[llvm-branch-commits] [llvm] Add deactivation symbol operand to ConstantPtrAuth. (PR #133537)

[Oliver Hunt via llvm-branch-commits]

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@@ -2135,6 +2135,11 @@ bool ConstantPtrAuth::hasSpecialAddressDiscriminator(uint64_t Value) const {
 bool ConstantPtrAuth::isKnownCompatibleWith(const Value *Key,
                                             const Value *Discriminator,
                                             const DataLayout &DL) const {
+  // This function may only be validly called to analyze a ptrauth operation with
+  // no deactivation symbol, so if we have one it isn't compatible.
+  if (!getDeactivationSymbol()->isNullValue())
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ojhunt wrote:

But they would be compatible if they have the _same_ deactivation symbol wouldn't they? It seems reasonable to just compare the symbol - if there's a mismatch in "present vs not present" or the relevant symbol they're compatible aren't they?

You'd just need to pass in the deactivation symbol for the other scheme?

https://github.com/llvm/llvm-project/pull/133537