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

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-with-thin-lto-ubuntu` running on `as-worker-92` while building `llvm` at step 13 "test-stage2-compiler".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/127/builds/3039

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

```
Step 13 (test-stage2-compiler) failure: build (failure)
...
llvm-lit: /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/utils/lit/lit/llvm/config.py:520: note: using ld64.lld: /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/bin/ld64.lld
llvm-lit: /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/utils/lit/lit/llvm/config.py:520: note: using wasm-ld: /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/bin/wasm-ld
llvm-lit: /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/utils/lit/tests/lit.cfg:111: warning: Setting a timeout per test not supported. Requires the Python psutil module but it could not be found. Try installing it via pip or via your operating system's package manager.
 Some tests will be skipped and the --timeout command line argument will not work.
llvm-lit: /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/utils/lit/lit/llvm/config.py:520: note: using ld.lld: /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/bin/ld.lld
llvm-lit: /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/utils/lit/lit/llvm/config.py:520: note: using lld-link: /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/bin/lld-link
llvm-lit: /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/utils/lit/lit/llvm/config.py:520: note: using ld64.lld: /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/bin/ld64.lld
llvm-lit: /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/utils/lit/lit/llvm/config.py:520: note: using wasm-ld: /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/bin/wasm-ld
-- Testing: 84805 tests, 72 workers --
Testing:  0.. 10.. 20.. 30.. 40.. 50.. 60.. 70
FAIL: LLVM :: TableGen/FixedLenDecoderEmitter/conflict.td (62981 of 84805)
******************** TEST 'LLVM :: TableGen/FixedLenDecoderEmitter/conflict.td' FAILED ********************
Exit Code: 134

Command Output (stderr):
--
/home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/bin/llvm-tblgen -gen-disassembler -I /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/test/TableGen/FixedLenDecoderEmitter/../../../include /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/test/TableGen/FixedLenDecoderEmitter/conflict.td -o - 2>/home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/test/TableGen/FixedLenDecoderEmitter/Output/conflict.td.tmp # RUN: at line 1
+ /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/bin/llvm-tblgen -gen-disassembler -I /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/test/TableGen/FixedLenDecoderEmitter/../../../include /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/test/TableGen/FixedLenDecoderEmitter/conflict.td -o -
/home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/test/TableGen/FixedLenDecoderEmitter/Output/conflict.td.script: line 2: 3773583 Aborted                 (core dumped) /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/bin/llvm-tblgen -gen-disassembler -I /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/test/TableGen/FixedLenDecoderEmitter/../../../include /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/test/TableGen/FixedLenDecoderEmitter/conflict.td -o - 2> /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/test/TableGen/FixedLenDecoderEmitter/Output/conflict.td.tmp

--

********************
Testing:  0.. 10.. 20.. 30.. 40.. 50.. 60.. 70
FAIL: LLVM :: TableGen/trydecode-emission4.td (63328 of 84805)
******************** TEST 'LLVM :: TableGen/trydecode-emission4.td' FAILED ********************
Exit Code: 2

Command Output (stderr):
--
/home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/bin/llvm-tblgen -gen-disassembler --num-to-skip-size=3 -I /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/test/TableGen/../../include /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/test/TableGen/trydecode-emission4.td | /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/bin/FileCheck /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/test/TableGen/trydecode-emission4.td # RUN: at line 1
+ /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/bin/FileCheck /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/test/TableGen/trydecode-emission4.td
+ /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/bin/llvm-tblgen -gen-disassembler --num-to-skip-size=3 -I /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/test/TableGen/../../include /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/test/TableGen/trydecode-emission4.td
llvm-tblgen: /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/utils/TableGen/DecoderEmitter.cpp:151: void (anonymous namespace)::DecoderTable::patchNumToSkip(size_t, uint32_t): Assertion `DestIdx > FixupIdx + NumToSkipSizeInBytes && "Expecting a forward jump in the decoding table"' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.	Program arguments: /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/bin/llvm-tblgen -gen-disassembler --num-to-skip-size=3 -I /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/test/TableGen/../../include /home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/llvm-project/llvm/test/TableGen/trydecode-emission4.td
 #0 0x000056033b5e0cc8 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/bin/llvm-tblgen+0x35bcc8)
 #1 0x000056033b5de8ce llvm::sys::RunSignalHandlers() (/home/buildbot/as-worker-92/clang-with-thin-lto-ubuntu/build/stage2/bin/llvm-tblgen+0x3598ce)
 #2 0x000056033b5e1341 SignalHandler(int, siginfo_t*, void*) Signals.cpp:0:0
 #3 0x00007f4dfc4c3520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
 #4 0x00007f4dfc5179fc pthread_kill (/lib/x86_64-linux-gnu/libc.so.6+0x969fc)
 #5 0x00007f4dfc4c3476 gsignal (/lib/x86_64-linux-gnu/libc.so.6+0x42476)
 #6 0x00007f4dfc4a97f3 abort (/lib/x86_64-linux-gnu/libc.so.6+0x287f3)
 #7 0x00007f4dfc4a971b (/lib/x86_64-linux-gnu/libc.so.6+0x2871b)
 #8 0x00007f4dfc4bae96 (/lib/x86_64-linux-gnu/libc.so.6+0x39e96)
 #9 0x000056033b46cfa7 (anonymous namespace)::FilterChooser::emitTableEntries((anonymous namespace)::DecoderTableInfo&) const DecoderEmitter.cpp:0:0
#10 0x000056033b46ce4c (anonymous namespace)::FilterChooser::emitTableEntries((anonymous namespace)::DecoderTableInfo&) const DecoderEmitter.cpp:0:0
#11 0x000056033b468c8e (anonymous namespace)::DecoderEmitter::run(llvm::raw_ostream&) DecoderEmitter.cpp:0:0

```

</details>

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