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[DRAFT] Loop exploration function pass #7

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@cjappl cjappl commented Sep 4, 2024

Attempt to detect unbound loops in our function pass

cjappl
cjappl commented Sep 4, 2024
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clang/lib/CodeGen/BackendUtil.cpp Outdated
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Here is where we add the SROA pass

cjappl
cjappl commented Sep 4, 2024
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llvm/include/llvm/Transforms/Scalar/SROA.h Outdated
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SROA does not ever run, unless I add this hack here

@cjappl cjappl force-pushed the loop_exploration_function_pass branch from e4d2102 to b0c405c Compare September 6, 2024 18:55
cjappl pushed a commit that referenced this pull request Sep 9, 2024
@vabridgers
[analyzer] Remove overzealous "No dispatcher registered" assertion (l…
da11ede 
…lvm#107294)

Random testing revealed it's possible to crash the analyzer with the
command line invocation:

clang -cc1 -analyze -analyzer-checker=nullability empty.c

where the source file, empty.c is an empty source file.

```
clang: <root>/clang/lib/StaticAnalyzer/Core/CheckerManager.cpp:56:
   void clang::ento::CheckerManager::finishedCheckerRegistration():
     Assertion `Event.second.HasDispatcher && "No dispatcher registered for an event"' failed.

PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/

Stack dump:
0.      Program arguments: clang -cc1 -analyze -analyzer-checker=nullability nullability-nocrash.c
 #0 ...
 ...
 #7 <addr> clang::ento::CheckerManager::finishedCheckerRegistration()
 #8 <addr> clang::ento::CheckerManager::CheckerManager(clang::ASTContext&,
             clang::AnalyzerOptions&, clang::Preprocessor const&,
             llvm::ArrayRef<std::__cxx11::basic_string<char, std::char_traits<char>,
             std::allocator<char>>>, llvm::ArrayRef<std::function<void (clang::ento::CheckerRegistry&)>>)
```

This commit removes the assertion which failed here, because it was
logically incorrect: it required that if an Event is handled by some
(enabled) checker, then there must be an **enabled** checker which can
emit that kind of Event. It should be OK to disable the event-producing
checkers but enable an event-consuming checker which has different
responsibilities in addition to handling the events.
 
Note that this assertion was in an `#ifndef NDEBUG` block, so this
change does not impact the non-debug builds.

Co-authored-by: Vince Bridgers <[email protected]>
@cjappl cjappl force-pushed the loop_exploration_function_pass branch from b0c405c to 428d2ec Compare September 9, 2024 21:21
cjappl pushed a commit that referenced this pull request Sep 18, 2024
@rorth
[ASan] Disable InstallAtForkHandler on Linux/sparc64 (llvm#108542)
9b237b4 
When SPARC Asan testing is enabled by PR llvm#107405, many Linux/sparc64
tests just hang like
```
#0  0xf7ae8e90 in syscall () from /usr/lib32/libc.so.6
#1  0x701065e8 in __sanitizer::FutexWait(__sanitizer::atomic_uint32_t*, unsigned int) ()
    at compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp:766
#2  0x70107c90 in Wait ()
    at compiler-rt/lib/sanitizer_common/sanitizer_mutex.cpp:35
#3  0x700f7cac in Lock ()
    at compiler-rt/lib/asan/../sanitizer_common/sanitizer_mutex.h:196
#4  Lock ()
    at compiler-rt/lib/asan/../sanitizer_common/sanitizer_thread_registry.h:98
#5  LockThreads ()
    at compiler-rt/lib/asan/asan_thread.cpp:489
#6  0x700e9c8c in __asan::BeforeFork() ()
    at compiler-rt/lib/asan/asan_posix.cpp:157
#7  0xf7ac83f4 in ?? () from /usr/lib32/libc.so.6
Backtrace stopped: previous frame identical to this frame (corrupt stack?)
```
It turns out that this happens in tests using `internal_fork` (e.g.
invoking `llvm-symbolizer`): unlike most other Linux targets, which use
`clone`, Linux/sparc64 has to use `__fork` instead. While `clone`
doesn't trigger `pthread_atfork` handlers, `__fork` obviously does,
causing the hang.

