[llvm] [LLVM][TableGen] Parameterize NumToSkip in DecoderEmitter (PR #135882)

Wed Apr 16 20:04:31 PDT 2025

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-x64-windows-msvc` running on `windows-gcebot2` while building `llvm` at step 4 "annotate".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/63/builds/5164

<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/clang-windows.py ...' (failure)
...
[1921/6301] Building AArch64GenExegesis.inc...
[1922/6301] Building AArch64GenAsmMatcher.inc...
[1923/6301] Building AArch64GenAsmWriter1.inc...
[1924/6301] Building AArch64GenCallingConv.inc...
[1925/6301] Building AArch64GenMCPseudoLowering.inc...
[1926/6301] Building AArch64GenPostLegalizeGICombiner.inc...
[1927/6301] Building CXX object lib\ExecutionEngine\Orc\TargetProcess\CMakeFiles\LLVMOrcTargetProcess.dir\OrcRTBootstrap.cpp.obj
[1928/6301] Building AArch64GenAsmWriter.inc...
[1929/6301] Building CXX object lib\ExecutionEngine\Orc\CMakeFiles\LLVMOrcJIT.dir\MachOPlatform.cpp.obj
[1930/6301] Building AArch64GenDisassemblerTables.inc...
FAILED: lib/Target/AArch64/AArch64GenDisassemblerTables.inc C:/b/slave/clang-x64-windows-msvc/build/stage2/lib/Target/AArch64/AArch64GenDisassemblerTables.inc 
cmd.exe /C "cd /D C:\b\slave\clang-x64-windows-msvc\build\stage2 && C:\b\slave\clang-x64-windows-msvc\build\stage2\bin\llvm-tblgen.exe -gen-disassembler --num-to-skip-size=3 -I C:/b/slave/clang-x64-windows-msvc/llvm-project/llvm/lib/Target/AArch64 -IC:/b/slave/clang-x64-windows-msvc/build/stage2/include -IC:/b/slave/clang-x64-windows-msvc/llvm-project/llvm/include -I C:/b/slave/clang-x64-windows-msvc/llvm-project/llvm/lib/Target --long-string-literals=0 C:/b/slave/clang-x64-windows-msvc/llvm-project/llvm/lib/Target/AArch64/AArch64.td --write-if-changed -o lib/Target/AArch64/AArch64GenDisassemblerTables.inc -d lib/Target/AArch64/AArch64GenDisassemblerTables.inc.d"
Assertion failed: DestIdx > FixupIdx + NumToSkipSizeInBytes && "Expecting a forward jump in the decoding table", file C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\utils\TableGen\DecoderEmitter.cpp, line 151
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.	Program arguments: C:\\b\\slave\\clang-x64-windows-msvc\\build\\stage2\\bin\\llvm-tblgen.exe -gen-disassembler --num-to-skip-size=3 -I C:/b/slave/clang-x64-windows-msvc/llvm-project/llvm/lib/Target/AArch64 -IC:/b/slave/clang-x64-windows-msvc/build/stage2/include -IC:/b/slave/clang-x64-windows-msvc/llvm-project/llvm/include -I C:/b/slave/clang-x64-windows-msvc/llvm-project/llvm/lib/Target --long-string-literals=0 C:/b/slave/clang-x64-windows-msvc/llvm-project/llvm/lib/Target/AArch64/AArch64.td --write-if-changed -o lib/Target/AArch64/AArch64GenDisassemblerTables.inc -d lib/Target/AArch64/AArch64GenDisassemblerTables.inc.d
Exception Code: 0xC000001D
 #0 0x00007ff68442c206 HandleAbort C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\lib\Support\Windows\Signals.inc:429:0
 #1 0x00007ffe7a68d167 (C:\windows\SYSTEM32\ucrtbase.DLL+0x6d167)
 #2 0x00007ffe7a68dff1 (C:\windows\SYSTEM32\ucrtbase.DLL+0x6dff1)
 #3 0x00007ffe7a68fca1 (C:\windows\SYSTEM32\ucrtbase.DLL+0x6fca1)
 #4 0x00007ffe7a68ffaf (C:\windows\SYSTEM32\ucrtbase.DLL+0x6ffaf)
 #5 0x00007ff68428779b `anonymous namespace'::FilterChooser::emitTableEntries C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\utils\TableGen\DecoderEmitter.cpp:1769:0
 #6 0x00007ff6842881f5 `anonymous namespace'::FilterChooser::emitTableEntries C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\utils\TableGen\DecoderEmitter.cpp:1771:0
 #7 0x00007ff6842840e0 `anonymous namespace'::DecoderEmitter::run C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\utils\TableGen\DecoderEmitter.cpp:2552:0
 #8 0x00007ff68427edc7 llvm::EmitDecoder(class llvm::RecordKeeper const &,class llvm::raw_ostream &,class llvm::StringRef) C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\utils\TableGen\DecoderEmitter.cpp:2584:0
 #9 0x00007ff6842a0d7c emitDisassembler C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\utils\TableGen\DisassemblerEmitter.cpp:130:0
#10 0x00007ff6843f6b53 llvm::TableGen::Emitter::ApplyCallback(class llvm::RecordKeeper const &,class llvm::raw_ostream &) C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\lib\TableGen\TableGenBackend.cpp:66:0
#11 0x00007ff68442415c llvm::TableGenMain(char const *,class std::function<bool (class llvm::raw_ostream &,class llvm::RecordKeeper const &)>) C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\lib\TableGen\Main.cpp:152:0
#12 0x00007ff6840db3e8 tblgen_main(int,char * *) C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\utils\TableGen\Basic\TableGen.cpp:74:0
#13 0x00007ff68447d170 __scrt_common_main_seh d:\agent\_work\63\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288:0
#14 0x00007ffe818c13f2 (C:\windows\system32\KERNEL32.DLL+0x13f2)
#15 0x00007ffe83da5504 (C:\windows\SYSTEM32\ntdll.dll+0x15504)
[1931/6301] Building AArch64GenRegisterBank.inc...
