diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ipa-modref.c | 13 | ||||
| -rw-r--r-- | gcc/ipa-pure-const.c | 22 |
2 files changed, 35 insertions, 0 deletions
diff --git a/gcc/ipa-modref.c b/gcc/ipa-modref.c index 55fa873..2c89c63 100644 --- a/gcc/ipa-modref.c +++ b/gcc/ipa-modref.c @@ -1750,6 +1750,19 @@ modref_access_analysis::analyze () for (si = gsi_start_nondebug_after_labels_bb (bb); !gsi_end_p (si); gsi_next_nondebug (&si)) { + /* NULL memory accesses terminates BB. These accesses are known + to trip undefined behaviour. gimple-ssa-isolate-paths turns them + to volatile accesses and adds builtin_trap call which would + confuse us otherwise. */ + if (infer_nonnull_range_by_dereference (gsi_stmt (si), + null_pointer_node)) + { + if (dump_file) + fprintf (dump_file, " - NULL memory access; terminating BB\n"); + if (flag_non_call_exceptions) + set_side_effects (); + break; + } analyze_stmt (gsi_stmt (si), always_executed); /* Avoid doing useles work. */ diff --git a/gcc/ipa-pure-const.c b/gcc/ipa-pure-const.c index fea8b08..25503f3 100644 --- a/gcc/ipa-pure-const.c +++ b/gcc/ipa-pure-const.c @@ -1097,6 +1097,28 @@ analyze_function (struct cgraph_node *fn, bool ipa) !gsi_end_p (gsi); gsi_next (&gsi)) { + /* NULL memory accesses terminates BB. These accesses are known + to trip undefined behaviour. gimple-ssa-isolate-paths turns them + to volatile accesses and adds builtin_trap call which would + confuse us otherwise. */ + if (infer_nonnull_range_by_dereference (gsi_stmt (gsi), + null_pointer_node)) + { + if (dump_file) + fprintf (dump_file, " NULL memory access; terminating BB%s\n", + flag_non_call_exceptions ? "; looping" : ""); + if (flag_non_call_exceptions) + { + l->looping = true; + if (stmt_can_throw_external (cfun, gsi_stmt (gsi))) + { + if (dump_file) + fprintf (dump_file, " can throw externally\n"); + l->can_throw = true; + } + } + break; + } check_stmt (&gsi, l, ipa); if (l->pure_const_state == IPA_NEITHER && l->looping |