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| author | Richard Biener <rguenther@suse.de> | 2021-05-28 14:26:06 +0200 |
|---|---|---|
| committer | Richard Biener <rguenther@suse.de> | 2021-05-28 15:18:27 +0200 |
| commit | f7a07f5a5d8065e7f11133dd1f4ad3510ab2195b (patch) | |
| tree | 07149196d312e7880dfd71f84e0e87d6c66cec78 /gcc | |
| parent | f838e3ccf8d2849980e9d0f70aa60ecd2eb5772c (diff) | |
| download | gcc-f7a07f5a5d8065e7f11133dd1f4ad3510ab2195b.zip gcc-f7a07f5a5d8065e7f11133dd1f4ad3510ab2195b.tar.gz gcc-f7a07f5a5d8065e7f11133dd1f4ad3510ab2195b.tar.bz2 | |
tree-optimization/100778 - avoid cross-BB vectorization of trapping op
This avoids vectorizing a possibly trapping operation when lanes
are handled in different BBs. I spotted this when working on the
originally reported issue in PR100778.
2021-05-28 Richard Biener <rguenther@suse.de>
PR tree-optimization/100778
* tree-vect-slp.c (vect_build_slp_tree_1): Prevent possibly
trapping ops in different BBs.
* gcc.dg/vect/bb-slp-pr100778-1.c: New testcase.
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/testsuite/gcc.dg/vect/bb-slp-pr100778-1.c | 18 | ||||
| -rw-r--r-- | gcc/tree-vect-slp.c | 4 |
2 files changed, 20 insertions, 2 deletions
diff --git a/gcc/testsuite/gcc.dg/vect/bb-slp-pr100778-1.c b/gcc/testsuite/gcc.dg/vect/bb-slp-pr100778-1.c new file mode 100644 index 0000000..9f8b7ee --- /dev/null +++ b/gcc/testsuite/gcc.dg/vect/bb-slp-pr100778-1.c @@ -0,0 +1,18 @@ +/* { dg-do compile } */ +/* { dg-require-effective-target vect_double } */ + +double foo (int x, double *p) +{ + double res = p[0] + p[1]; + double tem = p[0] / x; + if (x) + { + p[0] = tem; + p[1] /= x; + } + return res + tem; +} + +/* We may not SLP vectorize the FP division because it can trap and it + is distributed between two basic-blocks. */ +/* { dg-final { scan-tree-dump "Build SLP failed: different BB for PHI or possibly trapping operation in _\[0-9\]+ = _\[0-9\]+ / _\[0-9\]+;" "slp2" } } */ diff --git a/gcc/tree-vect-slp.c b/gcc/tree-vect-slp.c index 0ec92b0..ca1539e 100644 --- a/gcc/tree-vect-slp.c +++ b/gcc/tree-vect-slp.c @@ -1214,14 +1214,14 @@ vect_build_slp_tree_1 (vec_info *vinfo, unsigned char *swap, } } - if (phi_p + if ((phi_p || gimple_could_trap_p (stmt_info->stmt)) && (gimple_bb (first_stmt_info->stmt) != gimple_bb (stmt_info->stmt))) { if (dump_enabled_p ()) dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location, "Build SLP failed: different BB for PHI " - "in %G", stmt); + "or possibly trapping operation in %G", stmt); /* Mismatch. */ continue; } |