[1932/6301] Building AArch64GenO0PreLegalizeGICombiner.inc...
[1933/6301] Building AArch64GenFastISel.inc...
[1934/6301] Building CXX object lib\Target\CMakeFiles\LLVMTarget.dir\TargetMachine.cpp.obj
[1935/6301] Building AArch64GenPostLegalizeGILowering.inc...
[1936/6301] Building AArch64GenPreLegalizeGICombiner.inc...
[1937/6301] Building AArch64GenMCCodeEmitter.inc...
[1938/6301] Building AArch64GenSystemOperands.inc...
[1939/6301] Building AArch64GenGlobalISel.inc...
[1940/6301] Building AArch64GenRegisterInfo.inc...
[1941/6301] Building CXX object lib\ExecutionEngine\Orc\CMakeFiles\LLVMOrcJIT.dir\COFFPlatform.cpp.obj
[1942/6301] Building CXX object lib\ExecutionEngine\RuntimeDyld\CMakeFiles\LLVMRuntimeDyld.dir\RuntimeDyld.cpp.obj
[1943/6301] Building CXX object lib\ExecutionEngine\Orc\Debugging\CMakeFiles\LLVMOrcDebugging.dir\DebuggerSupport.cpp.obj
[1944/6301] Building CXX object lib\ExecutionEngine\Orc\Debugging\CMakeFiles\LLVMOrcDebugging.dir\DebugInfoSupport.cpp.obj
[1945/6301] Building AArch64GenDAGISel.inc...
[1946/6301] Building CXX object lib\ExecutionEngine\Orc\CMakeFiles\LLVMOrcJIT.dir\ExecutionUtils.cpp.obj
Step 11 (stage 2 build) failure: stage 2 build (failure)
...
[1921/6301] Building AArch64GenExegesis.inc...
[1922/6301] Building AArch64GenAsmMatcher.inc...
[1923/6301] Building AArch64GenAsmWriter1.inc...
[1924/6301] Building AArch64GenCallingConv.inc...
[1925/6301] Building AArch64GenMCPseudoLowering.inc...
[1926/6301] Building AArch64GenPostLegalizeGICombiner.inc...
[1927/6301] Building CXX object lib\ExecutionEngine\Orc\TargetProcess\CMakeFiles\LLVMOrcTargetProcess.dir\OrcRTBootstrap.cpp.obj
[1928/6301] Building AArch64GenAsmWriter.inc...
[1929/6301] Building CXX object lib\ExecutionEngine\Orc\CMakeFiles\LLVMOrcJIT.dir\MachOPlatform.cpp.obj
[1930/6301] Building AArch64GenDisassemblerTables.inc...
