public String getErrorMessage(PcodeOp op) {
		Branch branch = branches.get(op);
		return switch (branch) {
			case null -> throw new AssertionError("No branch record for op: " + op);
			case ErrBranch err -> err.message;
			default -> throw new AssertionError("Wrong branch type " + branch + " for op: " + op);
		};
	}
If the given p-code op is known to cause an error, e.g., an unimplemented instruction, get
the error message.

@param op the p-code op causing the error
@return the message for the error caused
Ghidra/Framework/Emulation/src/main/java/ghidra/pcode/emu/jit/JitPassage.java