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| author | Jozef Lawrynowicz <jozefl@gcc.gnu.org> | 2018-11-07 22:06:26 +0000 |
|---|---|---|
| committer | Jozef Lawrynowicz <jozefl@gcc.gnu.org> | 2018-11-07 22:06:26 +0000 |
| commit | c2ca29d5a35f8dd62f76df48e16bbac7320660c8 (patch) | |
| tree | 1ca8080d96fb6d191045c84771064ac19c0dd628 /gcc/stor-layout.c | |
| parent | e217792beda1ca48daea497c00694a3924f992c5 (diff) | |
| download | gcc-c2ca29d5a35f8dd62f76df48e16bbac7320660c8.zip gcc-c2ca29d5a35f8dd62f76df48e16bbac7320660c8.tar.gz gcc-c2ca29d5a35f8dd62f76df48e16bbac7320660c8.tar.bz2 | |
re PR c/87691 (transparent_union attribute does not work with MODE_PARTIAL_INT)
2018-11-07 Jozef Lawrynowicz <jozef.l@mittosystems.com>
PR c/87691
gcc/ChangeLog:
* stor-layout.c (compute_record_mode): Set TYPE_MODE of UNION_TYPE
to the mode of the widest field iff the widest field has mode class
MODE_INT, or MODE_PARTIAL_INT and the union would be passed by
reference.
gcc/testsuite/ChangeLog:
* gcc.target/msp430/pr87691.c: New test.
From-SVN: r265894
Diffstat (limited to 'gcc/stor-layout.c')
| -rw-r--r-- | gcc/stor-layout.c | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/gcc/stor-layout.c b/gcc/stor-layout.c index 42df257..4f32317 100644 --- a/gcc/stor-layout.c +++ b/gcc/stor-layout.c @@ -1834,7 +1834,13 @@ compute_record_mode (tree type) /* If this field is the whole struct, remember its mode so that, say, we can put a double in a class into a DF register instead of forcing it to live in the stack. */ - if (simple_cst_equal (TYPE_SIZE (type), DECL_SIZE (field))) + if (simple_cst_equal (TYPE_SIZE (type), DECL_SIZE (field)) + /* Partial int types (e.g. __int20) may have TYPE_SIZE equal to + wider types (e.g. int32), despite precision being less. Ensure + that the TYPE_MODE of the struct does not get set to the partial + int mode if there is a wider type also in the struct. */ + && known_gt (GET_MODE_PRECISION (DECL_MODE (field)), + GET_MODE_PRECISION (mode))) mode = DECL_MODE (field); /* With some targets, it is sub-optimal to access an aligned @@ -1844,10 +1850,17 @@ compute_record_mode (tree type) } /* If we only have one real field; use its mode if that mode's size - matches the type's size. This only applies to RECORD_TYPE. This - does not apply to unions. */ + matches the type's size. This generally only applies to RECORD_TYPE. + For UNION_TYPE, if the widest field is MODE_INT then use that mode. + If the widest field is MODE_PARTIAL_INT, and the union will be passed + by reference, then use that mode. */ poly_uint64 type_size; - if (TREE_CODE (type) == RECORD_TYPE + if ((TREE_CODE (type) == RECORD_TYPE + || (TREE_CODE (type) == UNION_TYPE + && (GET_MODE_CLASS (mode) == MODE_INT + || (GET_MODE_CLASS (mode) == MODE_PARTIAL_INT + && targetm.calls.pass_by_reference (pack_cumulative_args (0), + mode, type, 0))))) && mode != VOIDmode && poly_int_tree_p (TYPE_SIZE (type), &type_size) && known_eq (GET_MODE_BITSIZE (mode), type_size)) |