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| author | Jakub Jelinek <jakub@redhat.com> | 2015-11-24 11:45:52 +0100 |
|---|---|---|
| committer | Jakub Jelinek <jakub@gcc.gnu.org> | 2015-11-24 11:45:52 +0100 |
| commit | 3788cfb513d19a9b36311b1317aff2141a2c6a65 (patch) | |
| tree | 64cec4dd60c911068b6646624ee5ba614d073759 /gcc/tree-vect-generic.c | |
| parent | 3de2a40ecdfa37efa403d4b46ef116225acb0dc0 (diff) | |
| download | gcc-3788cfb513d19a9b36311b1317aff2141a2c6a65.zip gcc-3788cfb513d19a9b36311b1317aff2141a2c6a65.tar.gz gcc-3788cfb513d19a9b36311b1317aff2141a2c6a65.tar.bz2 | |
re PR target/68483 (gcc 5.2: suboptimal code compared to 4.9)
PR target/68483
* tree-vect-generic.c (lower_vec_perm): If VEC_PERM_EXPR
is valid vec_shr pattern, don't lower it even if can_vec_perm_p
returns false.
* optabs.c (shift_amt_for_vec_perm_mask): Return NULL_RTX
whenever first is nelt or above. Don't mask expected with
2 * nelt - 1.
* gcc.target/i386/pr68483-1.c: New test.
* gcc.target/i386/pr68483-2.c: New test.
From-SVN: r230797
Diffstat (limited to 'gcc/tree-vect-generic.c')
| -rw-r--r-- | gcc/tree-vect-generic.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/gcc/tree-vect-generic.c b/gcc/tree-vect-generic.c index af1af17..2c7adf7 100644 --- a/gcc/tree-vect-generic.c +++ b/gcc/tree-vect-generic.c @@ -1272,6 +1272,30 @@ lower_vec_perm (gimple_stmt_iterator *gsi) update_stmt (stmt); return; } + /* Also detect vec_shr pattern - VEC_PERM_EXPR with zero + vector as VEC1 and a right element shift MASK. */ + if (optab_handler (vec_shr_optab, TYPE_MODE (vect_type)) + != CODE_FOR_nothing + && TREE_CODE (vec1) == VECTOR_CST + && initializer_zerop (vec1) + && sel_int[0] + && sel_int[0] < elements) + { + for (i = 1; i < elements; ++i) + { + unsigned int expected = i + sel_int[0]; + /* Indices into the second vector are all equivalent. */ + if (MIN (elements, (unsigned) sel_int[i]) + != MIN (elements, expected)) + break; + } + if (i == elements) + { + gimple_assign_set_rhs3 (stmt, mask); + update_stmt (stmt); + return; + } + } } else if (can_vec_perm_p (TYPE_MODE (vect_type), true, NULL)) return; |