[llvm] [PtrAuth] Add ConstantPtrAuth comparator to FunctionComparator.cpp (PR #159480)

[Anton Korobeynikov via llvm-commits]

================
@@ -0,0 +1,67 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --include-generated-funcs --version 2
+;; Check the case for ConstantPtrAuth to be compared properly in FunctionComparator.cpp
+; RUN: opt -S -passes=mergefunc < %s | FileCheck %s
+target triple = "arm64e-apple-ios14.0.0"
+
+define { ptr, i64 } @"foo"() {
+start:
+  %func = alloca [8 x i8], align 8
+  br i1 false, label %bb5, label %bb9
+
+bb9:                                              ; preds = %bb2, %start
+  %self = load i8, ptr null, align 1
+  br i1 false, label %bb2, label %bb5
+
+bb5:                                              ; preds = %bb9, %start
+  ret { ptr, i64 } zeroinitializer
+
+bb2:                                              ; preds = %bb9
+  call void ptrauth (ptr null, i32 0)(ptr null, i8 0)
----------------
asl wrote:

I think we'd need more testcases to ensure that we e.g. do not merge things when discriminators do not match, but pointers do and similar things (e.g. do not merge address-discriminated pauth constant with the similar but w/o address discrimination)

https://github.com/llvm/llvm-project/pull/159480