To avoid this, this patch disables `InstallAtForkHandler` and lets the
ASan tests run to completion.

Tested on `sparc64-unknown-linux-gnu`.
cjappl pushed a commit that referenced this pull request Nov 19, 2024
@chandraghale
Fix for codegen Crash in Clang when using locator omp_all_memory with…
44a6b3a 
… depobj construct (llvm#114221)

A codegen crash is occurring when a depend object was initialized with
omp_all_memory in the depobj directive.
llvm#114214
The root cause of issue looks to be the improper handling of the
dependency list when omp_all_memory was specified.

The change introduces the use of OMPTaskDataTy to manage dependencies.
The buildDependences function is called to construct the dependency
list, and the list is iterated over to emit and store the dependencies.

Reduced Test Case : 
```
#include <omp.h>

int main()

{ omp_depend_t obj; #pragma omp depobj(obj) depend(inout: omp_all_memory) }
```

```
 #1 0x0000000003de6623 SignalHandler(int) Signals.cpp:0:0
 #2 0x00007f8e4a6b990f (/lib64/libpthread.so.0+0x1690f)
 #3 0x00007f8e4a117d2a raise (/lib64/libc.so.6+0x4ad2a)
 #4 0x00007f8e4a1193e4 abort (/lib64/libc.so.6+0x4c3e4)
 #5 0x00007f8e4a10fc69 __assert_fail_base (/lib64/libc.so.6+0x42c69)
 #6 0x00007f8e4a10fcf1 __assert_fail (/lib64/libc.so.6+0x42cf1)
 #7 0x0000000004114367 clang::CodeGen::CodeGenFunction::EmitOMPDepobjDirective(clang::OMPDepobjDirective const&) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x4114367)
 #8 0x00000000040f8fac clang::CodeGen::CodeGenFunction::EmitStmt(clang::Stmt const*, llvm::ArrayRef<clang::Attr const*>) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x40f8fac)
 #9 0x00000000040ff4fb clang::CodeGen::CodeGenFunction::EmitCompoundStmtWithoutScope(clang::CompoundStmt const&, bool, clang::CodeGen::AggValueSlot) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x40ff4fb)
#10 0x00000000041847b2 clang::CodeGen::CodeGenFunction::EmitFunctionBody(clang::Stmt const*) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x41847b2)
#11 0x0000000004199e4a clang::CodeGen::CodeGenFunction::GenerateCode(clang::GlobalDecl, llvm::Function*, clang::CodeGen::CGFunctionInfo const&) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x4199e4a)
#12 0x00000000041f7b9d clang::CodeGen::CodeGenModule::EmitGlobalFunctionDefinition(clang::GlobalDecl, llvm::GlobalValue*) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x41f7b9d)
#13 0x00000000041f16a3 clang::CodeGen::CodeGenModule::EmitGlobalDefinition(clang::GlobalDecl, llvm::GlobalValue*) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x41f16a3)
#14 0x00000000041fd954 clang::CodeGen::CodeGenModule::EmitDeferred() (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x41fd954)
realtime-sanitizer#15 0x0000000004200277 clang::CodeGen::CodeGenModule::Release() (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x4200277)
realtime-sanitizer#16 0x00000000046b6a49 (anonymous namespace)::CodeGeneratorImpl::HandleTranslationUnit(clang::ASTContext&) ModuleBuilder.cpp:0:0
realtime-sanitizer#17 0x00000000046b4cb6 clang::BackendConsumer::HandleTranslationUnit(clang::ASTContext&) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x46b4cb6)
realtime-sanitizer#18 0x0000000006204d5c clang::ParseAST(clang::Sema&, bool, bool) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x6204d5c)
realtime-sanitizer#19 0x000000000496b278 clang::FrontendAction::Execute() (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x496b278)
realtime-sanitizer#20 0x00000000048dd074 clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x48dd074)
realtime-sanitizer#21 0x0000000004a38092 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x4a38092)
realtime-sanitizer#22 0x0000000000fd4e9c cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0xfd4e9c)
realtime-sanitizer#23 0x0000000000fcca73 ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&) driver.cpp:0:0
realtime-sanitizer#24 0x0000000000fd140c clang_main(int, char**, llvm::ToolContext const&) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0xfd140c)
realtime-sanitizer#25 0x0000000000ee2ef3 main (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0xee2ef3)
realtime-sanitizer#26 0x00007f8e4a10224c __libc_start_main (/lib64/libc.so.6+0x3524c)
realtime-sanitizer#27 0x0000000000fcaae9 _start /home/abuild/rpmbuild/BUILD/glibc-2.31/csu/../sysdeps/x86_64/start.S:120:0
clang: error: unable to execute command: Aborted
```

