[llvm-branch-commits] [clang] [clang] Define ptrauth_sign_constant builtin. (PR #93904)

[Daniil Kovalev via llvm-branch-commits]

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@@ -2061,6 +2071,58 @@ ConstantLValueEmitter::VisitCallExpr(const CallExpr *E) {
   }
 }
 
+ConstantLValue
+ConstantLValueEmitter::emitPointerAuthSignConstant(const CallExpr *E) {
+  llvm::Constant *UnsignedPointer = emitPointerAuthPointer(E->getArg(0));
+  unsigned Key = emitPointerAuthKey(E->getArg(1));
+  llvm::Constant *StorageAddress;
+  llvm::Constant *OtherDiscriminator;
+  std::tie(StorageAddress, OtherDiscriminator) =
+      emitPointerAuthDiscriminator(E->getArg(2));
+
+  llvm::Constant *SignedPointer = CGM.getConstantSignedPointer(
+      UnsignedPointer, Key, StorageAddress, OtherDiscriminator);
+  return SignedPointer;
+}
+
+llvm::Constant *ConstantLValueEmitter::emitPointerAuthPointer(const Expr *E) {
+  Expr::EvalResult Result;
+  bool Succeeded = E->EvaluateAsRValue(Result, CGM.getContext());
+  assert(Succeeded);
+  (void)Succeeded;
+
+  // The assertions here are all checked by Sema.
+  assert(Result.Val.isLValue());
+  return ConstantEmitter(CGM, Emitter.CGF)
+      .emitAbstract(E->getExprLoc(), Result.Val, E->getType());
+}
+
+unsigned ConstantLValueEmitter::emitPointerAuthKey(const Expr *E) {
+  return E->EvaluateKnownConstInt(CGM.getContext()).getZExtValue();
+}
+
+std::pair<llvm::Constant *, llvm::Constant *>
+ConstantLValueEmitter::emitPointerAuthDiscriminator(const Expr *E) {
+  E = E->IgnoreParens();
+
+  if (auto *Call = dyn_cast<CallExpr>(E)) {
+    if (Call->getBuiltinCallee() ==
+        Builtin::BI__builtin_ptrauth_blend_discriminator) {
+      llvm::Constant *Pointer = ConstantEmitter(CGM).emitAbstract(
+          Call->getArg(0), Call->getArg(0)->getType());
+      llvm::Constant *Extra = ConstantEmitter(CGM).emitAbstract(
+          Call->getArg(1), Call->getArg(1)->getType());
+      return {Pointer, Extra};
+    }
+  }
+
+  llvm::Constant *Result = ConstantEmitter(CGM).emitAbstract(E, E->getType());
+  if (Result->getType()->isPointerTy())
+    return {Result, nullptr};
+  else
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kovdan01 wrote:

Do not use else after return

https://github.com/llvm/llvm-project/pull/93904