Hello, I am running the attached testcase (inspired from vect/vect-reduc-3.c testcase) with -O3 -fwrapv on powerpc64-linux with trunk 4.4.
Here is a snippet from the testcase:
...
unsigned short ub[N] = {0,3,6,9,12,15,18,21,24,27,30,33,36,39,42,45};
unsigned short uc[N] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
unsigned short udiff;
udiff = 0;
for (i = 0; i < n; i++) {,
udiff += (ub[i] - uc[i]);,
}
...
It seems that the use of -fwrapv flag causes part of the variables to};
be converted to short and I do not understand why.
Snippet from the .gimple dump file:
i.2 = i;
D.1654 = ub[i.2];
i.2 = i;
D.1655 = uc[i.2];
D.1656 = D.1654 - D.1655;
D.1657 = (short int) D.1656;
udiff.3 = (short int) udiff;
D.1659 = D.1657 + udiff.3;
udiff = (short unsigned int) D.1659;
Thanks,
Revital
(See attached file: test-2.c)
test-2.c
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