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| author | Richard Biener <rguenther@suse.de> | 2016-05-11 14:04:32 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2016-05-11 14:04:32 +0000 |
| commit | f35ea97de898081cb04ceaa6bca97d2b719e7c47 (patch) | |
| tree | 36b22664ec960b7983947166fc32bd195c9c804c /gcc/tree-ssa-sccvn.c | |
| parent | dff70323a39a34ba26c729f50fe45d78912133e8 (diff) | |
| download | gcc-f35ea97de898081cb04ceaa6bca97d2b719e7c47.zip gcc-f35ea97de898081cb04ceaa6bca97d2b719e7c47.tar.gz gcc-f35ea97de898081cb04ceaa6bca97d2b719e7c47.tar.bz2 | |
re PR tree-optimization/71055 (FAIL: gcc.dg/torture/pr53663-1.c -Os execution test)
2016-05-11 Richard Biener <rguenther@suse.de>
PR tree-optimization/71055
* tree-ssa-sccvn.c (vn_reference_lookup_3): When native-interpreting
sth with precision not equal to access size verify we don't chop
off bits.
* gcc.dg/torture/pr71055.c: New testcase.
From-SVN: r236122
Diffstat (limited to 'gcc/tree-ssa-sccvn.c')
| -rw-r--r-- | gcc/tree-ssa-sccvn.c | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/gcc/tree-ssa-sccvn.c b/gcc/tree-ssa-sccvn.c index 6344117..1567fb9 100644 --- a/gcc/tree-ssa-sccvn.c +++ b/gcc/tree-ssa-sccvn.c @@ -1907,14 +1907,34 @@ vn_reference_lookup_3 (ao_ref *ref, tree vuse, void *vr_, buffer, sizeof (buffer)); if (len > 0) { - tree val = native_interpret_expr (vr->type, + tree type = vr->type; + /* Make sure to interpret in a type that has a range + covering the whole access size. */ + if (INTEGRAL_TYPE_P (vr->type) + && ref->size != TYPE_PRECISION (vr->type)) + type = build_nonstandard_integer_type (ref->size, + TYPE_UNSIGNED (type)); + tree val = native_interpret_expr (type, buffer + ((offset - offset2) / BITS_PER_UNIT), ref->size / BITS_PER_UNIT); + /* If we chop off bits because the types precision doesn't + match the memory access size this is ok when optimizing + reads but not when called from the DSE code during + elimination. */ + if (val + && type != vr->type) + { + if (! int_fits_type_p (val, vr->type)) + val = NULL_TREE; + else + val = fold_convert (vr->type, val); + } + if (val) return vn_reference_lookup_or_insert_for_pieces - (vuse, vr->set, vr->type, vr->operands, val); + (vuse, vr->set, vr->type, vr->operands, val); } } } |