diff options
| author | ams <ams@138bc75d-0d04-0410-961f-82ee72b054a4> | 2015-03-18 14:27:13 +0000 |
|---|---|---|
| committer | ams <ams@138bc75d-0d04-0410-961f-82ee72b054a4> | 2015-03-18 14:27:13 +0000 |
| commit | 648877c4fb8aec1b59cfbb70ec0800c481fe1d03 (patch) | |
| tree | 69b1cb1f705af4cd981f939fff7d9571ae8a9784 /gcc/tree-ssa-loop-niter.c | |
| parent | a525885688f4bcb220f9e49a154c0e54a619d90c (diff) | |
| download | gcc-648877c4fb8aec1b59cfbb70ec0800c481fe1d03.tar.gz | |
Fix PR64491
2015-03-18 Andrew Stubbs <ams@codesourcery.com>
PR middle-end/64491
Revert:
2014-11-20 Andrew Stubbs <ams@codesourcery.com>
* tree-ssa-loop-niter.c (maybe_lower_iteration_bound): Warn if a loop
condition would be removed due to undefined behaviour.
2015-03-18 Andrew Stubbs <ams@codesourcery.com>
PR middle-end/64491
Revert:
2014-11-20 Andrew Stubbs <ams@codesourcery.com>
* gcc.dg/undefined-loop-1.c: New file.
* gcc.dg/undefined-loop-2.c: New file.
2014-12-24 Andrew Stubbs <ams@codesourcery.com>
PR testsuite/64032
* gcc.dg/undefined-loop-2.c: Don't allow GCC to optimize away the
loop exits too early.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@221492 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/tree-ssa-loop-niter.c')
| -rw-r--r-- | gcc/tree-ssa-loop-niter.c | 45 |
1 files changed, 0 insertions, 45 deletions
diff --git a/gcc/tree-ssa-loop-niter.c b/gcc/tree-ssa-loop-niter.c index 7f6c451c0c2..fc63825904f 100644 --- a/gcc/tree-ssa-loop-niter.c +++ b/gcc/tree-ssa-loop-niter.c @@ -3329,7 +3329,6 @@ maybe_lower_iteration_bound (struct loop *loop) struct nb_iter_bound *elt; bool found_exit = false; vec<basic_block> queue = vNULL; - vec<gimple> problem_stmts = vNULL; bitmap visited; /* Collect all statements with interesting (i.e. lower than @@ -3375,7 +3374,6 @@ maybe_lower_iteration_bound (struct loop *loop) if (not_executed_last_iteration->contains (stmt)) { stmt_found = true; - problem_stmts.safe_push (stmt); break; } if (gimple_has_side_effects (stmt)) @@ -3419,53 +3417,10 @@ maybe_lower_iteration_bound (struct loop *loop) "undefined statement must be executed at the last iteration.\n"); record_niter_bound (loop, loop->nb_iterations_upper_bound - 1, false, true); - - if (warn_aggressive_loop_optimizations) - { - bool exit_warned = false; - for (elt = loop->bounds; elt; elt = elt->next) - { - if (elt->is_exit - && wi::gtu_p (elt->bound, loop->nb_iterations_upper_bound)) - { - basic_block bb = gimple_bb (elt->stmt); - edge exit_edge = EDGE_SUCC (bb, 0); - struct tree_niter_desc niter; - - if (!loop_exit_edge_p (loop, exit_edge)) - exit_edge = EDGE_SUCC (bb, 1); - - if(number_of_iterations_exit (loop, exit_edge, - &niter, false, false) - && integer_onep (niter.assumptions) - && integer_zerop (niter.may_be_zero) - && niter.niter - && TREE_CODE (niter.niter) == INTEGER_CST - && wi::ltu_p (loop->nb_iterations_upper_bound, - wi::to_widest (niter.niter))) - { - if (warning_at (gimple_location (elt->stmt), - OPT_Waggressive_loop_optimizations, - "loop exit may only be reached after undefined behavior")) - exit_warned = true; - } - } - } - - if (exit_warned && !problem_stmts.is_empty ()) - { - gimple stmt; - int index; - FOR_EACH_VEC_ELT (problem_stmts, index, stmt) - inform (gimple_location (stmt), - "possible undefined statement is here"); - } - } } BITMAP_FREE (visited); queue.release (); - problem_stmts.release (); delete not_executed_last_iteration; } |