[clang] [ARM] Aligned mtp behavior and gcc (PR #128728)

[Simon Tatham via cfe-commits]

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@@ -42,4 +42,8 @@
 
 // RUN: %clang --target=armv7-linux -### -S %s 2>&1 | \
 // RUN: FileCheck -check-prefix=ARMv7_THREAD_POINTER_NON %s
-// ARMv7_THREAD_POINTER_NON-NOT: "-target-feature" "+read-tp-tpidruro"
+// ARMv7_THREAD_POINTER_NON: "-target-feature" "+read-tp-tpidruro"
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statham-arm wrote:

I don't understand how this test matches the change in `getARMTargetFeatures`. In that function, you respond to `-mtp=auto` by setting the feature `+read-tp-tpidrprw`. But here the test is expecting `+read-tp-tpidruro`, which isn't the same. Can you explain?

https://github.com/llvm/llvm-project/pull/128728