[llvm] [PAC][IR][AArch64] Add "ptrauth(...)" Constant to represent signed pointers. (PR #85738)

[Ahmed Bougacha via llvm-commits]

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@@ -2015,6 +2018,118 @@ Value *NoCFIValue::handleOperandChangeImpl(Value *From, Value *To) {
   return nullptr;
 }
 
+//---- ConstantPtrAuth::get() implementations.
+//
+
+static bool areEquivalentAddrDiscriminators(const Value *V1, const Value *V2,
+                                            const DataLayout &DL) {
+  APInt V1Off(DL.getPointerSizeInBits(), 0);
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ahmedbougacha wrote:

Went with type size to allow the (somewhat unfortunate) cases of blend intrinsics taking i64, but the constant having pointers.  I could probably rejigger the whole body to have them consistently on a single index type

https://github.com/llvm/llvm-project/pull/85738