DPI import function not found


I created a cpp file named get_reg_name.cpp as shown below.

extern "C" {

uint32 get_reg_addr_dpi(const char* reg_name) {
    uint32 reg_addr;
    return reg_addr;

and in my global file (my_globals.svh) I import it as shown below.

import "DPI-C" function uint32 get_reg_addr_dpi(string reg_name);

when I use it, I hit the error that the DPI import function not found. No idea what code I missed ?

Thank you !

In reply to zz8318:

Please change:

  • “uint32” in SV to “int unsigned”. SV doesn’t understand “uint32” type.
  • “uint32” in C to “unsigned int” (or keep it if you have this type in C)

I create an example for you, it works:

In reply to zz8318:

Please check the user manual of your tool for running DPI code. This forum is not for tool specific issues.

In reply to chris_le:

forget to mentioned that I already typedef it in the my_globals.svh file

typedef int unsigned uint32;

In reply to dave_59:

I have a further question that whether the import/export function declaration must be inside a module ? The error information is shown below.

Error-[DPI-DXFNF] DPI export function not found
Please check the called DPI export function/task is defined in the mentioned
module, or check if the DPI declaration of the DPI import function/task
which invokes that DPI export function/task is made with ‘context’. Another
work-around is using svGetScopeFromName/svSetScope to explicitly set the
scope to the module which contains the definition of the DPI export

In reply to zz8318:

DPI imports/exports do not need to be in a module.

Did you follow all the advice given by the error message? Did you package import the DPI exported function into the module where you called the DPI imported function?

A complete skeletal example that reproduces the problem would really help.

In reply to dave_59:

Hi Dave,
Do you mean the DPI imports/exports function needs to be inside a module, right ?
I am sorry the example I currently have is a bit complicated and I have little idea how to express it here…

In reply to zz8318:

DPI imports/exports do not need to be in a module.

I cannot help you any further without some idea of where you are declaring the DPI in/exports, and where you are calling them from.

In reply to dave_59:

I see. Thanks a lot anyway. I will try to figure it out myself. :)

In reply to dave_59:

Now I fixed the “DPI not found” issue but encountered next error which is Segmentation Fault.
May I know how to debug this kind of error ? It looks like too little error information in the logfile.

Here is my code:
C file:
struct reg_t {
unsigned int addr;
unsigned int data;

extern “C” void exported_sv_function(reg_t a);
extern “C” void get_all_reg() {
reg_t tmp;
unsigned int total = 500;
unsigned int idx;
for (idx = 0; idx < total; idx++) {
tmp.addr = idx;
tmp.data = idx;

and in my sv file :

typedef struct {
  logic [31:0] addr;
  logic [31:0] data;
} reg_t;
reg_t my_reg_array[$];

export"DPI-C" function exported_sv_function;
function void exported_sv_function(input reg_t x);

import "DPI-C" context function void get_all_reg();

and in my test (my_test.sv file)

task my_test::run_phase(uvm_phase phase);
    get_all_reg();         // The Segmentation fault is happened here

And the whole error information is shown below.

An unexpected termination has occurred in /proj/out/…/sim/exec/vcs_sim_exe due to a signal: Segmentation fault

