[clang] [llvm] [ARM] Introduce intrinsics for MVE fma under strict-fp. (PR #169771)

Sun Nov 30 06:49:19 PST 2025

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-s390x-linux-lnt` running on `systemz-1` while building `clang,llvm` at step 7 "ninja check 1".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/136/builds/6132

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 7 (ninja check 1) failure: stage 1 checked (failure)
******************** TEST 'LLVM :: CodeGen/RISCV/atomic-rmw.ll' FAILED ********************
Exit Code: 2

Command Output (stdout):
--
# RUN: at line 2
/home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc -mtriple=riscv32 -verify-machineinstrs < /home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/llvm/llvm/test/CodeGen/RISCV/atomic-rmw.ll    | /home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/FileCheck -check-prefix=RV32I /home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/llvm/llvm/test/CodeGen/RISCV/atomic-rmw.ll
# executed command: /home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc -mtriple=riscv32 -verify-machineinstrs
# executed command: /home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/FileCheck -check-prefix=RV32I /home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/llvm/llvm/test/CodeGen/RISCV/atomic-rmw.ll
# RUN: at line 4
/home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc -mtriple=riscv32 -mattr=+zalrsc -verify-machineinstrs < /home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/llvm/llvm/test/CodeGen/RISCV/atomic-rmw.ll    | /home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/FileCheck -check-prefixes=RV32I-ZALRSC /home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/llvm/llvm/test/CodeGen/RISCV/atomic-rmw.ll
# executed command: /home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc -mtriple=riscv32 -mattr=+zalrsc -verify-machineinstrs
# .---command stderr------------
# | LLVM ERROR: Cannot select: intrinsic %llvm.riscv.masked.atomicrmw.xchg
# | 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: /home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc -mtriple=riscv32 -mattr=+zalrsc -verify-machineinstrs
# | 1.	Running pass 'Function Pass Manager' on module '<stdin>'.
# | 2.	Running pass 'RISC-V DAG->DAG Pattern Instruction Selection' on function '@atomicrmw_xchg_i8_monotonic'
# |  #0 0x000002aa336b8292 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc+0x45b8292)
# |  #1 0x000002aa336b51e6 llvm::sys::RunSignalHandlers() (/home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc+0x45b51e6)
# |  #2 0x000002aa336b5388 SignalHandler(int, siginfo_t*, void*) Signals.cpp:0:0
# |  #3 0x000003ffabd7e480 (linux-vdso64.so.1+0x480)
# |  #4 0x000003ffab698116 __pthread_kill_implementation ./nptl/pthread_kill.c:44:76
# |  #5 0x000003ffab648ac0 raise ./signal/../sysdeps/posix/raise.c:27:3
# |  #6 0x000003ffab62a460 abort ./stdlib/abort.c:81:7
# |  #7 0x000002aa335e2e62 (/home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc+0x44e2e62)
# |  #8 0x000002aa333e5cde llvm::SelectionDAGISel::CannotYetSelect(llvm::SDNode*) (/home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc+0x42e5cde)
# |  #9 0x000002aa333e7e74 llvm::SelectionDAGISel::SelectCodeCommon(llvm::SDNode*, unsigned char const*, unsigned int) (/home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc+0x42e7e74)
# | #10 0x000002aa30fdde54 llvm::RISCVDAGToDAGISel::Select(llvm::SDNode*) (/home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc+0x1edde54)
# | #11 0x000002aa333e0dba llvm::SelectionDAGISel::DoInstructionSelection() (/home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc+0x42e0dba)
# | #12 0x000002aa333f2bc6 llvm::SelectionDAGISel::CodeGenAndEmitDAG() (/home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc+0x42f2bc6)
# | #13 0x000002aa333f60ac llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) (/home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc+0x42f60ac)
# | #14 0x000002aa333f7b28 llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) (/home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc+0x42f7b28)
# | #15 0x000002aa333e0590 llvm::SelectionDAGISelLegacy::runOnMachineFunction(llvm::MachineFunction&) (/home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc+0x42e0590)
# | #16 0x000002aa32393d26 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (.part.0) MachineFunctionPass.cpp:0:0
# | #17 0x000002aa32aba5e0 llvm::FPPassManager::runOnFunction(llvm::Function&) (/home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc+0x39ba5e0)
# | #18 0x000002aa32abaa9c llvm::FPPassManager::runOnModule(llvm::Module&) (/home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc+0x39baa9c)
# | #19 0x000002aa32abb4fc llvm::legacy::PassManagerImpl::run(llvm::Module&) (/home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc+0x39bb4fc)
# | #20 0x000002aa2f8d03f2 compileModule(char**, llvm::LLVMContext&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>&) llc.cpp:0:0
# | #21 0x000002aa2f7a4176 main (/home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc+0x6a4176)
# | #22 0x000003ffab62a712 __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:74:3
# | #23 0x000003ffab62a7f0 call_init ./csu/../csu/libc-start.c:128:20
# | #24 0x000003ffab62a7f0 __libc_start_main ./csu/../csu/libc-start.c:379:5
# | #25 0x000002aa2f8c4e30 _start (/home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/llc+0x7c4e30)
# `-----------------------------
# error: command failed with exit status: -6
# executed command: /home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/stage1/bin/FileCheck -check-prefixes=RV32I-ZALRSC /home/uweigand/sandbox/buildbot/clang-s390x-linux-lnt/llvm/llvm/test/CodeGen/RISCV/atomic-rmw.ll
# .---command stderr------------
# | FileCheck error: '<stdin>' is empty.
...

```

</details>

https://github.com/llvm/llvm-project/pull/169771