diff options
| author | Richard Sandiford <richard.sandiford@arm.com> | 2019-04-18 12:29:56 +0000 |
|---|---|---|
| committer | Richard Sandiford <rsandifo@gcc.gnu.org> | 2019-04-18 12:29:56 +0000 |
| commit | cd7f7c54a43c435152b2ac76b6e74ae6a3430472 (patch) | |
| tree | d7ec130591e850d27f196e742e40bfba9f1d7602 /gcc/combine.c | |
| parent | e62817edaecb4c8cb5a4f3c608f0ea52276449a1 (diff) | |
| download | gcc-cd7f7c54a43c435152b2ac76b6e74ae6a3430472.zip gcc-cd7f7c54a43c435152b2ac76b6e74ae6a3430472.tar.gz gcc-cd7f7c54a43c435152b2ac76b6e74ae6a3430472.tar.bz2 | |
Fix two ubsan failures (PR85164)
Two fixes for UB when handling very large offsets. The calculation in
force_int_to_mode would have been correct if signed integers used modulo
arithmetic, so just switch to unsigned types. The calculation in
rtx_addr_can_trap_p_1 didn't handle overflow properly, so switch to
known_subrange_p instead (which is supposed to handle all cases).
2019-04-18 Richard Sandiford <richard.sandiford@arm.com>
gcc/
PR middle-end/85164
* combine.c (force_int_to_mode): Cast the argument rather than
the result of known_alignment.
* rtlanal.c (rtx_addr_can_trap_p_1): Use known_subrange_p.
gcc/testsuite/
PR middle-end/85164
* gcc.dg/pr85164-1.c, gcc.dg/pr85164-2.c: New tests.
From-SVN: r270442
Diffstat (limited to 'gcc/combine.c')
| -rw-r--r-- | gcc/combine.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/gcc/combine.c b/gcc/combine.c index 5616e6b..4de759a 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -8946,7 +8946,7 @@ force_int_to_mode (rtx x, scalar_int_mode mode, scalar_int_mode xmode, /* If X is (minus C Y) where C's least set bit is larger than any bit in the mask, then we may replace with (neg Y). */ if (poly_int_rtx_p (XEXP (x, 0), &const_op0) - && (unsigned HOST_WIDE_INT) known_alignment (const_op0) > mask) + && known_alignment (poly_uint64 (const_op0)) > mask) { x = simplify_gen_unary (NEG, xmode, XEXP (x, 1), xmode); return force_to_mode (x, mode, mask, next_select); |