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[flang] Implement C_F_STRPOINTER (Fortran 2023) - #1

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cenewcombe wants to merge 4 commits into
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feature/CPE-13669
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[flang] Implement C_F_STRPOINTER (Fortran 2023)#1
cenewcombe wants to merge 4 commits into
mainfrom
feature/CPE-13669

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@cenewcombe

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Implement C_F_STRPOINTER to associate a Fortran character pointer with a C string.

This intrinsic has two forms:

C_F_STRPOINTER(CSTRARRAY, FSTRPTR [,NCHARS]): Associates FSTRPTR with a C string array
C_F_STRPOINTER(CSTRPTR, FSTRPTR, NCHARS): Associates FSTRPTR with a C_PTR pointing to a character string
Implementation includes semantic validation, FIR lowering, and associated tests.

F2023 Standard: 18.2.3.5

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This file may not be consistent on this point, and not sure if reviewers will care, but in error messages like CSTRARRAY= argument to C_F_STRPOINTER() must be of kind ..., should there be single quotes around CSTRARRAY=? So it would be 'CSTRARRAY=' argument to C_F_STRPOINTER() must be of kind .... That seems to be the style most commonly used in the file.

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That's a good point. The file uses both, but I hadn't noticed. I most closely followed C_F_POINTER in implementing C_F_STRPOINTER, and I'm consistent with the formatting there. I'm comfortable leaving this as-is and if asked to change it, I will.

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The style guide (https://flang.llvm.org/docs/C%2B%2Bstyle.html#error-messages) does request single quotes for names from the program. I don't think that would apply to these dummy argument names from the specification, but I could be wrong.

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Looks good. I suggest declaring variables as const if they are single definition. Reviewers may care.

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Thanks. It's not consistent in this file, but I see that is straight from the style guide, will fix.

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Done ✔️

@Saldivarcher

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I don't see anything wrong with your PR 👍

@dreachem

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Did you want to make the change to use createArguments, as was requested in the other upstream PR?

@cenewcombe

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Did you want to make the change to use createArguments, as was requested in the other upstream PR?

@dreachem I looked at this earlier and I think C_F_STRPOINTER is okay in this regard. For F_C_STRING, we are generating a runtime call in flang/lib/Optimizer/Builder/Runtime/Character.cpp. For C_F_STRPOINTER it is all compile-time with inlined FIR operations i.e., fir::factory::associateMutableBox (from flang/lib/Optimizer/Builder/IntrinsicCall.cpp).

There is one runtime call to get the NCHARS argument if it is not provided using strlen, but it has a simple scalar signature and can be called directly without the helper.

This is all new to me though, so let me know if I've missed something.

@dreachem

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Did you want to make the change to use createArguments, as was requested in the other upstream PR?

@dreachem I looked at this earlier and I think C_F_STRPOINTER is okay in this regard. For F_C_STRING, we are generating a runtime call in flang/lib/Optimizer/Builder/Runtime/Character.cpp. For C_F_STRPOINTER it is all compile-time with inlined FIR operations i.e., fir::factory::associateMutableBox (from flang/lib/Optimizer/Builder/IntrinsicCall.cpp).

There is one runtime call to get the NCHARS argument if it is not provided using strlen, but it has a simple scalar signature and can be called directly without the helper.

This is all new to me though, so let me know if I've missed something.

OK. I think this is in good shape then. You can create the PR, and we'll learn more from the feedback you get.

@cenewcombe

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OK. I think this is in good shape then. You can create the PR, and we'll learn more from the feedback you get.

Thanks! I am going to let this one sit over the long weekend in case anything else comes in on the F_C_STRING PR. I'll go ahead and create the upstream PR on Tuesday if there's no new "lessons learned" from F_C_STRING.

cenewcombe pushed a commit that referenced this pull request Jan 22, 2026
**This patch adds a marker to make hidden frames more explicit.**

---

Hidden frames can be confusing for some users, who see that the indexes
of the frames in a backtrace are not contiguous. This patch aims to
lessen the confusion by adding a delimiter for the first and last non
hidden frame, i.e the boundaries.

IDE's like Xcode and VSCode represent those in the UI by having the
hidden frames either greyed out or collapsed.

It's not possible to do this in the CLI, therefore, this patch makes use
of 2 unicode characters to mark the beginning and end of the hidden
frames range.

This patch depends on:
- llvm#168603

# Examples

In the example below, frame `#2` to `llvm#7` are is hidden, and therefore,
frame `#1` is the first non hidden frame of the range while frame `llvm#8`
is the last non hidden frame:
<img width="488" height="112" alt="Screenshot 2025-11-18 at 18 41 11"
src="https://github.com/user-attachments/assets/a21431da-9729-4cf0-a6bc-024aa306fc45"
/>

If the selected frame is one of the 2 boundary frames, we replace the
delimiter character with the select character (`*`).

<img width="487" height="111" alt="Screenshot 2025-11-18 at 18 41 03"
src="https://github.com/user-attachments/assets/5616fa81-6db6-457d-9d1e-bbe46e710c26"
/>
<img width="488" height="111" alt="Screenshot 2025-11-18 at 18 40 55"
src="https://github.com/user-attachments/assets/93dfa6cf-0956-4718-b31c-f965ec72b56d"
/>
cenewcombe pushed a commit that referenced this pull request Jan 22, 2026
… all redeclarations (llvm#176188)

Fix handling of `lifetimebound` attributes on implicit `this` parameters across function redeclarations.

Previously, the lifetime analysis would miss `lifetimebound` attributes on implicit `this` parameters if they were only present on certain redeclarations of a method. This could lead to false negatives in the lifetime safety analysis. This change ensures that if any redeclaration of a method has the attribute, it will be properly detected and used in the analysis.

I can't seem to work around the crash in the earlier attempt llvm#172146.

Reproducer of the original crash:

```cpp
struct a {
  a &b() [[_Clang::__lifetimebound__]];
};
a &a::b() {}
```
This only crashes with `-target i686-w64-mingw32`. `bin/clang++ -c a.cpp` works fine.
Problematic merging logic:
```cpp
 // If Old has lifetimebound but New doesn't, add it to New.
  if (OldLBAttr && !NewLBAttr) {
    QualType NewMethodType = New->getType();
    QualType AttributedType =
        S.Context.getAttributedType(OldLBAttr, NewMethodType, NewMethodType);
    TypeLocBuilder TLB;
    TLB.pushFullCopy(NewTSI->getTypeLoc());
    AttributedTypeLoc TyLoc = TLB.push<AttributedTypeLoc>(AttributedType); // Crashes.
    TyLoc.setAttr(OldLBAttr);
    New->setType(AttributedType);
    New->setTypeSourceInfo(TLB.getTypeSourceInfo(S.Context, AttributedType));
  }
```

<details>
<summary>Crash</summary>

```
clang++: /REDACTED//llvm-project/clang/lib/Sema/TypeLocBuilder.cpp:89: TypeLoc clang::TypeLocBuilder::pushImpl(QualType, size_t, unsigned int): Assertion `TLast == LastTy && "mismatch between last type and new type's inner type"' failed.
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: bin/clang++ -target i686-w64-mingw32 -c /REDACTED//a.cpp
1.      /REDACTED//a.cpp:4:11: current parser token '{'
 #0 0x000055971cfcb838 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) /REDACTED//llvm-project/llvm/lib/Support/Unix/Signals.inc:842:13
 #1 0x000055971cfc9374 llvm::sys::RunSignalHandlers() /REDACTED//llvm-project/llvm/lib/Support/Signals.cpp:109:18
 #2 0x000055971cfcaf0c llvm::sys::CleanupOnSignal(unsigned long) /REDACTED//llvm-project/llvm/lib/Support/Unix/Signals.inc:0:3
 llvm#3 0x000055971cf38116 (anonymous namespace)::CrashRecoveryContextImpl::HandleCrash(int, unsigned long) /REDACTED//llvm-project/llvm/lib/Support/CrashRecoveryContext.cpp:73:5
 llvm#4 0x000055971cf38116 CrashRecoverySignalHandler(int) /REDACTED//llvm-project/llvm/lib/Support/CrashRecoveryContext.cpp:390:51
 llvm#5 0x00007fe9ebe49df0 (/lib/x86_64-linux-gnu/libc.so.6+0x3fdf0)
 llvm#6 0x00007fe9ebe9e95c __pthread_kill_implementation ./nptl/pthread_kill.c:44:76
 llvm#7 0x00007fe9ebe49cc2 raise ./signal/../sysdeps/posix/raise.c:27:6
 llvm#8 0x00007fe9ebe324ac abort ./stdlib/abort.c:81:3
 llvm#9 0x00007fe9ebe32420 __assert_perror_fail ./assert/assert-perr.c:31:1
llvm#10 0x000055971f969ade clang::TypeLocBuilder::pushImpl(clang::QualType, unsigned long, unsigned int) /REDACTED//llvm-project/clang/lib/Sema/TypeLocBuilder.cpp:93:3
llvm#11 0x000055971f237255 clang::QualType::hasLocalQualifiers() const /REDACTED//llvm-project/clang/include/clang/AST/TypeBase.h:1065:37
llvm#12 0x000055971f237255 clang::ConcreteTypeLoc<clang::UnqualTypeLoc, clang::AttributedTypeLoc, clang::AttributedType, clang::AttributedLocInfo>::isKind(clang::TypeLoc const&) /REDACTED//llvm-project/clang/include/clang/AST/TypeLoc.h:392:26
llvm#13 0x000055971f237255 clang::AttributedTypeLoc clang::TypeLoc::castAs<clang::AttributedTypeLoc>() const /REDACTED//llvm-project/clang/include/clang/AST/TypeLoc.h:79:5
llvm#14 0x000055971f237255 clang::AttributedTypeLoc clang::TypeLocBuilder::push<clang::AttributedTypeLoc>(clang::QualType) /REDACTED//llvm-project/clang/lib/Sema/TypeLocBuilder.h:106:47
llvm#15 0x000055971f280cc8 clang::AttributedTypeLoc::setAttr(clang::Attr const*) /REDACTED//llvm-project/clang/include/clang/AST/TypeLoc.h:1035:30
llvm#16 0x000055971f280cc8 mergeLifetimeBoundAttrOnMethod(clang::Sema&, clang::CXXMethodDecl*, clang::CXXMethodDecl const*) /REDACTED//llvm-project/clang/lib/Sema/SemaDecl.cpp:4497:11
llvm#17 0x000055971f280cc8 clang::Sema::MergeCompatibleFunctionDecls(clang::FunctionDecl*, clang::FunctionDecl*, clang::Scope*, bool) /REDACTED//llvm-project/clang/lib/Sema/SemaDecl.cpp:4528:5
llvm#18 0x000055971f27eb1f clang::Sema::MergeFunctionDecl(clang::FunctionDecl*, clang::NamedDecl*&, clang::Scope*, bool, bool) /REDACTED//llvm-project/clang/lib/Sema/SemaDecl.cpp:0:0
llvm#19 0x000055971f29c256 clang::Sema::CheckFunctionDeclaration(clang::Scope*, clang::FunctionDecl*, clang::LookupResult&, bool, bool) /REDACTED//llvm-project/clang/lib/Sema/SemaDecl.cpp:12371:9
llvm#20 0x000055971f28dab0 clang::Declarator::setRedeclaration(bool) /REDACTED//llvm-project/clang/include/clang/Sema/DeclSpec.h:2738:51
llvm#21 0x000055971f28dab0 clang::Sema::ActOnFunctionDeclarator(clang::Scope*, clang::Declarator&, clang::DeclContext*, clang::TypeSourceInfo*, clang::LookupResult&, llvm::MutableArrayRef<clang::TemplateParameterList*>, bool&) /REDACTED//llvm-project/clang/lib/Sema/SemaDecl.cpp:10877:9
llvm#22 0x000055971f2890fc clang::Sema::HandleDeclarator(clang::Scope*, clang::Declarator&, llvm::MutableArrayRef<clang::TemplateParameterList*>) /REDACTED//llvm-project/clang/lib/Sema/SemaDecl.cpp:0:11
llvm#23 0x000055971f2aab99 clang::Sema::ActOnStartOfFunctionDef(clang::Scope*, clang::Declarator&, llvm::MutableArrayRef<clang::TemplateParameterList*>, clang::SkipBodyInfo*, clang::Sema::FnBodyKind) /REDACTED//llvm-project/clang/lib/Sema/SemaDecl.cpp:15904:15
llvm#24 0x000055971efab286 clang::Parser::ParseFunctionDefinition(clang::ParsingDeclarator&, clang::Parser::ParsedTemplateInfo const&, clang::Parser::LateParsedAttrList*) /REDACTED//llvm-project/clang/lib/Parse/Parser.cpp:1364:23
llvm#25 0x000055971f013b40 clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&, clang::DeclaratorContext, clang::ParsedAttributes&, clang::Parser::ParsedTemplateInfo&, clang::SourceLocation*, clang::Parser::ForRangeInit*) /REDACTED//llvm-project/clang/lib/Parse/ParseDecl.cpp:2268:18
llvm#26 0x000055971efaa54f clang::Parser::ParseDeclOrFunctionDefInternal(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec&, clang::AccessSpecifier) /REDACTED//llvm-project/clang/lib/Parse/Parser.cpp:0:10
llvm#27 0x000055971efa9e36 clang::Parser::ParseDeclarationOrFunctionDefinition(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec*, clang::AccessSpecifier) /REDACTED//llvm-project/clang/lib/Parse/Parser.cpp:1202:12
llvm#28 0x000055971efa8df8 clang::Parser::ParseExternalDeclaration(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec*) /REDACTED//llvm-project/clang/lib/Parse/Parser.cpp:0:14
llvm#29 0x000055971efa7574 clang::Parser::ParseTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&, clang::Sema::ModuleImportState&) /REDACTED//llvm-project/clang/lib/Parse/Parser.cpp:743:10
llvm#30 0x000055971ef9c0ee clang::ParseAST(clang::Sema&, bool, bool) /REDACTED//llvm-project/clang/lib/Parse/ParseAST.cpp:169:5
llvm#31 0x000055971dbcdad6 clang::FrontendAction::Execute() /REDACTED//llvm-project/clang/lib/Frontend/FrontendAction.cpp:1317:10
llvm#32 0x000055971db3c5fd llvm::Error::getPtr() const /REDACTED//llvm-project/llvm/include/llvm/Support/Error.h:278:42
llvm#33 0x000055971db3c5fd llvm::Error::operator bool() /REDACTED//llvm-project/llvm/include/llvm/Support/Error.h:241:16
llvm#34 0x000055971db3c5fd clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) /REDACTED//llvm-project/clang/lib/Frontend/CompilerInstance.cpp:1006:23
llvm#35 0x000055971dcb4f9c clang::ExecuteCompilerInvocation(clang::CompilerInstance*) /REDACTED//llvm-project/clang/lib/FrontendTool/ExecuteCompilerInvocation.cpp:310:25
llvm#36 0x000055971a5e655e cc1_main(llvm::ArrayRef<char const*>, char const*, void*) /REDACTED//llvm-project/clang/tools/driver/cc1_main.cpp:304:15
llvm#37 0x000055971a5e29cb ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&, llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem>) /REDACTED//llvm-project/clang/tools/driver/driver.cpp:226:12
llvm#38 0x000055971a5e4c1d clang_main(int, char**, llvm::ToolContext const&)::$_0::operator()(llvm::SmallVectorImpl<char const*>&) const /REDACTED//llvm-project/clang/tools/driver/driver.cpp:0:12
llvm#39 0x000055971a5e4c1d int llvm::function_ref<int (llvm::SmallVectorImpl<char const*>&)>::callback_fn<clang_main(int, char**, llvm::ToolContext const&)::$_0>(long, llvm::SmallVectorImpl<char const*>&) /REDACTED//llvm-project/llvm/include/llvm/ADT/STLFunctionalExtras.h:46:12
llvm#40 0x000055971d9bfe79 clang::driver::CC1Command::Execute(llvm::ArrayRef<std::optional<llvm::StringRef>>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const::$_0::operator()() const /REDACTED//llvm-project/clang/lib/Driver/Job.cpp:442:30
llvm#41 0x000055971d9bfe79 void llvm::function_ref<void ()>::callback_fn<clang::driver::CC1Command::Execute(llvm::ArrayRef<std::optional<llvm::StringRef>>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const::$_0>(long) /REDACTED//llvm-project/llvm/include/llvm/ADT/STLFunctionalExtras.h:46:12
llvm#42 0x000055971cf37dbe llvm::function_ref<void ()>::operator()() const /REDACTED//llvm-project/llvm/include/llvm/ADT/STLFunctionalExtras.h:0:12
llvm#43 0x000055971cf37dbe llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) /REDACTED//llvm-project/llvm/lib/Support/CrashRecoveryContext.cpp:426:3
llvm#44 0x000055971d9bf5ac clang::driver::CC1Command::Execute(llvm::ArrayRef<std::optional<llvm::StringRef>>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const /REDACTED//llvm-project/clang/lib/Driver/Job.cpp:442:7
llvm#45 0x000055971d98422c clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const /REDACTED//llvm-project/clang/lib/Driver/Compilation.cpp:196:15
llvm#46 0x000055971d984447 clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&, bool) const /REDACTED//llvm-project/clang/lib/Driver/Compilation.cpp:246:13
llvm#47 0x000055971d99ee08 llvm::SmallVectorBase<unsigned int>::empty() const /REDACTED//llvm-project/llvm/include/llvm/ADT/SmallVector.h:83:46
llvm#48 0x000055971d99ee08 clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&) /REDACTED//llvm-project/clang/lib/Driver/Driver.cpp:2265:23
llvm#49 0x000055971a5e2303 clang_main(int, char**, llvm::ToolContext const&) /REDACTED//llvm-project/clang/tools/driver/driver.cpp:414:21
llvm#50 0x000055971a5f2527 main /usr/local/google/home/usx/build/tools/clang/tools/driver/clang-driver.cpp:17:10
llvm#51 0x00007fe9ebe33ca8 __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:74:3
llvm#52 0x00007fe9ebe33d65 call_init ./csu/../csu/libc-start.c:128:20
llvm#53 0x00007fe9ebe33d65 __libc_start_main ./csu/../csu/libc-start.c:347:5
llvm#54 0x000055971a5e0361 _start (bin/clang+++0x6636361)
clang++: error: clang frontend command failed with exit code 134 (use -v to see invocation)
clang version 23.0.0git (https://github.com/llvm/llvm-project.git 282a065)
Target: i686-w64-windows-gnu
Thread model: posix
InstalledDir: /usr/local/google/home/usx/build/bin
Build config: +assertions
clang++: note: diagnostic msg: 
********************
```

