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[VPlan] Fold lhs | (headermask && rhs) -> vp.merge rhs, true, lhs, evl#12

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[VPlan] Fold lhs | (headermask && rhs) -> vp.merge rhs, true, lhs, evl#12
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test/loop-vectorize/optimizeMaskToEVL-logical-or

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@lukel97 lukel97 commented Apr 22, 2026

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This is a combine on mask vectors that can show up with EVL tail folding.

Split off from llvm#190196

This is a combine on mask vectors that can show up with EVL tail folding.

Split off from llvm#190196
@lukel97

lukel97 commented Apr 22, 2026

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/test-suite

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@lukel97 lukel97 closed this Apr 22, 2026
lukel97 pushed a commit that referenced this pull request May 11, 2026
…input" (llvm#195551)

Reverts llvm#190863 due to buildbot breakage e.g.,
https://lab.llvm.org/buildbot/#/builders/52/builds/16951

```
Failed Tests (1):
  LLVM :: tools/llvm-profgen/filter-build-id.test
```
```
==llvm-profgen==3809550==ERROR: AddressSanitizer: container-overflow on address 0x6e80441e1762 at pc 0x6216c3f2cdce bp 0x7fff3c3ddf60 sp 0x7fff3c3dd710
READ of size 8 at 0x6e80441e1762 thread T0
    #0 0x6216c3f2cdcd in MemcmpInterceptorCommon(void*, int (*)(void const*, void const*, unsigned long), void const*, void const*, unsigned long) /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/compiler-rt/lib/asan/../sanitizer_common/sanitizer_common_interceptors.inc:848:7
    #1 0x6216c3f2d25c in bcmp /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/compiler-rt/lib/asan/../sanitizer_common/sanitizer_common_interceptors.inc:894:10
    #2 0x6216c400b836 in operator== /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/llvm/include/llvm/ADT/StringRef.h:914:10
    #3 0x6216c400b836 in operator!= /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/llvm/include/llvm/ADT/StringRef.h:917:69
    #4 0x6216c400b836 in llvm::sampleprof::PerfScriptReader::extractCallstack(llvm::sampleprof::TraceStream&, llvm::SmallVectorImpl<unsigned long>&) /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/llvm/tools/llvm-profgen/PerfReader.cpp:801:36
    #5 0x6216c400d37a in llvm::sampleprof::HybridPerfReader::parseSample(llvm::sampleprof::TraceStream&, unsigned long) /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/llvm/tools/llvm-profgen/PerfReader.cpp:881:8
    #6 0x6216c40150d8 in parseSample /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/llvm/tools/llvm-profgen/PerfReader.cpp:1118:3
    #7 0x6216c40150d8 in llvm::sampleprof::PerfScriptReader::parseEventOrSample(llvm::sampleprof::TraceStream&) /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/llvm/tools/llvm-profgen/PerfReader.cpp:1201:5
    #8 0x6216c401539a in llvm::sampleprof::PerfScriptReader::parseAndAggregateTrace() /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/llvm/tools/llvm-profgen/PerfReader.cpp:1210:5
    #9 0x6216c4018c88 in llvm::sampleprof::PerfScriptReader::parsePerfTraces() /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/llvm/tools/llvm-profgen/PerfReader.cpp:1457:3
    #10 0x6216c3ff2c7a in main /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/llvm/tools/llvm-profgen/llvm-profgen.cpp:229:19
    #11 0x72404502a8c0  (/usr/lib/x86_64-linux-gnu/libc.so.6+0x2a8c0) (BuildId: ae327f26c123ea1374623c41e676a4bf00e5c1cb)
    #12 0x72404502a9d7 in __libc_start_main (/usr/lib/x86_64-linux-gnu/libc.so.6+0x2a9d7) (BuildId: ae327f26c123ea1374623c41e676a4bf00e5c1cb)
    #13 0x6216c3f0f3d4 in _start (/home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm_build_asan/bin/llvm-profgen+0x2f083d4)
0x6e80441e1762 is located 18 bytes inside of 48-byte region [0x6e80441e1750,0x6e80441e1780)
allocated by thread T0 here:
    #0 0x6216c3feab0d in operator new(unsigned long) /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/compiler-rt/lib/asan/asan_new_delete.cpp:109:35
    #1 0x724045511c07 in __libcpp_allocate<char> /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/libcxx/include/__new/allocate.h:42:28
    #2 0x724045511c07 in allocate /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/libcxx/include/__memory/allocator.h:92:14
