[llvm] [X86] combineINSERT_SUBVECTOR - fold insert_subvector(base,extract_subvector(broadcast)) -> blend shuffle(base,broadcast) (PR #133083)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-ppc64-aix` running on `aix-ppc64` while building `llvm` at step 5 "build-unified-tree".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/64/builds/2635

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

```
Step 5 (build-unified-tree) failure: build (failure)
2.962 [134/3/1] Generating VCSRevision.h
3.097 [65/3/2] Generating VCSVersion.inc
7.507 [50/2/3] Building CXX object tools/llvm-config/CMakeFiles/llvm-config.dir/llvm-config.cpp.o
7.709 [49/2/4] Linking CXX executable bin/llvm-config
28.166 [49/1/5] Building CXX object lib/Target/X86/CMakeFiles/LLVMX86CodeGen.dir/X86ISelLowering.cpp.o
FAILED: lib/Target/X86/CMakeFiles/LLVMX86CodeGen.dir/X86ISelLowering.cpp.o 
/home/llvm/llvm-external-buildbots/clang.19.1.2/bin/clang++ -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_LARGE_FILE_API -D_XOPEN_SOURCE=700 -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/llvm/llvm-external-buildbots/workers/aix-ppc64/clang-ppc64-aix/build/lib/Target/X86 -I/home/llvm/llvm-external-buildbots/workers/aix-ppc64/clang-ppc64-aix/llvm-project/llvm/lib/Target/X86 -I/home/llvm/llvm-external-buildbots/workers/aix-ppc64/clang-ppc64-aix/build/include -I/home/llvm/llvm-external-buildbots/workers/aix-ppc64/clang-ppc64-aix/llvm-project/llvm/include -mcmodel=large -fPIC -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 -pthread -MD -MT lib/Target/X86/CMakeFiles/LLVMX86CodeGen.dir/X86ISelLowering.cpp.o -MF lib/Target/X86/CMakeFiles/LLVMX86CodeGen.dir/X86ISelLowering.cpp.o.d -o lib/Target/X86/CMakeFiles/LLVMX86CodeGen.dir/X86ISelLowering.cpp.o -c /home/llvm/llvm-external-buildbots/workers/aix-ppc64/clang-ppc64-aix/llvm-project/llvm/lib/Target/X86/X86ISelLowering.cpp
/home/llvm/llvm-external-buildbots/workers/aix-ppc64/clang-ppc64-aix/llvm-project/llvm/lib/Target/X86/X86ISelLowering.cpp:58962:14: error: comparison of integers of different signs: 'uint64_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]
 58962 |   if (IdxVal == (VecNumElts / 2) &&
       |       ~~~~~~ ^   ~~~~~~~~~~~~~~
1 error generated.
ninja: build stopped: subcommand failed.

```

</details>

https://github.com/llvm/llvm-project/pull/133083