Merge pull request #69 from yomaytk/fix-bug

Fix the bug of strange instruction like 'bl _d_24.' by cross compilation.

backend/remill/lib/BC/TraceLifter.cpp

@@ -613,9 +613,12 @@ bool TraceLifter::Impl::Lift(uint64_t addr, const char *fn_name,
         case Instruction::kCategoryDirectFunctionCall: {
         direct_func_call:
           try_add_delay_slot(true, block);
-          if (inst.branch_not_taken_pc != inst.branch_taken_pc) {
+          auto target_trace = get_trace_decl(inst.branch_taken_pc);
+          // The ELF/aarch64 binary generated by cross compilation of clang-16 has the instruction like a `bl _d_24`.
+          // However, the symbol like `_d_24` doesn't indicate the function, so lifting it is invalid.
+          // When we find such a instruction, we treat it as `nop`.
+          if (target_trace && inst.branch_not_taken_pc != inst.branch_taken_pc) {
             trace_work_list.insert(inst.branch_taken_pc);
-            auto target_trace = get_trace_decl(inst.branch_taken_pc);
             auto lifted_func_call = AddCall(
                 block, target_trace, *intrinsics,
                 llvm::ConstantInt::get(llvm::Type::getInt64Ty(context), inst.branch_taken_pc));