</details>
cenewcombe pushed a commit that referenced this pull request Jan 26, 2026
When a server is unable to allocate memory for the `_M` packet, it may
respond with an error code. In this case,
`GDBRemoteCommunicationClient::AllocateMemory()` sets
`m_supports_alloc_dealloc_memory` to `eLazyBoolYes`; `eLazyBoolNo` is
only used if the server cannot handle the packet at all. Before this
patch, `ProcessGDBRemote::DoAllocateMemory()` checked this flag and
returned `LLDB_INVALID_ADDRESS` without setting an error, which caused
`Process::CanJIT()` to set `m_can_jit = eCanJITYes`, resulting in
`IRMemoryMap::FindSpace()` attempting to allocate memory in the inferior
process and failing. With the patch,
`ProcessGDBRemote::DoAllocateMemory()` returns an error and `m_can_jit`
is set to `eCanJITNo`.

Example debug session:
```
(lldb) platform connect...
(lldb) file test
(lldb) br set...
(lldb) run
Process 100 launched:...
Process 100 stopped
* thread #1,...
(lldb) expr $x0
error: Couldn't allocate space for materialized struct: Couldn't malloc: address space is full
error: errored out in virtual lldb_private::LLVMUserExpression::DoExecute, couldn't PrepareToExecuteJITExpression
```
cenewcombe pushed a commit that referenced this pull request Jan 26, 2026
This reverts commit 99fab01.

llc was crashing in kernel-args.ll after this patch:
```
.---command stderr------------
| LLVM ERROR: Cannot select: t3: f32,ch = load<(non-temporal dereferenceable invariant load (s16), align 4, addrspace 7), sext from f16> t0, Constant:i32<36>, undef:i32
| In function: f16_arg
| PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace and instructions to reproduce the bug.
| Stack dump:
| 0.	Program arguments: /b/ml-opt-devrel-x86-64-b1/build/bin/llc -mtriple=r600 -mcpu=redwood
| 1.	Running pass 'Function Pass Manager' on module '<stdin>'.
| 2.	Running pass 'Unnamed pass: implement Pass::getPassName()' on function '@f16_arg'
|  #0 0x0000561402607438 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/b/ml-opt-devrel-x86-64-b1/build/bin/llc+0x81a7438)
|  #1 0x0000561402604b75 llvm::sys::RunSignalHandlers() (/b/ml-opt-devrel-x86-64-b1/build/bin/llc+0x81a4b75)
|  #2 0x00005614026081b1 SignalHandler(int, siginfo_t*, void*) Signals.cpp:0:0
|  llvm#3 0x00007f55eb45a050 (/lib/x86_64-linux-gnu/libc.so.6+0x3c050)
|  llvm#4 0x00007f55eb4a8eec (/lib/x86_64-linux-gnu/libc.so.6+0x8aeec)
|  llvm#5 0x00007f55eb459fb2 raise (/lib/x86_64-linux-gnu/libc.so.6+0x3bfb2)
|  llvm#6 0x00007f55eb444472 abort (/lib/x86_64-linux-gnu/libc.so.6+0x26472)
|  llvm#7 0x0000561402567005 llvm::report_fatal_error(llvm::Twine const&, bool) (/b/ml-opt-devrel-x86-64-b1/build/bin/llc+0x8107005)
|  llvm#8 0x00005614023e7ba7 llvm::SelectionDAGISel::CannotYetSelect(llvm::SDNode*) (/b/ml-opt-devrel-x86-64-b1/build/bin/llc+0x7f87ba7)
|  llvm#9 0x00005614023e6a7d llvm::SelectionDAGISel::SelectCodeCommon(llvm::SDNode*, unsigned char const*, unsigned int) (/b/ml-opt-devrel-x86-64-b1/build/bin/llc+0x7f86a7d)
| llvm#10 0x00005614023dae94 llvm::SelectionDAGISel::DoInstructionSelection() (/b/ml-opt-devrel-x86-64-b1/build/bin/llc+0x7f7ae94)
| llvm#11 0x00005614023d9e6a llvm::SelectionDAGISel::CodeGenAndEmitDAG() (/b/ml-opt-devrel-x86-64-b1/build/bin/llc+0x7f79e6a)
| llvm#12 0x00005614023d7b5e llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) (/b/ml-opt-devrel-x86-64-b1/build/bin/llc+0x7f77b5e)
| llvm#13 0x00005614023d4c30 llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) (/b/ml-opt-devrel-x86-64-b1/build/bin/llc+0x7f74c30)
| llvm#14 0x00005614023d22e0 llvm::SelectionDAGISelLegacy::runOnMachineFunction(llvm::MachineFunction&) (/b/ml-opt-devrel-x86-64-b1/build/bin/llc+0x7f722e0)
| llvm#15 0x0000561401611793 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (/b/ml-opt-devrel-x86-64-b1/build/bin/llc+0x71b1793)
| llvm#16 0x0000561401b790e5 llvm::FPPassManager::runOnFunction(llvm::Function&) (/b/ml-opt-devrel-x86-64-b1/build/bin/llc+0x77190e5)
| llvm#17 0x0000561401b80f72 llvm::FPPassManager::runOnModule(llvm::Module&) (/b/ml-opt-devrel-x86-64-b1/build/bin/llc+0x7720f72)
| llvm#18 0x0000561401b79b56 llvm::legacy::PassManagerImpl::run(llvm::Module&) (/b/ml-opt-devrel-x86-64-b1/build/bin/llc+0x7719b56)
| llvm#19 0x00005613ff4858f4 compileModule(char**, llvm::SmallVectorImpl<llvm::PassPlugin>&, llvm::LLVMContext&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>&) llc.cpp:0:0
| llvm#20 0x00005613ff482ed3 main (/b/ml-opt-devrel-x86-64-b1/build/bin/llc+0x5022ed3)
| llvm#21 0x00007f55eb44524a (/lib/x86_64-linux-gnu/libc.so.6+0x2724a)
| llvm#22 0x00007f55eb445305 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x27305)
| llvm#23 0x00005613ff47ea21 _start (/b/ml-opt-devrel-x86-64-b1/build/bin/llc+0x501ea21)
`-----------------------------
```
cenewcombe pushed a commit that referenced this pull request Feb 6, 2026
…lvm#178069)

Kernel panic is a special case, and there is no signal or exception for
that so we need to rely on special workaround called `dumptid`.
FreeBSDKernel plugin is supposed to find this thread and set it manually
through `SetStopInfo()` in `CalculateStopInfo()` like Mach core plugin
does.

Before (We had to find and select crashed thread list otherwise thread 1
was selected by default):
```
➜ sudo lldb /boot/panic/kernel -c /var/crash/vmcore.last
(lldb) target create "/boot/panic/kernel" --core "/var/crash/vmcore.last"
Core file '/var/crash/vmcore.last' (x86_64) was loaded.
(lldb) bt
* thread #1, name = '(pid 12991) dtrace'
  * frame #0: 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff8015882f780, flags=259) at sched_ule.c:2448:26
    frame #1: 0xffffffff80bd38d2 kernel`mi_switch(flags=259) at kern_synch.c:530:2
    frame #2: 0xffffffff80c29799 kernel`sleepq_switch(wchan=0xfffff8014edff300, pri=0) at subr_sleepqueue.c:608:2
    frame llvm#3: 0xffffffff80c29b76 kernel`sleepq_catch_signals(wchan=0xfffff8014edff300, pri=0) at subr_sleepqueue.c:523:3
    frame llvm#4: 0xffffffff80c29d32 kernel`sleepq_timedwait_sig(wchan=<unavailable>, pri=<unavailable>) at subr_sleepqueue.c:704:11
    frame llvm#5: 0xffffffff80bd2e2d kernel`_sleep(ident=0xfffff8014edff300, lock=0xffffffff81df2880, priority=768, wmesg="uwait", sbt=2573804118162, pr=0, flags=512) at kern_synch.c:215:10
    frame llvm#6: 0xffffffff80be8622 kernel`umtxq_sleep(uq=0xfffff8014edff300, wmesg="uwait", timo=0xfffffe0279cb3d20) at kern_umtx.c:843:11
    frame llvm#7: 0xffffffff80bef87a kernel`do_wait(td=0xfffff8015882f780, addr=<unavailable>, id=0, timeout=0xfffffe0279cb3d90, compat32=1, is_private=1) at kern_umtx.c:1316:12
    frame llvm#8: 0xffffffff80bed264 kernel`__umtx_op_wait_uint_private(td=0xfffff8015882f780, uap=0xfffffe0279cb3dd8, ops=<unavailable>) at kern_umtx.c:3990:10
    frame llvm#9: 0xffffffff80beaabe kernel`sys__umtx_op [inlined] kern__umtx_op(td=<unavailable>, obj=<unavailable>, op=<unavailable>, val=<unavailable>, uaddr1=<unavailable>, uaddr2=<unavailable>, ops=<unavailable>) at kern_umtx.c:4999:10
    frame llvm#10: 0xffffffff80beaa89 kernel`sys__umtx_op(td=<unavailable>, uap=<unavailable>) at kern_umtx.c:5024:10
    frame llvm#11: 0xffffffff81122cd1 kernel`amd64_syscall [inlined] syscallenter(td=0xfffff8015882f780) at subr_syscall.c:165:11
    frame llvm#12: 0xffffffff81122c19 kernel`amd64_syscall(td=0xfffff8015882f780, traced=0) at trap.c:1208:2
    frame llvm#13: 0xffffffff810f1dbb kernel`fast_syscall_common at exception.S:570
```

After:
```
➜ sudo ./build/bin/lldb /boot/panic/kernel -c /var/crash/vmcore.last
(lldb) target create "/boot/panic/kernel" --core "/var/crash/vmcore.last"
Core file '/var/crash/vmcore.last' (x86_64) was loaded.
(lldb) bt
* thread llvm#18, name = '(pid 5409) powerd (crashed)', stop reason = kernel panic
  * frame #0: 0xffffffff80bc6c91 kernel`__curthread at pcpu_aux.h:57:2 [inlined]
    frame #1: 0xffffffff80bc6c91 kernel`doadump(textdump=0) at kern_shutdown.c:399:2
    frame #2: 0xffffffff804b3b7a kernel`db_dump(dummy=<unavailable>, dummy2=<unavailable>, dummy3=<unavailable>, dummy4=<unavailable>) at db_command.c:596:10
    frame llvm#3: 0xffffffff804b396d kernel`db_command(last_cmdp=<unavailable>, cmd_table=<unavailable>, dopager=true) at db_command.c:508:3
    frame llvm#4: 0xffffffff804b362d kernel`db_command_loop at db_command.c:555:3
    frame llvm#5: 0xffffffff804b7026 kernel`db_trap(type=<unavailable>, code=<unavailable>) at db_main.c:267:3
    frame llvm#6: 0xffffffff80c16aaf kernel`kdb_trap(type=3, code=0, tf=0xfffffe01b605b930) at subr_kdb.c:790:13
    frame llvm#7: 0xffffffff8112154e kernel`trap(frame=<unavailable>) at trap.c:614:8
    frame llvm#8: 0xffffffff810f14c8 kernel`calltrap at exception.S:285
    frame llvm#9: 0xffffffff81da2290 kernel`cn_devtab + 64
    frame llvm#10: 0xfffffe01b605b8b0
    frame llvm#11: 0xffffffff84001c43 dtrace.ko`dtrace_panic(format=<unavailable>) at dtrace.c:652:2
    frame llvm#12: 0xffffffff84005524 dtrace.ko`dtrace_action_panic(ecb=0xfffff80539cad580) at dtrace.c:7022:2 [inlined]
    frame llvm#13: 0xffffffff840054de dtrace.ko`dtrace_probe(id=88998, arg0=14343377283488, arg1=<unavailable>, arg2=<unavailable>, arg3=<unavailable>, arg4=<unavailable>) at dtrace.c:7665:6
    frame llvm#14: 0xffffffff83e5213d systrace.ko`systrace_probe(sa=<unavailable>, type=<unavailable>, retval=<unavailable>) at systrace.c:226:2
    frame llvm#15: 0xffffffff8112318d kernel`syscallenter(td=0xfffff801318d5780) at subr_syscall.c:160:4 [inlined]
    frame llvm#16: 0xffffffff81123112 kernel`amd64_syscall(td=0xfffff801318d5780, traced=0) at trap.c:1208:2
    frame llvm#17: 0xffffffff810f1dbb kernel`fast_syscall_common at exception.S:570
```
cenewcombe pushed a commit that referenced this pull request Feb 6, 2026
In this PR i move the insertion point in the
`yieldReplacementForFusedProducer` because i ran into some issue where a
`tensor.extract_slices` tried to use a result of `affine.apply` that was
inserted at the end of the block instead of the start of it.

