topic Re: slight delay when a console application exit in Intel® oneAPI DPC++/C++ Compiler

slight delay when a console application exit

mrusso — Sun, 11 Aug 2024 21:56:03 GMT

Hi,

I made a console application which print something and then exit, after printing instead of exit immediately, like the same application compiled with other compilers it delays the exit, what would be the reason for that?

Re: slight delay when a console application exit

Alex_Y_Intel — Tue, 13 Aug 2024 18:12:23 GMT

Why is it related to Intel DPC++/C++ compiler?

Re: slight delay when a console application exit

mrusso — Tue, 13 Aug 2024 18:29:08 GMT

Hi,

The issue seems related to optimization, when turned off, works fine, when turn on, sometime got output and sometime no output but always delay in exit.

Re: slight delay when a console application exit

Alex_Y_Intel — Tue, 13 Aug 2024 18:31:25 GMT

A reproducer and exact commands used need to be provided for understanding your issue.

Re: slight delay when a console application exit

mrusso — Tue, 13 Aug 2024 18:49:44 GMT

These are the commands:

icx /QxHOST /Ot /Qansi-alias -Qipo VRA.c -o VRASPEED
icx /QxHOST /O1 /Qansi-alias VRA.c -o VRASIZE
icx /QxHOST /O2 /Qansi-alias -Qipo VRA.c -o VRASPEED1
icx /QxHOST /O3 /Qansi-alias -Qipo VRA.c -o VRAMAXSPEED
icx /QxHOST /Os /Qansi-alias VRA.c -o VRASIZE2
icx /QxHOST /Ot /Qiiansi-alias -Qipo VRA.c -o VRASPEED2
icx /QxHOST /Od /Qansi-alias -Qipo VRA.c -o VRADISABLE ; THIS IS THE ONLY ONE THAT WORKS FINE.

and also tried:

icx /QxHOST /Ot /Qansi-alias -Qipo VRA.c -o VRASPEED -fprofile-instr-generate
VRASPEED 1.txt 3 2
llvm-profdata merge -output=code.profdata default.profraw
icx /QxHOST /Ot /Qansi-alias -Qipo VRA.c -o VRASPEED -fprofile-instr-use=code.profdata

icx /QxHOST /O1 /Qansi-alias VRA.c -o VRASIZE -fprofile-instr-generate
VRASIZE 1.txt 3 2
llvm-profdata merge -output=code.profdata default.profraw
icx /QxHOST /O1 /Qansi-alias VRA.c -o VRASIZE -fprofile-instr-use=code.profdata

icx /QxHOST /O2 /Qansi-alias -Qipo VRA.c -o VRASPEED1 -fprofile-instr-generate
VRASPEED1 1.txt 3 2
llvm-profdata merge -output=code.profdata default.profraw
icx /QxHOST /O2 /Qansi-alias -Qipo VRA.c -o VRASPEED1 -fprofile-instr-use=code.profdata

icx /QxHOST /O3 /Qansi-alias -Qipo VRA.c -o VRAMAXSPEED -fprofile-instr-generate
VRAMAXSPEED 1.txt 3 2
llvm-profdata merge -output=code.profdata default.profraw
icx /QxHOST /O3 /Qansi-alias -Qipo VRA.c -o VRAMAXSPEED -fprofile-instr-use=code.profdata

icx /QxHOST /Os /Qansi-alias VRA.c -o VRASIZE2 -fprofile-instr-generate
VRASIZE2 1.txt 3 2
llvm-profdata merge -output=code.profdata default.profraw
icx /QxHOST /Os /Qansi-alias VRA.c -o VRASIZE2 -fprofile-instr-use=code.profdata

icx /QxHOST /Ot /Qiiansi-alias -Qipo VRA.c -o VRASPEED2 -fprofile-instr-generate
VRASPEED2 1.txt 3 2
llvm-profdata merge -output=code.profdata default.profraw
icx /QxHOST /Ot /Qansi-alias -Qipo VRA.c -o VRASPEED2 -fprofile-instr-use=code.profdata

icx /QxHOST /Od /Qansi-alias -Qipo VRA.c -o VRADISABLE -fprofile-instr-generate
VRADISABLE 1.txt 3 2
llvm-profdata merge -output=code.profdata default.profraw
icx /QxHOST /Od /Qansi-alias -Qipo VRA.c -o VRADISABLE -fprofile-instr-use=code.profdata

Re: slight delay when a console application exit

mrusso — Tue, 13 Aug 2024 18:55:31 GMT

Re: slight delay when a console application exit

mrusso — Tue, 13 Aug 2024 18:56:29 GMT

Re: slight delay when a console application exit

Alex_Y_Intel — Tue, 13 Aug 2024 19:09:14 GMT

What is VRA.c ?

Re: slight delay when a console application exit

mrusso — Tue, 13 Aug 2024 19:15:19 GMT

is a source c file.

Re: slight delay when a console application exit

Alex_Y_Intel — Tue, 13 Aug 2024 19:25:14 GMT

We need to have your VRA.c source file to duplicate your observation and investigate it.

Re: slight delay when a console application exit

mrusso — Tue, 13 Aug 2024 19:32:40 GMT

to run as vra.exe 1.txt 3 2

Also please note that it works only if optimizations are disabled.

On same other compilers it works even with optimizations.

Re: slight delay when a console application exit

mrusso — Wed, 14 Aug 2024 16:48:39 GMT

Ok I found the issue:

Basically before the loop that follows, I have:

v85 = v5 + 1;

v87 = 1;

for ( j = v87; j <= v83; ++j ) //V87 TRAIN FROM, V83 PREDICT TO

{

*(int *)(handle + sizeof(int) * j) = *(int *)(byte_4BC818 + sizeof(int) * j);

}

so I had to move the line v85 = v5 + 1; after the scanf that counts how many values are in the data file, v5 is the counter.