ASSERT (opnd_create_immed_int: value too large for 8-bit size) in offline tracer when running with L0_filter and if application has basic block longer than 256 insts

Describe the bug The assert occurs if we have a basic block longer than 256 instructions. The assert goes away if I change OPND_CREATE_INT8(ud->bb_instr_count))); to OPND_CREATE_INT16(ud->bb_instr_count)));

   1051        if (op_L0_filter.get_value()) {
   1052            // Count dynamic instructions per thread.
   1053            // It is too expensive to increment per instruction, so we increment once
   1054            // per block by the instruction count for that block.
   1055            if (drmgr_is_first_nonlabel_instr(drcontext, app)) {
   1056                // On x86 we could do this in one instruction if we clobber the flags: but
   1057                // then we'd have to preserve the flags before our same-line skip in
   1058                // insert_filter_addr().
   1059                dr_insert_read_raw_tls(drcontext, ilist, where, tls_seg,
   1060                                       tls_offs + sizeof(void *) * MEMTRACE_TLS_OFFS_ICOUNT,
   1061                                       reg_ptr);
   1062                MINSERT(ilist, where,
  >1063                        XINST_CREATE_add(drcontext, opnd_create_reg(reg_ptr),
   1064                                         OPND_CREATE_INT8(ud->bb_instr_count)));
   1065                dr_insert_write_raw_tls(drcontext, ilist, where, tls_seg,
   1066                                        tls_offs + sizeof(void *) * MEMTRACE_TLS_OFFS_ICOUNT,
   1067                                        reg_ptr);
   1068            }

(gdb) p ud->bb_instr_count
$5 = 257

To Reproduce Run offline tracer with the L0_filter option and an application that has a basic block longer than 256 instructions.

drrun -t drcachesim -offline -L0_filter -- <app>

Expected behavior The assert should not fail.

Screenshots or Pasted Text

opnd_create_immed_int: value too large for 8-bit size

Versions

• What version of DynamoRIO are you using? cronbuild-8.0.18752
• Does the latest build from https://github.com/DynamoRIO/dynamorio/releases solve the problem? No
• What operating system version are you running on? Ubuntu 18.04.5 LTS
• Is your application 32-bit or 64-bit? ELF 64-bit LSB executable

Additional context None