[llvm] [BOLT][AArch64] Allow binary-analysis and heatmap tool to run with pac-ret binaries (PR #136664)

[Anatoly Trosinenko via llvm-commits]

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@@ -2760,13 +2762,19 @@ struct CFISnapshot {
     }
     case MCCFIInstruction::OpAdjustCfaOffset:
     case MCCFIInstruction::OpWindowSave:
-    case MCCFIInstruction::OpNegateRAState:
     case MCCFIInstruction::OpNegateRAStateWithPC:
     case MCCFIInstruction::OpLLVMDefAspaceCfa:
     case MCCFIInstruction::OpLabel:
     case MCCFIInstruction::OpValOffset:
       llvm_unreachable("unsupported CFI opcode");
       break;
+    case MCCFIInstruction::OpNegateRAState:
+      if (!(opts::BinaryAnalysisMode || opts::HeatmapMode)) {
+        llvm_unreachable("BOLT-ERROR: binaries using pac-ret hardening (e.g. "
+                         "as produced by '-mbranch-protection=pac-ret') are "
+                         "currently not supported by BOLT\n");
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atrosinenko wrote:

[nit] `llvm_unreachable` doesn't need `\n` at the end of the message, I guess. The same applies to the below calls to `llvm_unreachable`.

https://github.com/llvm/llvm-project/pull/136664