[llvm] [GlobalIsel] Add G_SCMP and G_UCMP instructions (PR #98894)

[Thorsten Schütt via llvm-commits]

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@@ -1,4 +1,5 @@
-# RUN: not --crash llc -verify-machineinstrs -run-pass none -o /dev/null %s 2>&1 | FileCheck %s
+# RUN: not --crash llc -verify-machineinstrs -mtriple=arm64 -run-pass none -o /dev/null %s 2>&1 | FileCheck %s
+# REQUIRES: aarch64-registered-target
----------------
tschuett wrote:

```
cmake -DCMAKE_BUILD_TYPE=Release -DLLVM_ENABLE_ASSERTIONS=On -DLLVM_TARGETS_TO_BUILD="AArch64;AMDGPU" -G Ninja -DLLVM_ENABLE_PROJECTS="llvm" -DLLVM_ENABLE_LTO=Thin -DCMAKE_CXX_FLAGS="-march=native" -DCMAKE_EXPORT_COMPILE_COMMANDS=On -DLLVM_ENABLE_SPHINX=ON ./llvm
```


https://github.com/llvm/llvm-project/pull/98894