[llvm] [RISCV] Recognize VLA shift pairs from shuffle masks (PR #127710)

Thu Feb 20 07:57:28 PST 2025

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `libc-x86_64-debian-dbg-bootstrap-build` running on `libc-x86_64-debian` while building `llvm` at step 4 "annotate".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/200/builds/3977

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

```
Step 4 (annotate) failure: 'python ../llvm-zorg/zorg/buildbot/builders/annotated/libc-linux.py ...' (failure)
...
[3/39] Building CXX object tools/clang/lib/Basic/CMakeFiles/obj.clangBasic.dir/Version.cpp.o
[4/39] Building CXX object tools/llvm-config/CMakeFiles/llvm-config.dir/llvm-config.cpp.o
[5/39] Linking CXX executable bin/llvm-config
[6/39] Building CXX object lib/Object/CMakeFiles/LLVMObject.dir/IRSymtab.cpp.o
[7/39] Linking CXX static library lib/libLLVMObject.a
[8/39] Linking CXX static library lib/libclangBasic.a
[9/39] Linking CXX executable bin/llvm-size
[10/39] Linking CXX executable bin/llvm-objcopy
[11/39] Generating ../../bin/llvm-strip
[12/39] Building CXX object lib/Target/RISCV/CMakeFiles/LLVMRISCVCodeGen.dir/RISCVISelLowering.cpp.o
FAILED: lib/Target/RISCV/CMakeFiles/LLVMRISCVCodeGen.dir/RISCVISelLowering.cpp.o 
/usr/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/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/build/lib/Target/RISCV -I/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/llvm-project/llvm/lib/Target/RISCV -I/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/build/include -I/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -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 -g -fvisibility=hidden  -fno-exceptions -funwind-tables -fno-rtti -std=c++17 -MD -MT lib/Target/RISCV/CMakeFiles/LLVMRISCVCodeGen.dir/RISCVISelLowering.cpp.o -MF lib/Target/RISCV/CMakeFiles/LLVMRISCVCodeGen.dir/RISCVISelLowering.cpp.o.d -o lib/Target/RISCV/CMakeFiles/LLVMRISCVCodeGen.dir/RISCVISelLowering.cpp.o -c /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/llvm-project/llvm/lib/Target/RISCV/RISCVISelLowering.cpp
/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/llvm-project/llvm/lib/Target/RISCV/RISCVISelLowering.cpp:5723:24: error: reference to local binding 'TrueMask' declared in enclosing function 'lowerVECTOR_SHUFFLE'
        assert(Mask == TrueMask);
                       ^
/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/llvm-project/llvm/lib/Target/RISCV/RISCVISelLowering.cpp:5476:9: note: 'TrueMask' declared here
  auto [TrueMask, VL] = getDefaultVLOps(VT, ContainerVT, DL, DAG, Subtarget);
        ^
/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/llvm-project/llvm/lib/Target/RISCV/RISCVISelLowering.cpp:5728:76: error: reference to local binding 'VL' declared in enclosing function 'lowerVECTOR_SHUFFLE'
                             DAG.getConstant(-SlideAmt, DL, XLenVT), Mask, VL,
                                                                           ^
/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/llvm-project/llvm/lib/Target/RISCV/RISCVISelLowering.cpp:5476:19: note: 'VL' declared here
  auto [TrueMask, VL] = getDefaultVLOps(VT, ContainerVT, DL, DAG, Subtarget);
                  ^
/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/llvm-project/llvm/lib/Target/RISCV/RISCVISelLowering.cpp:5731:71: error: reference to local binding 'VL' declared in enclosing function 'lowerVECTOR_SHUFFLE'
                         DAG.getConstant(SlideAmt, DL, XLenVT), Mask, VL,
                                                                      ^
/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/llvm-project/llvm/lib/Target/RISCV/RISCVISelLowering.cpp:5476:19: note: 'VL' declared here
  auto [TrueMask, VL] = getDefaultVLOps(VT, ContainerVT, DL, DAG, Subtarget);
                  ^
3 errors generated.
[13/39] Linking CXX executable bin/sanstats
[14/39] Linking CXX executable bin/llvm-readobj
[15/39] Linking CXX executable bin/llvm-symbolizer
[16/39] Linking CXX executable bin/llvm-cov
[17/39] Linking CXX executable bin/llvm-xray
[18/39] Building CXX object lib/CodeGen/AsmPrinter/CMakeFiles/LLVMAsmPrinter.dir/AsmPrinter.cpp.o
[19/39] Linking CXX executable bin/obj2yaml
[20/39] Linking CXX executable bin/llvm-ar
[21/39] Linking CXX executable bin/llvm-profdata
[22/39] Linking CXX executable bin/sancov
[23/39] Linking CXX executable bin/llvm-nm
[24/39] Linking CXX executable bin/llvm-objdump
[25/39] Building CXX object lib/LTO/CMakeFiles/LLVMLTO.dir/LTO.cpp.o
[26/39] Linking CXX executable bin/llvm-jitlink
