[llvm] [readtapi] Use OptParser.td for options (PR #72183)

[Juergen Ributzka via llvm-commits]

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@@ -0,0 +1,7 @@
+; RUN: llvm-readtapi --help 2>&1 | FileCheck %s 
+; RUN: llvm-readtapi -help 2>&1 | FileCheck %s 
+
+CHECK: OVERVIEW: LLVM TAPI file reader and manipulator
+CHECK: USAGE: llvm-readtapi [options] <inputs>
+CHECK: OPTIONS:
+CHECK:   -help    display this help
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ributzka wrote:

Does it also emit help for the compare option?

https://github.com/llvm/llvm-project/pull/72183