This is the full error of the test i added before this change:

```mlir
third-party/llvm-project/mlir/test/Interfaces/TilingInterface/tile-fuse-and-yield-using-scfforall.mlir:83:11: error: operand #1 does not dominate this use
  %pack = linalg.pack %gen#1
          ^
third-party/llvm-project/mlir/test/Interfaces/TilingInterface/tile-fuse-and-yield-using-scfforall.mlir:83:11: note: see current operation: %24 = "tensor.extract_slice"(%23, %36, %8) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xf32>, index, index) -> tensor<?x1024xf32>
third-party/llvm-project/mlir/test/Interfaces/TilingInterface/tile-fuse-and-yield-using-scfforall.mlir:71:12: note: operand defined here (op in the same block)
  %gen:2 = linalg.generic {
           ^
// -----// IR Dump After InterpreterPass Failed (transform-interpreter) //----- //
#map = affine_map<(d0, d1) -> (d0, d1)>
#map1 = affine_map<(d0) -> (d0 * 16)>
#map2 = affine_map<(d0) -> (d0 * -16 + 32)>
#map3 = affine_map<(d0) -> (16, d0 * -16 + 32)>
#map4 = affine_map<(d0) -> (d0 - 1)>
"builtin.module"() ({
  "func.func"() <{function_type = (tensor<32x1024xf32>) -> (tensor<32x1024xf32>, tensor<2x512x16x2xi8>), sym_name = "fuse_pack_consumer_into_multi_output_generic"}> ({
  ^bb0(%arg1: tensor<32x1024xf32>):
    %2 = "arith.constant"() <{value = 0 : i8}> : () -> i8
    %3 = "tensor.empty"() : () -> tensor<32x1024xf32>
    %4 = "tensor.empty"() : () -> tensor<32x1024xi8>
    %5 = "tensor.empty"() : () -> tensor<2x512x16x2xi8>
    %6:2 = "linalg.generic"(%arg1, %3, %4) <{indexing_maps = [#map, #map, #map], iterator_types = [#linalg.iterator_type<parallel>, #linalg.iterator_type<parallel>], operandSegmentSizes = array<i32: 1, 2>}> ({
    ^bb0(%arg9: f32, %arg10: f32, %arg11: i8):
      %41 = "arith.fptoui"(%arg9) : (f32) -> i8
      "linalg.yield"(%arg9, %41) : (f32, i8) -> ()
    }) : (tensor<32x1024xf32>, tensor<32x1024xf32>, tensor<32x1024xi8>) -> (tensor<32x1024xf32>, tensor<32x1024xi8>)
    %7:3 = "scf.forall"(%5, %3, %4) <{operandSegmentSizes = array<i32: 0, 0, 0, 3>, staticLowerBound = array<i64: 0>, staticStep = array<i64: 1>, staticUpperBound = array<i64: 2>}> ({
    ^bb0(%arg2: index, %arg3: tensor<2x512x16x2xi8>, %arg4: tensor<32x1024xf32>, %arg5: tensor<32x1024xi8>):
      %8 = "affine.apply"(%arg2) <{map = #map1}> : (index) -> index
      %9 = "affine.apply"(%arg2) <{map = #map2}> : (index) -> index
      %10 = "affine.min"(%arg2) <{map = #map3}> : (index) -> index
      %11 = "affine.apply"(%10) <{map = #map4}> : (index) -> index
      %12 = "affine.apply"(%arg2) <{map = #map1}> : (index) -> index
      %13 = "affine.apply"(%10) <{map = #map4}> : (index) -> index
      %14 = "affine.apply"(%arg2) <{map = #map1}> : (index) -> index
      %15 = "affine.apply"(%10) <{map = #map4}> : (index) -> index
      %16 = "affine.apply"(%arg2) <{map = #map1}> : (index) -> index
      %17 = "affine.apply"(%10) <{map = #map4}> : (index) -> index
      %18 = "tensor.extract_slice"(%arg1, %12, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xf32>, index, index) -> tensor<?x1024xf32>
      %19 = "tensor.empty"() : () -> tensor<32x1024xf32>
      %20 = "tensor.extract_slice"(%19, %14, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xf32>, index, index) -> tensor<?x1024xf32>
      %21 = "tensor.extract_slice"(%3, %14, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xf32>, index, index) -> tensor<?x1024xf32>
      %22 = "tensor.empty"() : () -> tensor<32x1024xi8>
      %23 = "tensor.extract_slice"(%22, %16, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xi8>, index, index) -> tensor<?x1024xi8>
      %24 = "tensor.extract_slice"(%4, %16, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xi8>, index, index) -> tensor<?x1024xi8>
      %25 = "tensor.empty"() : () -> tensor<32x1024xf32>
      %26 = "tensor.extract_slice"(%25, %38, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xf32>, index, index) -> tensor<?x1024xf32>
      %27 = "tensor.extract_slice"(%arg4, %38, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xf32>, index, index) -> tensor<?x1024xf32>
      %28 = "tensor.empty"() : () -> tensor<32x1024xi8>
      %29 = "tensor.extract_slice"(%28, %8, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xi8>, index, index) -> tensor<?x1024xi8>
      %30 = "tensor.extract_slice"(%arg5, %8, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xi8>, index, index) -> tensor<?x1024xi8>
      %31:2 = "linalg.generic"(%18, %27, %30) <{indexing_maps = [#map, #map, #map], iterator_types = [#linalg.iterator_type<parallel>, #linalg.iterator_type<parallel>], operandSegmentSizes = array<i32: 1, 2>}> ({
      ^bb0(%arg6: f32, %arg7: f32, %arg8: i8):
        %40 = "arith.fptoui"(%arg6) : (f32) -> i8
        "linalg.yield"(%arg6, %40) : (f32, i8) -> ()
      }) : (tensor<?x1024xf32>, tensor<?x1024xf32>, tensor<?x1024xi8>) -> (tensor<?x1024xf32>, tensor<?x1024xi8>)
      %32 = "tensor.extract_slice"(%6#1, %8, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<32x1024xi8>, index, index) -> tensor<?x1024xi8>
      %33 = "tensor.empty"() : () -> tensor<2x512x16x2xi8>
      %34 = "tensor.extract_slice"(%33, %arg2) <{operandSegmentSizes = array<i32: 1, 1, 0, 0>, static_offsets = array<i64: -9223372036854775808, 0, 0, 0>, static_sizes = array<i64: 1, 512, 16, 2>, static_strides = array<i64: 1, 1, 1, 1>}> : (tensor<2x512x16x2xi8>, index) -> tensor<1x512x16x2xi8>
      %35 = "tensor.extract_slice"(%arg3, %arg2) <{operandSegmentSizes = array<i32: 1, 1, 0, 0>, static_offsets = array<i64: -9223372036854775808, 0, 0, 0>, static_sizes = array<i64: 1, 512, 16, 2>, static_strides = array<i64: 1, 1, 1, 1>}> : (tensor<2x512x16x2xi8>, index) -> tensor<1x512x16x2xi8>
      %36 = "linalg.pack"(%31#1, %35, %2) <{inner_dims_pos = array<i64: 0, 1>, operandSegmentSizes = array<i32: 1, 1, 1, 0>, static_inner_tiles = array<i64: 16, 2>}> : (tensor<?x1024xi8>, tensor<1x512x16x2xi8>, i8) -> tensor<1x512x16x2xi8>
      %37 = "affine.apply"(%10) <{map = #map4}> : (index) -> index
      %38 = "affine.apply"(%arg2) <{map = #map1}> : (index) -> index
      %39 = "affine.apply"(%10) <{map = #map4}> : (index) -> index
      "scf.forall.in_parallel"() ({
        "tensor.parallel_insert_slice"(%36, %arg3, %arg2) <{operandSegmentSizes = array<i32: 1, 1, 1, 0, 0>, static_offsets = array<i64: -9223372036854775808, 0, 0, 0>, static_sizes = array<i64: 1, 512, 16, 2>, static_strides = array<i64: 1, 1, 1, 1>}> : (tensor<1x512x16x2xi8>, tensor<2x512x16x2xi8>, index) -> ()
        "tensor.parallel_insert_slice"(%31#0, %arg4, %38, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<?x1024xf32>, tensor<32x1024xf32>, index, index) -> ()
        "tensor.parallel_insert_slice"(%31#1, %arg5, %8, %10) <{operandSegmentSizes = array<i32: 1, 1, 1, 1, 0>, static_offsets = array<i64: -9223372036854775808, 0>, static_sizes = array<i64: -9223372036854775808, 1024>, static_strides = array<i64: 1, 1>}> : (tensor<?x1024xi8>, tensor<32x1024xi8>, index, index) -> ()
      }) : () -> ()
    }) : (tensor<2x512x16x2xi8>, tensor<32x1024xf32>, tensor<32x1024xi8>) -> (tensor<2x512x16x2xi8>, tensor<32x1024xf32>, tensor<32x1024xi8>)
    "func.return"(%7#1, %7#0) : (tensor<32x1024xf32>, tensor<2x512x16x2xi8>) -> ()
  }) : () -> ()
  "builtin.module"() ({
    "transform.named_sequence"() <{arg_attrs = [{transform.readonly}], function_type = (!transform.any_op) -> (), sym_name = "__transform_main"}> ({
    ^bb0(%arg0: !transform.any_op):
      %0 = "transform.structured.match"(%arg0) <{ops = ["linalg.pack"]}> : (!transform.any_op) -> !transform.any_op
      %1:2 = "transform.test.fuse_and_yield"(%0) <{tile_interchange = [], tile_sizes = [1], use_forall = true}> : (!transform.any_op) -> (!transform.any_op, !transform.any_op)
      "transform.yield"() : () -> ()
    }) : () -> ()
  }) {transform.with_named_sequence} : () -> ()
}) : () -> ()
``` 

I also noticed that Interface tests are missing from the bazel overlay
so i also added this.
cenewcombe pushed a commit that referenced this pull request Feb 6, 2026
…m#167446)

Add SVE optimization for AArch64 architectures. The idea is to use
predicate registers to avoid branching.
Microbench in repo shows considerable improvements on NV GB10 (locked on
largest X925):

```
======================================================================
BENCHMARK STATISTICS (time in nanoseconds)
======================================================================

memcpy_Google_A:
  Old - Mean: 3.1257 ns, Median: 3.1162 ns
  New - Mean: 2.8402 ns, Median: 2.8265 ns
  Improvement: +9.14% (mean), +9.30% (median)

memcpy_Google_B:
  Old - Mean: 2.3171 ns, Median: 2.3159 ns
  New - Mean: 1.6589 ns, Median: 1.6593 ns
  Improvement: +28.40% (mean), +28.35% (median)

memcpy_Google_D:
  Old - Mean: 8.7602 ns, Median: 8.7645 ns
  New - Mean: 8.4307 ns, Median: 8.4308 ns
  Improvement: +3.76% (mean), +3.81% (median)

memcpy_Google_L:
  Old - Mean: 1.7137 ns, Median: 1.7091 ns
  New - Mean: 1.4530 ns, Median: 1.4553 ns
  Improvement: +15.22% (mean), +14.85% (median)

memcpy_Google_M:
  Old - Mean: 1.9823 ns, Median: 1.9825 ns
  New - Mean: 1.4826 ns, Median: 1.4840 ns
  Improvement: +25.20% (mean), +25.15% (median)

memcpy_Google_Q:
  Old - Mean: 1.6812 ns, Median: 1.6784 ns
  New - Mean: 1.1538 ns, Median: 1.1517 ns
  Improvement: +31.37% (mean), +31.38% (median)

memcpy_Google_S:
  Old - Mean: 2.1816 ns, Median: 2.1786 ns
  New - Mean: 1.6297 ns, Median: 1.6287 ns
  Improvement: +25.29% (mean), +25.24% (median)

memcpy_Google_U:
  Old - Mean: 2.2851 ns, Median: 2.2825 ns
  New - Mean: 1.7219 ns, Median: 1.7187 ns
  Improvement: +24.65% (mean), +24.70% (median)

memcpy_Google_W:
  Old - Mean: 2.0408 ns, Median: 2.0361 ns
  New - Mean: 1.5260 ns, Median: 1.5252 ns
  Improvement: +25.23% (mean), +25.09% (median)

uniform_384_to_4096:
  Old - Mean: 26.9067 ns, Median: 26.8845 ns
  New - Mean: 26.8083 ns, Median: 26.8149 ns
  Improvement: +0.37% (mean), +0.26% (median)
```
The beginning of the memcpy function looks like the following:
```
Dump of assembler code for function _ZN22__llvm_libc_22_0_0_git6memcpyEPvPKvm:
   0x0000000000001340 <+0>:     cbz     x2, 0x143c <_ZN22__llvm_libc_22_0_0_git6memcpyEPvPKvm+252>
   0x0000000000001344 <+4>:     cbz     x0, 0x1440 <_ZN22__llvm_libc_22_0_0_git6memcpyEPvPKvm+256>
   0x0000000000001348 <+8>:     cbz     x1, 0x1444 <_ZN22__llvm_libc_22_0_0_git6memcpyEPvPKvm+260>
   0x000000000000134c <+12>:    subs    x8, x2, #0x20
   0x0000000000001350 <+16>:    b.hi    0x1374 <_ZN22__llvm_libc_22_0_0_git6memcpyEPvPKvm+52>  // b.pmore
   0x0000000000001354 <+20>:    rdvl    x8, #1
   0x0000000000001358 <+24>:    whilelo p0.b, xzr, x2
   0x000000000000135c <+28>:    ld1b    {z0.b}, p0/z, [x1]
   0x0000000000001360 <+32>:    whilelo p1.b, x8, x2
   0x0000000000001364 <+36>:    ld1b    {z1.b}, p1/z, [x1, #1, mul vl]
   0x0000000000001368 <+40>:    st1b    {z0.b}, p0, [x0]
   0x000000000000136c <+44>:    st1b    {z1.b}, p1, [x0, #1, mul vl]
   0x0000000000001370 <+48>:    ret
```

---------

Co-authored-by: Guillaume Chatelet <chatelet.guillaume@gmail.com>
cenewcombe pushed a commit that referenced this pull request Feb 6, 2026
…8306)

In FreeBSD, allproc is a prepend list and new processes are appended at
head. This results in reverse pid order, so we first need to order pid
incrementally then print threads according to the correct order.

