https://gcc.gnu.org/g:c9e94ae448ba309dba74de3ee1974a3ed9248889
commit r14-9933-gc9e94ae448ba309dba74de3ee1974a3ed9248889
Author: Jakub Jelinek <ja...@redhat.com>
Date: Fri Apr 12 10:59:54 2024 +0200
Limit special asan/ubsan/bitint returns_twice handling to calls in bbs with
abnormal pred [PR114687]
The tree-cfg.cc verifier only diagnoses returns_twice calls preceded
by non-label/debug stmts if it is in a bb with abnormal predecessor.
The following testcase shows that if a user lies in the attributes
(a function which never returns can't be pure, and can't return
twice when it doesn't ever return at all), when we figure it out,
we can remove the abnormal edges to the "returns_twice" call and perhaps
whole .ABNORMAL_DISPATCHER etc.
edge_before_returns_twice_call then ICEs because it can't find such
an edge.
The following patch limits the special handling to calls in bbs where
the verifier requires that.
2024-04-12 Jakub Jelinek <ja...@redhat.com>
PR sanitizer/114687
* gimple-iterator.cc (gsi_safe_insert_before): Only use
edge_before_returns_twice_call if bb_has_abnormal_pred.
(gsi_safe_insert_seq_before): Likewise.
* gimple-lower-bitint.cc (bitint_large_huge::lower_call): Only
push to m_returns_twice_calls if bb_has_abnormal_pred.
* gcc.dg/asan/pr114687.c: New test.
Diff:
---
gcc/gimple-iterator.cc | 6 ++++--
gcc/gimple-lower-bitint.cc | 2 +-
gcc/testsuite/gcc.dg/asan/pr114687.c | 22 ++++++++++++++++++++++
3 files changed, 27 insertions(+), 3 deletions(-)
diff --git a/gcc/gimple-iterator.cc b/gcc/gimple-iterator.cc
index ac6cb4aa414..93646262eac 100644
--- a/gcc/gimple-iterator.cc
+++ b/gcc/gimple-iterator.cc
@@ -1049,7 +1049,8 @@ gsi_safe_insert_before (gimple_stmt_iterator *iter,
gimple *g)
gimple *stmt = gsi_stmt (*iter);
if (stmt
&& is_gimple_call (stmt)
- && (gimple_call_flags (stmt) & ECF_RETURNS_TWICE) != 0)
+ && (gimple_call_flags (stmt) & ECF_RETURNS_TWICE) != 0
+ && bb_has_abnormal_pred (gsi_bb (*iter)))
{
edge e = edge_before_returns_twice_call (gsi_bb (*iter));
basic_block new_bb = gsi_insert_on_edge_immediate (e, g);
@@ -1072,7 +1073,8 @@ gsi_safe_insert_seq_before (gimple_stmt_iterator *iter,
gimple_seq seq)
gimple *stmt = gsi_stmt (*iter);
if (stmt
&& is_gimple_call (stmt)
- && (gimple_call_flags (stmt) & ECF_RETURNS_TWICE) != 0)
+ && (gimple_call_flags (stmt) & ECF_RETURNS_TWICE) != 0
+ && bb_has_abnormal_pred (gsi_bb (*iter)))
{
edge e = edge_before_returns_twice_call (gsi_bb (*iter));
gimple *f = gimple_seq_first_stmt (seq);
diff --git a/gcc/gimple-lower-bitint.cc b/gcc/gimple-lower-bitint.cc
index 4c3b7f7b68e..7e8b6e3c51a 100644
--- a/gcc/gimple-lower-bitint.cc
+++ b/gcc/gimple-lower-bitint.cc
@@ -5320,7 +5320,7 @@ bitint_large_huge::lower_call (tree obj, gimple *stmt)
arg = make_ssa_name (TREE_TYPE (arg));
gimple *g = gimple_build_assign (arg, v);
gsi_insert_before (&gsi, g, GSI_SAME_STMT);
- if (returns_twice)
+ if (returns_twice && bb_has_abnormal_pred (gimple_bb (stmt)))
{
m_returns_twice_calls.safe_push (stmt);
returns_twice = false;
diff --git a/gcc/testsuite/gcc.dg/asan/pr114687.c
b/gcc/testsuite/gcc.dg/asan/pr114687.c
new file mode 100644
index 00000000000..48cc8688176
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/asan/pr114687.c
@@ -0,0 +1,22 @@
+/* PR sanitizer/114687 */
+/* { dg-do compile } */
+
+int a;
+int foo (int);
+
+__attribute__((pure, returns_twice)) int
+bar (void)
+{
+ a = 1;
+ while (a)
+ a = 2;
+ return a;
+}
+
+int
+baz (void)
+{
+ int d = bar ();
+ foo (d);
+ return 0;
+}