---------

Co-authored-by: Chandra Ghale <[email protected]>
cjappl pushed a commit that referenced this pull request Nov 20, 2024
@Tazdevil971
[MIPS] Updated MIPS N calling conventions so that fp16 arguments no l…
8cd348c 
…onger cause a crash (llvm#116569)

This PR fixes a bug introduced by llvm#110199, which causes any half float
argument to crash the compiler on MIPS64.

Currently compiling this bit of code with `llc -mtriple=mips64`: 
```
define void @half_args(half %a) nounwind {
entry:
        ret void
}
```

Crashes with the following log:
```
LLVM ERROR: unable to allocate function argument #0
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.	Program arguments: llc -mtriple=mips64
1.	Running pass 'Function Pass Manager' on module '<stdin>'.
2.	Running pass 'MIPS DAG->DAG Pattern Instruction Selection' on function '@half_args'
 #0 0x000055a3a4013df8 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x32d0df8)
 #1 0x000055a3a401199e llvm::sys::RunSignalHandlers() (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x32ce99e)
 #2 0x000055a3a40144a8 SignalHandler(int) Signals.cpp:0:0
 #3 0x00007f00bde558c0 __restore_rt libc_sigaction.c:0:0
 #4 0x00007f00bdea462c __pthread_kill_implementation ./nptl/pthread_kill.c:44:76
 #5 0x00007f00bde55822 gsignal ./signal/../sysdeps/posix/raise.c:27:6
 #6 0x00007f00bde3e4af abort ./stdlib/abort.c:81:7
 #7 0x000055a3a3f80e3c llvm::report_fatal_error(llvm::Twine const&, bool) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x323de3c)
 #8 0x000055a3a2e20dfa (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x20dddfa)
 #9 0x000055a3a2a34e20 llvm::MipsTargetLowering::LowerFormalArguments(llvm::SDValue, unsigned int, bool, llvm::SmallVectorImpl<llvm::ISD::InputArg> const&, llvm::SDLoc const&, llvm::SelectionDAG&, llvm::SmallVectorImpl<llvm::SDValue>&) const MipsISelLowering.cpp:0:0
#10 0x000055a3a3d896a9 llvm::SelectionDAGISel::LowerArguments(llvm::Function const&) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x30466a9)
#11 0x000055a3a3e0b3ec llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x30c83ec)
#12 0x000055a3a3e09e21 llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x30c6e21)
#13 0x000055a3a2aae1ca llvm::MipsDAGToDAGISel::runOnMachineFunction(llvm::MachineFunction&) MipsISelDAGToDAG.cpp:0:0
#14 0x000055a3a3e07706 llvm::SelectionDAGISelLegacy::runOnMachineFunction(llvm::MachineFunction&) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x30c4706)
realtime-sanitizer#15 0x000055a3a3051ed6 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x230eed6)
realtime-sanitizer#16 0x000055a3a35a3ec9 llvm::FPPassManager::runOnFunction(llvm::Function&) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x2860ec9)
realtime-sanitizer#17 0x000055a3a35ac3b2 llvm::FPPassManager::runOnModule(llvm::Module&) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x28693b2)
realtime-sanitizer#18 0x000055a3a35a499c llvm::legacy::PassManagerImpl::run(llvm::Module&) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x286199c)
realtime-sanitizer#19 0x000055a3a262abbb main (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x18e7bbb)
realtime-sanitizer#20 0x00007f00bde3fc4c __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:74:3
realtime-sanitizer#21 0x00007f00bde3fd05 call_init ./csu/../csu/libc-start.c:128:20
realtime-sanitizer#22 0x00007f00bde3fd05 __libc_start_main@GLIBC_2.2.5 ./csu/../csu/libc-start.c:347:5
realtime-sanitizer#23 0x000055a3a2624921 _start /builddir/glibc-2.39/csu/../sysdeps/x86_64/start.S:117:0
```