Before:
```
Process 0 stopped
* thread #1: tid = 101866, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff8015882f780, flags=259) at sched_ule.c:2448:26, name = '(pid 12991) dtrace'
  thread #2: tid = 101915, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff80158825780, flags=259) at sched_ule.c:2448:26, name = '(pid 11509) zsh'
  thread llvm#3: tid = 101942, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff80142599000, flags=259) at sched_ule.c:2448:26, name = '(pid 11504) ftcleanup'
  thread llvm#4: tid = 101545, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff80131898000, flags=259) at sched_ule.c:2448:26, name = '(pid 5599) zsh'
  thread llvm#5: tid = 100905, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff80131899000, flags=259) at sched_ule.c:2448:26, name = '(pid 5598) sshd-session'
  thread llvm#6: tid = 101693, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff8015886e780, flags=259) at sched_ule.c:2448:26, name = '(pid 5595) sshd-session'
  thread llvm#7: tid = 101626, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff801588be000, flags=259) at sched_ule.c:2448:26, name = '(pid 5592) sh'
...
```

After:
```
(lldb) thread list
Process 0 stopped
* thread #1: tid = 100000, 0xffffffff80bf9322 kernel`sched_switch(td=0xffffffff81abe840, flags=259) at sched_ule.c:2448:26, name = '(pid 0) kernel'
  thread #2: tid = 100035, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff801052d9780, flags=259) at sched_ule.c:2448:26, name = '(pid 0) kernel/softirq_0'
  thread llvm#3: tid = 100036, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff801052d9000, flags=259) at sched_ule.c:2448:26, name = '(pid 0) kernel/softirq_1'
  thread llvm#4: tid = 100037, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff801052d8780, flags=259) at sched_ule.c:2448:26, name = '(pid 0) kernel/softirq_2'
  thread llvm#5: tid = 100038, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff801052d8000, flags=259) at sched_ule.c:2448:26, name = '(pid 0) kernel/softirq_3'
  thread llvm#6: tid = 100039, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff801052d7780, flags=259) at sched_ule.c:2448:26, name = '(pid 0) kernel/softirq_4'
  thread llvm#7: tid = 100040, 0xffffffff80bf9322 kernel`sched_switch(td=0xfffff801052d7000, flags=259) at sched_ule.c:2448:26, name = '(pid 0) kernel/softirq_5'
...
```

Signed-off-by: Minsoo Choo <minsoochoo0122@proton.me>
cenewcombe pushed a commit that referenced this pull request Feb 27, 2026
Using code/ideas from the x86 backend to optimize a select on a bitcast
integer. The previous aarch64 approach was to individually extract the
bits from the mask, which is kind of terrible.

https://rust.godbolt.org/z/576sndT66

```llvm
define void @if_then_else8(ptr %out, i8 %mask, ptr %if_true, ptr %if_false) {
start:
  %t = load <8 x i32>, ptr %if_true, align 4
  %f = load <8 x i32>, ptr %if_false, align 4
  %m = bitcast i8 %mask to <8 x i1>
  %s = select <8 x i1> %m, <8 x i32> %t, <8 x i32> %f
  store <8 x i32> %s, ptr %out, align 4
  ret void
}
```

turned into 

```asm
if_then_else8:                          // @if_then_else8
        sub     sp, sp, llvm#16
        ubfx    w8, w1, llvm#4, #1
        and     w11, w1, #0x1
        ubfx    w9, w1, llvm#5, #1
        fmov    s1, w11
        ubfx    w10, w1, #1, #1
        fmov    s0, w8
        ubfx    w8, w1, llvm#6, #1
        ldp     q5, q2, [x3]
        mov     v1.h[1], w10
        ldp     q4, q3, [x2]
        mov     v0.h[1], w9
        ubfx    w9, w1, #2, #1
        mov     v1.h[2], w9
        ubfx    w9, w1, llvm#3, #1
        mov     v0.h[2], w8
        ubfx    w8, w1, llvm#7, #1
        mov     v1.h[3], w9
        mov     v0.h[3], w8
        ushll   v1.4s, v1.4h, #0
        ushll   v0.4s, v0.4h, #0
        shl     v1.4s, v1.4s, llvm#31
        shl     v0.4s, v0.4s, llvm#31
        cmlt    v1.4s, v1.4s, #0
        cmlt    v0.4s, v0.4s, #0
        bsl     v1.16b, v4.16b, v5.16b
        bsl     v0.16b, v3.16b, v2.16b
        stp     q1, q0, [x0]
        add     sp, sp, llvm#16
        ret
```

With this PR that instead emits

```asm
if_then_else8:
   adrp x8, .LCPI0_1
   dup v0.4s, w1
   ldr q1, [x8, :lo12:.LCPI0_1]
   adrp x8, .LCPI0_0
   ldr q2, [x8, :lo12:.LCPI0_0]
   ldp q4, q3, [x2]
   and v1.16b, v0.16b, v1.16b
   and v0.16b, v0.16b, v2.16b
   ldp q5, q2, [x3]
   cmeq v1.4s, v1.4s, #0
   cmeq v0.4s, v0.4s, #0
   bsl v1.16b, v2.16b, v3.16b
   bsl v0.16b, v5.16b, v4.16b
   stp q0, q1, [x0]
   ret
```

So substantially shorter. Instead of building the mask
element-by-element, this approach (by virtue of not splitting) instead
splats the mask value into all vector lanes, performs a bitwise and with
powers of 2, and compares with zero to construct the mask vector.

cc rust-lang/rust#122376
cc llvm#175769
cenewcombe pushed a commit that referenced this pull request Mar 3, 2026
llvm#184186)

…83889)"

This reverts commit 2342db0.

Revert "[CMake] Propagate dependencies to OBJECT libraries in
`add_llvm_library` (llvm#183541)"

This reverts commit e3c0454.
cenewcombe pushed a commit that referenced this pull request Mar 12, 2026
`SE.getUMaxExpr` causes assertion failure due to type mismatch here:


https://github.com/llvm/llvm-project/blob/main/llvm/lib/Analysis/LoopAccessAnalysis.cpp#L253

Running `opt -S -p loop-vectorize -debug-only=loop-vectorize
llvm/test/Analysis/LoopAccessAnalysis/type-mismatch-in-scalar-evolution.ll
` without the changes made in LoopAccessAnalysis.cpp causes assertion
failure.
Attaching the stack dump for reference:
```
LV: Checking a loop in 'loop_contains_store_assumed_bounds' from input.ll
LV: Loop hints: force=? width=4 interleave=0
LV: Found a loop: for.body
LV: Found an induction variable.
opt: /home/kshitij/llvm-project/llvm/lib/Analysis/ScalarEvolution.cpp:3918: const llvm::SCEV* llvm::ScalarEvolution::getMinMaxExpr(llvm::SCEVTypes, llvm::SmallVectorImpl<const llvm::SCEV*>&): Assertion `getEffectiveSCEVType(Ops[i]->getType()) == ETy && "Operand types don't match!"' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace and instructions to reproduce the bug.
Stack dump:
0.	Program arguments: opt -S -passes=loop-vectorize -debug-only=loop-vectorize -force-vector-width=4 -disable-output input.ll
1.	Running pass "function(loop-vectorize<no-interleave-forced-only;no-vectorize-forced-only;>)" on module "input.ll"
2.	Running pass "loop-vectorize<no-interleave-forced-only;no-vectorize-forced-only;>" on function "loop_contains_store_assumed_bounds"
 #0 0x000058ee97c5e652 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/usr/local/bin/opt+0x4f44652)
 #1 0x000058ee97c5af0f llvm::sys::RunSignalHandlers() (/usr/local/bin/opt+0x4f40f0f)
 #2 0x000058ee97c5b05c SignalHandler(int, siginfo_t*, void*) Signals.cpp:0:0
 llvm#3 0x00007c49d4c45330 (/lib/x86_64-linux-gnu/libc.so.6+0x45330)
 llvm#4 0x00007c49d4c9eb2c __pthread_kill_implementation ./nptl/pthread_kill.c:44:76
 llvm#5 0x00007c49d4c9eb2c __pthread_kill_internal ./nptl/pthread_kill.c:78:10
 llvm#6 0x00007c49d4c9eb2c pthread_kill ./nptl/pthread_kill.c:89:10
 llvm#7 0x00007c49d4c4527e raise ./signal/../sysdeps/posix/raise.c:27:6
 llvm#8 0x00007c49d4c288ff abort ./stdlib/abort.c:81:7
 llvm#9 0x00007c49d4c2881b _nl_load_domain ./intl/loadmsgcat.c:1177:9
llvm#10 0x00007c49d4c3b517 (/lib/x86_64-linux-gnu/libc.so.6+0x3b517)
llvm#11 0x000058ee98003fdb llvm::ScalarEvolution::getMinMaxExpr(llvm::SCEVTypes, llvm::SmallVectorImpl<llvm::SCEV const*>&) (/usr/local/bin/opt+0x52e9fdb)
llvm#12 0x000058ee98004507 llvm::ScalarEvolution::getUMaxExpr(llvm::SCEV const*, llvm::SCEV const*) (/usr/local/bin/opt+0x52ea507)
llvm#13 0x000058ee980dc728 llvm::getStartAndEndForAccess(llvm::Loop const*, llvm::SCEV const*, llvm::Type*, llvm::SCEV const*, llvm::SCEV const*, llvm::ScalarEvolution*, llvm::DenseMap<std::pair<llvm::SCEV const*, llvm::Type*>, std::pair<llvm::SCEV const*, llvm::SCEV const*>, llvm::DenseMapInfo<std::pair<llvm::SCEV const*, llvm::Type*>, void>, llvm::detail::DenseMapPair<std::pair<llvm::SCEV const*, llvm::Type*>, std::pair<llvm::SCEV const*, llvm::SCEV const*>>>*, llvm::DominatorTree*, llvm::AssumptionCache*, std::optional<llvm::ScalarEvolution::LoopGuards>&) (/usr/local/bin/opt+0x53c2728)
llvm#14 0x000058ee9814008b llvm::isDereferenceableAndAlignedInLoop(llvm::LoadInst*, llvm::Loop*, llvm::ScalarEvolution&, llvm::DominatorTree&, llvm::AssumptionCache*, llvm::SmallVectorImpl<llvm::SCEVPredicate const*>*) (/usr/local/bin/opt+0x542608b)
llvm#15 0x000058ee9a0fa1ca llvm::LoopVectorizationLegality::canUncountableExitConditionLoadBeMoved(llvm::BasicBlock*) (/usr/local/bin/opt+0x73e01ca)
llvm#16 0x000058ee9a0faee0 llvm::LoopVectorizationLegality::isVectorizableEarlyExitLoop() (/usr/local/bin/opt+0x73e0ee0)
llvm#17 0x000058ee9a104678 llvm::LoopVectorizationLegality::canVectorize(bool) (/usr/local/bin/opt+0x73ea678)
llvm#18 0x000058ee9a08c953 llvm::LoopVectorizePass::processLoop(llvm::Loop*) (/usr/local/bin/opt+0x7372953)
llvm#19 0x000058ee9a090e21 llvm::LoopVectorizePass::runImpl(llvm::Function&) (/usr/local/bin/opt+0x7376e21)
llvm#20 0x000058ee9a0914e0 llvm::LoopVectorizePass::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/usr/local/bin/opt+0x73774e0)
llvm#21 0x000058ee99e419a5 llvm::detail::PassModel<llvm::Function, llvm::LoopVectorizePass, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) PassBuilderPipelines.cpp:0:0
llvm#22 0x000058ee97f18905 llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/usr/local/bin/opt+0x51fe905)
llvm#23 0x000058ee995d70d5 llvm::detail::PassModel<llvm::Function, llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) AMDGPUTargetMachine.cpp:0:0
llvm#24 0x000058ee97f17051 llvm::ModuleToFunctionPassAdaptor::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/usr/local/bin/opt+0x51fd051)
llvm#25 0x000058ee995d7775 llvm::detail::PassModel<llvm::Module, llvm::ModuleToFunctionPassAdaptor, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) AMDGPUTargetMachine.cpp:0:0
llvm#26 0x000058ee97f1783d llvm::PassManager<llvm::Module, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/usr/local/bin/opt+0x51fd83d)
llvm#27 0x000058ee9c153909 llvm::runPassPipeline(llvm::StringRef, llvm::Module&, llvm::TargetMachine*, llvm::TargetLibraryInfoImpl*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::StringRef, llvm::ArrayRef<llvm::PassPlugin>, llvm::ArrayRef<std::function<void (llvm::PassBuilder&)>>, llvm::opt_tool::OutputKind, llvm::opt_tool::VerifierKind, bool, bool, bool, bool, bool, bool, bool, bool) (/usr/local/bin/opt+0x9439909)
llvm#28 0x000058ee97c3f380 optMain (/usr/local/bin/opt+0x4f25380)
llvm#29 0x00007c49d4c2a1ca __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:74:3
llvm#30 0x00007c49d4c2a28b call_init ./csu/../csu/libc-start.c:128:20
llvm#31 0x00007c49d4c2a28b __libc_start_main ./csu/../csu/libc-start.c:347:5
llvm#32 0x000058ee97c309a5 _start (/usr/local/bin/opt+0x4f169a5)
```

This is caused by a type mismatch between
`SE.getSCEV(DerefRK.IRArgValue)` and `DerefBytesSCEV`.
Fixing this by extending them to the wider type.
cenewcombe pushed a commit that referenced this pull request Apr 9, 2026
Running gcc test c-c++-common/tsan/tls_race.c on s390 we get:

ThreadSanitizer: CHECK failed: tsan_platform_linux.cpp:618 "((thr_beg))
>= ((tls_addr))" (0x3ffaa35e140, 0x3ffaa35e250) (tid=2419930)
#0 __tsan::CheckUnwind() /devel/src/libsanitizer/tsan/tsan_rtl.cpp:696
(libtsan.so.2+0x91b57)
#1 __sanitizer::CheckFailed(char const*, int, char const*, unsigned long
long, unsigned long long)
/devel/src/libsanitizer/sanitizer_common/sanitizer_termination.cpp:86
(libtsan.so.2+0xd211b)
#2 __tsan::ImitateTlsWrite(__tsan::ThreadState*, unsigned long, unsigned
long) /devel/src/libsanitizer/tsan/tsan_platform_linux.cpp:618
(libtsan.so.2+0x8faa3)
llvm#3 __tsan::ThreadStart(__tsan::ThreadState*, unsigned int, unsigned long
long, __sanitizer::ThreadType)
/devel/src/libsanitizer/tsan/tsan_rtl_thread.cpp:225
(libtsan.so.2+0xaadb5)
llvm#4 __tsan_thread_start_func
/devel/src/libsanitizer/tsan/tsan_interceptors_posix.cpp:1065
(libtsan.so.2+0x3d34d)
llvm#5 start_thread <null> (libc.so.6+0xae70d) (BuildId:
d3b08de1b543c2d15d419bf861b3c2e4c01ac75b)
llvm#6 thread_start <null> (libc.so.6+0x12d2ff) (BuildId:
d3b08de1b543c2d15d419bf861b3c2e4c01ac75b)

In order to determine the static TLS blocks in GetStaticTlsBoundary we
iterate over the modules and try to find the largest range without a
gap. Here we might have that modules are spaced exactly by the
alignment. For example, for the failing test we have:

(gdb) p/x ranges.data_[0]
$1 = {begin = 0x3fff7f9e6b8, end = 0x3fff7f9e740, align = 0x8, tls_modid
= 0x3} (gdb) p/x ranges.data_[1]
$2 = {begin = 0x3fff7f9e740, end = 0x3fff7f9eed0, align = 0x40,
tls_modid = 0x2} (gdb) p/x ranges.data_[2]
$3 = {begin = 0x3fff7f9eed8, end = 0x3fff7f9eef8, align = 0x8, tls_modid
= 0x4} (gdb) p/x ranges.data_[3]
$4 = {begin = 0x3fff7f9eefc, end = 0x3fff7f9ef00, align = 0x4, tls_modid
= 0x1}

where ranges[3].begin == ranges[2].end + ranges[3].align holds. Since in
the loop a strict inequality test is used we compute the wrong address

(gdb) p/x *addr
$5 = 0x3fff7f9eefc

whereas 0x3fff7f9e6b8 is expected which is why we bail out in the
subsequent.
cenewcombe pushed a commit that referenced this pull request Apr 13, 2026
…8271)

Example:

    int foo(int a, int b) { return a - 1 + ~b; }

Before, on AArch64:

    mvn w8, w1
    add w8, w0, w8
    sub w0, w8, #1

After (matches gcc):

    sub w0, w0, w1
    sub w0, w0, #2

Proof: https://alive2.llvm.org/ce/z/g_bV01
cenewcombe pushed a commit that referenced this pull request Apr 17, 2026
…bols add' (llvm#188377)

