diff options
| author | Tamar Christina <tamar.christina@arm.com> | 2018-08-21 09:55:07 +0000 |
|---|---|---|
| committer | Tamar Christina <tnfchris@gcc.gnu.org> | 2018-08-21 09:55:07 +0000 |
| commit | daa9715842345da5b9c440a9fef1ed3bc916bc18 (patch) | |
| tree | 12d634187fcdcecf0de83dafe2f8355dc44386b8 /gcc/expmed.c | |
| parent | 25d4036370f11d5c32fed965c2d47e0958cbe64a (diff) | |
| download | gcc-daa9715842345da5b9c440a9fef1ed3bc916bc18.zip gcc-daa9715842345da5b9c440a9fef1ed3bc916bc18.tar.gz gcc-daa9715842345da5b9c440a9fef1ed3bc916bc18.tar.bz2 | |
Fix DSE big-endian subreg crash on AArch64.
This patch fixes an ICE that would happen when extract_low_bits
is called with modes for which you can't extract a valid subreg.
e.g. taking a 32 bytes subreg from a 48 byte mode.
The ICE happens because convert_modes which eventually calls
simplify_gen_subreg does not expect the convertion to fail.
The assert in gen_lowpart_general would then be hit. The patch
changes it to validate the subreg before trying to convert the
modes. If the subreg is not possible we return NULL_RTX and bail
out early.
gcc/ChangeLog:
2018-08-21 Tamar Christina <tamar.christina@arm.com>
* expmed.c (extract_low_bits): Reject invalid subregs early.
gcc/testsuite/ChangeLog:
2018-08-21 Tamar Christina <tamar.christina@arm.com>
* gcc.target/aarch64/large_struct_copy.c: New test.
From-SVN: r263696
Diffstat (limited to 'gcc/expmed.c')
| -rw-r--r-- | gcc/expmed.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/gcc/expmed.c b/gcc/expmed.c index be9f0ec..e281930 100644 --- a/gcc/expmed.c +++ b/gcc/expmed.c @@ -2392,6 +2392,10 @@ extract_low_bits (machine_mode mode, machine_mode src_mode, rtx src) return NULL_RTX; src = gen_lowpart (src_int_mode, src); + if (!validate_subreg (int_mode, src_int_mode, src, + subreg_lowpart_offset (int_mode, src_int_mode))) + return NULL_RTX; + src = convert_modes (int_mode, src_int_mode, src, true); src = gen_lowpart (mode, src); return src; |