentLexer.cpp:76:10 llvm#7 in clang::comments::Lexer::lexHTMLCharacterReference(clang::comments::Token&) llvm-project/clang/lib/AST/CommentLexer.cpp:615:16 llvm#8 in consumeToken llvm-project/clang/include/clang/AST/CommentParser.h:62:9 llvm#9 in clang::comments::Parser::parseParagraphOrBlockCommand() llvm-project/clang/lib/AST/CommentParser.cpp llvm#10 in clang::comments::Parser::parseFullComment() llvm-project/clang/lib/AST/CommentParser.cpp:925:22 llvm#11 in clang::RawComment::parse(clang::ASTContext const&, clang::Preprocessor const*, clang::Decl const*) const llvm-project/clang/lib/AST/RawCommentList.cpp:221:12 llvm#12 in clang::ASTContext::getCommentForDecl(clang::Decl const*, clang::Preprocessor const*) const llvm-project/clang/lib/AST/ASTContext.cpp:714:35 llvm#13 in clang_Cursor_getParsedComment llvm-project/clang/tools/libclang/CXComment.cpp:36:35 llvm#14 in PrintCursorComments llvm-project/clang/tools/c-index-test/c-index-test.c:756:25 ```

Reverts llvm#125020 https://lab.llvm.org/buildbot/#/builders/24/builds/5252/steps/12/logs/stdio ``` ==c-index-test==2512295==ERROR: AddressSanitizer: heap-use-after-free on address 0xe19338c27992 at pc 0xc66be4784830 bp 0xe0e33660df00 sp 0xe0e33660d6e8 READ of size 23 at 0xe19338c27992 thread T1 #0 0xc66be478482c in printf_common(void*, char const*, std::__va_list) /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/compiler-rt/lib/asan/../sanitizer_common/sanitizer_common_interceptors_format.inc:563:9 #1 0xc66be478643c in vprintf /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/compiler-rt/lib/asan/../sanitizer_common/sanitizer_common_interceptors.inc:1699:1 #2 0xc66be478643c in printf /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/compiler-rt/lib/asan/../sanitizer_common/sanitizer_common_interceptors.inc:1757:1 #3 0xc66be4839384 in FilteredPrintingVisitor /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/tools/c-index-test/c-index-test.c:1359:5 #4 0xe4e3454f12e8 in clang::cxcursor::CursorVisitor::Visit(CXCursor, bool) /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/tools/libclang/CIndex.cpp:227:11 llvm#5 0xe4e3454f48a8 in bool clang::cxcursor::CursorVisitor::visitPreprocessedEntities<clang::PreprocessingRecord::iterator>(clang::PreprocessingRecord::iterator, clang::PreprocessingRecord::iterator, clang::PreprocessingRecord&, clang::FileID) CIndex.cpp 0xe19338c27992 is located 82 bytes inside of 105-byte region [0xe19338c27940,0xe19338c279a9) freed by thread T1 here: #0 0xc66be480040c in free /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:51:3 #1 0xc66be4839728 in GetCursorSource c-index-test.c #2 0xc66be4839368 in FilteredPrintingVisitor /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/tools/c-index-test/c-index-test.c:1360:12 #3 0xe4e3454f12e8 in clang::cxcursor::CursorVisitor::Visit(CXCursor, bool) /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/tools/libclang/CIndex.cpp:227:11 #4 0xe4e3454f48a8 in bool clang::cxcursor::CursorVisitor::visitPreprocessedEntities<clang::PreprocessingRecord::iterator>(clang::PreprocessingRecord::iterator, clang::PreprocessingRecord::iterator, clang::PreprocessingRecord&, clang::FileID) CIndex.cpp previously allocated by thread T1 here: #0 0xc66be4800680 in malloc /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:67:3 #1 0xe4e3456379b0 in safe_malloc /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/llvm/include/llvm/Support/MemAlloc.h:26:18 #2 0xe4e3456379b0 in createDup /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/tools/libclang/CXString.cpp:95:40 #3 0xe4e3456379b0 in clang::cxstring::createRef(llvm::StringRef) /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/tools/libclang/CXString.cpp:90:10 ```