    #3 0x724045511c07 in allocate_at_least /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/libcxx/include/__memory/allocator.h:99:13
    #4 0x724045511c07 in allocate_at_least<std::__1::allocator<char> > /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/libcxx/include/__memory/allocator_traits.h:340:22
    #5 0x724045511c07 in __allocate_at_least<std::__1::allocator<char> > /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/libcxx/include/__memory/allocate_at_least.h:36:16
    #6 0x724045511c07 in __allocate_long_buffer /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/libcxx/include/string:2259:21
    #7 0x724045511c07 in std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>::__grow_by(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long) /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/libcxx/include/string:2769:25
    #8 0x6216c401d90a in __grow_by_without_replace /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/libcxx_install_asan/include/c++/v1/string:2795:3
    #9 0x6216c401d90a in std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>& std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>::append[abi:sqn230000]<char const*, 0>(char const*, char const*) /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/libcxx_install_asan/include/c++/v1/string:1431:9
    #10 0x6216c401d1a6 in std::__1::basic_istream<char, std::__1::char_traits<char>>& std::__1::getline[abi:sqn230000]<char, std::__1::char_traits<char>, std::__1::allocator<char>>(std::__1::basic_istream<char, std::__1::char_traits<char>>&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>&, char) /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/libcxx_install_asan/include/c++/v1/istream:1309:15
    #11 0x6216c4014a76 in getline<char, std::__1::char_traits<char>, std::__1::allocator<char> > /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/libcxx_install_asan/include/c++/v1/istream:1343:10
    #12 0x6216c4014a76 in advance /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/llvm/tools/llvm-profgen/PerfReader.h:52:10
    #13 0x6216c4014a76 in llvm::sampleprof::PerfScriptReader::parseAggregatedCount(llvm::sampleprof::TraceStream&) /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/llvm/tools/llvm-profgen/PerfReader.cpp:1110:13
    #14 0x6216c4015095 in parseSample /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/llvm/tools/llvm-profgen/PerfReader.cpp:1116:20
    #15 0x6216c4015095 in llvm::sampleprof::PerfScriptReader::parseEventOrSample(llvm::sampleprof::TraceStream&) /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/llvm/tools/llvm-profgen/PerfReader.cpp:1201:5
    #16 0x6216c401539a in llvm::sampleprof::PerfScriptReader::parseAndAggregateTrace() /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/llvm/tools/llvm-profgen/PerfReader.cpp:1210:5
    llvm#17 0x6216c4018c88 in llvm::sampleprof::PerfScriptReader::parsePerfTraces() /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/llvm/tools/llvm-profgen/PerfReader.cpp:1457:3
    llvm#18 0x6216c3ff2c7a in main /home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm-project/llvm/tools/llvm-profgen/llvm-profgen.cpp:229:19
    llvm#19 0x72404502a8c0  (/usr/lib/x86_64-linux-gnu/libc.so.6+0x2a8c0) (BuildId: ae327f26c123ea1374623c41e676a4bf00e5c1cb)
    llvm#20 0x72404502a9d7 in __libc_start_main (/usr/lib/x86_64-linux-gnu/libc.so.6+0x2a9d7) (BuildId: ae327f26c123ea1374623c41e676a4bf00e5c1cb)
    llvm#21 0x6216c3f0f3d4 in _start (/home/b/sanitizer-x86_64-linux-bootstrap-asan/build/llvm_build_asan/bin/llvm-profgen+0x2f083d4)
```
lukel97 pushed a commit that referenced this pull request May 11, 2026
… new constant interpreter (llvm#194851)

**Problem:**

A crash is triggered by clangd's hover feature when using C++23 and the
new bytecode interpreter, which calls `Expr::EvaluateAsRValue()` to
attempt constant folding on an expression under the cursor, even when it
is not a valid constant expression.

Tested versions: 22.1.3, Trunk (x86_64-pc-linux-gnu)

**How to reproduce:**
```cpp
struct S { void f(); };
void g() { S s; s.f(); }
```
Running `clangd --check=repro.cpp` 
(with `compile_flags.txt` containing `-std=c++23
-fexperimental-new-constant-interpreter`)
will crash. 

`Assertion ItemTypes.back() == toPrimType<T>() failed.`

You can observe the same crash by hovering over STL iterators like
`vec.begin()`.

