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| author | Jonathan Wright <jonathan.wright@arm.com> | 2021-10-11 23:02:16 +0100 |
|---|---|---|
| committer | Jonathan Wright <jonathan.wright@arm.com> | 2021-11-04 14:51:09 +0000 |
| commit | 4e5929e4575922015ff4634af4dea59c59a44f10 (patch) | |
| tree | d8e3a95b4faed8b7c545c7f3f4e0869b6ef085ba | |
| parent | 2fc20260619b9f68044b7a3eb042726a382b5002 (diff) | |
| download | gcc-4e5929e4575922015ff4634af4dea59c59a44f10.zip gcc-4e5929e4575922015ff4634af4dea59c59a44f10.tar.gz gcc-4e5929e4575922015ff4634af4dea59c59a44f10.tar.bz2 | |
gcc/expmed.c: Ensure vector modes are tieable before extraction
Extracting a bitfield from a vector can be achieved by casting the
vector to a new type whose elements are the same size as the desired
bitfield, before generating a subreg. However, this is only an
optimization if the original vector can be accessed in the new
machine mode without first being copied - a condition denoted by the
TARGET_MODES_TIEABLE_P hook.
This patch adds a check to make sure that the vector modes are
tieable before attempting to generate a subreg. This is a necessary
prerequisite for a subsequent patch that will introduce new machine
modes for Arm Neon vector-tuple types.
gcc/ChangeLog:
2021-10-11 Jonathan Wright <jonathan.wright@arm.com>
* expmed.c (extract_bit_field_1): Ensure modes are tieable.
| -rw-r--r-- | gcc/expmed.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/gcc/expmed.c b/gcc/expmed.c index bbdd0e7..4abce11 100644 --- a/gcc/expmed.c +++ b/gcc/expmed.c @@ -1735,7 +1735,8 @@ extract_bit_field_1 (rtx str_rtx, poly_uint64 bitsize, poly_uint64 bitnum, FOR_EACH_MODE_FROM (new_mode, new_mode) if (known_eq (GET_MODE_SIZE (new_mode), GET_MODE_SIZE (GET_MODE (op0))) && known_eq (GET_MODE_UNIT_SIZE (new_mode), GET_MODE_SIZE (tmode)) - && targetm.vector_mode_supported_p (new_mode)) + && targetm.vector_mode_supported_p (new_mode) + && targetm.modes_tieable_p (GET_MODE (op0), new_mode)) break; if (new_mode != VOIDmode) op0 = gen_lowpart (new_mode, op0); |