diff options
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/predict.c | 10 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/pr48189.c | 13 |
4 files changed, 33 insertions, 2 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index b29c10b..1d37b78 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2013-01-09 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. + 2013-01-08 John David Anglin <dave.anglin@nrc-cnrc.gc.ca> * config/pa/pa.h (VAL_U6_BITS_P): Define. diff --git a/gcc/predict.c b/gcc/predict.c index 0c16b53..67a5f74 100644 --- a/gcc/predict.c +++ b/gcc/predict.c @@ -1,6 +1,6 @@ /* Branch prediction routines for the GNU compiler. Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010, - 2011, 2012 Free Software Foundation, Inc. + 2011, 2012, 2013 Free Software Foundation, Inc. This file is part of GCC. @@ -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); } diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index f222874..22e5f53 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2013-01-09 Jakub Jelinek <jakub@redhat.com> + + PR tree-optimization/48189 + * gcc.dg/pr48189.c: New test. + 2013-01-04 Jan Hubicka <jh@suse.cz> PR tree-optimization/55823 diff --git a/gcc/testsuite/gcc.dg/pr48189.c b/gcc/testsuite/gcc.dg/pr48189.c new file mode 100644 index 0000000..86b995d --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr48189.c @@ -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]; +} |