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| author | Richard Biener <rguenther@suse.de> | 2021-04-09 09:35:51 +0200 |
|---|---|---|
| committer | Richard Biener <rguenther@suse.de> | 2021-04-23 08:46:06 +0200 |
| commit | 700e542971251b11623cce877075567815f72965 (patch) | |
| tree | 7a7da8c380e72602b855075b61bb8f604e84ed24 /gcc | |
| parent | 342de04d993beaa644d0b0087c20bef5dad5bf5f (diff) | |
| download | gcc-700e542971251b11623cce877075567815f72965.zip gcc-700e542971251b11623cce877075567815f72965.tar.gz gcc-700e542971251b11623cce877075567815f72965.tar.bz2 | |
tree-optimization/99971 - improve BB vect dependence analysis
We can use TBAA even when we have a DR, do so. For the testcase
that means fully vectorizing it instead of only vectorizing
the first store group resulting in suboptimal code.
2021-04-09 Richard Biener <rguenther@suse.de>
PR tree-optimization/99971
* tree-vect-data-refs.c (vect_slp_analyze_node_dependences):
Always use TBAA for loads.
* g++.dg/vect/slp-pr99971.cc: New testcase.
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/testsuite/g++.dg/vect/slp-pr99971.cc | 36 | ||||
| -rw-r--r-- | gcc/tree-vect-data-refs.c | 18 |
2 files changed, 47 insertions, 7 deletions
diff --git a/gcc/testsuite/g++.dg/vect/slp-pr99971.cc b/gcc/testsuite/g++.dg/vect/slp-pr99971.cc new file mode 100644 index 0000000..bec6418 --- /dev/null +++ b/gcc/testsuite/g++.dg/vect/slp-pr99971.cc @@ -0,0 +1,36 @@ +// { dg-do compile } +// { dg-require-effective-target vect_int } + +struct A +{ + unsigned int a, b, c, d; + + A& operator+= (A const& that) + { + a += that.a; + b += that.b; + c += that.c; + d += that.d; + return *this; + } + + A& operator-= (A const& that) + { + a -= that.a; + b -= that.b; + c -= that.c; + d -= that.d; + return *this; + } +}; + +void test(A& x, A const& y1, A const& y2) +{ + x += y1; + x -= y2; +} + +// We want to SLP vectorize a single connected SLP subgraph with two instances +// { dg-final { scan-tree-dump-not "removing SLP instance" "slp2" } } +// { dg-final { scan-tree-dump-times "SLPing BB part" 1 "slp2" } } +// { dg-final { scan-tree-dump-times "Vectorizing SLP" 2 "slp2" } } diff --git a/gcc/tree-vect-data-refs.c b/gcc/tree-vect-data-refs.c index 97c8577..b317df5 100644 --- a/gcc/tree-vect-data-refs.c +++ b/gcc/tree-vect-data-refs.c @@ -780,16 +780,20 @@ vect_slp_analyze_node_dependences (vec_info *vinfo, slp_tree node, stmt we have to resort to the alias oracle. */ stmt_vec_info stmt_info = vinfo->lookup_stmt (stmt); data_reference *dr_b = STMT_VINFO_DATA_REF (stmt_info); - if (!dr_b) + + /* We are hoisting a load - this means we can use + TBAA for disambiguation. */ + if (!ref_initialized_p) + ao_ref_init (&ref, DR_REF (dr_a)); + if (stmt_may_clobber_ref_p_1 (stmt, &ref, true)) { - /* We are hoisting a load - this means we can use - TBAA for disambiguation. */ - if (!ref_initialized_p) - ao_ref_init (&ref, DR_REF (dr_a)); - if (stmt_may_clobber_ref_p_1 (stmt, &ref, true)) + if (!dr_b) return false; - continue; + /* Resort to dependence checking below. */ } + else + /* No dependence. */ + continue; bool dependent = false; /* If we run into a store of this same instance (we've just |