Context: 
lldb might crash when running to a debuggee crashing state and do a
target symbols add command.
Backtrace: 
```
 #0 0x000055ca6790dc65 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) /home/hyubo/osmeta/external/llvm-project/llvm/lib/Support/Unix/Signals.inc:848:11
 #1 0x000055ca6790e434 PrintStackTraceSignalHandler(void*) /home/hyubo/osmeta/external/llvm-project/llvm/lib/Support/Unix/Signals.inc:931:1
 #2 0x000055ca6790b839 llvm::sys::RunSignalHandlers() /home/hyubo/osmeta/external/llvm-project/llvm/lib/Support/Signals.cpp:104:5
 llvm#3 0x000055ca6790ff6b SignalHandler(int, siginfo_t*, void*) /home/hyubo/osmeta/external/llvm-project/llvm/lib/Support/Unix/Signals.inc:430:38
 llvm#4 0x00007fe9e5e44560 __restore_rt /home/engshare/third-party2/glibc/2.34/src/glibc-2.34/signal/../sysdeps/unix/sysv/linux/libc_sigaction.c:13:0
 llvm#5 0x00007fe9e5f25649 syscall /home/engshare/third-party2/glibc/2.34/src/glibc-2.34/misc/../sysdeps/unix/sysv/linux/x86_64/syscall.S:38:0
 llvm#6 0x00007fe9ec649170 SignalHandler(int, siginfo_t*, void*) /home/hyubo/osmeta/external/llvm-project/llvm/lib/Support/Unix/Signals.inc:429:7
 llvm#7 0x00007fe9e5e44560 __restore_rt /home/engshare/third-party2/glibc/2.34/src/glibc-2.34/signal/../sysdeps/unix/sysv/linux/libc_sigaction.c:13:0
 llvm#8 0x00007fe9ebb77bf0 lldb_private::operator<(lldb_private::StackID const&, lldb_private::StackID const&) /home/hyubo/osmeta/external/llvm-project/lldb/source/Target/StackID.cpp:99:16
 llvm#9 0x00007fe9ebb6863d CompareStackID(std::shared_ptr<lldb_private::StackFrame> const&, lldb_private::StackID const&) /home/hyubo/osmeta/external/llvm-project/lldb/source/Target/StackFrameList.cpp:683:3
llvm#10 0x00007fe9ebb6d049 bool __gnu_cxx::__ops::_Iter_comp_val<bool (*)(std::shared_ptr<lldb_private::StackFrame> const&, lldb_private::StackID const&)>::operator()<__gnu_cxx::__normal_iterator<std::shared_ptr<lldb_private::StackFrame>*, std::vector<std::shared_ptr<lldb_private::StackFrame>, std::allocator<std::shared_ptr<lldb_private::StackFrame>>>>, lldb_private::StackID const>(__gnu_cxx::__normal_iterator<std::shared_ptr<lldb_private::StackFrame>*, std::vector<std::shared_ptr<lldb_private::StackFrame>, std::allocator<std::shared_ptr<lldb_private::StackFrame>>>>, lldb_private::StackID const&) /mnt/gvfs/third-party2/libgcc/d1129753c8361ac8e9453c0f4291337a4507ebe6/11.x/platform010/5684a5a/include/c++/11.x/bits/predefined_ops.h:196:4
llvm#11 0x00007fe9ebb6cefe __gnu_cxx::__normal_iterator<std::shared_ptr<lldb_private::StackFrame>*, std::vector<std::shared_ptr<lldb_private::StackFrame>, std::allocator<std::shared_ptr<lldb_private::StackFrame>>>> std::__lower_bound<__gnu_cxx::__normal_iterator<std::shared_ptr<lldb_private::StackFrame>*, std::vector<std::shared_ptr<lldb_private::StackFrame>, std::allocator<std::shared_ptr<lldb_private::StackFrame>>>>, lldb_private::StackID, __gnu_cxx::__ops::_Iter_comp_val<bool (*)(std::shared_ptr<lldb_private::StackFrame> const&, lldb_private::StackID const&)>>(__gnu_cxx::__normal_iterator<std::shared_ptr<lldb_private::StackFrame>*, std::vector<std::shared_ptr<lldb_private::StackFrame>, std::allocator<std::shared_ptr<lldb_private::StackFrame>>>>, __gnu_cxx::__normal_iterator<std::shared_ptr<lldb_private::StackFrame>*, std::vector<std::shared_ptr<lldb_private::StackFrame>, std::allocator<std::shared_ptr<lldb_private::StackFrame>>>>, lldb_private::StackID const&, __gnu_cxx::__ops::_Iter_comp_val<bool (*)(std::shared_ptr<lldb_private::StackFrame> const&, lldb_private::StackID const&)>) /mnt/gvfs/third-party2/libgcc/d1129753c8361ac8e9453c0f4291337a4507ebe6/11.x/platform010/5684a5a/include/c++/11.x/bits/stl_algobase.h:1464:8
llvm#12 0x00007fe9ebb6cdfc __gnu_cxx::__normal_iterator<std::shared_ptr<lldb_private::StackFrame>*, std::vector<std::shared_ptr<lldb_private::StackFrame>, std::allocator<std::shared_ptr<lldb_private::StackFrame>>>> std::lower_bound<__gnu_cxx::__normal_iterator<std::shared_ptr<lldb_private::StackFrame>*, std::vector<std::shared_ptr<lldb_private::StackFrame>, std::allocator<std::shared_ptr<lldb_private::StackFrame>>>>, lldb_private::StackID, bool (*)(std::shared_ptr<lldb_private::StackFrame> const&, lldb_private::StackID const&)>(__gnu_cxx::__normal_iterator<std::shared_ptr<lldb_private::StackFrame>*, std::vector<std::shared_ptr<lldb_private::StackFrame>, std::allocator<std::shared_ptr<lldb_private::StackFrame>>>>, __gnu_cxx::__normal_iterator<std::shared_ptr<lldb_private::StackFrame>*, std::vector<std::shared_ptr<lldb_private::StackFrame>, std::allocator<std::shared_ptr<lldb_private::StackFrame>>>>, lldb_private::StackID const&, bool (*)(std::shared_ptr<lldb_private::StackFrame> const&, lldb_private::StackID const&)) /mnt/gvfs/third-party2/libgcc/d1129753c8361ac8e9453c0f4291337a4507ebe6/11.x/platform010/5684a5a/include/c++/11.x/bits/stl_algo.h:2062:14
llvm#13 0x00007fe9ebb685fa auto llvm::lower_bound<std::vector<std::shared_ptr<lldb_private::StackFrame>, std::allocator<std::shared_ptr<lldb_private::StackFrame>>>&, lldb_private::StackID const&, bool (*)(std::shared_ptr<lldb_private::StackFrame> const&, lldb_private::StackID const&)>(std::vector<std::shared_ptr<lldb_private::StackFrame>, std::allocator<std::shared_ptr<lldb_private::StackFrame>>>&, lldb_private::StackID const&, bool (*)(std::shared_ptr<lldb_private::StackFrame> const&, lldb_private::StackID const&)) /home/hyubo/osmeta/external/llvm-project/llvm/include/llvm/ADT/STLExtras.h:2001:10
llvm#14 0x00007fe9ebb68441 lldb_private::StackFrameList::GetFrameWithStackID(lldb_private::StackID const&) /home/hyubo/osmeta/external/llvm-project/lldb/source/Target/StackFrameList.cpp:697:11
llvm#15 0x00007fe9ebbee395 lldb_private::Thread::GetFrameWithStackID(lldb_private::StackID const&) /home/hyubo/osmeta/external/llvm-project/lldb/include/lldb/Target/Thread.h:459:7
llvm#16 0x00007fe9ebac7cf7 lldb_private::ExecutionContextRef::GetFrameSP() const /home/hyubo/osmeta/external/llvm-project/lldb/source/Target/ExecutionContext.cpp:643:25
llvm#17 0x00007fe9ebac80e1 lldb_private::GetStoppedExecutionContext(lldb_private::ExecutionContextRef const*) /home/hyubo/osmeta/external/llvm-project/lldb/source/Target/ExecutionContext.cpp:164:34
llvm#18 0x00007fe9eb8903fa lldb_private::Statusline::Redraw(std::optional<lldb_private::ExecutionContextRef>) /home/hyubo/osmeta/external/llvm-project/lldb/source/Core/Statusline.cpp:139:7
llvm#19 0x00007fe9eb7ac8be lldb_private::Debugger::RedrawStatusline(std::optional<lldb_private::ExecutionContextRef>) /home/hyubo/osmeta/external/llvm-project/lldb/source/Core/Debugger.cpp:1233:3
llvm#20 0x00007fe9eb804d1e lldb_private::IOHandlerEditline::RedrawCallback() /home/hyubo/osmeta/external/llvm-project/lldb/source/Core/IOHandler.cpp:446:3
llvm#21 0x00007fe9eb80aa81 lldb_private::IOHandlerEditline::IOHandlerEditline(lldb_private::Debugger&, lldb_private::IOHandler::Type, std::shared_ptr<lldb_private::File> const&, std::shared_ptr<lldb_private::LockableStreamFile> const&, std::shared_ptr<lldb_private::LockableStreamFile> const&, unsigned int, char const*, llvm::StringRef, llvm::StringRef, bool, bool, unsigned int, lldb_private::IOHandlerDelegate&)::$_2::operator()() const /home/hyubo/osmeta/external/llvm-project/lldb/source/Core/IOHandler.cpp:262:73
llvm#22 0x00007fe9eb80aa5d void llvm::detail::UniqueFunctionBase<void>::CallImpl<lldb_private::IOHandlerEditline::IOHandlerEditline(lldb_private::Debugger&, lldb_private::IOHandler::Type, std::shared_ptr<lldb_private::File> const&, std::shared_ptr<lldb_private::LockableStreamFile> const&, std::shared_ptr<lldb_private::LockableStreamFile> const&, unsigned int, char const*, llvm::StringRef, llvm::StringRef, bool, bool, unsigned int, lldb_private::IOHandlerDelegate&)::$_2>(void*) /home/hyubo/osmeta/external/llvm-project/llvm/include/llvm/ADT/FunctionExtras.h:213:5
llvm#23 0x00007fe9eb93bfbf llvm::unique_function<void ()>::operator()() /home/hyubo/osmeta/external/llvm-project/llvm/include/llvm/ADT/FunctionExtras.h:365:5
llvm#24 0x00007fe9eb93bb80 lldb_private::Editline::GetCharacter(wchar_t*) /home/hyubo/osmeta/external/llvm-project/lldb/source/Host/common/Editline.cpp:0:5
llvm#25 0x00007fe9eb941a18 lldb_private::Editline::ConfigureEditor(bool)::$_0::operator()(editline*, wchar_t*) const /home/hyubo/osmeta/external/llvm-project/lldb/source/Host/common/Editline.cpp:1287:5
llvm#26 0x00007fe9eb9419e2 lldb_private::Editline::ConfigureEditor(bool)::$_0::__invoke(editline*, wchar_t*) /home/hyubo/osmeta/external/llvm-project/lldb/source/Host/common/Editline.cpp:1286:27
llvm#27 0x00007fe9f3384e26 el_getc /home/engshare/third-party2/libedit/3.1/src/libedit/src/read.c:439:14
llvm#28 0x00007fe9f3384e26 el_getc /home/engshare/third-party2/libedit/3.1/src/libedit/src/read.c:400:1
llvm#29 0x00007fe9f3384f90 read_getcmd /home/engshare/third-party2/libedit/3.1/src/libedit/src/read.c:247:14
llvm#30 0x00007fe9f3384f90 el_gets /home/engshare/third-party2/libedit/3.1/src/libedit/src/read.c:586:14
llvm#31 0x00007fe9eb9409f3 lldb_private::Editline::GetLine(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>&, bool&) /home/hyubo/osmeta/external/llvm-project/lldb/source/Host/common/Editline.cpp:1636:16
llvm#32 0x00007fe9eb8044d7 lldb_private::IOHandlerEditline::GetLine(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>&, bool&) /home/hyubo/osmeta/external/llvm-project/lldb/source/Core/IOHandler.cpp:339:5
llvm#33 0x00007fe9eb805609 lldb_private::IOHandlerEditline::Run() /home/hyubo/osmeta/external/llvm-project/lldb/source/Core/IOHandler.cpp:600:11
llvm#34 0x00007fe9eb7b214c lldb_private::Debugger::RunIOHandlers() /home/hyubo/osmeta/external/llvm-project/lldb/source/Core/Debugger.cpp:1280:16
llvm#35 0x00007fe9eb98f00f lldb_private::CommandInterpreter::RunCommandInterpreter(lldb_private::CommandInterpreterRunOptions&) /home/hyubo/osmeta/external/llvm-project/lldb/source/Interpreter/CommandInterpreter.cpp:3620:16
llvm#36 0x00007fe9eb4f0e09 lldb::SBDebugger::RunCommandInterpreter(bool, bool) /home/hyubo/osmeta/external/llvm-project/lldb/source/API/SBDebugger.cpp:1234:42
llvm#37 0x000055ca6788d6b0 Driver::MainLoop() /home/hyubo/osmeta/external/llvm-project/lldb/tools/driver/Driver.cpp:677:3
llvm#38 0x000055ca6788e226 main /home/hyubo/osmeta/external/llvm-project/lldb/tools/driver/Driver.cpp:887:17
llvm#39 0x00007fe9e5e2c657 __libc_start_call_main /home/engshare/third-party2/glibc/2.34/src/glibc-2.34/csu/../sysdeps/nptl/libc_start_call_main.h:58:16
llvm#40 0x00007fe9e5e2c718 call_init /home/engshare/third-party2/glibc/2.34/src/glibc-2.34/csu/../csu/libc-start.c:128:20
llvm#41 0x00007fe9e5e2c718 __libc_start_main@GLIBC_2.2.5 /home/engshare/third-party2/glibc/2.34/src/glibc-2.34/csu/../csu/libc-start.c:379:5
llvm#42 0x000055ca67889a11 _start /home/engshare/third-party2/glibc/2.34/src/glibc-2.34/csu/../sysdeps/x86_64/start.S:118:0
Segmentation fault (core dumped)
```

When `target symbols add` is run, `Symtab::AddSymbol()` can reallocate
the underlying `std::vector<Symbol>` and resize it, invalidating all
existing Symbol* pointers. While `Process::Flush()` clears stale stack
frames, the statusline caches its own `ExecutionContextRef` containing a
`StackID` with a `SymbolContextScope*` (which can be a `Symbol*`). This
cached reference is not cleared by `Process::Flush()`, so the next
statusline redraw accesses a dangling pointer and crashes.

Fix this by adding `Statusline::Flush()` which clears the cached frame,
`Debugger::Flush()` which forwards to it under the statusline mutex, and
calling `Debugger::Flush()` from `Process::Flush()` so that all flush
paths (symbol add, exec, module load) also invalidate the statusline's
stale state.

After this fix, lldb is not crashing anymore, new symbols from a symbol
file are correctly loaded

---------

Co-authored-by: George Hu <georgehuyubo@gmail.com>
cenewcombe pushed a commit that referenced this pull request Apr 23, 2026
When Control Flow Integrity (CFI) is enabled, jump tables are used to
redirect indirect calls. Previously, these jump table entries lacked
debug information, making it difficult for profilers and debuggers to
attribute execution time correctly.

Now stack trace, when stopped on jump table entry will looks like this:
```
#0: __ubsan_check_cfi_icall_jt at sanitizer/ubsan_interface.h:0
#1: c::c() (.cfi_jt) at sanitizer/ubsan_interface.h:0:0
#2: .cfi.jumptable.81 at sanitizer/ubsan_interface.h:0:0
```
cenewcombe pushed a commit that referenced this pull request Apr 23, 2026
…93670)

When Control Flow Integrity (CFI) is enabled, jump tables are used to
redirect indirect calls. Previously, these jump table entries lacked
debug information, making it difficult for profilers and debuggers to
attribute execution time correctly.

Now stack trace, when stopped on jump table entry will looks like this:
```
#0: __ubsan_check_cfi_icall_jt at sanitizer/ubsan_interface.h:0
#1: c::c() (.cfi_jt) at sanitizer/ubsan_interface.h:0:0
#2: .cfi.jumptable.81 at sanitizer/ubsan_interface.h:0:0
```

This is reland of llvm#192736, reverted with llvm#193663.
This version don't update debug info for "Cross-DSO CFI" mode.
cenewcombe pushed a commit that referenced this pull request Apr 27, 2026
llvm#184115)

In this change I'm extending the "memory region" command to show users
the
overlay permissions that a protection key refers to, and the result of
applying that overlay to the page table permissions.

