release/19.x: [clang] Implement -fptrauth-auth-traps. (#102417)

[llvmbot]

Backport d179acd

Requested by: @asl

[llvmbot]

@kovdan01 What do you think about merging this PR to the release branch?

[llvmbot]

@llvm/pr-subscribers-clang

@llvm/pr-subscribers-clang-codegen

Author: None (llvmbot)

Changes

Backport d179acd

Requested by: @asl

---

Full diff: https://github.com/llvm/llvm-project/pull/102938.diff

4 Files Affected:

• (modified) clang/include/clang/Basic/PointerAuthOptions.h (+3)
• (modified) clang/lib/CodeGen/CodeGenFunction.cpp (+2)
• (modified) clang/lib/Frontend/CompilerInvocation.cpp (+4-3)
• (modified) clang/test/CodeGen/ptrauth-function-attributes.c (+5)

diff --git a/clang/include/clang/Basic/PointerAuthOptions.h b/clang/include/clang/Basic/PointerAuthOptions.h
index c0ab35bce5d84b..a26af69e1fa246 100644
--- a/clang/include/clang/Basic/PointerAuthOptions.h
+++ b/clang/include/clang/Basic/PointerAuthOptions.h
@@ -162,6 +162,9 @@ struct PointerAuthOptions {
   /// Should return addresses be authenticated?
   bool ReturnAddresses = false;
 
+  /// Do authentication failures cause a trap?
+  bool AuthTraps = false;
+
   /// Do indirect goto label addresses need to be authenticated?
   bool IndirectGotos = false;
 
diff --git a/clang/lib/CodeGen/CodeGenFunction.cpp b/clang/lib/CodeGen/CodeGenFunction.cpp
index 4dc57d0ff5b269..2b2e23f1e5d7fb 100644
--- a/clang/lib/CodeGen/CodeGenFunction.cpp
+++ b/clang/lib/CodeGen/CodeGenFunction.cpp
@@ -884,6 +884,8 @@ void CodeGenFunction::StartFunction(GlobalDecl GD, QualType RetTy,
     Fn->addFnAttr("ptrauth-returns");
   if (CodeGenOpts.PointerAuth.FunctionPointers)
     Fn->addFnAttr("ptrauth-calls");
+  if (CodeGenOpts.PointerAuth.AuthTraps)
+    Fn->addFnAttr("ptrauth-auth-traps");
   if (CodeGenOpts.PointerAuth.IndirectGotos)
     Fn->addFnAttr("ptrauth-indirect-gotos");
 
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index fa5d076c202a36..028fdb2cc6b9da 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -1504,16 +1504,17 @@ void CompilerInvocation::setDefaultPointerAuthOptions(
     Opts.CXXMemberFunctionPointers =
         PointerAuthSchema(Key::ASIA, false, Discrimination::Type);
   }
-  Opts.IndirectGotos = LangOpts.PointerAuthIndirectGotos;
   Opts.ReturnAddresses = LangOpts.PointerAuthReturns;
+  Opts.AuthTraps = LangOpts.PointerAuthAuthTraps;
+  Opts.IndirectGotos = LangOpts.PointerAuthIndirectGotos;
 }
 
 static void parsePointerAuthOptions(PointerAuthOptions &Opts,
                                     const LangOptions &LangOpts,
                                     const llvm::Triple &Triple,
                                     DiagnosticsEngine &Diags) {
-  if (!LangOpts.PointerAuthCalls && !LangOpts.PointerAuthIndirectGotos &&
-      !LangOpts.PointerAuthReturns)
+  if (!LangOpts.PointerAuthCalls && !LangOpts.PointerAuthReturns &&
+      !LangOpts.PointerAuthAuthTraps && !LangOpts.PointerAuthIndirectGotos)
     return;
 
   CompilerInvocation::setDefaultPointerAuthOptions(Opts, LangOpts, Triple);
diff --git a/clang/test/CodeGen/ptrauth-function-attributes.c b/clang/test/CodeGen/ptrauth-function-attributes.c
index 17ebf9d6e2e01c..e7081f00b4f686 100644
--- a/clang/test/CodeGen/ptrauth-function-attributes.c
+++ b/clang/test/CodeGen/ptrauth-function-attributes.c
@@ -8,6 +8,9 @@
 // RUN: %clang_cc1 -triple arm64-apple-ios   -fptrauth-returns -emit-llvm %s -o - | FileCheck %s --check-prefixes=ALL,RETS
 // RUN: %clang_cc1 -triple aarch64-linux-gnu -fptrauth-returns -emit-llvm %s -o - | FileCheck %s --check-prefixes=ALL,RETS
 
+// RUN: %clang_cc1 -triple arm64-apple-ios   -fptrauth-auth-traps -emit-llvm %s -o - | FileCheck %s --check-prefixes=ALL,TRAPS
+// RUN: %clang_cc1 -triple aarch64-linux-gnu -fptrauth-auth-traps -emit-llvm %s -o - | FileCheck %s --check-prefixes=ALL,TRAPS
+
 // RUN: %clang_cc1 -triple arm64-apple-ios   -fptrauth-indirect-gotos -emit-llvm %s -o - | FileCheck %s --check-prefixes=ALL,GOTOS
 // RUN: %clang_cc1 -triple aarch64-linux-gnu -fptrauth-indirect-gotos -emit-llvm %s -o - | FileCheck %s --check-prefixes=ALL,GOTOS
 
@@ -19,6 +22,8 @@ void test() {
 
 // RETS: attributes #0 = {{{.*}} "ptrauth-returns" {{.*}}}
 
+// TRAPS: attributes #0 = {{{.*}} "ptrauth-auth-traps" {{.*}}}
+
 // GOTOS: attributes #0 = {{{.*}} "ptrauth-indirect-gotos" {{.*}}}
 
 // OFF-NOT: attributes {{.*}} "ptrauth-

[asl]

This is the second change similar to #102670

It is a small frontend change require to close the chain of changes required for end-to-end support of pointer authentication in LLVM 19.

The change does not affect any other target and essentially just propagate command line options down to attributes.

[github-actions]

@asl (or anyone else). If you would like to add a note about this fix in the release notes (completely optional). Please reply to this comment with a one or two sentence description of the fix. When you are done, please add the release:note label to this PR.