For the loop in testcase of pr36630: void foo (unsigned char *x, short y) { short i;
i = 2; while (i < y) { x[i - 1] = x[i]; i = i + 1; } } we used to get # of iterations (short unsigned int) y_3(D) + 65533, bounded by 32764 and now we get scev_not_known. Also Sebastian noticed (from pr36630): > I also have remarked on one of the graphite testcases scop-matmult.c > that we had a regression in the precision of the number of iterations from > last graphite merge till yesterday's merge, i.e. from 138275 to 139870 > We used to have a symbolic number of iterations, but now the result > is scev_dont_know. I have not yet tracked this down to the patch that > produced this regression. > > Sebastian -- Summary: Failure to return number of loop iterations Product: gcc Version: 4.4.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: tree-optimization AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: irar at il dot ibm dot com http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37416