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Debugging AVX-512 application with Intel SDE

borrow
Beginner
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Hello,

 

I am trying to debug AVX-512 instructions on an emulated CPU using Intel® Software Development Emulator but it doesn't work as desired after setting a breakpoint. I followed this blog post: Debugging Emulated Code on Linux* 

 

In window #1:

 

 

~$ g++ -g -O0 -mavx512f main.cpp -o main # compile main.cpp file
~$ sde -debug -- ./main

Application stopped until continued from debugger.
Start GDB, then issue this command at the (gdb) prompt:
target remote :54105

 

 

 

In window #2

 

 

~$ gdb ./main
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Type "show configuration" for configuration details.
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Reading symbols from ./main...

(gdb) target remote :54105
Remote debugging using :54105
warning: remote target does not support file transfer, attempting to access files from local filesystem.
Reading symbols from /lib64/ld-linux-x86-64.so.2...
(No debugging symbols found in /lib64/ld-linux-x86-64.so.2)
0x00007fa7bbbcc100 in ?? () from /lib64/ld-linux-x86-64.so.2

(gdb) break main
Breakpoint 1 at 0x2c9c: file /home/developer/source/repos/se-test/main.cpp, line 165.

(gdb) c
Continuing.
warning: Probes-based dynamic linker interface failed.
Reverting to original interface.
[Inferior 1 (Remote target) exited normally]

 

 

 

It should run the program until the breakpoint but gives me a warning message:

 

 

warning: Probes-based dynamic linker interface failed.

 

 

 
In window #1: The program runs and ends (without stopping). How can I solve this problem?
 
 Program code looks like this:
 
//  main.cpp
float a[256] = {0};
float b[256] = {0};
float c[256] = {0};


void foo()
{
       __m512 result,B,C;
       for (int i=0; i<256; i+=16)
      {
           B = _mm512_load_ps(&b[i]);
           C = _mm512_load_ps(&c[i]);
           result = _mm512_add_ps(B,C);
           _mm512_store_ps(&a[i], result);
       }
}
 
int main() {
     ...
     foo();
     ...
}
 
 
I tried running AVX2 code without SDE emulator using gdb and it worked. First I start it on an emulated CPU with SDE, it fails.
 
 
 
 
 
 
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AdyT_Intel
Moderator
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From the GDB output at line:

Breakpoint 1 at 0x2c9c: file /home/developer/source/repos/se-test/main.cpp, line 165.

 

It looks like the executable is PIE (position independent).
If this is the case, then it is a known problem that we plan to fix.
Until this fix is available please build the executable without PIE.

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