For example, protection key 0 refers to Perm0 in the por register.
```
(lldb) register read por 
             Perm0 = Read, Write, Execute
```
This is the default key, so many regions use it. 
```
(lldb) memory region --all
<...>
[0x000ffffff7db0000-0x000ffffff7f40000) r-x /usr/lib/aarch64-linux-gnu/libc.so.6 PT_LOAD[0]
protection key: 0 (rwx, effective: r-x)
```
Protection keys can only change what was already enabled in the 
page table. So we start with read and execute. Then a read/write/execute
overlay
is applied. We cannot add write, so the result is read and execute.

Here's an example of its use with a real crash (output edited):
```
(lldb) c
* thread #1, name = 'test.o', stop reason = signal SIGSEGV: failed protection key checks (fault address=0xffffff7d60000)
-> 106    read_only_page[0] = '?';
(lldb) memory region 0xffffff7d60000
[0x000ffffff7d60000-0x000ffffff7d70000) rw- 
protection key: 6 (r--, effective: r--)
(lldb) register read por 
             Perm6 = Read
```
The calculation of permissions is implemented by a new ABI method.
It's in ABI for 2 reasons:
* These overlays are usually in a register (X86 and AArch64 are)
  and that register name is architecture specific.
* The way the overlay values apply may differ between architecture.
  AArch64 treats a set bit as adding a permission, but some may 
  treat it as removing.

Technically this is dependent on operating system and architecture.
However, so are the methods for removing non-address bits, and those
are in ABI too.

To test this I have changed the allocations in the test program
to use read+execute permissions by default. With read+write+execute
I could not observe that the overlay only changes enabled permissions.
cenewcombe pushed a commit that referenced this pull request Apr 27, 2026
We did not initialize the out parameters in llvm#192347, causing the
"sanitizer-x86_64-linux-fast" bot to complain with:

```
SUMMARY: MemorySanitizer: use-of-uninitialized-value /home/b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/lib/Frontend/CompilerInstance.cpp:1525:63 in compileModuleImpl(clang::CompilerInstance&, clang::SourceLocation, clang::SourceLocation, clang::Module*, clang::ModuleFileName)
Exiting
==clang==3084515==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0x586360f7a604 in compileModuleImpl(clang::CompilerInstance&, clang::SourceLocation, clang::SourceLocation, clang::Module*, clang::ModuleFileName) /home/b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/lib/Frontend/CompilerInstance.cpp:1525:63
    #1 <...>
```

This PR should fix that.
cenewcombe pushed a commit that referenced this pull request Apr 27, 2026
…lvm#141480)

When a vector integer-to-float conversion is followed by a multiply with a
reciprocal power-of-two constant, we can fold both operations into a single
SCVTF or UCVTF instruction with a fixed-point shift operand.

For example, `fmul(sitofp(v2i32 x), <0.5, 0.5>)` becomes `scvtf.2s v0, v0, #1`.

This is a reworked version with several improvements over the original
submission:
- Rewrite the C++ operand matcher to share implementation with the existing
    `SelectCVTFixedPointVec` (MOVIshift, FMOV, and DUP handling with correct
    truncation for f16)
- Add `uitofp`/`ucvtf` patterns via a `CVTFRecipPat` multiclass
- Add full GlobalISel support (`GIComplexOperandMatcher` + renderer)

Supported vector types: `v2f32`, `v4f32`, `v2f64`, `v4f16`, `v8f16`.

Fixes llvm#94909
cenewcombe pushed a commit that referenced this pull request May 18, 2026
llvm#183506 revealed a pre-existing
use-after-scope in createInstrInfo (MSan bot:
https://lab.llvm.org/buildbot/#/builders/164/builds/21562 [*]).

This patch fixes the issue by changing the stack-allocated
AArch64Subtarget (which goes out of scope once createInstrInfo()
returns) into heap-allocated, allowing it to be safely stored in the
returned AArch64InstrInfo.

-----

[*] WARNING: MemorySanitizer: use-of-uninitialized-value
#0 0x55555666fabd in
llvm::AArch64InstrInfo::getInstSizeInBytes(llvm::MachineInstr const&)
const
/home/b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp:247:5
...

/home/b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/llvm/unittests/Target/AArch64/InstSizes.cpp:85:3
llvm#9 0x555556508559 in InstSizes_MOVaddrTagged_Test::TestBody()
/home/b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/llvm/unittests/Target/AArch64/InstSizes.cpp:301:3
...

  Member fields were destroyed
#0 0x555556498a1d in __sanitizer_dtor_callback_fields
/home/b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/compiler-rt/lib/msan/msan_interceptors.cpp:1074:5
#1 0x5555564fbda6 in ~Triple
/home/b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/llvm/include/llvm/TargetParser/Triple.h:348:12
#2 0x5555564fbda6 in ~Triple
/home/b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/llvm/include/llvm/TargetParser/Triple.h:47:7
llvm#3 0x5555564fbda6 in llvm::AArch64Subtarget::~AArch64Subtarget()
/home/b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/llvm/lib/Target/AArch64/AArch64Subtarget.h:38:7
llvm#4 0x555556503396 in (anonymous
namespace)::createInstrInfo(llvm::TargetMachine*)
/home/b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/llvm/unittests/Target/AArch64/InstSizes.cpp:38:1
llvm#5 0x5555565084cb in InstSizes_MOVaddrTagged_Test::TestBody()
/home/b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/llvm/unittests/Target/AArch64/InstSizes.cpp:299:42
cenewcombe pushed a commit that referenced this pull request May 21, 2026
…198548)

When an MCP client disconnects (EOF), `IOTransport::OnRead` called
`handler.OnClosed()` before resetting `m_read_handle`. The MCP server's
`OnClosed` handler erases the client from `m_instances`, destroying both
  the transport (`this`) and the binder (`handler`). The subsequent
`m_read_handle.reset()` then accessed the destroyed transport's member,
  causing a use-after-free (SIGSEGV).

* thread #1, stop reason = signal SIGSEGV: address not mapped to object
(fault address=0x28)
* frame #0: 0x00007ff5d4d5afda
liblldb.so.23.2`lldb_private::transport::IOTransport<lldb_protocol::mcp::ProtocolDescriptor>::OnRead(lldb_private::MainLoopBase&,
lldb_private::transport::JSONTransport<lldb_protocol::mcp::ProtocolDescriptor>::MessageHandler&)
+ 1274
frame #1: 0x00007ff5d1140ad8
liblldb.so.23.0`lldb_private::MainLoopPosix::Run() + 408
frame #2: 0x00007ff5d1760c1c
liblldb.so.23.0`std::thread::_State_impl<std::thre

  Fix by resetting the read handle before calling `OnClosed()`, so no
  transport members are accessed after the handler potentially destroys
  the transport.

Then when the scope is left, the destructor is called for the new
read_handle local variable and it is cleaned up.

New unit tests added that fail without this change. With the change, the
custom 'ai' script (allows end user locally to communicate lldb context
to agent backend via a spun up MCP server: "protocol-server start MCP
listen://localhost:{port}") now successfully concludes without this
crash

Assisted with: claude
cenewcombe pushed a commit that referenced this pull request Jun 16, 2026
…ructions (llvm#185170)

We currently emit `movi`+`ext` instructions when generating code for
shuffle slides of a 64-bit vector left/right and fill it with zeros.
This patch optimizes these patterns to use a single `ushr`/`shl`
instruction instead.

Example:
```llvm
  define <8 x i8> @slide_left(<8 x i8> %v) {
    %r = shufflevector <8 x i8> %v, <8 x i8> zeroinitializer,
         <8 x i32> <i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8>
    ret <8 x i8> %r
  }
```

Before, we generate:
```
  movi    v1.2d, #0
  ext     v0.8b, v0.8b, v1.8b, #1
```

Now:
```
  ushr    d0, d0, llvm#8
```

Fixes: llvm#183398
Alive2 proof: https://alive2.llvm.org/ce/z/QaW5CQ

---------

Signed-off-by: Dibri Nsofor <dibrinsofor@gmail.com>
cenewcombe pushed a commit that referenced this pull request Jun 26, 2026
…m#204601)

When creating the new intrinsic declaration, use the correct pointer
argument (arg #1) from the existing call. Currently, we use arg #0
(size) and end up creating an invalid intrinsic declaration. However,
later on we do not use this declaration directly and instead call
`CreateLifetimeStart` or `CreateLifetimeEnd` IRBuilder functions that
end up creating valid intrinsic declarations. The net result is that we
are left with a stray unused invalid declaration.

Fix this issue by creating the intrinsic with the right pointer argument
type.
cenewcombe pushed a commit that referenced this pull request Jul 6, 2026
…lvm#191275)" (llvm#206816)

This reverts commit 0f51760.

A test fails with the commit
(llvm#191275 (comment)):

```
Traceback (most recent call last):
  File "/home/tcwg-buildbot/worker/lldb-aarch64-ubuntu/llvm-project/lldb/test/API/functionalities/scripted_frame_provider/TestScriptedFrameProvider.py", line 596, in test_python_source_frames
    self.assertNotIn("0xffffffffffffffff", output.lower())
AssertionError: '0xffffffffffffffff' unexpectedly found in "* thread #2, name = 'a.out', stop reason = breakpoint 1.1\n  * frame #0: compute_fibonacci at python_helper.py:7 [synthetic]\n    frame #1: process_data at python_helper.py:16 [synthetic]\n    frame #2: main at python_helper.py:27 [synthetic]\n    frame llvm#3: 0x0000badc2de81358 a.out`thread_func(thread_num=0) at main.cpp:44:13\n    frame llvm#4: 0x0000badc2de81f9c a.out`void std::__invoke_impl<void, void (*)(int), int>((null)=__invoke_other @ 0x0000f1555ebae74f, __f=0x0000badc66845ec0, __args=0x0000badc66845eb8) at invoke.h:61:14\n    frame llvm#5: 0x0000badc2de81f18 a.out`std::__invoke_result<void (*)(int), int>::type std::__invoke<void (*)(int), int>(__fn=0x0000badc66845ec0, __args=0x0000badc66845eb8) at invoke.h:96:14\n    frame llvm#6: 0x0000badc2de81ee4 a.out`void std::thread::_invoker<std::tuple<void (*)(int), int>>::_m_invoke<0ul, 1ul>(this=0x0000badc66845eb8, (null)=_index_tuple<0ul, 1ul> @ 0x0000f1555ebae7af) at std_thread.h:259:13\n    frame llvm#7: 0x0000badc2de81e98 a.out`std::thread::_invoker<std::tuple<void (*)(int), int>>::operator()(this=0x0000badc66845eb8) at std_thread.h:266:11\n    frame llvm#8: 0x0000badc2de81d70 a.out`std::thread::_state_impl<std::thread::_invoker<std::tuple<void (*)(int), int>>>::_m_run(this=0xffffffffffffffff) at std_thread.h:211:13\n    frame llvm#9: 0x0000f1555ef029cc libstdc++.so.6`___lldb_unnamed_symbol_d29b0 + 28\n    frame llvm#10: 0x0000f1555ec30398 libc.so.6`___lldb_unnamed_symbol_800c0 + 728\n    frame llvm#11: 0x0000f1555ec99e9c libc.so.6`___lldb_unnamed_symbol_e9e90 + 12\n"
```

I don't know why this test fails with the PR, but I don't have time to
fix it now, so revert it to unblock CI.

The backtrace was
```
    frame #0: compute_fibonacci at python_helper.py:7 [synthetic]
    frame #1: process_data at python_helper.py:16 [synthetic]
    frame #2: main at python_helper.py:27 [synthetic]
    frame llvm#3: 0x0000badc2de81358 a.out`thread_func(thread_num=0) at main.cpp:44:13
    frame llvm#4: 0x0000badc2de81f9c a.out`void std::__invoke_impl<void, void (*)(int), int>((null)=__invoke_other @ 0x0000f1555ebae74f, __f=0x0000badc66845ec0, __args=0x0000badc66845eb8) at invoke.h:61:14
    frame llvm#5: 0x0000badc2de81f18 a.out`std::__invoke_result<void (*)(int), int>::type std::__invoke<void (*)(int), int>(__fn=0x0000badc66845ec0, __args=0x0000badc66845eb8) at invoke.h:96:14
    frame llvm#6: 0x0000badc2de81ee4 a.out`void std::thread::_invoker<std::tuple<void (*)(int), int>>::_m_invoke<0ul, 1ul>(this=0x0000badc66845eb8, (null)=_index_tuple<0ul, 1ul> @ 0x0000f1555ebae7af) at std_thread.h:259:13
    frame llvm#7: 0x0000badc2de81e98 a.out`std::thread::_invoker<std::tuple<void (*)(int), int>>::operator()(this=0x0000badc66845eb8) at std_thread.h:266:11
    frame llvm#8: 0x0000badc2de81d70 a.out`std::thread::_state_impl<std::thread::_invoker<std::tuple<void (*)(int), int>>>::_m_run(this=0xffffffffffffffff) at std_thread.h:211:13
    frame llvm#9: 0x0000f1555ef029cc libstdc++.so.6`___lldb_unnamed_symbol_d29b0 + 28
    frame llvm#10: 0x0000f1555ec30398 libc.so.6`___lldb_unnamed_symbol_800c0 + 728
    frame llvm#11: 0x0000f1555ec99e9c libc.so.6`___lldb_unnamed_symbol_e9e90 + 12
```

This contains 0xffffffffffffffff in frame 8.
cenewcombe pushed a commit that referenced this pull request Jul 6, 2026
Summary

This builds on the accelerator plugin protocol
(llvm#201489) by letting a plugin
ask the client to create and connect a second
target — the mechanism a real backend (e.g. a GPU debug stub) uses to
surface
  the accelerator alongside the CPU process being debugged.

  ### What this adds

**Protocol** — a new `AcceleratorConnectionInfo` describing how the
client
  should bring up the accelerator target.

  **Client** — when an `AcceleratorActions` carries `connect_info`,
`ProcessGDBRemote` creates a new (empty) target, reverse-connects it to
the GDB
  server the plugin points.

  **Mock server (for testing)** — to exercise this end to end, the mock
accelerator plugin stands up an in-process GDB server backed by a
minimal fake
process: `ProcessMockAccelerator`, `ThreadMockAccelerator` and
`RegisterContextMockAccelerator`.

  ### Scope

Intentionally minimal: the goal is to create and show the second
(accelerator)
target. There is no register/memory modeling beyond what a connection
requires. Next set of PRs will build up on this.