This is caused by the fact that after the change, `f16`s are no longer
lowered as `f32`s in calls.

Two possible fixes are available:
- Update calling conventions to properly support passing `f16` as
integers.
- Update `useFPRegsForHalfType()` to return `true` so that `f16` are
still kept in `f32` registers, as before llvm#110199.

This PR implements the first solution to not introduce any more ABI
changes as llvm#110199 already did.

As of what is the correct ABI for halfs, I don't think there is a
correct answer. GCC doesn't support halfs on MIPS, and I couldn't find
any information on old MIPS ABI manuals either.
cjappl pushed a commit that referenced this pull request Nov 29, 2024
@dty2
[flang]Add new intrinsic function backtrace and complete the TODO of …
159e601 
…abort (llvm#117603)

Hey guys, I found that Flang's built-in ABORT function is incomplete
when I was using it. Compared with gfortran's ABORT (which can both
abort and print out a backtrace), flang's ABORT implementation lacks the
function of printing out a backtrace. This feature is essential for
debugging and understanding the call stack at the failure point.

To solve this problem, I completed the "// TODO:" of the abort function,
and then implemented an additional built-in function BACKTRACE for
flang. After a brief reading of the relevant source code, I used
backtrace and backtrace_symbols in "execinfo.h" to quickly implement
this. But since I used the above two functions directly, my
implementation is slightly different from gfortran's implementation (in
the output, the function call stack before main is additionally output,
and the function line number is missing). In addition, since I used the
above two functions, I did not need to add -g to embed debug information
into the ELF file, but needed -rdynamic to ensure that the symbols are
added to the dynamic symbol table (so that the function name will be
printed out).

Here is a comparison of the output between gfortran 's backtrace and my
implementation:
gfortran's implemention output:
```
#0  0x557eb71f4184 in testfun2_
        at /home/hunter/plct/fortran/test.f90:5
#1  0x557eb71f4165 in testfun1_
        at /home/hunter/plct/fortran/test.f90:13
#2  0x557eb71f4192 in test_backtrace
        at /home/hunter/plct/fortran/test.f90:17
#3  0x557eb71f41ce in main
        at /home/hunter/plct/fortran/test.f90:18
```
my impelmention output:
```
Backtrace:
#0 ./test(_FortranABacktrace+0x32) [0x574f07efcf92]
#1 ./test(testfun2_+0x14) [0x574f07efc7b4]
#2 ./test(testfun1_+0xd) [0x574f07efc7cd]
#3 ./test(_QQmain+0x9) [0x574f07efc7e9]
#4 ./test(main+0x12) [0x574f07efc802]
#5 /usr/lib/libc.so.6(+0x25e08) [0x76954694fe08]
#6 /usr/lib/libc.so.6(__libc_start_main+0x8c) [0x76954694fecc]
#7 ./test(_start+0x25) [0x574f07efc6c5]
```
test program is:
```
function testfun2() result(err)
  implicit none
  integer :: err
  err = 1
  call backtrace
end function testfun2

subroutine testfun1()
  implicit none
  integer :: err
  integer :: testfun2

  err = testfun2()
end subroutine testfun1

program test_backtrace
  call testfun1()
end program test_backtrace
```
I am well aware of the importance of line numbers, so I am now working
on implementing line numbers (by parsing DWARF information) and
supporting cross-platform (Windows) support.
cjappl pushed a commit that referenced this pull request Dec 6, 2024
@jle-quel
[Driver][OpenMP] Fix OpenMP target-toolchain-option parser (llvm#115375)
952c515 
## Description

