[llvm] [flang] [clang] [AArch64][Driver] Better handling of target feature dependencies (PR #78270)

[Tomas Matheson via cfe-commits]

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@@ -1,9 +1,9 @@
 // RUN: %clang -### --target=aarch64-none-elf -march=armv8.4a+memtag %s 2>&1 | FileCheck %s
 // RUN: %clang -### --target=aarch64-none-elf -march=armv8.5a+memtag %s 2>&1 | FileCheck %s
+// RUN: %clang -### --target=aarch64-none-elf -mcpu=cortex-a510 %s 2>&1 | FileCheck %s
 // CHECK: "-target-feature" "+mte"
 
-// RUN: %clang -### --target=aarch64-none-elf -march=armv8.4a+nomemtag %s 2>&1 | FileCheck %s --check-prefix=NOMTE
-// RUN: %clang -### --target=aarch64-none-elf -march=armv8.5a+nomemtag %s 2>&1 | FileCheck %s --check-prefix=NOMTE
+// RUN: %clang -### --target=aarch64-none-elf -mcpu=cortex-a510+nomemtag %s 2>&1 | FileCheck %s --check-prefix=NOMTE
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tmatheson-arm wrote:

This seems like a material change to what is being tested, it might be better split out. (Applies to several files where `-march` has been substituted with `-mcpu`)

https://github.com/llvm/llvm-project/pull/78270