From ff166d81d9a36cf86e4c5a50d686a35c58292051 Mon Sep 17 00:00:00 2001 From: Marek Polacek Date: Fri, 19 Apr 2013 08:18:29 +0000 Subject: [PATCH] backport: re PR tree-optimization/48189 (ICE: SIGFPE (division by zero) in in predict_loops () at predict.c:991 with --param max-predicted-iterations=0) Backport from mainline 2013-01-08 Steven Bosscher Jakub Jelinek 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. From-SVN: r198085 --- gcc/ChangeLog | 10 ++++++++++ gcc/predict.c | 8 +++++++- gcc/testsuite/ChangeLog | 9 +++++++++ gcc/testsuite/gcc.dg/pr48189.c | 13 +++++++++++++ 4 files changed, 39 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/gcc.dg/pr48189.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 92c1e2219dce..713ececa0a83 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,13 @@ +2013-04-19 Marek Polacek + + Backport from mainline + 2013-01-08 Steven Bosscher + Jakub Jelinek + + 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. + 2013-04-16 Jack Howarth Backport from mainline diff --git a/gcc/predict.c b/gcc/predict.c index c12b45f12de9..2f550e74e18b 100644 --- a/gcc/predict.c +++ b/gcc/predict.c @@ -983,7 +983,8 @@ 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; @@ -1005,6 +1006,11 @@ 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 7fc674384d44..a719d45e8f4a 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,12 @@ +2013-04-19 Marek Polacek + + Backport from mainline + 2013-01-08 Steven Bosscher + Jakub Jelinek + + PR tree-optimization/48189 + * gcc.dg/pr48189.c: New test. + 2013-04-15 Rainer Orth * gcc.dg/torture/pr53922.c: Skip on alpha*-*-osf*. diff --git a/gcc/testsuite/gcc.dg/pr48189.c b/gcc/testsuite/gcc.dg/pr48189.c new file mode 100644 index 000000000000..86b995dc9848 --- /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]; +} -- 2.47.2