Dumping VCS Annotated Stack:
#0 0x00000033dda0b63c in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1 0x00002aaad1154240 in ndpBIMT_popElem () from /tool/cbar/apps/verdi/2017.03-SP2-11/share/PLI/lib/LINUXAMD64/libsscore_vcs201703.so
#2 0x00002aaad115482e in ndpBIMT_ConsumerMain () from /tool/cbar/apps/verdi/2017.03-SP2-11/share/PLI/lib/LINUXAMD64/libsscore_vcs201703.so
#3 0x00000033dda07a51 in start_thread () from /lib64/libpthread.so.0
#4 0x00000033dd2e896d in clone () from /lib64/libc.so.6
#0 0x00000033dd2ac6cd in waitpid () from /lib64/libc.so.6
#1 0x00000033dd23e609 in do_system () from /lib64/libc.so.6
#2 0x00000033dd23e940 in system () from /lib64/libc.so.6
#3 0x00002aaab41f71bb in SNPSle_10ee25eff68cd8461c9146fa1d0b35e87067f3c8015b313e639d2928478c79b3f673f99203bcf8be64600612100082236bffb2007f1e0ef9 () from /tool/cbar/apps/vcs-mx/2017.03-SP2-11/linux64/lib/liberrorinf.so
#4 0x00002aaab41f8bc6 in SNPSle_10ee25eff68cd8461c9146fa1d0b35e87067f3c8015b313efba706aab251478fa49e66610e453774633a6c152e7ef778f2202cda681f3d4e () from /tool/cbar/apps/vcs-mx/2017.03-SP2-11/linux64/lib/liberrorinf.so
#5 0x00002aaab41f1c95 in SNPSle_d35ca1ff70d465c2b9b1a72eee90a506fdd009d3de3db1de () from /tool/cbar/apps/vcs-mx/2017.03-SP2-11/linux64/lib/liberrorinf.so
#6 0x00002aaab733ce68 in SNPSle_64133461705005bb725549e2e6fa1b3f () from /tool/cbar/apps/vcs-mx/2017.03-SP2-11/linux64/lib/libvcsnew.so
#7 0x00002aaab719e43e in SNPSle_82244d58c54c18c70d63edc9becab634 () from /tool/cbar/apps/vcs-mx/2017.03-SP2-11/linux64/lib/libvcsnew.so
#9 0x00000033dd283900 in memmove () from /lib64/libc.so.6
#10 0x00002aaab84715c4 in SNPSle_2681ff91466c07ba85e55d8e718f74c7f0dd524361188f7def6afc2d54b39315 () from /tool/cbar/apps/vcs-mx/2017.03-SP2-11/linux64/lib/libvcsnew.so
#11 0x00002aaab847442f in SNPSle_64cf966be35473e7c27d42cab9451f7c620b2a08eac4939b () from /tool/cbar/apps/vcs-mx/2017.03-SP2-11/linux64/lib/libvcsnew.so
#12 0x00002aaaac929ba9 in F_VCSgd_EaWgM_166_0 () from /proj/…/pub/sim/exec/vcs_sim_exe.daidir/_29753_archive_1.so
#13 0x00002aaaaf36b5b2 in exported_sv_function () from /proj/…/pub/sim/exec/vcs_sim_exe.daidir/_prev_archive_1.so
#14 0x0000000000427655 in rlc_get_all_reg ()
#15 0x00002aaaac913059 in U_VCSgd_EaWgM_136 () from /proj/…/pub/sim/exec/vcs_sim_exe.daidir/_29753_archive_1.so
#16 0x00002aaab73ba864 in SNPSle_ba9d6ef1a21efcfe () from /tool/cbar/apps/vcs-mx/2017.03-SP2-11/linux64/lib/libvcsnew.so
#17 0x00002aaaac8fc15f in U_VCSgd_EaWgM_16 () from /proj/…/pub/sim/exec/vcs_sim_exe.daidir/_29753_archive_1.so
#18 0x00002aaab73ba864 in SNPSle_ba9d6ef1a21efcfe () from /tool/cbar/apps/vcs-mx/2017.03-SP2-11/linux64/lib/libvcsnew.so
#19 0x00002aaab73ba864 in SNPSle_ba9d6ef1a21efcfe () from /tool/cbar/apps/vcs-mx/2017.03-SP2-11/linux64/lib/libvcsnew.so
#20 0x00002aaab73ba864 in SNPSle_ba9d6ef1a21efcfe () from /tool/cbar/apps/vcs-mx/2017.03-SP2-11/linux64/lib/libvcsnew.so
#21 0x00002aaaafb7e629 in U_VCSgd_hEeZs_211 () from /proj/…/pub/sim/exec/vcs_sim_exe.daidir/_prev_archive_1.so
#22 0x00002aaaafb7f11d in F_VCSgd_hEeZs_13328_0 () from /proj/…/pub/sim/exec/vcs_sim_exe.daidir/_prev_archive_1.so
#23 0x00002aaaafb7e97a in U_VCSgd_hEeZs_212 () from /proj/…/pub/sim/exec/vcs_sim_exe.daidir/_prev_archive_1.so
#24 0x00002aaaaf634f83 in N_VCSgd_irqrb () from /proj/…/pub/sim/exec/vcs_sim_exe.daidir/_prev_archive_1.so
#25 0x00002aaab72ed620 in SNPSle_63c7abb936d47b07d29d61775f9dbe8c () from /tool/cbar/apps/vcs-mx/2017.03-SP2-11/linux64/lib/libvcsnew.so
#26 0x00002aaab7351f2f in SNPSle_490598bfebcc8e81efcf3d1815066cc9 () from /tool/cbar/apps/vcs-mx/2017.03-SP2-11/linux64/lib/libvcsnew.so
#27 0x00002aaab7367178 in SNPSle_490598bfebcc8e81 () from /tool/cbar/apps/vcs-mx/2017.03-SP2-11/linux64/lib/libvcsnew.so
#28 0x00002aaab3814717 in main () from /proj/…/pub/sim/exec/vcs_sim_exe.daidir/_csrc0.so
#29 0x00000033dd21ed5d in __libc_start_main () from /lib64/libc.so.6
#30 0x0000000000426289 in _start ()

Thanks for your great help in advance.

In reply to zz8318:

Debugging DPI code requires tool specific help, and this Mentor sponsored public forum is not for tool specific issues. Please contact your vendor directly.

In reply to zz8318:

As a follow-up to Dave’s comment, you should read Appendix H of the LRM regarding the DPI C layer and how data types are mapped. A logic[31:0] is not compatible with unsigned int.

In reply to cgales:

I tried other type actually but met the same issue.

In reply to zz8318:

Hi, How did you rsolve the DPI not found error. I am facing the same issue after folllowing all steps diligently