[llvm] [llvm-readobj][AArch64][ELF][PAC] Support ELF AUTH constants (PR #72713)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,98 @@
+# RUN: rm -rf %t && split-file %s %t && cd %t
+
+# RUN: llvm-mc -filetype=obj -triple=aarch64-linux-gnu abi-tag.s       -o tag.o
+# RUN: llvm-mc -filetype=obj -triple=aarch64-linux-gnu abi-tag-short.s -o tag-short.o
+# RUN: llvm-mc -filetype=obj -triple=aarch64-linux-gnu abi-tag-long.s  -o tag-long.o
+
+# RUN: llvm-readelf --notes tag.o       | FileCheck --check-prefix NORMAL %s
+# RUN: llvm-readelf --notes tag-short.o | FileCheck --check-prefix SHORT  %s
+# RUN: llvm-readelf --notes tag-long.o  | FileCheck --check-prefix LONG   %s
+
+# NORMAL: AArch64 PAuth ABI tag: platform 0x2a, version 0x1
+# SHORT:  AArch64 PAuth ABI tag: <corrupted size: expected at least 16, got 12>
+# LONG:   AArch64 PAuth ABI tag: platform 0x2a, version 0x1, additional info 0xEFCDAB8967452301
+
+# RUN: llvm-readobj --notes tag.o       | FileCheck --check-prefix LLVM-NORMAL %s
+# RUN: llvm-readobj --notes tag-short.o | FileCheck --check-prefix LLVM-SHORT %s
+# RUN: llvm-readobj --notes tag-long.o  | FileCheck --check-prefix LLVM-LONG %s
+
+// LLVM-SHORT:      Notes [
----------------
MaskRay wrote:

We should not mix `#` and `//`. Just use `#` everywhere

https://github.com/llvm/llvm-project/pull/72713