…127087) Fixes the following crash in clang-repl ```c++ clang-repl> try { throw 1; } catch { 0; } In file included from <<< inputs >>>:1: input_line_1:1:23: error: expected '(' 1 | try { throw 1; } catch { 0; } | ^ | ( clang-repl: /home/vipul-cariappa/Documents/Workspace/cpp-py/llvms/llvm-project-a/clang/lib/AST/DeclBase.cpp:1757: void clang::DeclContext::addHiddenDecl(clang::Decl*): Assertion `D->getLexicalDeclContext() == this && "Decl inserted into wrong lexical context"' failed. #0 0x000059b28459e6da llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) /home/vipul-cariappa/Documents/Workspace/cpp-py/llvms/llvm-project-a/llvm/lib/Support/Unix/Signals.inc:804:22 #1 0x000059b28459eaed PrintStackTraceSignalHandler(void*) /home/vipul-cariappa/Documents/Workspace/cpp-py/llvms/llvm-project-a/llvm/lib/Support/Unix/Signals.inc:880:1 #2 0x000059b28459bf7f llvm::sys::RunSignalHandlers() /home/vipul-cariappa/Documents/Workspace/cpp-py/llvms/llvm-project-a/llvm/lib/Support/Signals.cpp:105:20 #3 0x000059b28459df8e SignalHandler(int, siginfo_t*, void*) /home/vipul-cariappa/Documents/Workspace/cpp-py/llvms/llvm-project-a/llvm/lib/Support/Unix/Signals.inc:418:13 #4 0x000077cdf444ea50 (/usr/lib/libc.so.6+0x42a50) llvm#5 0x000077cdf44aee3b pthread_kill (/usr/lib/libc.so.6+0xa2e3b) llvm#6 0x000077cdf444e928 raise (/usr/lib/libc.so.6+0x42928) llvm#7 0x000077cdf443156c abort (/usr/lib/libc.so.6+0x2556c) llvm#8 0x000077cdf44314d2 __assert_perror_fail (/usr/lib/libc.so.6+0x254d2) llvm#9 0x000077cdf4444c56 (/usr/lib/libc.so.6+0x38c56) llvm#10 0x000059b28495bfc4 clang::DeclContext::addHiddenDecl(clang::Decl*) /home/vipul-cariappa/Documents/Workspace/cpp-py/llvms/llvm-project-a/clang/lib/AST/DeclBase.cpp:1759:3 llvm#11 0x000059b28495c0f5 clang::DeclContext::addDecl(clang::Decl*) /home/vipul-cariappa/Documents/Workspace/cpp-py/llvms/llvm-project-a/clang/lib/AST/DeclBase.cpp:1785:37 llvm#12 0x000059b28773cc2a clang::Sema::ActOnStartTopLevelStmtDecl(clang::Scope*) /home/vipul-cariappa/Documents/Workspace/cpp-py/llvms/llvm-project-a/clang/lib/Sema/SemaDecl.cpp:20302:18 llvm#13 0x000059b286f1efdf clang::Parser::ParseTopLevelStmtDecl() /home/vipul-cariappa/Documents/Workspace/cpp-py/llvms/llvm-project-a/clang/lib/Parse/ParseDecl.cpp:6024:62 llvm#14 0x000059b286ef18ee clang::Parser::ParseExternalDeclaration(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec*) /home/vipul-cariappa/Documents/Workspace/cpp-py/llvms/llvm-project-a/clang/lib/Parse/Parser.cpp:1065:35 llvm#15 0x000059b286ef0702 clang::Parser::ParseTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&, clang::Sema::ModuleImportState&) /home/vipul-cariappa/Documents/Workspace/cpp-py/llvms/llvm-project-a/clang/lib/Parse/Parser.cpp:758:36 llvm#16 0x000059b28562dff2 clang::IncrementalParser::ParseOrWrapTopLevelDecl() /home/vipul-cariappa/Documents/Workspace/cpp-py/llvms/llvm-project-a/clang/lib/Interpreter/IncrementalParser.cpp:66:36 llvm#17 0x000059b28562e5b7 clang::IncrementalParser::Parse(llvm::StringRef) /home/vipul-cariappa/Documents/Workspace/cpp-py/llvms/llvm-project-a/clang/lib/Interpreter/IncrementalParser.cpp:132:8 llvm#18 0x000059b28561832b clang::Interpreter::Parse(llvm::StringRef) /home/vipul-cariappa/Documents/Workspace/cpp-py/llvms/llvm-project-a/clang/lib/Interpreter/Interpreter.cpp:570:8 llvm#19 0x000059b285618cbd clang::Interpreter::ParseAndExecute(llvm::StringRef, clang::Value*) /home/vipul-cariappa/Documents/Workspace/cpp-py/llvms/llvm-project-a/clang/lib/Interpreter/Interpreter.cpp:649:8 llvm#20 0x000059b2836f9343 main /home/vipul-cariappa/Documents/Workspace/cpp-py/llvms/llvm-project-a/clang/tools/clang-repl/ClangRepl.cpp:255:59 llvm#21 0x000077cdf443388e (/usr/lib/libc.so.6+0x2788e) llvm#22 0x000077cdf443394a __libc_start_main (/usr/lib/libc.so.6+0x2794a) llvm#23 0x000059b2836f7965 _start (./bin/clang-repl+0x73b8965) fish: Job 1, './bin/clang-repl' terminated by signal SIGABRT (Abort) ``` With this change: ```c++ clang-repl> try { throw 1; } catch { 0; } In file included from <<< inputs >>>:1: input_line_1:1:23: error: expected '(' 1 | try { throw 1; } catch { 0; } | ^ | ( error: Parsing failed. clang-repl> 1; clang-repl> %quit ```

