Hello.
Similar to what was done in Marek's r202113, when op1 is a SAVE_EXPR it must
be evaluated before condition, in order to be able to deliver the operand
to real shifting. And not just to a BB where ubsan report function is called.
Patch can bootstrap on ppc64le-redhat-linux and survives regression tests.
Apart from that make check RUNTESTFLAGS="ubsan.exp" works on x86_64-linux-gnu.
Ready to be installed?
Martin
>From 2ff2e17d82ee85b09cb5f83afbee70f8b1a84f4f Mon Sep 17 00:00:00 2001
From: marxin <mli...@suse.cz>
Date: Fri, 7 Apr 2017 12:21:44 +0200
Subject: [PATCH] Evaluate a SAVE_EXPR before an UBSAN check (PR
sanitizer/80350).
gcc/c-family/ChangeLog:
2017-04-07 Martin Liska <mli...@suse.cz>
PR sanitizer/80350
* c-ubsan.c (ubsan_instrument_shift): Evaluate RHS before
doing an UBSAN check.
gcc/testsuite/ChangeLog:
2017-04-07 Martin Liska <mli...@suse.cz>
PR sanitizer/80350
* c-c++-common/ubsan/pr80350.c: New test.
---
gcc/c-family/c-ubsan.c | 4 +++-
gcc/testsuite/c-c++-common/ubsan/pr80350.c | 17 +++++++++++++++++
2 files changed, 20 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/c-c++-common/ubsan/pr80350.c
diff --git a/gcc/c-family/c-ubsan.c b/gcc/c-family/c-ubsan.c
index 91bdef88320..ef45abdd19e 100644
--- a/gcc/c-family/c-ubsan.c
+++ b/gcc/c-family/c-ubsan.c
@@ -171,7 +171,9 @@ ubsan_instrument_shift (location_t loc, enum tree_code code,
/* In case we have a SAVE_EXPR in a conditional context, we need to
make sure it gets evaluated before the condition. */
- t = fold_build2 (COMPOUND_EXPR, TREE_TYPE (t), unshare_expr (op0), t);
+ t = fold_build2 (COMPOUND_EXPR, TREE_TYPE (t),
+ fold_build2 (COMPOUND_EXPR, TREE_TYPE (op1),
+ unshare_expr (op0), unshare_expr (op1)), t);
enum sanitize_code recover_kind = SANITIZE_SHIFT_EXPONENT;
tree else_t = void_node;
diff --git a/gcc/testsuite/c-c++-common/ubsan/pr80350.c b/gcc/testsuite/c-c++-common/ubsan/pr80350.c
new file mode 100644
index 00000000000..317d2facaf7
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/ubsan/pr80350.c
@@ -0,0 +1,17 @@
+/* PR target/80310 */
+/* { dg-do run } */
+/* { dg-options "-O0 -fsanitize=shift -fno-sanitize-recover=shift" } */
+
+unsigned int x = 1;
+unsigned int y = 0;
+
+void foo() {
+ y = 1 >> (!x * 1111);
+}
+
+int main () {
+ foo ();
+ if (y != 1)
+ __builtin_abort ();
+ return 0;
+}
--
2.12.2
