[llvm] [VPlan] Add VPIRInstruction, use for exit block live-outs. (PR #100735)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `sanitizer-x86_64-linux-android` running on `sanitizer-buildbot-android` while building `llvm` at step 2 "annotate".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/186/builds/2329

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

```
Step 2 (annotate) failure: 'python ../sanitizer_buildbot/sanitizers/zorg/buildbot/builders/sanitizers/buildbot_selector.py' (failure)
...
[1389/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/SLPVectorizer.cpp.o
[1390/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/Vectorize.cpp.o
[1391/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/VectorCombine.cpp.o
[1392/5250] Building AArch64GenSubtargetInfo.inc...
[1393/5250] Building AArch64GenInstrInfo.inc...
[1394/5250] Building AMDGPUGenCallingConv.inc...
[1395/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/VPlanHCFGBuilder.cpp.o
[1396/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/VPlanAnalysis.cpp.o
[1397/5250] Building AMDGPUGenMCPseudoLowering.inc...
[1398/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/LoopVectorize.cpp.o
FAILED: lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/LoopVectorize.cpp.o 
CCACHE_CPP2=yes CCACHE_HASHDIR=yes /usr/bin/ccache /var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm_build0/bin/clang++ -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm_build64/lib/Transforms/Vectorize -I/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm-project/llvm/lib/Transforms/Vectorize -I/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm_build64/include -I/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -O3 -DNDEBUG -std=c++17  -fno-exceptions -funwind-tables -fno-rtti -UNDEBUG -MD -MT lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/LoopVectorize.cpp.o -MF lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/LoopVectorize.cpp.o.d -o lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/LoopVectorize.cpp.o -c /var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm-project/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm-project/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp:8729:15: error: variable 'ExitBB' set but not used [-Werror,-Wunused-but-set-variable]
 8729 |   BasicBlock *ExitBB = nullptr;
      |               ^
1 error generated.
[1399/5250] Building AMDGPUGenPostLegalizeGICombiner.inc...
[1400/5250] Building AMDGPUGenMCCodeEmitter.inc...
[1401/5250] Building AMDGPUGenDisassemblerTables.inc...
[1402/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/VPlan.cpp.o
[1403/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/VPlanSLP.cpp.o
[1404/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/VPlanVerifier.cpp.o
[1405/5250] Building AMDGPUGenAsmWriter.inc...
[1406/5250] Building AMDGPUGenGlobalISel.inc...
[1407/5250] Building AMDGPUGenAsmMatcher.inc...
[1408/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/VPlanRecipes.cpp.o
[1409/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/VPlanTransforms.cpp.o
[1410/5250] Building AMDGPUGenInstrInfo.inc...
[1411/5250] Building AMDGPUGenDAGISel.inc...
ninja: build stopped: subcommand failed.

How to reproduce locally: https://github.com/google/sanitizers/wiki/SanitizerBotReproduceBuild

@@@STEP_FAILURE@@@
Step 8 (bootstrap clang) failure: bootstrap clang (failure)
...
[1389/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/SLPVectorizer.cpp.o
[1390/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/Vectorize.cpp.o
[1391/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/VectorCombine.cpp.o
[1392/5250] Building AArch64GenSubtargetInfo.inc...
[1393/5250] Building AArch64GenInstrInfo.inc...
[1394/5250] Building AMDGPUGenCallingConv.inc...
[1395/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/VPlanHCFGBuilder.cpp.o
[1396/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/VPlanAnalysis.cpp.o
[1397/5250] Building AMDGPUGenMCPseudoLowering.inc...
[1398/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/LoopVectorize.cpp.o
FAILED: lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/LoopVectorize.cpp.o 
CCACHE_CPP2=yes CCACHE_HASHDIR=yes /usr/bin/ccache /var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm_build0/bin/clang++ -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm_build64/lib/Transforms/Vectorize -I/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm-project/llvm/lib/Transforms/Vectorize -I/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm_build64/include -I/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -O3 -DNDEBUG -std=c++17  -fno-exceptions -funwind-tables -fno-rtti -UNDEBUG -MD -MT lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/LoopVectorize.cpp.o -MF lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/LoopVectorize.cpp.o.d -o lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/LoopVectorize.cpp.o -c /var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm-project/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm-project/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp:8729:15: error: variable 'ExitBB' set but not used [-Werror,-Wunused-but-set-variable]
 8729 |   BasicBlock *ExitBB = nullptr;
      |               ^
1 error generated.
[1399/5250] Building AMDGPUGenPostLegalizeGICombiner.inc...
[1400/5250] Building AMDGPUGenMCCodeEmitter.inc...
[1401/5250] Building AMDGPUGenDisassemblerTables.inc...
[1402/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/VPlan.cpp.o
[1403/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/VPlanSLP.cpp.o
[1404/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/VPlanVerifier.cpp.o
[1405/5250] Building AMDGPUGenAsmWriter.inc...
[1406/5250] Building AMDGPUGenGlobalISel.inc...
[1407/5250] Building AMDGPUGenAsmMatcher.inc...
[1408/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/VPlanRecipes.cpp.o
[1409/5250] Building CXX object lib/Transforms/Vectorize/CMakeFiles/LLVMVectorize.dir/VPlanTransforms.cpp.o
[1410/5250] Building AMDGPUGenInstrInfo.inc...
[1411/5250] Building AMDGPUGenDAGISel.inc...
ninja: build stopped: subcommand failed.

How to reproduce locally: https://github.com/google/sanitizers/wiki/SanitizerBotReproduceBuild
program finished with exit code 2
elapsedTime=94.730547

```

</details>

https://github.com/llvm/llvm-project/pull/100735