release/21.x: [clang][PAC] Fix PAC codegen for final class dynamic_cast optimization (#152227)

[llvmbot]

Backport 7268478

Requested by: @ojhunt

[llvmbot]

@asl What do you think about merging this PR to the release branch?

[llvmbot]

@llvm/pr-subscribers-clang-codegen

@llvm/pr-subscribers-clang

Author: None (llvmbot)

Changes

Backport 7268478

Requested by: @ojhunt

---

Full diff: https://github.com/llvm/llvm-project/pull/152587.diff

2 Files Affected:

• (modified) clang/lib/CodeGen/CGExprCXX.cpp (+2-1)
• (modified) clang/test/CodeGenCXX/dynamic-cast-exact-disabled.cpp (+1)

diff --git a/clang/lib/CodeGen/CGExprCXX.cpp b/clang/lib/CodeGen/CGExprCXX.cpp
index 359e30cb8f5cd..912b1d72c7e23 100644
--- a/clang/lib/CodeGen/CGExprCXX.cpp
+++ b/clang/lib/CodeGen/CGExprCXX.cpp
@@ -2313,7 +2313,8 @@ llvm::Value *CodeGenFunction::EmitDynamicCast(Address ThisAddr,
   bool IsExact = !IsDynamicCastToVoid &&
                  CGM.getCodeGenOpts().OptimizationLevel > 0 &&
                  DestRecordTy->getAsCXXRecordDecl()->isEffectivelyFinal() &&
-                 CGM.getCXXABI().shouldEmitExactDynamicCast(DestRecordTy);
+                 CGM.getCXXABI().shouldEmitExactDynamicCast(DestRecordTy) &&
+                 !getLangOpts().PointerAuthCalls;
 
   // C++ [expr.dynamic.cast]p4:
   //   If the value of v is a null pointer value in the pointer case, the result
diff --git a/clang/test/CodeGenCXX/dynamic-cast-exact-disabled.cpp b/clang/test/CodeGenCXX/dynamic-cast-exact-disabled.cpp
index 9a8ce1997a7f9..19c2a9bd0497e 100644
--- a/clang/test/CodeGenCXX/dynamic-cast-exact-disabled.cpp
+++ b/clang/test/CodeGenCXX/dynamic-cast-exact-disabled.cpp
@@ -3,6 +3,7 @@
 // RUN: %clang_cc1 -I%S %s -triple x86_64-apple-darwin10 -O1 -fvisibility=hidden -emit-llvm -std=c++11 -o - | FileCheck %s --check-prefixes=CHECK,INEXACT
 // RUN: %clang_cc1 -I%S %s -triple x86_64-apple-darwin10 -O1 -fapple-kext -emit-llvm -std=c++11 -o - | FileCheck %s --check-prefixes=CHECK,INEXACT
 // RUN: %clang_cc1 -I%S %s -triple x86_64-apple-darwin10 -O1 -fno-assume-unique-vtables -emit-llvm -std=c++11 -o - | FileCheck %s --check-prefixes=CHECK,INEXACT
+// RUN: %clang_cc1 -I%S %s -triple arm64e-apple-darwin10 -O1 -fptrauth-calls -emit-llvm -std=c++11 -o - | FileCheck %s --check-prefixes=CHECK,INEXACT
 
 struct A { virtual ~A(); };
 struct B final : A { };

[tru]

There was two PR's with the same changes. I just closed this one because of that. Let me know if that was wrong.

[ojhunt]

@tru this was me misunderstanding the back porting automation sorry :D