| Message ID | 20130108200540.GO7269@tucnak.redhat.com |
|---|---|
| State | New |
| Headers | show |
On Tue, 8 Jan 2013, Jakub Jelinek wrote: > Hi! > > This is Steven's patch from the PR plus mine hunk, bootstrapped/regtested on > x86_64-linux and i686-linux, ok for trunk? Ok. Thanks, Richard. > 2013-01-08 Steven Bosscher <steven@gcc.gnu.org> > Jakub Jelinek <jakub@redhat.com> > > PR tree-optimization/48189 > * predict.c (predict_loops): If max is 0, don't call compare_tree_int. > If nitercst is 0, don't predict the exit edge. > > * gcc.dg/pr48189.c: New test. > > --- gcc/predict.c.jj 2013-01-04 13:44:35.000000000 +0100 > +++ gcc/predict.c 2013-01-08 15:58:15.552884491 +0100 > @@ -1434,7 +1434,8 @@ predict_loops (void) > if (TREE_CODE (niter) == INTEGER_CST) > { > if (host_integerp (niter, 1) > - && compare_tree_int (niter, max-1) == -1) > + && max > + && compare_tree_int (niter, max - 1) == -1) > nitercst = tree_low_cst (niter, 1) + 1; > else > nitercst = max; > @@ -1456,6 +1457,11 @@ predict_loops (void) > else > continue; > > + /* If the prediction for number of iterations is zero, do not > + predict the exit edges. */ > + if (nitercst == 0) > + continue; > + > probability = ((REG_BR_PROB_BASE + nitercst / 2) / nitercst); > predict_edge (ex, predictor, probability); > } > --- gcc/testsuite/gcc.dg/pr48189.c.jj 2013-01-08 15:59:38.319433008 +0100 > +++ gcc/testsuite/gcc.dg/pr48189.c 2013-01-08 15:52:31.000000000 +0100 > @@ -0,0 +1,13 @@ > +/* PR tree-optimization/48189 */ > +/* { dg-do compile } */ > +/* { dg-options "-O --param max-predicted-iterations=0" } */ > + > +struct S { int s[8]; }; > + > +void > +foo (int *x, struct S *y) > +{ > + int i; > + for (i = 0; y[i].s[i]; i++) > + *x++ = y[i].s[i]; > +} > > Jakub > >
--- gcc/predict.c.jj 2013-01-04 13:44:35.000000000 +0100 +++ gcc/predict.c 2013-01-08 15:58:15.552884491 +0100 @@ -1434,7 +1434,8 @@ predict_loops (void) if (TREE_CODE (niter) == INTEGER_CST) { if (host_integerp (niter, 1) - && compare_tree_int (niter, max-1) == -1) + && max + && compare_tree_int (niter, max - 1) == -1) nitercst = tree_low_cst (niter, 1) + 1; else nitercst = max; @@ -1456,6 +1457,11 @@ predict_loops (void) else continue; + /* If the prediction for number of iterations is zero, do not + predict the exit edges. */ + if (nitercst == 0) + continue; + probability = ((REG_BR_PROB_BASE + nitercst / 2) / nitercst); predict_edge (ex, predictor, probability); } --- gcc/testsuite/gcc.dg/pr48189.c.jj 2013-01-08 15:59:38.319433008 +0100 +++ gcc/testsuite/gcc.dg/pr48189.c 2013-01-08 15:52:31.000000000 +0100 @@ -0,0 +1,13 @@ +/* PR tree-optimization/48189 */ +/* { dg-do compile } */ +/* { dg-options "-O --param max-predicted-iterations=0" } */ + +struct S { int s[8]; }; + +void +foo (int *x, struct S *y) +{ + int i; + for (i = 0; y[i].s[i]; i++) + *x++ = y[i].s[i]; +}