  ### Testing


Demo of how this looks with this PR. (explicitly asking the native
process to stop at every breakpoint for testability)

```
satyajanga@devgpu011:toolchain $ ./bin/lldb
(lldb) file /home/satyajanga/llvm-sand/build/Debug/fbcode-x86_64/toolchain/lldb-test-build.noindex/accelerator/mock/TestMockAcceleratorActions/a.out                                     Current executable set to '/home/satyajanga/llvm-sand/build/Debug/fbcode-x86_64/toolchain/lldb-test-build.noindex/accelerator/mock/TestMockAcceleratorActions/a.out' (x86_64).
(lldb) log enable -f /tmp/packets.log gdb-remote packets                                                                                                                                 (lldb) r
Process 1430531 launched: '/home/satyajanga/llvm-sand/build/Debug/fbcode-x86_64/toolchain/lldb-test-build.noindex/accelerator/mock/TestMockAcceleratorActions/a.out' (x86_64)
Process 1430531 stopped
(lldb) target list
Current targets:
* target #0: /home/satyajanga/llvm-sand/build/Debug/fbcode-x86_64/toolchain/lldb-test-build.noindex/accelerator/mock/TestMockAcceleratorActions/a.out ( arch=x86_64-unknown-linux-gnu, platform=host, pid=1430531, state=stopped )
(lldb) c
Process 1430531 resuming
Process 1 stopped
* thread #1, name = 'Mock Accelerator Thread', stop reason = trace
       frame #0: 0x0000000000001004
error: memory read failed for 0x1000
Target 0: (a.out) stopped.
(lldb) target list
Current targets:
  target #0: /home/satyajanga/llvm-sand/build/Debug/fbcode-x86_64/toolchain/lldb-test-build.noindex/accelerator/mock/TestMockAcceleratorActions/a.out ( arch=x86_64-unknown-linux-gnu, platform=host, pid=1430531, state=stopped )
* target #1: <none> ( arch=x86_64-unknown-linux-gnu, platform=host, pid=1, state=stopped )
(lldb) c
Process 1 resuming
(lldb) target select 0
Current targets:
* target #0: /home/satyajanga/llvm-sand/build/Debug/fbcode-x86_64/toolchain/lldb-test-build.noindex/accelerator/mock/TestMockAcceleratorActions/a.out ( arch=x86_64-unknown-linux-gnu, platform=host, pid=1430531, state=stopped )
  target #1: <none> ( arch=x86_64-unknown-linux-gnu, platform=host, pid=1, state=running )
(lldb) c
Process 1430531 resuming
Process 1430531 stopped
(lldb) target list
Current targets:
* target #0: /home/satyajanga/llvm-sand/build/Debug/fbcode-x86_64/toolchain/lldb-test-build.noindex/accelerator/mock/TestMockAcceleratorActions/a.out ( arch=x86_64-unknown-linux-gnu, platform=host, pid=1430531, state=stopped )
  target #1: <none> ( arch=x86_64-unknown-linux-gnu, platform=host, pid=1, state=running )
(lldb)
a.out │ internal accelerator-plugin (mock) breakpoint(-4).
```

Packet log, 
you can notice the actions set with breakpoint info and later responding
with connection info. and you can also see the 5 GPRs

```
lldb             < 104> send packet: $qSupported:xmlRegisters=i386,arm,mips,arc;multiprocess+;fork-events+;vfork-events+;swbreak+;hwbreak+#cd
lldb             < 299> read packet: $PacketSize=131072;QStartNoAckMode+;qEcho+;native-signals+;QThreadSuffixSupported+;QListThreadsInStopReply+;qXfer:features:read+;QNonStop+;jMultiBreakpoint+;QPassSignals+;qXfer:auxv:read+;qXfer:libraries-svr4:read+;qXfer:siginfo:read+;accelerator-plugins+;multiprocess+;fork-events+;vfork-events+llvm#86
..
lldb             <  32> send packet: $jAcceleratorPluginInitialize#50
lldb             < 238> read packet: $[{"breakpoints":[{"by_address":null,"by_name":{"function_name":"mock_gpu_accelerator_initialize","shlib":null}],"identifier":1,"symbol_names":["mock_gpu_accelerator_compute"]}]],"identifier":1,"plugin_name":"mock","session_name":""}]]#2f
..
intern-state     < 314> send packet: $jAcceleratorPluginBreakpointHit:{"breakpoint":{"by_address":null,"by_name":{"function_name":"mock_gpu_accelerator_initialize","shlib":null}],"identifier":1,"symbol_names":["mock_gpu_accelerator_compute"]}],"plugin_name":"mock","symbol_values":[{"name":"mock_gpu_accelerator_compute","value":93824992235840}]]}]#e7
intern-state     < 487> read packet: ${"actions":{"breakpoints":[{"by_address":null,"by_name":{"function_name":"mock_gpu_accelerator_finish","shlib":"a.out"}],"identifier":3,"symbol_names":[]}],{"by_address":{"load_address":93824992235840}],"by_name":null,"identifier":2,"symbol_names":[]}],{"by_address":null,"by_name":{"function_name":"mock_gpu_accelerator_connect","shlib":null}],"identifier":4,"symbol_names":[]}]],"identifier":2,"plugin_name":"mock","session_name":""}],"auto_resume_native":false,"disable_bp":true}]#7d
..
..
intern-state     < 218> send packet: $jAcceleratorPluginBreakpointHit:{"breakpoint":{"by_address":null,"by_name":{"function_name":"mock_gpu_accelerator_connect","shlib":null}],"identifier":4,"symbol_names":[]}],"plugin_name":"mock","symbol_values":[]}]#d1
intern-state     < 268> read packet: ${"actions":{"breakpoints":[],"connect_info":{"connect_url":"connect://localhost:32893","exe_path":null,"synchronous":true,"triple":null}],"identifier":4,"plugin_name":"mock","session_name":"Mock Accelerator Session"}],"auto_resume_native":false,"disable_bp":true}]#8e
intern-state     <   1> send packet: +
intern-state     history[1] tid=0x15d41f <   1> send packet: +
intern-state     <  19> send packet: $QStartNoAckMode#b0
intern-state     <   1> read packet: +
intern-state     <   6> read packet: $OK#9a
intern-state     <   1> send packet: +
intern-state     < 104> send packet: $qSupported:xmlRegisters=i386,arm,mips,arc;multiprocess+;fork-events+;vfork-events+;swbreak+;hwbreak+#cd
intern-state     < 159> read packet: $PacketSize=131072;QStartNoAckMode+;qEcho+;native-signals+;QThreadSuffixSupported+;QListThreadsInStopReply+;qXfer:features:read+;QNonStop+;jMultiBreakpoint+#f3
intern-state     <  26> send packet: $QThreadSuffixSupported#e4
intern-state     <   6> read packet: $OK#9a
intern-state     <  27> send packet: $QListThreadsInStopReply#21
intern-state     <   6> read packet: $OK#9a
intern-state     <  13> send packet: $qHostInfo#9b
intern-state     < 364> read packet: $triple:7838365f36342d2d6c696e75782d676e75;ptrsize:8;watchpoint_exceptions_received:after;endian:little;os_version:6.13.2;os_build:362e31332e322d305f66626b355f
68617264656e65645f7263325f305f67313733613962316463613431;os_kernel:233120534d5020576564204a756c2032332030393a32343a3330205044542032303235;hostname:6465766770753031312e656167322e66616365626f6f6b2e6
36f6d;#c4
intern-state     <  10> send packet: $vCont?llvm#49
intern-state     <  19> read packet: $vCont;c;C;s;S;t#11
intern-state     <  27> send packet: $qVAttachOrWaitSupported#38
intern-state     <   6> read packet: $OK#9a
intern-state     <  23> send packet: $QEnableErrorStrings#8c
intern-state     <   6> read packet: $OK#9a
intern-state     <  16> send packet: $qProcessInfo#dc
intern-state     <   7> read packet: $E01#a6
intern-state     <   6> send packet: $qC#b4
intern-state     <   7> read packet: $QC1#c5
intern-state     <   5> send packet: $?#3f
intern-state     < 291> read packet: $T00thread:1;name:Mock Accelerator Thread;threads:1;thread-pcs:0000000000001004;00:0010000000000000;01:0110000000000000;02:0210000000000000;03:0310000000000000
;04:0410000000000000;05:0510000000000000;reason:trace;description:6d6f636b20616363656c657261746f72207468726561642073746f70706564;llvm#83
intern-state     <  16> send packet: $qProcessInfo#dc
intern-state     <   7> read packet: $E01#a6
intern-state     <  16> send packet: $qProcessInfo#dc
intern-state     <   7> read packet: $E01#a6
intern-state     <  43> send packet: $qXfer:features:read:target.xml:0,131071#78
intern-state     < 889> read packet: $l<?xml version="1.0"?>
<target version="1.0">
  <architecture>x86_64</architecture>
  <feature>
    <reg name="r0" bitsize="64" regnum="0" offset="0" encoding="uint" format="hex" group="General Purpose Registers" />
    <reg name="r1" bitsize="64" regnum="1" offset="8" encoding="uint" format="hex" group="General Purpose Registers" />
    <reg name="sp" bitsize="64" regnum="2" offset="16" encoding="uint" format="hex" group="General Purpose Registers" generic="sp" />
    <reg name="fp" bitsize="64" regnum="3" offset="24" encoding="uint" format="hex" group="General Purpose Registers" generic="fp" />
    <reg name="pc" bitsize="64" regnum="4" offset="32" encoding="uint" format="hex" group="General Purpose Registers" generic="pc" />
    <reg name="flags" bitsize="64" regnum="5" offset="40" encoding="uint" format="hex" group="General Purpose Registers" />
  </feature>
</target>
llvm#82
intern-state     <  19> send packet: $p0;thread:0001;llvm#89
intern-state     <  20> read packet: $0010000000000000#01
intern-state     <  16> send packet: $qProcessInfo#dc
intern-state     <   7> read packet: $E01#a6
intern-state     <  19> send packet: $p0;thread:0001;llvm#89
intern-state     <  20> read packet: $0010000000000000#01
intern-state     <  16> send packet: $qProcessInfo#dc
intern-state     <   7> read packet: $E01#a6
intern-state     <  16> send packet: $qProcessInfo#dc
intern-state     <   7> read packet: $E01#a6
intern-state     <  16> send packet: $qProcessInfo#dc
intern-state     <   7> read packet: $E01#a6
intern-state     <  26> send packet: $qStructuredDataPlugins#02
intern-state     <   6> read packet: $[]#b8
intern-state     <  26> send packet: $qMemoryRegionInfo:1004#d9
intern-state     <  41> read packet: $error:6e6f7420696d706c656d656e746564;#f7
intern-state     <  16> send packet: $jThreadsInfo#c1
intern-state     < 198> read packet: $[{"description":"mock accelerator thread stopped","name":"Mock Accelerator Thread","reason":"trace","registers":{"2":"0210000000000000","3":"0310000000000000"
,"4":"0410000000000000"}],"tid":1}]]#4a

```
cenewcombe pushed a commit that referenced this pull request Jul 9, 2026
…long encodings (llvm#205907)

When a (signed or unsigned) LEB128 value is encoded with extra trailing
bytes that only carry zero- or sign-extension, the decode loop could
keep
running with the shift amount at 64 or beyond and then evaluate
`Slice << Shift`, which is undefined behavior for a 64-bit type.

The DWARF expression parser feeds attacker-controlled LEB128 operands
(such as `DW_OP_bregN` / `DW_OP_constu`) through
`DataExtractor::getULEB128` / `getSLEB128`, so the
`lldb-dwarf-expression-fuzzer` reaches this under UBSan.  The unsigned
case:

```
LEB128.h:152:20: runtime error: shift exponent 70 is too large for
64-bit type 'uint64_t' (aka 'unsigned long long')
    #0 llvm::decodeULEB128(...) LEB128.h:152
    #1 getLEB128<unsigned long long>(...) DataExtractor.cpp:227
    #2 llvm::DataExtractor::getULEB128(...) DataExtractor.cpp:241
    llvm#3 llvm::DWARFExpression::Operation::extract(...) DWARFExpression.cpp:218
    llvm#7 lldb_private::DWARFExpression::Evaluate(...) DWARFExpression.cpp:1333
    llvm#9 LLVMFuzzerTestOneInput lldb-dwarf-expression-fuzzer.cpp:83
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior LEB128.h:152:20
```

and the signed case, reached the same way:

```
LEB128.h:190:20: runtime error: shift exponent 70 is too large for
64-bit type 'uint64_t' (aka 'unsigned long long')
    #0 llvm::decodeSLEB128(...) LEB128.h:190
    #1 getLEB128<long long>(...) DataExtractor.cpp:227
    #2 llvm::DataExtractor::getSLEB128(...) DataExtractor.cpp:245
    llvm#3 llvm::DWARFExpression::Operation::extract(...) DWARFExpression.cpp:216
    llvm#7 lldb_private::DWARFExpression::Evaluate(...) DWARFExpression.cpp:1333
```

The existing range checks already guarantee that once `Shift` reaches 64
the remaining bytes are pure extension and contribute nothing to the
result, so skip the accumulating shift in that case.  Decoded values are
unchanged for all well-formed inputs.

Adds overlong-encoding regression cases to `LEB128Test`. Without the fix
the signed case is the UBSan diagnostic above in a sanitizer build, and
in a normal build the unsigned case also decodes to the wrong value (the
overlong `1` decodes as `11`).
cenewcombe pushed a commit that referenced this pull request Jul 9, 2026
The general rule is if si_addr is the same as the PC, we don't show it
because it doesn't add any new information.

SIGBUS signals are caused by an instruction trying to do something, but
si_addr is not the address of the instruction. It's some virtual
address, which is the important bit so add it to the description.

https://man7.org/linux/man-pages/man7/signal.7.html
> SIGBUS <...> Bus error (bad memory access)

Before:
```
* thread #1, name = 'test.o', stop reason = signal SIGBUS: illegal address
  * frame #0: 0x0000aaaaaaaa0b80 test.o`main at test.c:42:13
```
After:
```
* thread #1, name = 'test.o', stop reason = signal SIGBUS: illegal address (fault address=0xfffff7ff6000)
  * frame #0: 0x0000aaaaaaaa0b80 test.o`main at test.c:42:13
```
I am not adding test cases for this because:
* They would be architecture specific.
* Reliably generating BUS_OBJERR seems difficult.
* Signal reporting has good coverage as it is, so we know that
si_code/si_addr are handled correctly.
cenewcombe pushed a commit that referenced this pull request Jul 22, 2026
…lvm#211103)

`cuf-alloc-delay` sinks a managed descriptor's `cuf.alloc` group
(`{cuf.alloc, fir.store, fir.declare}`) to just before its first use, to
defer the managed allocation. It special-cased the store of the descriptor
into a host-association tuple slot (`fir.store` to a `fir.llvm_ptr`): it did
not count that store (nor the call that consumes the tuple) as a use, and moved
the store along with the group. As a result, when a managed allocatable descriptor
is stored into a host-association tuple and passed to an internal procedure, the group
could be sunk **past** the internal-procedure call that reads the tuple, so the
callee observed an uninitialized descriptor. On more complex tuples, moving the
host-association store also broke SSA dominance, producing
`operand #1 does not dominate this use`.