This PR fixes a segmentation fault that occurs when passing options
requiring arguments via `-Xopenmp-target=<triple>`. The issue was that
the function `Driver::getOffloadArchs` did not properly parse the
extracted option, but instead assumed it was valid, leading to a crash
when incomplete arguments were provided.

## Backtrace

```sh
llvm-project/build/bin/clang++ main.cpp -fopenmp=libomp -fopenmp-targets=powerpc64le-ibm-linux-gnu -Xopenmp-target=powerpc64le-ibm-linux-gnu -o 
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: llvm-project/build/bin/clang++ main.cpp -fopenmp=libomp -fopenmp-targets=powerpc64le-ibm-linux-gnu -Xopenmp-target=powerpc64le-ibm-linux-gnu -o
1.      Compilation construction
2.      Building compilation actions
 #0 0x0000562fb21c363b llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (llvm-project/build/bin/clang+++0x392f63b)
 #1 0x0000562fb21c0e3c SignalHandler(int) Signals.cpp:0:0
 #2 0x00007fcbf6c81420 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x14420)
 #3 0x0000562fb1fa5d70 llvm::opt::Option::matches(llvm::opt::OptSpecifier) const (llvm-project/build/bin/clang+++0x3711d70)
 #4 0x0000562fb2a78e7d clang::driver::Driver::getOffloadArchs(clang::driver::Compilation&, llvm::opt::DerivedArgList const&, clang::driver::Action::OffloadKind, clang::driver::ToolChain const*, bool) const (llvm-project/build/bin/clang+++0x41e4e7d)
 #5 0x0000562fb2a7a9aa clang::driver::Driver::BuildOffloadingActions(clang::driver::Compilation&, llvm::opt::DerivedArgList&, std::pair<clang::driver::types::ID, llvm::opt::Arg const*> const&, clang::driver::Action*) const (.part.1164) Driver.cpp:0:0
 #6 0x0000562fb2a7c093 clang::driver::Driver::BuildActions(clang::driver::Compilation&, llvm::opt::DerivedArgList&, llvm::SmallVector<std::pair<clang::driver::types::ID, llvm::opt::Arg const*>, 16u> const&, llvm::SmallVector<clang::driver::Action*, 3u>&) const (llvm-project/build/bin/clang+++0x41e8093)
 #7 0x0000562fb2a8395d clang::driver::Driver::BuildCompilation(llvm::ArrayRef<char const*>) (llvm-project/build/bin/clang+++0x41ef95d)
 #8 0x0000562faf92684c clang_main(int, char**, llvm::ToolContext const&) (llvm-project/build/bin/clang+++0x109284c)
 #9 0x0000562faf826cc6 main (llvm-project/build/bin/clang+++0xf92cc6)
#10 0x00007fcbf6699083 __libc_start_main /build/glibc-LcI20x/glibc-2.31/csu/../csu/libc-start.c:342:3
#11 0x0000562faf923a5e _start (llvm-project/build/bin/clang+++0x108fa5e)
[1]    2628042 segmentation fault (core dumped)   main.cpp -fopenmp=libomp -fopenmp-targets=powerpc64le-ibm-linux-gnu  -o
```
cjappl pushed a commit that referenced this pull request Aug 14, 2025
@MacDue @tstellar
[AArch64][SME] Spill p-regs as z-regs when streaming hazards are poss…
1951944 
…ible (llvm#123752)

This patch adds a new option `-aarch64-enable-zpr-predicate-spills`
(which is disabled by default), this option replaces predicate spills
with vector spills in streaming[-compatible] functions.

