[llvm] [SelectionDAG][RISCV] Support STACK/PATCHPOINT in SoftenFloatOperand. (PR #165922)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `lld-x86_64-ubuntu-fast` running on `as-builder-4` while building `llvm` at step 6 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/33/builds/25728

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

```
Step 6 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'LLVM :: CodeGen/RISCV/rv64-stackmap.ll' FAILED ********************
Exit Code: 2

Command Output (stdout):
--
# RUN: at line 1
/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc -mtriple=riscv64 < /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/llvm-project/llvm/test/CodeGen/RISCV/rv64-stackmap.ll | /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/FileCheck /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/llvm-project/llvm/test/CodeGen/RISCV/rv64-stackmap.ll
# executed command: /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc -mtriple=riscv64
# .---command stderr------------
# | llc: /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/llvm-project/llvm/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp:3814: bool llvm::DAGTypeLegalizer::SoftPromoteHalfOperand(llvm::SDNode*, unsigned int): Assertion `Res.getNode() != N && "Expected a new node!"' 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: /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc -mtriple=riscv64
# | 1.	Running pass 'Function Pass Manager' on module '<stdin>'.
# | 2.	Running pass 'RISC-V DAG->DAG Pattern Instruction Selection' on function '@floats'
# |  #0 0x0000612b99991e32 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc+0x412ae32)
# |  #1 0x0000612b9998eb2f llvm::sys::RunSignalHandlers() (/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc+0x4127b2f)
# |  #2 0x0000612b9998ec7c SignalHandler(int, siginfo_t*, void*) Signals.cpp:0:0
# |  #3 0x0000742d76a45330 (/lib/x86_64-linux-gnu/libc.so.6+0x45330)
# |  #4 0x0000742d76a9eb2c pthread_kill (/lib/x86_64-linux-gnu/libc.so.6+0x9eb2c)
# |  #5 0x0000742d76a4527e raise (/lib/x86_64-linux-gnu/libc.so.6+0x4527e)
# |  #6 0x0000742d76a288ff abort (/lib/x86_64-linux-gnu/libc.so.6+0x288ff)
# |  #7 0x0000742d76a2881b (/lib/x86_64-linux-gnu/libc.so.6+0x2881b)
# |  #8 0x0000742d76a3b517 (/lib/x86_64-linux-gnu/libc.so.6+0x3b517)
# |  #9 0x0000612b998271da (/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc+0x3fc01da)
# | #10 0x0000612b99798b31 llvm::DAGTypeLegalizer::run() (/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc+0x3f31b31)
# | #11 0x0000612b99799d58 llvm::SelectionDAG::LegalizeTypes() (/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc+0x3f32d58)
# | #12 0x0000612b996fab6f llvm::SelectionDAGISel::CodeGenAndEmitDAG() (/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc+0x3e93b6f)
# | #13 0x0000612b996ff1c6 llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) (/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc+0x3e981c6)
# | #14 0x0000612b997007f6 llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) (/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc+0x3e997f6)
# | #15 0x0000612b996ea837 llvm::SelectionDAGISelLegacy::runOnMachineFunction(llvm::MachineFunction&) (/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc+0x3e83837)
# | #16 0x0000612b987a05d3 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (.part.0) MachineFunctionPass.cpp:0:0
# | #17 0x0000612b98e4789e llvm::FPPassManager::runOnFunction(llvm::Function&) (/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc+0x35e089e)
# | #18 0x0000612b98e47ce1 llvm::FPPassManager::runOnModule(llvm::Module&) (/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc+0x35e0ce1)
# | #19 0x0000612b98e48632 llvm::legacy::PassManagerImpl::run(llvm::Module&) (/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc+0x35e1632)
# | #20 0x0000612b9605d0cb compileModule(char**, llvm::LLVMContext&) llc.cpp:0:0
# | #21 0x0000612b95f037ef main (/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc+0x69c7ef)
# | #22 0x0000742d76a2a1ca (/lib/x86_64-linux-gnu/libc.so.6+0x2a1ca)
# | #23 0x0000742d76a2a28b __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2a28b)
# | #24 0x0000612b96051525 _start (/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc+0x7ea525)
# `-----------------------------
# error: command failed with exit status: -6
# executed command: /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/FileCheck /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/llvm-project/llvm/test/CodeGen/RISCV/rv64-stackmap.ll
# .---command stderr------------
# | FileCheck error: '<stdin>' is empty.
# | FileCheck command line:  /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/FileCheck /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/llvm-project/llvm/test/CodeGen/RISCV/rv64-stackmap.ll
# `-----------------------------
# error: command failed with exit status: 2

--
...

```

</details>

https://github.com/llvm/llvm-project/pull/165922