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| author | Richard Biener <rguenther@suse.de> | 2021-02-04 12:08:47 +0100 |
|---|---|---|
| committer | Richard Biener <rguenther@suse.de> | 2021-02-04 13:02:09 +0100 |
| commit | 7002a33d1ba81e4577d965fb9daaee146b31faa8 (patch) | |
| tree | 75b50e60b8279147077ef320209b7bd1ac11358f /gcc/tree-vect-slp.c | |
| parent | f0e618faeb619ec02dabbef203a5575fca44a7f7 (diff) | |
| download | gcc-7002a33d1ba81e4577d965fb9daaee146b31faa8.zip gcc-7002a33d1ba81e4577d965fb9daaee146b31faa8.tar.gz gcc-7002a33d1ba81e4577d965fb9daaee146b31faa8.tar.bz2 | |
tree-optimization/98855 - fix some vectorizer cost issues
This fixes us not costing vectorized bswap for SLP as well as
avoiding biasing to the vectorized side when costing single-argument
PHIs. Instead we assume coalescing here and cost them with zero cost
for both the scalar and vectorized code.
This doesn't fix the PR on its own.
2021-02-04 Richard Biener <rguenther@suse.de>
PR tree-optimization/98855
* tree-vect-loop.c (vectorizable_phi): Do not cost
single-argument PHIs.
* tree-vect-slp.c (vect_bb_slp_scalar_cost): Likewise.
* tree-vect-stmts.c (vectorizable_bswap): Also perform
costing for SLP operation.
Diffstat (limited to 'gcc/tree-vect-slp.c')
| -rw-r--r-- | gcc/tree-vect-slp.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/gcc/tree-vect-slp.c b/gcc/tree-vect-slp.c index 10b876f..2305bbd 100644 --- a/gcc/tree-vect-slp.c +++ b/gcc/tree-vect-slp.c @@ -4297,6 +4297,13 @@ vect_bb_slp_scalar_cost (vec_info *vinfo, } else if (vect_nop_conversion_p (orig_stmt_info)) continue; + /* For single-argument PHIs assume coalescing which means zero cost + for the scalar and the vector PHIs. This avoids artificially + favoring the vector path (but may pessimize it in some cases). */ + else if (is_a <gphi *> (orig_stmt_info->stmt) + && gimple_phi_num_args + (as_a <gphi *> (orig_stmt_info->stmt)) == 1) + continue; else kind = scalar_stmt; record_stmt_cost (cost_vec, 1, kind, orig_stmt_info, |