For example:

```
str	p8, [sp, #7, mul vl]            // 2-byte Folded Spill
// ...
ldr	p8, [sp, #7, mul vl]            // 2-byte Folded Reload
```

Becomes:

```
mov	z0.b, p8/z, #1
str	z0, [sp]                        // 16-byte Folded Spill
// ...
ldr	z0, [sp]                        // 16-byte Folded Reload
ptrue	p4.b
cmpne	p8.b, p4/z, z0.b, #0
```

This is done to avoid streaming memory hazards between FPR/vector and
predicate spills, which currently occupy the same stack area even when
the `-aarch64-stack-hazard-size` flag is set.

This is implemented with two new pseudos SPILL_PPR_TO_ZPR_SLOT_PSEUDO
and FILL_PPR_FROM_ZPR_SLOT_PSEUDO. The expansion of these pseudos
handles scavenging the required registers (z0 in the above example) and,
in the worst case spilling a register to an emergency stack slot in the
expansion. The condition flags are also preserved around the `cmpne` in
case they are live at the expansion point.
cjappl pushed a commit that referenced this pull request Aug 14, 2025
@anutosh491 @tstellar
[clang-repl] : Fix clang-repl crash with --cuda flag (llvm#136404)
c877757 
`clang-repl --cuda` was previously crashing with a segmentation fault,
instead of reporting a clean error
```
(base) anutosh491@Anutoshs-MacBook-Air bin % ./clang-repl --cuda
#0 0x0000000111da4fbc llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/local/libexec/llvm-20/lib/libLLVM.dylib+0x150fbc)
#1 0x0000000111da31dc llvm::sys::RunSignalHandlers() (/opt/local/libexec/llvm-20/lib/libLLVM.dylib+0x14f1dc)
#2 0x0000000111da5628 SignalHandler(int) (/opt/local/libexec/llvm-20/lib/libLLVM.dylib+0x151628)
#3 0x000000019b242de4 (/usr/lib/system/libsystem_platform.dylib+0x180482de4)
#4 0x0000000107f638d0 clang::IncrementalCUDADeviceParser::IncrementalCUDADeviceParser(std::__1::unique_ptr<clang::CompilerInstance, std::__1::default_delete<clang::CompilerInstance>>, clang::CompilerInstance&, llvm::IntrusiveRefCntPtr<llvm::vfs::InMemoryFileSystem>, llvm::Error&, std::__1::list<clang::PartialTranslationUnit, std::__1::allocator<clang::PartialTranslationUnit>> const&) (/opt/local/libexec/llvm-20/lib/libclang-cpp.dylib+0x216b8d0)
#5 0x0000000107f638d0 clang::IncrementalCUDADeviceParser::IncrementalCUDADeviceParser(std::__1::unique_ptr<clang::CompilerInstance, std::__1::default_delete<clang::CompilerInstance>>, clang::CompilerInstance&, llvm::IntrusiveRefCntPtr<llvm::vfs::InMemoryFileSystem>, llvm::Error&, std::__1::list<clang::PartialTranslationUnit, std::__1::allocator<clang::PartialTranslationUnit>> const&) (/opt/local/libexec/llvm-20/lib/libclang-cpp.dylib+0x216b8d0)
#6 0x0000000107f6bac8 clang::Interpreter::createWithCUDA(std::__1::unique_ptr<clang::CompilerInstance, std::__1::default_delete<clang::CompilerInstance>>, std::__1::unique_ptr<clang::CompilerInstance, std::__1::default_delete<clang::CompilerInstance>>) (/opt/local/libexec/llvm-20/lib/libclang-cpp.dylib+0x2173ac8)
#7 0x000000010206f8a8 main (/opt/local/libexec/llvm-20/bin/clang-repl+0x1000038a8)
#8 0x000000019ae8c274
Segmentation fault: 11
```

The underlying issue was that the `DeviceCompilerInstance` (used for
device-side CUDA compilation) was never initialized with a `Sema`, which
is required before constructing the `IncrementalCUDADeviceParser`.

https://github.com/llvm/llvm-project/blob/89687e6f383b742a3c6542dc673a84d9f82d02de/clang/lib/Interpreter/DeviceOffload.cpp#L32

https://github.com/llvm/llvm-project/blob/89687e6f383b742a3c6542dc673a84d9f82d02de/clang/lib/Interpreter/IncrementalParser.cpp#L31

Unlike the host-side `CompilerInstance` which runs `ExecuteAction`
inside the Interpreter constructor (thereby setting up Sema), the
device-side CI was passed into the parser uninitialized, leading to an
assertion or crash when accessing its internals.

