[llvm] [SLP] Fix the Vec lane overridden by the shuffle mask (PR #106341)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-aarch64-sve-vla` running on `linaro-g3-03` while building `llvm` at step 7 "ninja check 1".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/17/builds/2261

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

```
Step 7 (ninja check 1) failure: stage 1 checked (failure)
******************** TEST 'libFuzzer-aarch64-default-Linux :: symbolize-deadlock.test' FAILED ********************
Exit Code: 1

Command Output (stdout):
--
INFO: Running with entropic power schedule (0xFF, 100).
INFO: Seed: 1258392354
INFO: Loaded 1 modules   (10 inline 8-bit counters): 10 [0xaaaad079ee98, 0xaaaad079eea2), 
INFO: Loaded 1 PC tables (10 PCs): 10 [0xaaaad079eea8,0xaaaad079ef48), 
INFO: -max_len is not provided; libFuzzer will not generate inputs larger than 4096 bytes
INFO: A corpus is not provided, starting from an empty corpus
#2	INITED cov: 2 ft: 3 corp: 1/1b exec/s: 0 rss: 31Mb
#7	NEW    cov: 3 ft: 4 corp: 2/4b lim: 4 exec/s: 0 rss: 31Mb L: 3/3 MS: 5 ChangeBit-CrossOver-CopyPart-ChangeBinInt-InsertByte-
#3164	NEW    cov: 4 ft: 5 corp: 3/8b lim: 33 exec/s: 0 rss: 31Mb L: 4/4 MS: 2 InsertByte-ChangeByte-
#3415	REDUCE cov: 4 ft: 5 corp: 3/7b lim: 33 exec/s: 0 rss: 31Mb L: 3/3 MS: 1 EraseBytes-
#121475	REDUCE cov: 5 ft: 6 corp: 4/10b lim: 1200 exec/s: 0 rss: 40Mb L: 3/3 MS: 5 ChangeByte-ChangeByte-ChangeBinInt-CopyPart-ChangeBit-
==63424== ERROR: libFuzzer: out-of-memory (used: 59Mb; limit: 20Mb)
   To change the out-of-memory limit use -rss_limit_mb=<N>

Live Heap Allocations: 24470063 bytes in 63 chunks; quarantined: 191425 bytes in 7696 chunks; 382801 other chunks; total chunks: 390560; showing top 95% (at most 8 unique contexts)
21233984 byte(s) (86%) in 1 allocation(s)
    #0 0xaaaad073f1f0 in operator new(unsigned long) /home/tcwg-buildbot/worker/clang-aarch64-sve-vla/llvm/compiler-rt/lib/asan/asan_new_delete.cpp:86:3
    #1 0xaaaad0633c60 in fuzzer::FuzzerDriver(int*, char***, int (*)(unsigned char const*, unsigned long)) /home/tcwg-buildbot/worker/clang-aarch64-sve-vla/llvm/compiler-rt/lib/fuzzer/FuzzerDriver.cpp:815:18
    #2 0xaaaad065fd08 in main /home/tcwg-buildbot/worker/clang-aarch64-sve-vla/llvm/compiler-rt/lib/fuzzer/FuzzerMain.cpp:20:10
    #3 0xffffb8b973f8 in __libc_start_call_main csu/../sysdeps/nptl/libc_start_call_main.h:58:16
    #4 0xffffb8b974c8 in __libc_start_main csu/../csu/libc-start.c:392:3
    #5 0xaaaad06294ac in _start (/home/tcwg-buildbot/worker/clang-aarch64-sve-vla/stage1/runtimes/runtimes-bins/compiler-rt/test/fuzzer/AARCH64DefaultLinuxConfig/Output/symbolize-deadlock.test.tmp+0x394ac)

3148000 byte(s) (12%) in 1 allocation(s)
    #0 0xaaaad073f1f0 in operator new(unsigned long) /home/tcwg-buildbot/worker/clang-aarch64-sve-vla/llvm/compiler-rt/lib/asan/asan_new_delete.cpp:86:3
    #1 0xaaaad0633c44 in fuzzer::FuzzerDriver(int*, char***, int (*)(unsigned char const*, unsigned long)) /home/tcwg-buildbot/worker/clang-aarch64-sve-vla/llvm/compiler-rt/lib/fuzzer/FuzzerDriver.cpp:814:14
    #2 0xaaaad065fd08 in main /home/tcwg-buildbot/worker/clang-aarch64-sve-vla/llvm/compiler-rt/lib/fuzzer/FuzzerMain.cpp:20:10
    #3 0xffffb8b973f8 in __libc_start_call_main csu/../sysdeps/nptl/libc_start_call_main.h:58:16
    #4 0xffffb8b974c8 in __libc_start_main csu/../csu/libc-start.c:392:3
    #5 0xaaaad06294ac in _start (/home/tcwg-buildbot/worker/clang-aarch64-sve-vla/stage1/runtimes/runtimes-bins/compiler-rt/test/fuzzer/AARCH64DefaultLinuxConfig/Output/symbolize-deadlock.test.tmp+0x394ac)

MS: 5 ChangeByte-error: Aborted (core dumped)

--
Command Output (stderr):
--
RUN: at line 1: /home/tcwg-buildbot/worker/clang-aarch64-sve-vla/stage1/./bin/clang    -Wthread-safety -Wthread-safety-reference -Wthread-safety-beta   --driver-mode=g++ -O2 -gline-tables-only -fsanitize=address,fuzzer -I/home/tcwg-buildbot/worker/clang-aarch64-sve-vla/llvm/compiler-rt/lib/fuzzer  -Wthread-safety -Wthread-safety-reference -Wthread-safety-beta  /home/tcwg-buildbot/worker/clang-aarch64-sve-vla/llvm/compiler-rt/test/fuzzer/SymbolizeDeadlock.cpp -o /home/tcwg-buildbot/worker/clang-aarch64-sve-vla/stage1/runtimes/runtimes-bins/compiler-rt/test/fuzzer/AARCH64DefaultLinuxConfig/Output/symbolize-deadlock.test.tmp
+ /home/tcwg-buildbot/worker/clang-aarch64-sve-vla/stage1/./bin/clang -Wthread-safety -Wthread-safety-reference -Wthread-safety-beta --driver-mode=g++ -O2 -gline-tables-only -fsanitize=address,fuzzer -I/home/tcwg-buildbot/worker/clang-aarch64-sve-vla/llvm/compiler-rt/lib/fuzzer -Wthread-safety -Wthread-safety-reference -Wthread-safety-beta /home/tcwg-buildbot/worker/clang-aarch64-sve-vla/llvm/compiler-rt/test/fuzzer/SymbolizeDeadlock.cpp -o /home/tcwg-buildbot/worker/clang-aarch64-sve-vla/stage1/runtimes/runtimes-bins/compiler-rt/test/fuzzer/AARCH64DefaultLinuxConfig/Output/symbolize-deadlock.test.tmp
RUN: at line 2: not  /home/tcwg-buildbot/worker/clang-aarch64-sve-vla/stage1/runtimes/runtimes-bins/compiler-rt/test/fuzzer/AARCH64DefaultLinuxConfig/Output/symbolize-deadlock.test.tmp -rss_limit_mb=20 2>&1
+ not /home/tcwg-buildbot/worker/clang-aarch64-sve-vla/stage1/runtimes/runtimes-bins/compiler-rt/test/fuzzer/AARCH64DefaultLinuxConfig/Output/symbolize-deadlock.test.tmp -rss_limit_mb=20

--

********************


```

</details>

https://github.com/llvm/llvm-project/pull/106341