For function declarations (i.e. func op has no entry block), the FunctionOpInterface method `insertArgument` and `eraseArgument` will cause segfault. This PR guards against manipulation of empty entry block by checking whether func op is external. An example can be seen in google/heir#1324 The segfault trace ``` #1 0x0000560f1289d9db PrintStackTraceSignalHandler(void*) /proc/self/cwd/external/llvm-project/llvm/lib/Support/Unix/Signals.inc:874:1 #2 0x0000560f1289b116 llvm::sys::RunSignalHandlers() /proc/self/cwd/external/llvm-project/llvm/lib/Support/Signals.cpp:105:5 #3 0x0000560f1289e145 SignalHandler(int) /proc/self/cwd/external/llvm-project/llvm/lib/Support/Unix/Signals.inc:415:1 #4 0x00007f829a3d9520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520) llvm#5 0x0000560f1257f8bc void __gnu_cxx::new_allocator<mlir::BlockArgument>::construct<mlir::BlockArgument, mlir::BlockArgument>(mlir::BlockArgument*, mlir::BlockArgument&&) /usr/lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/ext/new_allocator.h:162:23 llvm#6 0x0000560f1257f84d void std::allocator_traits<std::allocator<mlir::BlockArgument> >::construct<mlir::BlockArgument, mlir::BlockArgument>(std::allocator<mlir::BlockArgument>&, mlir::BlockArgument*, mlir::BlockArgument&&) /usr/lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/alloc_traits.h:520:2 llvm#7 0x0000560f12580498 void std::vector<mlir::BlockArgument, std::allocator<mlir::BlockArgument> >::_M_insert_aux<mlir::BlockArgument>(__gnu_cxx::__normal_iterator<mlir::BlockArgument*, std::vector<mlir::BlockArgument, std::allocator<mlir::BlockArgument> > >, mlir::BlockArgument&&) /usr/lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/vector.tcc:405:7 llvm#8 0x0000560f1257cf7e std::vector<mlir::BlockArgument, std::allocator<mlir::BlockArgument> >::insert(__gnu_cxx::__normal_iterator<mlir::BlockArgument const*, std::vector<mlir::BlockArgument, std::allocator<mlir::BlockArgument> > >, mlir::BlockArgument const&) /usr/lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/vector.tcc:154:6 llvm#9 0x0000560f1257b349 mlir::Block::insertArgument(unsigned int, mlir::Type, mlir::Location) /proc/self/cwd/external/llvm-project/mlir/lib/IR/Block.cpp:178:13 llvm#10 0x0000560f123d2a1c mlir::function_interface_impl::insertFunctionArguments(mlir::FunctionOpInterface, llvm::ArrayRef<unsigned int>, mlir::TypeRange, llvm::ArrayRef<mlir::DictionaryAttr>, llvm::ArrayRef<mlir::Location>, unsigned int, mlir::Type) /proc/self/cwd/external/llvm-project/mlir/lib/Interfaces/FunctionInterfaces.cpp:232:11 llvm#11 0x0000560f0be6b727 mlir::detail::FunctionOpInterfaceTrait<mlir::func::FuncOp>::insertArguments(llvm::ArrayRef<unsigned int>, mlir::TypeRange, llvm::ArrayRef<mlir::DictionaryAttr>, llvm::ArrayRef<mlir::Location>) /proc/self/cwd/bazel-out/k8-dbg/bin/external/llvm-project/mlir/include/mlir/Interfaces/FunctionInterfaces.h.inc:809:7 llvm#12 0x0000560f0be6b536 mlir::detail::FunctionOpInterfaceTrait<mlir::func::FuncOp>::insertArgument(unsigned int, mlir::Type, mlir::DictionaryAttr, mlir::Location) /proc/self/cwd/bazel-out/k8-dbg/bin/external/llvm-project/mlir/include/mlir/Interfaces/FunctionInterfaces.h.inc:796:7 ```