FAILED: lib/Target/AArch64/AArch64GenDisassemblerTables.inc C:/b/slave/clang-x64-windows-msvc/build/stage2/lib/Target/AArch64/AArch64GenDisassemblerTables.inc 
cmd.exe /C "cd /D C:\b\slave\clang-x64-windows-msvc\build\stage2 && C:\b\slave\clang-x64-windows-msvc\build\stage2\bin\llvm-tblgen.exe -gen-disassembler --num-to-skip-size=3 -I C:/b/slave/clang-x64-windows-msvc/llvm-project/llvm/lib/Target/AArch64 -IC:/b/slave/clang-x64-windows-msvc/build/stage2/include -IC:/b/slave/clang-x64-windows-msvc/llvm-project/llvm/include -I C:/b/slave/clang-x64-windows-msvc/llvm-project/llvm/lib/Target --long-string-literals=0 C:/b/slave/clang-x64-windows-msvc/llvm-project/llvm/lib/Target/AArch64/AArch64.td --write-if-changed -o lib/Target/AArch64/AArch64GenDisassemblerTables.inc -d lib/Target/AArch64/AArch64GenDisassemblerTables.inc.d"
Assertion failed: DestIdx > FixupIdx + NumToSkipSizeInBytes && "Expecting a forward jump in the decoding table", file C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\utils\TableGen\DecoderEmitter.cpp, line 151
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.	Program arguments: C:\\b\\slave\\clang-x64-windows-msvc\\build\\stage2\\bin\\llvm-tblgen.exe -gen-disassembler --num-to-skip-size=3 -I C:/b/slave/clang-x64-windows-msvc/llvm-project/llvm/lib/Target/AArch64 -IC:/b/slave/clang-x64-windows-msvc/build/stage2/include -IC:/b/slave/clang-x64-windows-msvc/llvm-project/llvm/include -I C:/b/slave/clang-x64-windows-msvc/llvm-project/llvm/lib/Target --long-string-literals=0 C:/b/slave/clang-x64-windows-msvc/llvm-project/llvm/lib/Target/AArch64/AArch64.td --write-if-changed -o lib/Target/AArch64/AArch64GenDisassemblerTables.inc -d lib/Target/AArch64/AArch64GenDisassemblerTables.inc.d
Exception Code: 0xC000001D
 #0 0x00007ff68442c206 HandleAbort C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\lib\Support\Windows\Signals.inc:429:0
 #1 0x00007ffe7a68d167 (C:\windows\SYSTEM32\ucrtbase.DLL+0x6d167)
 #2 0x00007ffe7a68dff1 (C:\windows\SYSTEM32\ucrtbase.DLL+0x6dff1)
 #3 0x00007ffe7a68fca1 (C:\windows\SYSTEM32\ucrtbase.DLL+0x6fca1)
 #4 0x00007ffe7a68ffaf (C:\windows\SYSTEM32\ucrtbase.DLL+0x6ffaf)
 #5 0x00007ff68428779b `anonymous namespace'::FilterChooser::emitTableEntries C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\utils\TableGen\DecoderEmitter.cpp:1769:0
 #6 0x00007ff6842881f5 `anonymous namespace'::FilterChooser::emitTableEntries C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\utils\TableGen\DecoderEmitter.cpp:1771:0
 #7 0x00007ff6842840e0 `anonymous namespace'::DecoderEmitter::run C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\utils\TableGen\DecoderEmitter.cpp:2552:0
 #8 0x00007ff68427edc7 llvm::EmitDecoder(class llvm::RecordKeeper const &,class llvm::raw_ostream &,class llvm::StringRef) C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\utils\TableGen\DecoderEmitter.cpp:2584:0
 #9 0x00007ff6842a0d7c emitDisassembler C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\utils\TableGen\DisassemblerEmitter.cpp:130:0
#10 0x00007ff6843f6b53 llvm::TableGen::Emitter::ApplyCallback(class llvm::RecordKeeper const &,class llvm::raw_ostream &) C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\lib\TableGen\TableGenBackend.cpp:66:0
#11 0x00007ff68442415c llvm::TableGenMain(char const *,class std::function<bool (class llvm::raw_ostream &,class llvm::RecordKeeper const &)>) C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\lib\TableGen\Main.cpp:152:0
#12 0x00007ff6840db3e8 tblgen_main(int,char * *) C:\b\slave\clang-x64-windows-msvc\llvm-project\llvm\utils\TableGen\Basic\TableGen.cpp:74:0
#13 0x00007ff68447d170 __scrt_common_main_seh d:\agent\_work\63\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288:0
#14 0x00007ffe818c13f2 (C:\windows\system32\KERNEL32.DLL+0x13f2)
#15 0x00007ffe83da5504 (C:\windows\SYSTEM32\ntdll.dll+0x15504)
[1931/6301] Building AArch64GenRegisterBank.inc...
[1932/6301] Building AArch64GenO0PreLegalizeGICombiner.inc...
[1933/6301] Building AArch64GenFastISel.inc...
[1934/6301] Building CXX object lib\Target\CMakeFiles\LLVMTarget.dir\TargetMachine.cpp.obj
[1935/6301] Building AArch64GenPostLegalizeGILowering.inc...
[1936/6301] Building AArch64GenPreLegalizeGICombiner.inc...
[1937/6301] Building AArch64GenMCCodeEmitter.inc...
[1938/6301] Building AArch64GenSystemOperands.inc...
[1939/6301] Building AArch64GenGlobalISel.inc...
[1940/6301] Building AArch64GenRegisterInfo.inc...
[1941/6301] Building CXX object lib\ExecutionEngine\Orc\CMakeFiles\LLVMOrcJIT.dir\COFFPlatform.cpp.obj
[1942/6301] Building CXX object lib\ExecutionEngine\RuntimeDyld\CMakeFiles\LLVMRuntimeDyld.dir\RuntimeDyld.cpp.obj
[1943/6301] Building CXX object lib\ExecutionEngine\Orc\Debugging\CMakeFiles\LLVMOrcDebugging.dir\DebuggerSupport.cpp.obj
[1944/6301] Building CXX object lib\ExecutionEngine\Orc\Debugging\CMakeFiles\LLVMOrcDebugging.dir\DebugInfoSupport.cpp.obj
[1945/6301] Building AArch64GenDAGISel.inc...
[1946/6301] Building CXX object lib\ExecutionEngine\Orc\CMakeFiles\LLVMOrcJIT.dir\ExecutionUtils.cpp.obj

```

</details>

https://github.com/llvm/llvm-project/pull/135882