**Relevant Stack Trace:**
```text
#8  clang::interp::InterpStack::pop<MemberPointer>()
#9  clang::interp::EvalEmitter::emitRet(PrimType, SourceInfo)
#10 clang::interp::Compiler<EvalEmitter>::visitExpr(Expr const*, bool)
#11 clang::interp::EvalEmitter::interpretExpr(Expr const*, bool, bool)
#12 clang::interp::Context::evaluateAsRValue(State&, Expr const*, APValue&)
#13 EvaluateAsRValue(EvalInfo&, Expr const*, APValue&)
#14 clang::Expr::EvaluateAsRValue(EvalResult&, ASTContext const&, bool) const
#15 clangd::(anon)::printExprValue(Expr const*, ASTContext const&)
#16 clangd::(anon)::printExprValue(SelectionTree::Node const*, ASTContext const&)
llvm#17 clangd::getHover(...)
```
*Basically: `textDocument/hover` → `getHover` → `EvaluateAsRValue` → new
constant interpreter → `MemberPointer` type mismatch on stack pop.*

When `Compiler<Emitter>::VisitMemberExpr()` encounters a non-static
`CXXMethodDecl` member (a bound member function expression such as `s.f`
in `s.f()`), it falls through to `visitDeclRef()`. This pushes a `FnPtr`
onto the interpreter stack. However, the caller expects a
`MemberPointer`, causing an assertion failure in `InterpStack::pop()`:

**Fix:**

* In `VisitMemberExpr()`, bail out early (`return false`) when the
member is a non-static `CXXMethodDecl`, before reaching
`visitDeclRef()`. This causes `EvaluateAsRValue()` to report failure
gracefully rather than crashing. Bound member function expressions
(`s.f`) are not valid constant expressions, so returning `false` should
be semantically correct.

**Testing:**
* Added AST unit test
(`EvaluateAsRValue.FailsGracefullyOnBoundMemberExpr`) that directly
isolates a bound `MemberExpr` and passes it to `EvaluateAsRValue()`,
asserting it returns `false` without crashing.

* Added clangd hover test
(Hover.NoCrashOnBoundMemberFunctionWithNewInterpreter)
  that reproduces the original crash scenario.

* *Note:* I could not add a Lit test because I believe this is
unreachable via normal `clang` invocations. `Sema` strictly catches
isolated bound member functions before constant evaluation. `clangd` has
a unique path to triggering this.

**Root cause:**

This is exposed by C++23 specifically due to (I think P2280R4 /
P2448R2):

- Relaxing the rules around "unknown" objects in constant evaluation,
allowing `s` in `s.f()` to proceed past the base object check even
though `s` is not constexpr and deferring failures to bytecode execution
rather than rejecting them structurally.

