[llvm] [PowerPC] Extend and update the test for `half` support (NFC) (PR #152625)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,2562 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=powerpc-unknown-unknown \
+; RUN:   -verify-machineinstrs -ppc-asm-full-reg-names < %s | FileCheck %s \
+; RUN:   --check-prefix=PPC32
+; RUN: llc -mcpu=pwr8 -mtriple=powerpc64le-unknown-unknown \
+; RUN:   -verify-machineinstrs -ppc-asm-full-reg-names < %s | FileCheck %s \
+; RUN:   --check-prefix=P8
+; RUN: llc -mcpu=pwr9 -mtriple=powerpc64le-unknown-unknown \
+; RUN:   -verify-machineinstrs -ppc-asm-full-reg-names < %s | FileCheck %s
----------------
nikic wrote:

```suggestion
; RUN:   --check-prefixes=CHECK,P8
; RUN: llc -mcpu=pwr9 -mtriple=powerpc64le-unknown-unknown \
; RUN:   -verify-machineinstrs -ppc-asm-full-reg-names < %s | FileCheck %s
; RUN:   --check-prefixes=CHECK,P9
```
Would something like this reduce some check lines?

https://github.com/llvm/llvm-project/pull/152625