[llvm] [AArch64] Refactor @plt, @gotpcrel, and @AUTH to use parseDataExpr (PR #134202)

[Peter Smith via llvm-commits]

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@@ -32,13 +33,21 @@ data1:
 .word extern at GOTPCREL-5
 
 .ifdef ERR
-# ERR: [[#@LINE+1]]:7: error: symbol 'und' can not be undefined in a subtraction expression
-.word extern at plt - und
+# ERR: [[#@LINE+1]]:9: error: @ specifier only allowed after a symbol
+.quad 3 at plt - .
+
+# ERR: [[#@LINE+1]]:9: error: expected ')'
+.quad (l at plt - .)
+.endif
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smithp35 wrote:

Github's UI makes the `l` look very similar to a `1`. Likely not a problem in plain text, but it looks a bit strange when reviewing after `3 at plt`.

https://github.com/llvm/llvm-project/pull/134202