Assisted-by: gemini-cli

@tbaederr

---------

Co-authored-by: Timm Baeder <tbaeder@redhat.com>
lukel97 pushed a commit that referenced this pull request Jun 9, 2026
I recently noticed LLDB crash during execution of `script
print(lldb.SBDebugger().GetBroadcaster().GetName())` command:
```
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.	Program arguments: /home/sergei/llvm-project/build/bin/lldb-dap
 #0 0x000062735c3403d2 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/home/sergei/llvm-project/build/bin/lldb-dap+0x7c3d2)
 #1 0x000062735c33d7ec llvm::sys::RunSignalHandlers() (/home/sergei/llvm-project/build/bin/lldb-dap+0x797ec)
 #2 0x000062735c33d94c SignalHandler(int, siginfo_t*, void*) Signals.cpp:0:0
 #3 0x00007eaa6aa45330 (/lib/x86_64-linux-gnu/libc.so.6+0x45330)
 #4 0x00007eaa6bb0c092 lldb::SBBroadcaster::GetName() const (/home/sergei/llvm-project/build/bin/../lib/liblldb.so.23.0git+0x90c092)
 #5 0x00007eaa6bcb9a5d _wrap_SBBroadcaster_GetName LLDBWrapPython.cpp:0:0
 #6 0x00007eaa6a1df5f5 (/lib/x86_64-linux-gnu/libpython3.12.so.1.0+0x1df5f5)
 #7 0x00007eaa6a182b2c PyObject_Vectorcall (/lib/x86_64-linux-gnu/libpython3.12.so.1.0+0x182b2c)
 #8 0x00007eaa6a11d5ee _PyEval_EvalFrameDefault (/lib/x86_64-linux-gnu/libpython3.12.so.1.0+0x11d5ee)
 #9 0x00007eaa6a2a091f PyEval_EvalCode (/lib/x86_64-linux-gnu/libpython3.12.so.1.0+0x2a091f)
#10 0x00007eaa6a29c8b0 (/lib/x86_64-linux-gnu/libpython3.12.so.1.0+0x29c8b0)
#11 0x00007eaa6a11fbd3 _PyEval_EvalFrameDefault (/lib/x86_64-linux-gnu/libpython3.12.so.1.0+0x11fbd3)
#12 0x00007eaa6c4891b7 lldb_private::ScriptInterpreterPythonImpl::ExecuteOneLine(llvm::StringRef, lldb_private::CommandReturnObject*, lldb_private::ExecuteScriptOptions const&) (/home/sergei/llvm-project/build/bin/../lib/liblldb.so.23.0git+0x12891b7)
#13 0x00007eaa70326ff5 CommandObjectScriptingRun::DoExecute(llvm::StringRef, lldb_private::CommandReturnObject&) (/home/sergei/llvm-project/build/bin/../lib/liblldb.so.23.0git+0x5126ff5)
#14 0x00007eaa6bee3739 lldb_private::CommandObjectRaw::Execute(char const*, lldb_private::CommandReturnObject&) (/home/sergei/llvm-project/build/bin/../lib/liblldb.so.23.0git+0xce3739)
#15 0x00007eaa6bede09a lldb_private::CommandInterpreter::HandleCommand(char const*, lldb_private::LazyBool, lldb_private::CommandReturnObject&, bool) (/home/sergei/llvm-project/build/bin/../lib/liblldb.so.23.0git+0xcde09a)
#16 0x00007eaa6bb0f0f8 lldb::SBCommandInterpreter::HandleCommand(char const*, lldb::SBExecutionContext&, lldb::SBCommandReturnObject&, bool) (/home/sergei/llvm-project/build/bin/../lib/liblldb.so.23.0git+0x90f0f8)
llvm#17 0x00007eaa6bb0f265 lldb::SBCommandInterpreter::HandleCommand(char const*, lldb::SBCommandReturnObject&, bool) (/home/sergei/llvm-project/build/bin/../lib/liblldb.so.23.0git+0x90f265)
llvm#18 0x000062735c3707f3 lldb_dap::RunLLDBCommands[abi:cxx11](lldb::SBDebugger&, lldb::SBMutex, llvm::StringRef, llvm::ArrayRef<lldb_dap::protocol::String> const&, bool&, bool, bool) (/home/sergei/llvm-project/build/bin/lldb-dap+0xac7f3)
llvm#19 0x000062735c3a8019 lldb_dap::EvaluateRequestHandler::Run(lldb_dap::protocol::EvaluateArguments const&) const (/home/sergei/llvm-project/build/bin/lldb-dap+0xe4019)
llvm#20 0x000062735c3aba78 lldb_dap::RequestHandler<lldb_dap::protocol::EvaluateArguments, llvm::Expected<lldb_dap::protocol::EvaluateResponseBody>>::operator()(lldb_dap::protocol::Request const&) const (/home/sergei/llvm-project/build/bin/lldb-dap+0xe7a78)
llvm#21 0x000062735c3ce1bf lldb_dap::BaseRequestHandler::Run(lldb_dap::protocol::Request const&) (/home/sergei/llvm-project/build/bin/lldb-dap+0x10a1bf)
llvm#22 0x000062735c3577e7 lldb_dap::DAP::HandleObject(std::variant<lldb_dap::protocol::Request, lldb_dap::protocol::Response, lldb_dap::protocol::Event> const&) (/home/sergei/llvm-project/build/bin/lldb-dap+0x937e7)
llvm#23 0x000062735c358705 lldb_dap::DAP::Loop() (/home/sergei/llvm-project/build/bin/lldb-dap+0x94705)
llvm#24 0x000062735c2ed0c7 main (/home/sergei/llvm-project/build/bin/lldb-dap+0x290c7)
llvm#25 0x00007eaa6aa2a1ca __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:74:3
```
As far as I understand default constuctors should be covered by fuzzing
tests, so I don't know how to write test for that patch.
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