When compiling VLS SVE, the compiler often replaces VL-based offsets with immediate-based ones. This leads to a mismatch in the allowed addressing modes due to SVE loads/stores generally expecting immediate offsets relative to VL. For example, given: ```c svfloat64_t foo(const double *x) { svbool_t pg = svptrue_b64(); return svld1_f64(pg, x+svcntd()); } ``` When compiled with `-msve-vector-bits=128`, we currently generate: ```gas foo: ptrue p0.d mov x8, #2 ld1d { z0.d }, p0/z, [x0, x8, lsl #3] ret ``` Instead, we could be generating: ```gas foo: ldr z0, [x0, #1, mul vl] ret ``` Likewise for other types, stores, and other VLS lengths. This patch achieves the above by extending `SelectAddrModeIndexedSVE` to let constants through when `vscale` is known.

`TestReportData.py` is failing on the macOS CI with: ``` Traceback (most recent call last): File "/Users/ec2-user/jenkins/workspace/llvm.org/lldb-cmake/llvm-project/lldb/packages/Python/lldbsuite/test/lldbtest.py", line 1784, in test_method return attrvalue(self) File "/Users/ec2-user/jenkins/workspace/llvm.org/lldb-cmake/llvm-project/lldb/packages/Python/lldbsuite/test/decorators.py", line 148, in wrapper return func(*args, **kwargs) File "/Users/ec2-user/jenkins/workspace/llvm.org/lldb-cmake/llvm-project/lldb/test/API/functionalities/asan/TestReportData.py", line 28, in test_libsanitizers_asan self.asan_tests(libsanitizers=True) File "/Users/ec2-user/jenkins/workspace/llvm.org/lldb-cmake/llvm-project/lldb/test/API/functionalities/asan/TestReportData.py", line 60, in asan_tests self.expect( File "/Users/ec2-user/jenkins/workspace/llvm.org/lldb-cmake/llvm-project/lldb/packages/Python/lldbsuite/test/lldbtest.py", line 2490, in expect self.fail(log_msg) AssertionError: Ran command: "thread list" Got output: Process 3474 stopped * thread #1: tid = 0x38b5e9, 0x00007ff80f563b52 libsystem_kernel.dylib`__pthread_kill + 10, queue = 'com.apple.main-thread', stop reason = signal SIGABRT Expecting sub string: "stopped" (was found) Expecting sub string: "stop reason = Use of deallocated memory" (was not found) Process should be stopped due to ASan report ``` There isn't much to go off of in the log, so adding more to help us debug this.