To fix this, I refactored the `Interpreter::create` method to include an
optional `DeviceCI` parameter. If provided, we know we need to take care
of this instance too. Only then do we construct the
`IncrementalCUDADeviceParser`.

(cherry picked from commit 21fb19f)
cjappl pushed a commit that referenced this pull request Aug 14, 2025
@anutosh491 @tstellar
[clang-repl] Fix destructor for interpreter for the cuda negation case (
2b34040 
llvm#138091)

Check this error for more context
(https://github.com/compiler-research/CppInterOp/actions/runs/14749797085/job/41407625681?pr=491#step:10:531)

This fails with
```
* thread #1, name = 'CppInterOpTests', stop reason = signal SIGSEGV: address not mapped to object (fault address: 0x55500356d6d3)
  * frame #0: 0x00007fffee41cfe3 libclangCppInterOp.so.21.0gitclang::PragmaNamespace::~PragmaNamespace() + 99
    frame #1: 0x00007fffee435666 libclangCppInterOp.so.21.0gitclang::Preprocessor::~Preprocessor() + 3830
    frame #2: 0x00007fffee20917a libclangCppInterOp.so.21.0gitstd::_Sp_counted_base<(__gnu_cxx::_Lock_policy)2>::_M_release() + 58
    frame #3: 0x00007fffee224796 libclangCppInterOp.so.21.0gitclang::CompilerInstance::~CompilerInstance() + 838
    frame #4: 0x00007fffee22494d libclangCppInterOp.so.21.0gitclang::CompilerInstance::~CompilerInstance() + 13
    frame #5: 0x00007fffed95ec62 libclangCppInterOp.so.21.0gitclang::IncrementalCUDADeviceParser::~IncrementalCUDADeviceParser() + 98
    frame #6: 0x00007fffed9551b6 libclangCppInterOp.so.21.0gitclang::Interpreter::~Interpreter() + 102
    frame #7: 0x00007fffed95598d libclangCppInterOp.so.21.0gitclang::Interpreter::~Interpreter() + 13
    frame #8: 0x00007fffed9181e7 libclangCppInterOp.so.21.0gitcompat::createClangInterpreter(std::vector<char const*, std::allocator<char const*>>&) + 2919
```

Problem :

1) The destructor currently handles no clearance for the DeviceParser
and the DeviceAct. We currently only have this

https://github.com/llvm/llvm-project/blob/976493822443c52a71ed3c67aaca9a555b20c55d/clang/lib/Interpreter/Interpreter.cpp#L416-L419

2) The ownership for DeviceCI currently is present in
IncrementalCudaDeviceParser. But this should be similar to how the
combination for hostCI, hostAction and hostParser are managed by the
Interpreter. As on master the DeviceAct and DeviceParser are managed by
the Interpreter but not DeviceCI. This is problematic because :
IncrementalParser holds a Sema& which points into the DeviceCI. On
master, DeviceCI is destroyed before the base class ~IncrementalParser()
runs, causing Parser::reset() to access a dangling Sema (and as Sema
holds a reference to Preprocessor which owns PragmaNamespace) we see
this
```
  * frame #0: 0x00007fffee41cfe3 libclangCppInterOp.so.21.0gitclang::PragmaNamespace::~PragmaNamespace() + 99
    frame #1: 0x00007fffee435666 libclangCppInterOp.so.21.0gitclang::Preprocessor::~Preprocessor() + 3830

```

(cherry picked from commit 529b6fc)
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@cjappl