[llvm] [clang] [PowerPC] Add an alias for -mregnames so that full register names used in assembly. (PR #70255)

[Fangrui Song via cfe-commits]

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@@ -0,0 +1,18 @@
+// REQUIRES: powerpc-registered-target
+// RUN: %clang -### -target powerpc-ibm-aix-xcoff -mcpu=pwr8 -O3 -mregnames \
+// RUN:   %s 2>&1 >/dev/null | FileCheck %s --check-prefix=FULLNAMES
+// RUN: %clang -### -target powerpc64-ibm-aix-xcoff -mcpu=pwr8 -O3 -mregnames \
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MaskRay wrote:

> This should just test that clang passes -target-feature. It's unnecessary to enumerate every combination.

I think most RUN lines can be removed. `-O3` should be removed as well.

https://github.com/llvm/llvm-project/pull/70255