These are macOS tests only and are currently failing on the x86_64 CI and on arm64 on recent versions of macOS/Xcode. The tests are failing because we're stopping in: ``` Process 17458 stopped * thread #1: tid = 0xbda69a, 0x00000002735bd000 libsystem_malloc.dylib`purgeable_print_self.cold.1, stop reason = EXC_BREAKPOINT (code=1, subcode=0x2735bd000) ``` instead of the libsanitizers library. This seems to be related to `-fsanitize-trivial-abi` support Skip these for now until we figure out the root cause.

… pointers (llvm#132261) Currently, the helpers to get fir::ExtendedValue out of hlfir::Entity use hlfir.declare second result (`#1`) in most cases. This is because this result is the same as the input and matches what FIR was getting before lowering to HLFIR. But this creates odd situations when both hlfir.declare are raw pointers and either result ends-up being used in the IR depending on whether the code was generated by a helper using fir::ExtendedValue, or via "pure HLFIR" helpers using the first result. This will typically prevent simple CSE and easy identification that two operation (e.g load/store) are touching the exact same memory location without using alias analysis or "manual detection" (looking for common hlfir.declare defining op). Hence, when hlfir.declare results are both raw pointers, use `#0` when producing `fir::ExtendedValue`. When `#0` is a fir.box, keep using `#1` because these are not the same. The only code change is in HLFIRTools.cpp and is pretty small, but there is a big test fallout of `#1` to `#0`.

…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 llvm#5 0x789f40ef in __asan::InitializePlatformInterceptors () at C:/llvm-mingw/llvm-mingw/llvm-project/compiler-rt/lib/asan/asan_win.cpp:190 llvm#6 0x789e0c3c in __asan::InitializeAsanInterceptors () at C:/llvm-mingw/llvm-mingw/llvm-project/compiler-rt/lib/asan/asan_interceptors.cpp:802 llvm#7 0x789ee6b5 in __asan::AsanInitInternal () at C:/llvm-mingw/llvm-mingw/llvm-project/compiler-rt/lib/asan/asan_rtl.cpp:442 llvm#8 0x789eefb0 in __asan::AsanInitFromRtl () at C:/llvm-mingw/llvm-mingw/llvm-project/compiler-rt/lib/asan/asan_rtl.cpp:522 llvm#9 __asan::AsanInitializer::AsanInitializer (this=<optimized out>) at C:/llvm-mingw/llvm-mingw/llvm-project/compiler-rt/lib/asan/asan_rtl.cpp:542 llvm#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 ... ```

…d A520 (llvm#132246) Inefficient SVE codegen occurs on at least two in-order cores, those being Cortex-A510 and Cortex-A520. For example a simple vector add ``` void foo(float a, float b, float dst, unsigned n) { for (unsigned i = 0; i < n; ++i) dst[i] = a[i] + b[i]; } ``` Vectorizes the inner loop into the following interleaved sequence of instructions. ``` add x12, x1, x10 ld1b { z0.b }, p0/z, [x1, x10] add x13, x2, x10 ld1b { z1.b }, p0/z, [x2, x10] ldr z2, [x12, #1, mul vl] ldr z3, [x13, #1, mul vl] dech x11 add x12, x0, x10 fadd z0.s, z1.s, z0.s fadd z1.s, z3.s, z2.s st1b { z0.b }, p0, [x0, x10] addvl x10, x10, #2 str z1, [x12, #1, mul vl] ``` By adjusting the target features to prefer fixed over scalable if the cost is equal we get the following vectorized loop. ``` ldp q0, q3, [x11, #-16] subs x13, x13, llvm#8 ldp q1, q2, [x10, #-16] add x10, x10, llvm#32 add x11, x11, llvm#32 fadd v0.4s, v1.4s, v0.4s fadd v1.4s, v2.4s, v3.4s stp q0, q1, [x12, #-16] add x12, x12, llvm#32 ``` Which is more efficient.

