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author | Kewen Lin <linkw@linux.ibm.com> | 2022-06-14 00:57:01 -0500 |
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committer | Kewen Lin <linkw@linux.ibm.com> | 2022-06-14 00:57:01 -0500 |
commit | f907cf4c07cf51863dadbe90894e2ae3382bada5 (patch) | |
tree | 9afc821b19f134f4909206476dc0b1edc47e46f6 | |
parent | 077438933cf94f00cc5edf974338c11ba4bf7a39 (diff) | |
download | gcc-f907cf4c07cf51863dadbe90894e2ae3382bada5.zip gcc-f907cf4c07cf51863dadbe90894e2ae3382bada5.tar.gz gcc-f907cf4c07cf51863dadbe90894e2ae3382bada5.tar.bz2 |
vect: Move suggested_unroll_factor applying [PR105940]
As PR105940 shown, when rs6000 port tries to assign
m_suggested_unroll_factor by 4 or so, there will be ICE on:
exact_div (LOOP_VINFO_VECT_FACTOR (loop_vinfo),
loop_vinfo->suggested_unroll_factor);
In function vect_analyze_loop_2, the current place of
suggested_unroll_factor applying can't guarantee it's
applied for all cases. As the case shows, vectorizer
could retry with SLP forced off, the vf is reset by
saved_vectorization_factor which isn't applied with
suggested_unroll_factor before. It means it can end
up with one vf which neglects suggested_unroll_factor.
I think it's off design, we should move the applying
of suggested_unroll_factor after start_over.
PR tree-optimization/105940
gcc/ChangeLog:
* tree-vect-loop.cc (vect_analyze_loop_2): Move the place of
applying suggested_unroll_factor after start_over.
-rw-r--r-- | gcc/tree-vect-loop.cc | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc index 246347b..e05f8e8 100644 --- a/gcc/tree-vect-loop.cc +++ b/gcc/tree-vect-loop.cc @@ -2388,15 +2388,15 @@ vect_analyze_loop_2 (loop_vec_info loop_vinfo, bool &fatal, set of rgroups. */ gcc_assert (LOOP_VINFO_MASKS (loop_vinfo).is_empty ()); + /* This is the point where we can re-start analysis with SLP forced off. */ +start_over: + /* Apply the suggested unrolling factor, this was determined by the backend during finish_cost the first time we ran the analyzis for this vector mode. */ if (loop_vinfo->suggested_unroll_factor > 1) LOOP_VINFO_VECT_FACTOR (loop_vinfo) *= loop_vinfo->suggested_unroll_factor; - /* This is the point where we can re-start analysis with SLP forced off. */ -start_over: - /* Now the vectorization factor is final. */ poly_uint64 vectorization_factor = LOOP_VINFO_VECT_FACTOR (loop_vinfo); gcc_assert (known_ne (vectorization_factor, 0U)); |