[Lldb-commits] [lldb] [lldb] Support PtrAuth in the expression evaluator (PR #186001)

[David Spickett via lldb-commits]

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@@ -0,0 +1,29 @@
+import lldb
+from lldbsuite.test.decorators import *
+from lldbsuite.test.lldbtest import *
+from lldbsuite.test import lldbutil
+
+
+class TestPtrAuthFixups(TestBase):
+    @skipUnlessDarwin
+    @skipUnlessArch("arm64")
+    def test_static_function_pointer(self):
+        """Test that a static function pointer initialized in an expression
+        gets correctly signed on arm64e via the pointer signing fixup pass."""
+        self.build()
+
+        lldbutil.run_to_source_breakpoint(
+            self, "// break here", lldb.SBFileSpec("main.c", False)
+        )
+
+        self.expect_expr(
+            "static int (*fp)(int, int) = &add; fp(5, 6);",
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DavidSpickett wrote:

Please add a comment here to explain why this must be signed.

My understanding so far is that `fp` ends up signed, I'm not sure why it **has** to be though. I know arm64e does sign a lot of things but I don't know what enforces that I cannot just call the function at its normal, unsigned, address.

https://github.com/llvm/llvm-project/pull/186001