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author | Richard Sandiford <richard.sandiford@linaro.org> | 2018-01-16 15:13:32 +0000 |
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committer | Richard Sandiford <rsandifo@gcc.gnu.org> | 2018-01-16 15:13:32 +0000 |
commit | fb2f98bb6c5e016514bc3b93f8f1550e39e7d28f (patch) | |
tree | 202d41236e118c3135fd0ed5979c117e2ca2e0dd | |
parent | e57d9a82996838e73cc5470a1f3367e9c616b947 (diff) | |
download | gcc-fb2f98bb6c5e016514bc3b93f8f1550e39e7d28f.zip gcc-fb2f98bb6c5e016514bc3b93f8f1550e39e7d28f.tar.gz gcc-fb2f98bb6c5e016514bc3b93f8f1550e39e7d28f.tar.bz2 |
Two fixes for live-out SLP inductions (PR 83857)
vect_analyze_loop_operations was calling vectorizable_live_operation
for all live-out phis, which led to a bogus ncopies calculation in
the pure SLP case. I think v_a_l_o should only be passing phis
that are vectorised using normal loop vectorisation, since
vect_slp_analyze_node_operations handles the SLP side (and knows
the correct slp_index and slp_node arguments to pass in, via
vect_analyze_stmt).
With that fixed we hit an older bug that vectorizable_live_operation
didn't handle live-out SLP inductions. Fixed by using gimple_phi_result
rather than gimple_get_lhs for phis.
2018-01-16 Richard Sandiford <richard.sandiford@linaro.org>
gcc/
PR tree-optimization/83857
* tree-vect-loop.c (vect_analyze_loop_operations): Don't call
vectorizable_live_operation for pure SLP statements.
(vectorizable_live_operation): Handle PHIs.
gcc/testsuite/
PR tree-optimization/83857
* gcc.dg/vect/pr83857.c: New test.
From-SVN: r256747
-rw-r--r-- | gcc/ChangeLog | 7 | ||||
-rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
-rw-r--r-- | gcc/testsuite/gcc.dg/vect/pr83857.c | 30 | ||||
-rw-r--r-- | gcc/tree-vect-loop.c | 11 |
4 files changed, 51 insertions, 2 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 055e924..979f5ae 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2018-01-16 Richard Sandiford <richard.sandiford@linaro.org> + + PR tree-optimization/83857 + * tree-vect-loop.c (vect_analyze_loop_operations): Don't call + vectorizable_live_operation for pure SLP statements. + (vectorizable_live_operation): Handle PHIs. + 2018-01-16 Richard Biener <rguenther@suse.de> PR tree-optimization/83867 diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index ae57828..0e24ae4 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2018-01-16 Richard Sandiford <richard.sandiford@linaro.org> + + PR tree-optimization/83857 + * gcc.dg/vect/pr83857.c: New test. + 2018-01-16 Richard Biener <rguenther@suse.de> PR tree-optimization/83867 diff --git a/gcc/testsuite/gcc.dg/vect/pr83857.c b/gcc/testsuite/gcc.dg/vect/pr83857.c new file mode 100644 index 0000000..92e648b --- /dev/null +++ b/gcc/testsuite/gcc.dg/vect/pr83857.c @@ -0,0 +1,30 @@ +/* { dg-do run } */ +/* { dg-additional-options "-ffast-math" } */ + +#define N 100 + +double __attribute__ ((noinline, noclone)) +f (double *x, double y) +{ + double a = 0; + for (int i = 0; i < N; ++i) + { + a += y; + x[i * 2] += a; + x[i * 2 + 1] += a; + } + return a - y; +} + +double x[N * 2]; + +int +main (void) +{ + if (f (x, 5) != (N - 1) * 5) + __builtin_abort (); + return 0; +} + +/* { dg-final { scan-tree-dump "Loop contains only SLP stmts" "vect" { target vect_double } } } */ +/* { dg-final { scan-tree-dump "vectorized 1 loops" "vect" { target vect_double } } } */ diff --git a/gcc/tree-vect-loop.c b/gcc/tree-vect-loop.c index 64b9ce3..79b8186 100644 --- a/gcc/tree-vect-loop.c +++ b/gcc/tree-vect-loop.c @@ -1851,7 +1851,10 @@ vect_analyze_loop_operations (loop_vec_info loop_vinfo) ok = vectorizable_reduction (phi, NULL, NULL, NULL, NULL); } - if (ok && STMT_VINFO_LIVE_P (stmt_info)) + /* SLP PHIs are tested by vect_slp_analyze_node_operations. */ + if (ok + && STMT_VINFO_LIVE_P (stmt_info) + && !PURE_SLP_STMT (stmt_info)) ok = vectorizable_live_operation (phi, NULL, NULL, -1, NULL); if (!ok) @@ -8217,7 +8220,11 @@ vectorizable_live_operation (gimple *stmt, gcc_assert (!LOOP_VINFO_FULLY_MASKED_P (loop_vinfo)); /* Get the correct slp vectorized stmt. */ - vec_lhs = gimple_get_lhs (SLP_TREE_VEC_STMTS (slp_node)[vec_entry]); + gimple *vec_stmt = SLP_TREE_VEC_STMTS (slp_node)[vec_entry]; + if (gphi *phi = dyn_cast <gphi *> (vec_stmt)) + vec_lhs = gimple_phi_result (phi); + else + vec_lhs = gimple_get_lhs (vec_stmt); /* Get entry to use. */ bitstart = bitsize_int (vec_index); |