… A510/A520 (llvm#134606) Recommit. This work was done by llvm#132246 but failed buildbots due to the test introduced needing updates Inefficient SVE codegen occurs on at least two in-order cores, those being Cortex-A510 and Cortex-A520. For example a simple vector add ``` void foo(float a, float b, float dst, unsigned n) { for (unsigned i = 0; i < n; ++i) dst[i] = a[i] + b[i]; } ``` Vectorizes the inner loop into the following interleaved sequence of instructions. ``` add x12, x1, x10 ld1b { z0.b }, p0/z, [x1, x10] add x13, x2, x10 ld1b { z1.b }, p0/z, [x2, x10] ldr z2, [x12, #1, mul vl] ldr z3, [x13, #1, mul vl] dech x11 add x12, x0, x10 fadd z0.s, z1.s, z0.s fadd z1.s, z3.s, z2.s st1b { z0.b }, p0, [x0, x10] addvl x10, x10, #2 str z1, [x12, #1, mul vl] ``` By adjusting the target features to prefer fixed over scalable if the cost is equal we get the following vectorized loop. ``` ldp q0, q3, [x11, #-16] subs x13, x13, llvm#8 ldp q1, q2, [x10, #-16] add x10, x10, llvm#32 add x11, x11, llvm#32 fadd v0.4s, v1.4s, v0.4s fadd v1.4s, v2.4s, v3.4s stp q0, q1, [x12, #-16] add x12, x12, llvm#32 ``` Which is more efficient.

…s=128. (llvm#134068) When compiling with -msve-vector-bits=128 or vscale_range(1, 1) and when the offsets allow it, we can pair SVE LDR/STR instructions into Neon LDP/STP. For example, given: ```cpp #include <arm_sve.h> void foo(double const *ldp, double *stp) { svbool_t pg = svptrue_b64(); svfloat64_t ld1 = svld1_f64(pg, ldp); svfloat64_t ld2 = svld1_f64(pg, ldp+svcntd()); svst1_f64(pg, stp, ld1); svst1_f64(pg, stp+svcntd(), ld2); } ``` When compiled with `-msve-vector-bits=128`, we currently generate: ```gas foo: ldr z0, [x0] ldr z1, [x0, #1, mul vl] str z0, [x1] str z1, [x1, #1, mul vl] ret ``` With this patch, we instead generate: ```gas foo: ldp q0, q1, [x0] stp q0, q1, [x1] ret ``` This is an alternative, more targetted approach to llvm#127500.

…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 llvm#5 0x0000f16c1aa8a67c gsignal ./signal/../sysdeps/posix/raise.c:27:6 llvm#6 0x0000f16c1aa77130 abort ./stdlib/abort.c:81:7 llvm#7 0x0000b6eae9ad6628 (/home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/stage1.install/bin/clang+++0x8136628) llvm#8 0x0000b6eae72e95a8 (/home/tcwg-buildbot/worker/clang-aarch64-sve-vla-2stage/stage1.install/bin/clang+++0x59495a8) llvm#9 0x0000b6eae74ca9a8 (anonymous namespace)::AArch64LoadStoreOpt::findMatchingInsn(llvm::MachineInstrBundleIterator<llvm::MachineInstr, false>, (anonymous namespace)::LdStPairFlags&, unsigned int, bool) AArch64LoadStoreOptimizer.cpp:0:0 llvm#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 ```

