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| author | Richard Biener <rguenther@suse.de> | 2021-07-01 10:35:38 +0200 |
|---|---|---|
| committer | Richard Biener <rguenther@suse.de> | 2021-07-01 12:31:21 +0200 |
| commit | a3aaba68405751bae3f630669515b7ecdf77efa6 (patch) | |
| tree | 35e469a3db7ff4960a247fd0b1ad7de13ca3a765 | |
| parent | 9f6aeb85ee87c6b4e580b6b71e26cbe99e1dab70 (diff) | |
| download | gcc-a3aaba68405751bae3f630669515b7ecdf77efa6.zip gcc-a3aaba68405751bae3f630669515b7ecdf77efa6.tar.gz gcc-a3aaba68405751bae3f630669515b7ecdf77efa6.tar.bz2 | |
tree-optimization/100778 - fix placement of trapping vectorized ops
This avoids placing possibly trapping vectorized operations where
the corresponding scalar operation was possibly not executed.
2021-01-07 Richard Biener <rguenther@suse.de>
PR tree-optimization/100778
* tree-vect-slp.c (vect_schedule_slp_node): Do not place trapping
vectorized ops ahead of their scalar BB.
* gcc.dg/torture/pr100778.c: New testcase.
| -rw-r--r-- | gcc/testsuite/gcc.dg/torture/pr100778.c | 31 | ||||
| -rw-r--r-- | gcc/tree-vect-slp.c | 15 |
2 files changed, 46 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.dg/torture/pr100778.c b/gcc/testsuite/gcc.dg/torture/pr100778.c new file mode 100644 index 0000000..7997f2f --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr100778.c @@ -0,0 +1,31 @@ +/* { dg-do run { target *-*-*gnu* } } */ +/* { dg-additional-options "-fno-tree-sink -fno-math-errno -ftree-vectorize -D_GNU_SOURCE" } */ +/* { dg-require-effective-target fenv_exceptions } */ + +#include <fenv.h> + +double a[2]; +void __attribute__((noipa)) foo () +{ + double x = a[0]; + double y = a[1]; + double norm = __builtin_sqrt (x*x + y*y); + if (norm > 1.) + { + x = x / norm; + y = y / norm; + } + a[0] = x; + a[1] = y; +} + +int main() +{ + feenableexcept (FE_INVALID); + a[0] = 0.; + a[1] = 0.; + foo (); + if (a[0] != 0. || a[1] != 0.) + __builtin_abort (); + return 0; +} diff --git a/gcc/tree-vect-slp.c b/gcc/tree-vect-slp.c index 966b281..f08797c 100644 --- a/gcc/tree-vect-slp.c +++ b/gcc/tree-vect-slp.c @@ -7100,6 +7100,21 @@ vect_schedule_slp_node (vec_info *vinfo, gcc_assert (seen_vector_def); si = gsi_after_labels (as_a <bb_vec_info> (vinfo)->bbs[0]); } + else if (is_a <bb_vec_info> (vinfo) + && gimple_bb (last_stmt) != gimple_bb (stmt_info->stmt) + && gimple_could_trap_p (stmt_info->stmt)) + { + /* We've constrained possibly trapping operations to all come + from the same basic-block, if vectorized defs would allow earlier + scheduling still force vectorized stmts to the original block. + This is only necessary for BB vectorization since for loop vect + all operations are in a single BB and scalar stmt based + placement doesn't play well with epilogue vectorization. */ + gcc_assert (dominated_by_p (CDI_DOMINATORS, + gimple_bb (stmt_info->stmt), + gimple_bb (last_stmt))); + si = gsi_after_labels (gimple_bb (stmt_info->stmt)); + } else if (is_a <gphi *> (last_stmt)) si = gsi_after_labels (gimple_bb (last_stmt)); else |