ninja: build stopped: subcommand failed.
['ninja', 'libc'] exited with return code 1.
The build step threw an exception...
Traceback (most recent call last):
Step 6 (build libc) failure: build libc (failure)
...
[3/39] Building CXX object tools/clang/lib/Basic/CMakeFiles/obj.clangBasic.dir/Version.cpp.o
[4/39] Building CXX object tools/llvm-config/CMakeFiles/llvm-config.dir/llvm-config.cpp.o
[5/39] Linking CXX executable bin/llvm-config
[6/39] Building CXX object lib/Object/CMakeFiles/LLVMObject.dir/IRSymtab.cpp.o
[7/39] Linking CXX static library lib/libLLVMObject.a
[8/39] Linking CXX static library lib/libclangBasic.a
[9/39] Linking CXX executable bin/llvm-size
[10/39] Linking CXX executable bin/llvm-objcopy
[11/39] Generating ../../bin/llvm-strip
[12/39] Building CXX object lib/Target/RISCV/CMakeFiles/LLVMRISCVCodeGen.dir/RISCVISelLowering.cpp.o
FAILED: lib/Target/RISCV/CMakeFiles/LLVMRISCVCodeGen.dir/RISCVISelLowering.cpp.o 
/usr/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/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/build/lib/Target/RISCV -I/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/llvm-project/llvm/lib/Target/RISCV -I/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/build/include -I/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -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 -g -fvisibility=hidden  -fno-exceptions -funwind-tables -fno-rtti -std=c++17 -MD -MT lib/Target/RISCV/CMakeFiles/LLVMRISCVCodeGen.dir/RISCVISelLowering.cpp.o -MF lib/Target/RISCV/CMakeFiles/LLVMRISCVCodeGen.dir/RISCVISelLowering.cpp.o.d -o lib/Target/RISCV/CMakeFiles/LLVMRISCVCodeGen.dir/RISCVISelLowering.cpp.o -c /home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/llvm-project/llvm/lib/Target/RISCV/RISCVISelLowering.cpp
/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/llvm-project/llvm/lib/Target/RISCV/RISCVISelLowering.cpp:5723:24: error: reference to local binding 'TrueMask' declared in enclosing function 'lowerVECTOR_SHUFFLE'
        assert(Mask == TrueMask);
                       ^
/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/llvm-project/llvm/lib/Target/RISCV/RISCVISelLowering.cpp:5476:9: note: 'TrueMask' declared here
  auto [TrueMask, VL] = getDefaultVLOps(VT, ContainerVT, DL, DAG, Subtarget);
        ^
/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/llvm-project/llvm/lib/Target/RISCV/RISCVISelLowering.cpp:5728:76: error: reference to local binding 'VL' declared in enclosing function 'lowerVECTOR_SHUFFLE'
                             DAG.getConstant(-SlideAmt, DL, XLenVT), Mask, VL,
                                                                           ^
/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/llvm-project/llvm/lib/Target/RISCV/RISCVISelLowering.cpp:5476:19: note: 'VL' declared here
  auto [TrueMask, VL] = getDefaultVLOps(VT, ContainerVT, DL, DAG, Subtarget);
                  ^
/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/llvm-project/llvm/lib/Target/RISCV/RISCVISelLowering.cpp:5731:71: error: reference to local binding 'VL' declared in enclosing function 'lowerVECTOR_SHUFFLE'
                         DAG.getConstant(SlideAmt, DL, XLenVT), Mask, VL,
                                                                      ^
/home/llvm-libc-buildbot/buildbot-worker/libc-x86_64-debian/libc-x86_64-debian-dbg-bootstrap-build/llvm-project/llvm/lib/Target/RISCV/RISCVISelLowering.cpp:5476:19: note: 'VL' declared here
  auto [TrueMask, VL] = getDefaultVLOps(VT, ContainerVT, DL, DAG, Subtarget);
                  ^
3 errors generated.
[13/39] Linking CXX executable bin/sanstats
[14/39] Linking CXX executable bin/llvm-readobj
[15/39] Linking CXX executable bin/llvm-symbolizer
[16/39] Linking CXX executable bin/llvm-cov
[17/39] Linking CXX executable bin/llvm-xray
[18/39] Building CXX object lib/CodeGen/AsmPrinter/CMakeFiles/LLVMAsmPrinter.dir/AsmPrinter.cpp.o
[19/39] Linking CXX executable bin/obj2yaml
[20/39] Linking CXX executable bin/llvm-ar
[21/39] Linking CXX executable bin/llvm-profdata
[22/39] Linking CXX executable bin/sancov
[23/39] Linking CXX executable bin/llvm-nm
[24/39] Linking CXX executable bin/llvm-objdump
[25/39] Building CXX object lib/LTO/CMakeFiles/LLVMLTO.dir/LTO.cpp.o
[26/39] Linking CXX executable bin/llvm-jitlink
ninja: build stopped: subcommand failed.
['ninja', 'libc'] exited with return code 1.
The build step threw an exception...
Traceback (most recent call last):

```

</details>

https://github.com/llvm/llvm-project/pull/127710