[llvm] [clang] Enable descriptions for --print-supported-extensions (PR #66715)

[David Spickett via llvm-commits]

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@@ -4,14 +4,17 @@
 // RUN: %if aarch64-registered-target %{ %clang --target=aarch64-linux-gnu \
 // RUN:   --print-supported-extensions 2>&1 | FileCheck %s --check-prefix AARCH64 %}
 // AARCH64: All available -march extensions for AArch64
+// AARCH64:     Name                Description
 
 // RUN: %if riscv-registered-target %{ %clang --target=riscv64-linux-gnu \
 // RUN:   --print-supported-extensions 2>&1 | FileCheck %s --check-prefix RISCV %}
 // RISCV: All available -march extensions for RISC-V
+// RISCV:     Name                Version   Description
 
 // RUN: %if arm-registered-target %{ %clang --target=arm-linux-gnu \
 // RUN:   --print-supported-extensions 2>&1 | FileCheck %s --check-prefix ARM %}
 // ARM: All available -march extensions for ARM
+// ARM:     Name                Description
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DavidSpickett wrote:

It is, and that's great, but, if someone decides to refactor this one day and suddenly they aren't using those functions anymore, we could miss it. It's unlikely but it's cheap to add a few lines here as well to cover that possibility.

Also, it's far easier for someone who is trying to understand the option to read this test file than it is to know that it calls 3 different methods in the background. So from a documentation point of view it also helps.

https://github.com/llvm/llvm-project/pull/66715