[llvm] [llvm-exegesis][AArch64] Disable pauth and ldgm as unsupported instructions (PR #132346)

[Aiden Grossman via llvm-commits]

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@@ -9,12 +9,58 @@
 #include "AArch64.h"
 #include "AArch64RegisterInfo.h"
 
+#ifdef __linux__
+#include <linux/prctl.h> // For PR_PAC_* constants
+#include <sys/prctl.h>
+#endif
+
 #define GET_AVAILABLE_OPCODE_CHECKER
 #include "AArch64GenInstrInfo.inc"
 
 namespace llvm {
 namespace exegesis {
 
+bool isPointerAuth(unsigned Opcode) {
+  switch (Opcode) {
+  default:
+    return false;
+
+  // FIXME: Pointer Authentication instructions.
+  // We would like to measure these instructions, but they can behave
+  // differently on different platforms, and maybe the snippets need to look
+  // different for these instructions,
+  // Platform-specific handling:  On Linux, we disable authentication, may
+  // interfere with measurements. On non-Linux platforms, disable opcodes for
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boomanaiden154 wrote:

Just a note: Exegesis doesn't really support benchmarking on non-Linux platforms.

https://github.com/llvm/llvm-project/pull/132346