…vailable (llvm#135343) When a frame is inlined, LLDB will display its name in backtraces as follows: ``` * thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.3 * frame #0: 0x0000000100000398 a.out`func() [inlined] baz(x=10) at inline.cpp:1:42 frame #1: 0x0000000100000398 a.out`func() [inlined] bar() at inline.cpp:2:37 frame #2: 0x0000000100000398 a.out`func() at inline.cpp:4:15 frame #3: 0x00000001000003c0 a.out`main at inline.cpp:7:5 frame #4: 0x000000026eb29ab8 dyld`start + 6812 ``` The longer the names get the more confusing this gets because the first function name that appears is the parent frame. My assumption (which may need some more surveying) is that for the majority of cases we only care about the actual frame name (not the parent). So this patch removes all the special logic that prints the parent frame. Another quirk of the current format is that the inlined frame name does not abide by the `${function.name-XXX}` format variables. We always just print the raw demangled name. With this patch, we would format the inlined frame name according to the `frame-format` setting (see the test-cases). If we really want to have the `parentFrame [inlined] inlinedFrame` format, we could expose it through a new `frame-format` variable (e..g., `${function.inlined-at-name}` and let the user decide where to place things.

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 llvm#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. ![image](https://github.com/user-attachments/assets/9b0e6ead-138e-4b06-9ad9-fcb9f8d5bf6e)

# 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 llvm#5: 0x000056027c94fe48 lldb-server`lldb_private::process_linux::GetPtraceScope() + 72 frame llvm#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.

…142952) This was removed in llvm#135343 in favour of making it a format variable, which we do here. This follows the precedent of the `[opt]` and `[artificial]` markers. Before: ``` thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.2 * frame #0: 0x000000010000037c a.out`inlined1() at inline.cpp:4:3 frame #1: 0x000000010000037c a.out`regular() at inline.cpp:6:17 frame #2: 0x00000001000003b8 a.out`inlined2() at inline.cpp:7:43 frame #3: 0x00000001000003b4 a.out`main at inline.cpp:10:3 frame #4: 0x0000000186345be4 dyld`start + 7040 ``` After (note the `[inlined]` markers): ``` thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.2 * frame #0: 0x000000010000037c a.out`inlined1() at inline.cpp:4:3 [inlined] frame #1: 0x000000010000037c a.out`regular() at inline.cpp:6:17 frame #2: 0x00000001000003b8 a.out`inlined2() at inline.cpp:7:43 [inlined] frame #3: 0x00000001000003b4 a.out`main at inline.cpp:10:3 frame #4: 0x0000000186345be4 dyld`start + 7040 ``` rdar://152642178

These were failing on our Windows on Arm bot, or more precisely, not even completing. This is because Microsoft's C runtime does extra parameter validation. So when we called _read with an invalid fd, it called an invalid parameter handler instead of returning an error. https://learn.microsoft.com/en-us/%20cpp/c-runtime-library/reference/read?view=msvc-170 https://learn.microsoft.com/en-us/%20cpp/c-runtime-library/parameter-validation?view=msvc-170 (lldb) run Process 8440 launched: 'C:\Users\tcwg\llvm-worker\lldb-aarch64-windows\build\tools\lldb\unittests\Host\HostTests.exe' (aarch64) Process 8440 stopped * thread #1, stop reason = Exception 0xc0000409 encountered at address 0x7ffb7453564c frame #0: 0x00007ffb7453564c ucrtbase.dll`_get_thread_local_invalid_parameter_handler + 652 ucrtbase.dll`_get_thread_local_invalid_parameter_handler: -> 0x7ffb7453564c <+652>: brk #0xf003 ucrtbase.dll`_invalid_parameter_noinfo: 0x7ffb74535650 <+0>: b 0x7ffb745354d8 ; _get_thread_local_invalid_parameter_handler + 280 0x7ffb74535654 <+4>: nop 0x7ffb74535658 <+8>: nop You can override this handler but I'm assuming that this reading after close isn't a crucial feature, so disabling the tests seems like the way to go. If it is crucial, we can check the fd before we use it. Tests added by llvm#143946.

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