[llvm] [SLP]Improve minbitwidth analysis for abs/smin/smax/umin/umax intrinsics. (PR #86135)

[Martin Storsjö via llvm-commits]

mstorsjo wrote:

This change broke a couple of tests in the libyuv testsuite (https://chromium.googlesource.com/libyuv/libyuv). I’ve reproduced the errors for mingw i686, x86_64 and armv7, but no errors on mingw aarch64. Also reproducible for x86_64 Linux. Build with e.g. `cmake -DCMAKE_BUILD_TYPE=Release -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ -DUNIT_TEST=ON`, might require setting up/fetching gtest manually (and passing `-DGTEST_SRC_DIR=$(pwd)/gtest/googletest` or similar), building and running `./libyuv_unittest`.

https://github.com/llvm/llvm-project/pull/86135