We try to debug on Xeon Phi the code which contains the following code construction:
[cpp]
#include <iostream>
#include <memory.h>
#include <immintrin.h>
using namespace std;
void f( float* _amatr)
{
__m512 a;
a = _mm512_load_ps(_amatr+1);
_mm512_store_ps(_amatr+1, a);
}
int main(int argc, char* argv[])
{
__attribute__((aligned(64))) float _amatr[256];
for(int i=0; i<256; i++)
_amatr = i+1;
f(_amatr);
cout<<"It works\\n";
return 0;
}
[/cpp]
This code is successfully built with any compilers flags.
Application normally runs only when it built with code optimisation (without additional flags, or with anyone optimistaion flags: -O1, -O2, -O3),
[bash]
icpc -mmic PhiFunc.cpp
scp a.out mic0:~
ssh mic0
./a.out
It works
[/bash]
but segnentation fault error appears when we try to run this code compiled with -O0.
[bash]
icpc -mmic -O0 PhiFunc.cpp
scp a.out mic0:~
ssh mic0
./a.out
Segmentation fault
[/bash]
And major problem is impossibility debugging our complicated code because it have to use -O0 flag.