With this PR, `findDelayTarget` now treats **every** use of the
descriptor as a real use, including the host-association store. The group is only ever sunk to
*before* the first use, and the host-association store is never moved (it reads
its own `fir.coordinate_of` slot). This keeps the descriptor initialized before
the tuple is consumed and is dominance-safe by construction.
cenewcombe pushed a commit that referenced this pull request Aug 6, 2026
…lvm#212759)

I see the following 

```
 anutosh491@Anutoshs-MacBook-Air llvm-project % cat /private/tmp/wasm-scalable-shift-cost.ll
define <vscale x 4 x i32> @shift(<vscale x 4 x i32> %x,
                                 <vscale x 4 x i32> %amount) {
  %result = shl <vscale x 4 x i32> %x, %amount
  ret <vscale x 4 x i32> %result
}


 anutosh491@Anutoshs-MacBook-Air llvm-project % build-assert/bin/opt \
  -mtriple=wasm32-unknown-unknown \
  -mattr=+simd128 \
  -passes='print<cost-model>' \
  -disable-output \
  /private/tmp/wasm-scalable-shift-cost.ll
Printing analysis 'Cost Model Analysis' for function 'shift':
Cost Model: Assertion failed: (isa<To>(Val) && "cast<Ty>() argument of incompatible type!"), function cast, file Casting.h, line 572.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace and instructions to reproduce the bug.
Stack dump:
0.      Program arguments: build-assert/bin/opt -mtriple=wasm32-unknown-unknown -mattr=+simd128 -passes=print<cost-model> -disable-output /private/tmp/wasm-scalable-shift-cost.ll
1.      Running pass "function(print<cost-model>)" on module "/private/tmp/wasm-scalable-shift-cost.ll"
2.      Running pass "print<cost-model>" on function "shift"
 #0 0x0000000105b7a56c llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/Users/anutosh491/work/llvm-project/build-assert/bin/opt+0x102f6256c)
 #1 0x0000000105b78248 llvm::sys::RunSignalHandlers() (/Users/anutosh491/work/llvm-project/build-assert/bin/opt+0x102f60248)
 #2 0x0000000105b7b170 SignalHandler(int, __siginfo*, void*) (/Users/anutosh491/work/llvm-project/build-assert/bin/opt+0x102f63170)
 llvm#3 0x000000018b5f7744 (/usr/lib/system/libsystem_platform.dylib+0x1804fb744)
 llvm#4 0x000000018b5ed8d8 (/usr/lib/system/libsystem_pthread.dylib+0x1804f18d8)
 llvm#5 0x000000018b4f4644 (/usr/lib/system/libsystem_c.dylib+0x1803f8644)
 llvm#6 0x000000018b4f38a0 (/usr/lib/system/libsystem_c.dylib+0x1803f78a0)
 llvm#7 0x0000000104036ddc llvm::BasicTTIImplBase<llvm::WebAssemblyTTIImpl>::getArithmeticInstrCost(unsigned int, llvm::Type*, llvm::TargetTransformInfo::TargetCostKind, llvm::TargetTransformInfo::OperandValueInfo, llvm::TargetTransformInfo::OperandValueInfo, llvm::ArrayRef<llvm::Value const*>, llvm::Instruction const*) const (/Users/anutosh491/work/llvm-project/build-assert/bin/opt+0x10141eddc)
 llvm#8 0x000000010403b0ac llvm::TargetTransformInfoImplCRTPBase<llvm::WebAssemblyTTIImpl>::getInstructionCost(llvm::User const*, llvm::ArrayRef<llvm::Value const*>, llvm::TargetTransformInfo::TargetCostKind) const (/Users/anutosh491/work/llvm-project/build-assert/bin/opt+0x1014230ac)
 llvm#9 0x00000001049162c8 llvm::TargetTransformInfo::getInstructionCost(llvm::User const*, llvm::ArrayRef<llvm::Value const*>, llvm::TargetTransformInfo::TargetCostKind) const (/Users/anutosh491/work/llvm-project/build-assert/bin/opt+0x101cfe2c8)
llvm#10 0x00000001058d90b4 llvm::TargetTransformInfo::getInstructionCost(llvm::User const*, llvm::TargetTransformInfo::TargetCostKind) const (/Users/anutosh491/work/llvm-project/build-assert/bin/opt+0x102cc10b4)
llvm#11 0x000000010468a368 getCost(llvm::Instruction&, llvm::TargetTransformInfo::TargetCostKind, llvm::TargetTransformInfo&) (/Users/anutosh491/work/llvm-project/build-assert/bin/opt+0x101a72368)
llvm#12 0x0000000104689dd4 llvm::CostModelPrinterPass::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/Users/anutosh491/work/llvm-project/build-assert/bin/opt+0x101a71dd4)
llvm#13 0x0000000105186554 llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/Users/anutosh491/work/llvm-project/build-assert/bin/opt+0x10256e554)
llvm#14 0x000000010518a680 llvm::ModuleToFunctionPassAdaptor::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/Users/anutosh491/work/llvm-project/build-assert/bin/opt+0x102572680)
llvm#15 0x0000000105185418 llvm::PassManager<llvm::Module, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/Users/anutosh491/work/llvm-project/build-assert/bin/opt+0x10256d418)
llvm#16 0x0000000106127cb0 llvm::runPassPipeline(llvm::StringRef, llvm::Module&, llvm::TargetMachine*, llvm::TargetLibraryInfoImpl*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::StringRef, llvm::ArrayRef<llvm::PassPlugin>, llvm::ArrayRef<std::__1::function<void (llvm::PassBuilder&)>>, llvm::opt_tool::OutputKind, llvm::opt_tool::VerifierKind, bool, bool, bool, bool, bool, bool, bool, bool) (/Users/anutosh491/work/llvm-project/build-assert/bin/opt+0x10350fcb0)
llvm#17 0x0000000106131eac optMain (/Users/anutosh491/work/llvm-project/build-assert/bin/opt+0x103519eac)
llvm#18 0x000000018b22fe00
zsh: abort      build-assert/bin/opt -mtriple=wasm32-unknown-unknown -mattr=+simd128 
```
cenewcombe pushed a commit that referenced this pull request Aug 6, 2026
```
define <8 x half> @insert_v8f16(<8 x half> %v, half %x) {
  %r = insertelement <8 x half> %v, half %x, i32 3
  ret <8 x half> %r
}
```

```
llc \
  -mtriple=wasm32-unknown-unknown \
  -mattr=+simd128,+fp16 \
  -o /dev/null \
  /private/tmp/wasm-v8f16-insert-only.ll
```

Would lead to 
```
Initial selection DAG: %bb.0 'insert_v8f16:'
SelectionDAG has 10 nodes:
    t0: ch,glue = EntryToken
      t2: v8f16 = WebAssemblyISD::ARGUMENT TargetConstant:i32<0>
          t4: i32 = WebAssemblyISD::ARGUMENT TargetConstant:i32<1>
        t5: i16 = truncate t4
      t6: f16 = bitcast t5
    t8: v8f16 = insert_vector_elt t2, t6, Constant:i32<3>
  t9: ch = WebAssemblyISD::RETURN t0, t8

Soft promote half operand 1:
t8: v8f16 = insert_vector_elt t2, t6, Constant:i32<3>

SoftPromoteHalfOperand Op #1:
t8: v8f16 = insert_vector_elt t2, t6, Constant:i32<3>

LLVM ERROR: Do not know how to soft promote this operator's operand!
```
cenewcombe pushed a commit that referenced this pull request Aug 14, 2026
…ical blocks (llvm#215036)

Merging identical blocks threads their differing values through the
predecessors' terminators as new successor operands, but the only
legality question asked of a predecessor was whether its terminator
implements `BranchOpInterface` (`ableToUpdatePredOperands`). The
transform's implicit assumption is that such a terminator can forward
operands of **any** type — false for dialects whose branch ops constrain
successor operand types. The LLVM dialect terminators declare theirs as
`Variadic<LLVM_Type>`, so merging two blocks that differ in, say, an
index-typed operand rewrote a verifying `llvm.cond_br` into one that no
longer verifies.

Reproducer (mixed-dialect IR of the kind a progressive lowering/raising
pipeline carries), via `mlir-opt
-pass-pipeline='builtin.module(func.func(canonicalize{region-simplify=aggressive}))'`:

```mlir
func.func @f(%m: memref<4xf32>, %c: i1) {
  %f = arith.constant 1.0 : f32
  %i0 = arith.constant 0 : index
  %i1 = arith.constant 1 : index
  llvm.cond_br %c, ^a, ^b
^a:
  memref.store %f, %m[%i0] : memref<4xf32>
  llvm.return
^b:
  memref.store %f, %m[%i1] : memref<4xf32>
  llvm.return
}
```

previously produced

```
error: 'llvm.cond_br' op operand #1 must be variadic of LLVM dialect-compatible type, but got 'index'
note: see current operation: "llvm.cond_br"(%arg1, %1, %2)[^bb1, ^bb1] ...
```

i.e. the transform manufactured IR that cannot verify. (Any greedy
driver running at `GreedySimplifyRegionLevel::Aggressive` — the
`applyPatternsGreedily` default — hits this; downstream we currently
work around it by dropping to `Normal`.)

This adds `mayForwardTypeToSuccessor(unsigned index, Type type)` to
`BranchOpInterface`, default permissive, and makes block merging refuse
a cluster when any predecessor terminator refuses any of the would-be
block argument types. The LLVM dialect terminators (`br`, `cond_br`,
`switch`, `invoke`, `indirectbr`) override it with `isCompatibleType`.
The new test pins both directions: the index-typed merge is refused, an
i32-typed merge through `llvm.cond_br` still happens.

Assisted-by: Claude
cenewcombe pushed a commit that referenced this pull request Aug 14, 2026
…ction of a mask (llvm#215187)

foldPartialReduceAdd synthesises the reduction's multiplier at the
operand's type. At i1 a splat of 1 is all ones, which sign extends to
-1, so the signed forms compute (-1) x (-1) = +1 per lane and sum to +n
where sum(sext(mask)) must be -n.

```llvm
%cmp  = icmp eq <16 x i8> %a, %b
%sext = sext <16 x i1> %cmp to <16 x i32>
%r    = call <4 x i32> @llvm.vector.partial.reduce.add(<4 x i32> %acc, <16 x i32> %sext)
```

-mattr=+neon sums to -n:

```
cmeq    v1.16b, v1.16b, v2.16b
sshll   v2.8h, v1.8b, #0
sshll2  v1.8h, v1.16b, #0
saddw   v0.4s, v0.4s, v2.4h
saddw2  v0.4s, v0.4s, v2.8h
saddw   v0.4s, v0.4s, v1.4h
saddw2  v0.4s, v0.4s, v1.8h
```

-mattr=+neon,+dotprod sums to +n:

```
movi    v3.2d, #0xffffffffffffffff
cmeq    v1.16b, v1.16b, v2.16b
sdot    v0.4s, v1.16b, v3.16b
```

This patch extends i1 masks to the promoted type before the multiplier
is built. That gives `movi v3.16b, #1` and the dot product path agrees
with the expansion.

Part of llvm#204897.
cenewcombe pushed a commit that referenced this pull request Aug 19, 2026
I see the following 

```
 anutosh491@Anutoshs-MacBook-Air llvm-project % cat /private/tmp/wasm-f16-select.ll
define <8 x half> @select_v8f16(i1 %cond, <8 x half> %a, <8 x half> %b) {
  %result = select i1 %cond, <8 x half> %a, <8 x half> %b
  ret <8 x half> %result
}
```
```

 anutosh491@Anutoshs-MacBook-Air llvm-project % build-assert/bin/llc \             
  -mtriple=wasm32-unknown-unknown \
  -mattr=+simd128,+fp16 \
  -o /dev/null \
  /private/tmp/wasm-f16-select.ll
LLVM ERROR: Cannot select: t8: v8f16 = select t12, t4, t6
  t12: i32 = and t2, Constant:i32<1>
    t2: i32 = WebAssemblyISD::ARGUMENT TargetConstant:i32<0>
  t4: v8f16 = WebAssemblyISD::ARGUMENT TargetConstant:i32<1>
  t6: v8f16 = WebAssemblyISD::ARGUMENT TargetConstant:i32<2>
In function: select_v8f16
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace and instructions to reproduce the bug.
Stack dump:
0. Program arguments: build-assert/bin/llc -mtriple=wasm32-unknown-unknown -mattr=+simd128,+fp16 -o /dev/null /private/tmp/wasm-f16-select.ll
1. Running pass 'Function Pass Manager' on module '/private/tmp/wasm-f16-select.ll'.
2. Running pass 'WebAssembly Instruction Selection' on function '@select_v8f16'
   #0 0x0000000103c6852c llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/Users/anutosh491/work/llvm-project/build-assert/bin/llc+0x1030e852c)
   #1 0x0000000103c66208 llvm::sys::RunSignalHandlers() (/Users/anutosh491/work/llvm-project/build-assert/bin/llc+0x1030e6208)
   #2 0x0000000103c69130 SignalHandler(int, __siginfo*, void*) (/Users/anutosh491/work/llvm-project/build-assert/bin/llc+0x1030e9130)
   llvm#3 0x000000018b5f7744 (/usr/lib/system/libsystem_platform.dylib+0x1804fb744)
   llvm#4 0x000000018b5ed8d8 (/usr/lib/system/libsystem_pthread.dylib+0x1804f18d8)
   llvm#5 0x000000018b4f4644 (/usr/lib/system/libsystem_c.dylib+0x1803f8644)
   llvm#6 0x0000000103bbc0b4 llvm::report_fatal_error(llvm::Twine const&, bool) (/Users/anutosh491/work/llvm-project/build-assert/bin/llc+0x10303c0b4)
   llvm#7 0x0000000103af91b8 llvm::SelectionDAGISel::CannotYetSelect(llvm::SDNode*) (/Users/anutosh491/work/llvm-project/build-assert/bin/llc+0x102f791b8)
   llvm#8 0x0000000103af813c llvm::SelectionDAGISel::SelectCodeCommon(llvm::SDNode*, unsigned char const*, unsigned int, unsigned char const*) (/Users/anutosh491/work/llvm-project/build-assert/bin/llc+0x102f7813c)
   llvm#9 0x0000000101f66b78 (anonymous namespace)::WebAssemblyDAGToDAGISel::Select(llvm::SDNode*) (/Users/anutosh491/work/llvm-project/build-assert/bin/llc+0x1013e6b78)
llvm#10 0x0000000103aee46c llvm::SelectionDAGISel::DoInstructionSelection() (/Users/anutosh491/work/llvm-project/build-assert/bin/llc+0x102f6e46c)
llvm#11 0x0000000103aed400 llvm::SelectionDAGISel::CodeGenAndEmitDAG() (/Users/anutosh491/work/llvm-project/build-assert/bin/llc+0x102f6d400)
llvm#12 0x0000000103aeb4b4 llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) (/Users/anutosh491/work/llvm-project/build-assert/bin/llc+0x102f6b4b4)
llvm#13 0x0000000103ae8ba8 llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) (/Users/anutosh491/work/llvm-project/build-assert/bin/llc+0x102f68ba8)
llvm#14 0x0000000103ae6cd8 llvm::SelectionDAGISelLegacy::runOnMachineFunction(llvm::MachineFunction&) (/Users/anutosh491/work/llvm-project/build-assert/bin/llc+0x102f66cd8)
llvm#15 0x0000000102b71d28 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (/Users/anutosh491/work/llvm-project/build-assert/bin/llc+0x101ff1d28)
llvm#16 0x0000000103096900 llvm::FPPassManager::runOnFunction(llvm::Function&) (/Users/anutosh491/work/llvm-project/build-assert/bin/llc+0x102516900)
llvm#17 0x000000010309cc00 llvm::FPPassManager::runOnModule(llvm::Module&) (/Users/anutosh491/work/llvm-project/build-assert/bin/llc+0x10251cc00)
llvm#18 0x0000000103097174 llvm::legacy::PassManagerImpl::run(llvm::Module&) (/Users/anutosh491/work/llvm-project/build-assert/bin/llc+0x102517174)
llvm#19 0x0000000100b880a4 main (/Users/anutosh491/work/llvm-project/build-assert/bin/llc+0x1000080a4)
llvm#20 0x000000018b22fe00
zsh: abort      build-assert/bin/llc -mtriple=wasm32-unknown-unknown -mattr=+simd128,+fp16 -o

```
cenewcombe pushed a commit that referenced this pull request Aug 19, 2026
…list (llvm#216847)

`Thread::ClearStackFrames` keeps the previous public frame list as the
predecessor of the next unwinder list. When a scripted frame provider is
registered, that public list is a `SyntheticStackFrameList` holding
`BorrowedStackFrames`, and the unwinder list's merge step reuses a
predecessor frame whenever the stack IDs match, so it adopted frames
belonging to the provider's list.

`UpdatePreviousFrameFromCurrentFrame` refreshes
`StackFrame::m_frame_index`, but `BorrowedStackFrame::GetFrameIndex()`
returns its own `m_new_frame_index`, which supersedes it. The adopted
frame keeps reporting its index from the previous stop, so once the
stack grows the backtrace stops counting up:

```
  frame #1: middle
  frame #1: main
  frame #2: start
```

Such a frame also delegates its stack ID, register context and symbol
context to a frame from the previous stop that the merge never
refreshes, so it could report stale state as well. In the backtrace
above, main also lost its source location.

When the merge finds a matching predecessor frame that is a
`BorrowedStackFrame`, keep the freshly unwound frame instead of adopting
it. Only providers create BorrowedStackFrames, so this never drops a
frame the unwinder built itself.

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
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3 participants